HomeMy WebLinkAbout; Multiple Habitat Conservation Program (MHCP); Habitat Management Plan - Carlsbad Subarea Plan Biological and Conference Opinions FWS-SDG-847.4; 2004-11-09United States Department of the Interior
- FISH AND WILDLIFE SERVICE
Ecological Services Carlsbad Fish and Wildlife Office
6010 Hidden Valley Road
Carlsbad, California 92009
In Reply Refer To:
FWS-SDG-847.4
Memorandum
To: Field Supervisor
Carlsbad Fish and Wildlife Office
NOV 08
n n
From: Assistant Field Supervi '
Carlsbad Fish and Wil
Subject : Subregional Multiple Habitat Conservation Plan and the City of Carlsbad Subarea
Plaaabitat Management Plan, San Diego County, California (1 -6-00-F-847.4)
This document constitutes the Fish and Wildlife Service's (Service) Biological and Conference
Opinions (Opinion) prepared pursuant to section 7 of the Endangered Species Act of 1973, as
amended (Act), on the effects of the following Service actions on listed species and critical
habitats: (1) issuance of an incidental take permit under section 10(a)( 1)(B) of the Act to the City
of Carlsbad (City) for initially 24 listed or sensitive species and conditionally for an additional
19 listed or sensitive species based on the subregional Multiple Habitat Conservation Plan
(MHCP) and the City's Subarea Plamabitat Management Plan (HMF'); and (2) signing the
associated Implementing Agreement (IA) by and among the Service, the California Department
of Fish and Game (Department), and the City for the "-related incidental take permit.
This Opinion was prepared using the following information:
1. The HMP, dated December 1999, with addendum #1 dated December 1999, and
addendum #2 dated February 2003 ;
2. The draft IA by and between the Service, Department, and the City, dated June 2004;
3. The MHCP, Volumes 1-3, dated March 2003;
4. The Final EIS/EIR for Threatened and Endangered Species Due to the Urban Growth
within the Multiple Habitat Conservation Program Planning Area, dated March 2003;
5. The Service's Special Rule concerning take of the threatened coastal California
gnatcatcher (58 FR 65088); and
6. Other information in the Service's files.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The complete administrative record for this consultation is on file at the Carlsbad Fish and
Wildlife Office.
DESCRIPTION OF THE PROPOSED ACTION
The proposed incidental take permit and IA are necessary to ensure the City’s compliance with
the Act for the incidental take of listed species in conjunction with anticipated habitat loss and
disturbance associated with urban development and limited municipal development as described
in the MHCP, and the City’s HMP and associated draft Urgency Ordinance, all of which are
hereby incorporated into this Opinion by reference.
2
The MHCP involves planning at two general levels: (1) the subregional program level; and (2)
the City subarea plan level. The subregional program level addresses a 175-square-mile area
encompassing the seven incorporated cities of northwestern San Diego County (Carlsbad,
Encinitas, Escondido, Oceanside, San Marcos, Solana Beach, and Vista). The subregional
program is described in Volume 1 of the MHCP. Volume 1 documents the processes,
guidelines, and other features that are common to all subarea plans. It contains the overall
conservation strategy for the subregion and documents the conservation actions that collectively
will guarantee the protection of species covered by individual subarea plans. It also describes
the cooperation and institutional mechanisms through which participants will coordinate MHCP
implementation.
The MHCP does not authorize the incidental taking of federally listed species or otherwise serve
as the sole basis for any permits or authorizations. The MHCP includes a biological analysis and
permitting conditions for each species proposed for coverage in Volume 2, and a framework for
biological monitoring and management in Volume 3. Effects of implementing the MHCP were
analyzed in an Environmental Impact Statement (EIS) dated March 2003.
The MHCP is comprised of all seven cities, however, each MHCP-participating city stands
independent of the other cities in that they would each receive a separate permit. Each city will
submit, with their individual incidental take permit application, a detailed subarea plan and IA
that conforms to the MHCP. The MHCP plan is intended to be phased over time through the
periodic addition of participating entities. Once all the subarea plans are implemented consistent
with the MHCP (based on adequate findings and regional funding), 61 listed or sensitive species
are expected to be adequately conserved within the planning area for the MHCP.
This Opinion addresses the effects of the MHCP and issuing an incidental take permit to the City
on listed species and critical habitat, based on the City’s commitment to implement the MHCP in
the context of their HMP. Terms used in this Opinion are consistent with those defined in
section 3.0 of the draft IA and section B of the HMP. The HMP stands independent of the other
cities draft subarea plans. Each remaining subarea plan will be analyzed in a separate biological
opinion at the time each participating city submits its permit application, final subarea plan, and
draft IA.
A more detailed description of the MHCP and HMP are presented below after a discussion of
covered species.
i
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 3
Covered Species
The proposed incidental take permit would “cover” the species listed in Tables 1 through 3
below. For purposes of this Opinion, all the species listed in Tables 1 through 3 occur or have
the potential to occur within the action area during the permit period, and may be adversely
affected by the action.
Table 1 consists of species for which the City will have “stand alone” coverage; that is, the City
will have take authorization for the animal species for which take is expected, as described in the
species evaluation section for each species, regardless of the participation or continued
participation of any other MHCP “Participating Jurisdiction”. Please note, the HMP will not
result in take of all animals species. Some species are protected from take using both the Federal
and State definitions due to the conditions of coverage for certain species in the MHCP. Most of
these species are also State fully protected species for which take under State law is not
permitable.
In contrast, the City of Carlsbad will not receive coverage for the species listed in Table 2 until
other MHCP Participating Jurisdictions obtain coverage for these species through an existing,
legally operative incidental take permit. In the event that one of the other Participating
Jurisdictions’ permits is no longer legally operative, then the coverage of the species in Table 2
accorded to the City of Carlsbad would cease. There are two species in Table 2 which also
require the City to commit additional funding to ensure management and monitoring activities
occur for this species throughout the City. Thus, even if the respective other Participating
Jurisdiction receives an operative legal incidental take permit, the City will not receive coverage
for these two species until sufficient funds are provided to manage and monitor these two
species.
While the species listed in Table 2 are addressed in Carlsbad’s HMP, they will be primarily
addressed through the other Participating Jurisdictions’ Subarea Plans once approved and will
benefit from the Carlsbad Subarea Plan. Table 2 species will benefit from the Carlsbad Subarea
Plan’s contribution to the system of complementary and interlinked preserves created under the
MHCP. For this reason, they will be included as Covered Species under the City’s Subarea Plan
once the respective other Cities receive incidental take permits for their subarea plans. Thus,
development that would adversely affect any of the species in Table 2 could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 2 requires the City to submit in writing a request for coverage,
including documentation of compliance with the necessary conditions of legally operative
permits by other Participating Jurisdictions, funding assurances, and/or legal access and control.
Coverage for these species shall not become effective until such time as both the Service and
California Department of Fish and Game concur in writing that these conditions have been
satisfied.
The species listed in Table 3 will become Covered Species once the City has adequate funding
and legal access to manage and monitor these species consistent with the requirements of the
I
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 4
MHCP (see Volume 3). There are six species in Table 3 that also require the City to ensure the
vernal pools located adjacent to the Poinsettia Train Station in Carlsbad are protected, managed,
and monitored before coverage for these species would be received. Thus, even if additional
funds are available for management and monitoring of these species, the City will not receive
coverage for these species until the City can ensure access and management of these pools. In
addition, there is one species in Table 3 that also requires other Participating Jurisdictions to
receive an operative legal incidental take permit, in addition to the City needing additional funds,
for the City to receive coverage for this species. This scenario is no different than some of the
species in Table 2. Thus, once again, development that would adversely affect any of the species
in Table 3 could not be permitted under Carlsbad’s HMP until such coverage is received by the
City. The process for initiating coverage for species in Table 2 requires the City to submit in
writing a request for coverage, including documentation of compliance with the necessary
conditions of legally operative permits by other Participating Jurisdictions, funding assurances,
and/or legal access and control. Coverage for these species shall not become effective until such
time as both the Service and California Department of Fish and Game concur in writing that
these conditions have been satisfied.
The City will not receive coverage for the species listed in Table 4. However, these species will
be analyzed in this Opinion because they are proposed for coverage under the MHCP and were
fully analyzed in MHCP (Volume 2) and the EIS. Thus, we will analyze the MHCP’s effect on
these species and whether permitting the City’s HMP will violate section 7(a)(2) of the Act. The
following species listed in Table 4 are federally listed: arroyo toad, quino checkerspot butterfly,
Stephens’ kangaroo rat, and Pacific pocket mouse. These species were evaluated for coverage
under the MHCP (see Table 4). None of these species are expected to occur within the HMP
area and the City has not committed to adopting the measures necessary to receive such
coverage. Therefore, these species are not likely to be adversely affected by the issuance of an
incidental take permit to the City. The other 14 species on Table 4 are not federally listed. All
of these species either occur or have the potential to occur in the City. Even though the City is
not requesting coverage for these species, the MHCP provides for any of the other participating
cities to potentially receive coverage for each of these species if additional measures as
described in Volume 2 of the MHCP were adopted. On that basis, the effects of the MHCP on
these species will be analyzed herein.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 5
Scientific Name - Common Name Status’ MHCP
Subregional
Plan VOl. II
Page Ref
Chorizanthe orcuttiana
Dudleya blochmaniae ssp.
blochmaniae
Euphorbia misera
Hazardia orcuttii
Quercus durnusa
Orcutt’s spineflower FE/CEME 4-56
Blochman’s dudleya FSC 4-74
Cliff spurge None 4-101
Orcutt’s hazardia FSC/NE/CT 4-111 I Nuttall’s scrub oak
Panoquina errans
Euphyes vestris hurbisoni
I FSC
Salt marsh skipper FSC/OW 4-202
Harbison’s dun skipper FSC/NE 4-196
I 4-159
White-faced ibis
Cooper’s hawk
Osprey
American peregrine falcon
FSC/SSC/OW 4-256
ssc 4-264
ssc/ow 4-269
CE/FP 4-280
Pelecanus occidentalis californicus
Plegadis chihi
Accipiter cooperii
Pandion haliaetus
Light-footed clapper rail
Western snowy plover
Elegant tern
California least tern
Southwestern willow flycatcher
Rallus longirostris levipes
Charadrius alexandrinus nivosus
Sterna elegans
Sterna antillarum browni
FE/CE/FP/OW 4-285
FT/ssc/ow 4-29 1
FSC/SSC/OW 4-299
FE/CE/FP 4-304
FE/CE/OW 4-3 14 [Empidona traillii extimus
California rufous-crowned sparrow
1 Belding’s savannah sparrow
Large-billed savannah sparrow
vireo bellii pusillus
FSC/SSC 4-366
FSC/CE/OW 4-37 I
FSC/SSC/OW 4-377
I Polioptila californica californica I Icteria virens
Aimophila rujiceps canescens
Passerculus sandwichensis beldingi
Passerculus sanwichensis rostratus
California brown pelican I FEICEIFPIOW I 4-251 I
Least Bell’s vireo
~- I FE/CE/OW I 4-321
Coastal California gnatcatcher I FT/ssc I 4-333
Yellow-breasted chat I ssc/ow I 4-360
I I
*- Reptiles
Cnemidophorus hyperythrus beldingi I Orange-throated whiptail I ssc I 4-245 I
‘ See the “Key to Legal and Management Status” that follows List 4.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 6
Scientific Name
Table 2: Species Coverage Contingent on Other MHCP Subarea Plans Being Permitted
Common Name
Acanthomintha ilicifolia
Ambrosia pumila
Ceanothus verrucosus
Dudleya viscida
Ferocactus viridescens
Quercus engelmannii
Status’q-l
Plan Vol I1 PageRef
San Diego thornmint2 FTKEME 4-9
San Diego ambrosia =/NE 4-16
Wart-stemmed ceanothus’ FSC 4-50
Sticky dudleya FSC 4-89
San Diego barrel cactus FSC 4-106
Engelmann oak None 4- 165
Scientific Name Common Name Status1 MHCPSubregional
Plan Vol I1 Page Ref
Arctostaphylos glandulosa ssp.
crassifolia
I I 4-68
FSCME
Baccharis vanessae
I FE/CE/NE/OW I 4-94
~ ~~ ~
Brodiaea filifolia
FSC
FSC/NE/OW
FTME/ow
FE/CE/NE/OW
FSC
Comarostaphylis diversifolia ssp.
diverifolia
4-1 16
4- 133
4- 140
4- 147
4- 154
Corethrogynefilaginifolia var.
1 inifol ia
~
Branchinecta sandiegonensis
Eryngium aristulatum var. parishii
San Diego fairy shrimp3 FE/wow 4- 184
Iva hayesiana
Myosurus minimus ssp. apus
Navarretia fossalis
Orcuttia californica
Pinus torreyana ssp. torreyana
Del Mar manzanita
Encinitas baccharis
- ~~
Thread-leaved brodiaea
Summer holly
Del Mar sand aster
San Diego button-celery3
San Diego marsh elder4
Little mousetai13
Spreading navarretia3
California Orcutt grass3
I Torreypine
FT/CE/NE
FT/CE/NE
FSC I 4-63
I _. I I
Invertebrates L.
I I I I Steptocephalus woottoni I Riverside fairy shrimp3 I FE/NE/OW 14-178 I
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Scientific Name
7
Common Name Status MHCP
Subregional Plan
Vol. I1 Page Ref.
Table 4:MHCP Covered Species Not Covered Under the Carlsbad Subarea Plan
Dudleya blochmaniae ssp. brevifolia
Lotus nuttallianus
Tetracoccus dioicus
Short-leaved dudleya CE/NE 4-80
Nuttall’s lotus FSC/NE 4- 122
Parry’s Tetracoccus FSC 4- 170
Scaphiopus (Spea) hammondii
Bufo californicus
Clemmys mannorata pallida
I Euphydryas editha quino 1 Quino checkerspot butterfly I 4-211 I
Western spadefoot toad ssc 4-2 15
Arroyo toad wssc 4-222
Southwestern pond turtle FSUSSC 4-233
Sialia mexicana
Amphispiza belli belli
Phrynosoma coronatum blainvellei I San Diego homed lizard I FSC/SSC 14-238 I
Western bluebird None 4-355
Bell’s sage sparrow FSC/SSC 4-380
I Aquila chrysaetos I Golden eagle I BEPNSSC 14-274 I
Lepus californicus bennetti
Felis concolor
Odocoileus hemionus fuliginata
I Campylorhynchus brunneicapillus I Coastal cactus wren I FSC/SSC/NE 14-328 I
San Diego black-tailed jackrabbit FSC/SSC 4-42 1
Mountain lion SPM 4-425
Southern mule deer RGS 4-43 1
I Dipodomys stephensi I Stephens’ kangaroo rat I 4-401 I
~~ ~~
bognathus longimembris pacificus I Pacific pocket mouse I FE/SSC/NE ~ I 4-407
I Chaetodipus fallax fallax I Northwestern San Diego pocket mouse I FSC/SSC I 4-416 I
FE
Fr
BEPA
FSC
CE
CT
FP
RGS ow
NE
Federally Endangered
Federally Threatened
Bald Eagle Protection Act
Federal Species of Concern (former Category 2 Candidate)
State Endangered
State Threatened SPM State Special Protected Mammal
State Fully Protected species SSC State Species of Special Concern
State Regulated Game Species No Federal, State, or City Status
Obligate Wetland Species in the MHCP
Narrow Endemic Species in the MHCP (Narrow Endemic standards apply to all proposed hardline, standards areas, etc. as described
in section 3.7 of MHCP Volume 1 (March 2003)
None
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Brodiaea orcuttii
Dudleya variegata
Muilla clevelandii
Animals
Cicindela hirticollis gravida
Species Not-Covered under the MHCP Subregional Plan
The following species were expected to be analyzed for coverage under the MHCP Subregional Plan,
however, due to insufficient information or the inability to provide sufficient conservation with the
MHCP planning boundary, coverage could not be provided:
-
Orcutt’s brodiaea
Variegated dudleya
San Diego goldenstar
Sandy Beach tiger beetle
8
Cicindela latesignata obliviosa
Coelus globosus
Lycaena hermes
Oblivious tiger beetle
Globose dune beetle
Hermes copper butterfly
I Plants I
~
Circus cyaneus
Numenius americanus
1
Northern harrier
Long-billed curlew
I Aphanisma blitoides I Aphanisma I
Speotyto cunicularia hypugaea
Ammodramus savannarum
Burrowing owl
Grasshopper sparrow -~
Agelaius tricolor Tricolored blackbird
Corynorhinus townsendii pallescens
Eumops perotis cal$ornicus
Townsend’s Western big-eared bat
California mastiff bat
I Rana aurora draytoni I California red-legged frog I’
Action Area
For purposes of consultation under Section 7 of the Act, the “action area” is defined at 50 CFR 402 to
mean “all areas to be affected directly or indirectly by the Federal action and not merely the immediate
area involved in the action.” Due to the dual programmatic- and project-level aspects of the permit
application, two action areas are defined:
1. MHCP: The action area encompasses the MHCP “planning area” as defined in Volume 1 of the
MHCP; the planning area includes the following: (1) the Cities of Carlsbad, Encinitas,
Escondido, Oceanside, San Marcos, Vista, and Solana Beach; and (2) the unincorporated
gnatcatcher core area as depicted in Figure 3-3 of the MHCP (Volume 1) and including the
Choumas-Pappas property. All other County lands are excluded. All seven cities make up the
MHCP, however, they stand independent in terms of permit issuance.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 9
2. HMP: The action area is defined as all areas incorporated within the City’s jurisdiction and the
unincorporated gnatcatcher core area as depicted in Figure 3-3 of the MHCP (Volume 1) and
including the Choumas-Pappas property. All other County lands are excluded. The issuance of
a permit to the City is independent of the other cities draft subarea plans.
MHCP
I The MHCP Plan is a comprehensive, long-term habitat conservation plan that addresses the needs of
multiple species and the preservation of natural vegetation communities in north San Diego County.
The MHCP is a plan to minimize and mitigate for the potential loss of Covered Species and their
habitat due to the direct, indirect and cumulative impacts of future development of both public and
private lands within the MHCP area. The MHCP planning effort was initiated in 1991 with the
formation of a consortium of local, regional, and special purpose agencies to exchange information on
land planning issues and to coordinate preparation of local conservation plans.
The Final MHCP Plan (March 2003) was prepared for the Subregion, an area encompassing 7
jurisdictions (Carlsbad, Encinitas, Escondido, Oceanside, San Marcos, Solana Beach, and Vista) and
1 11,908 acres. The “Final Environmental Impact StatementEnvironmental Impact Report for
Theatened and Endangered Species Due to the Urban Growth within the Multiple Habitat
Conservation Program Planning Area,” dated March 2003, analyzed alternative MHCP subregional
preserve designs and selected the Focused Planning Area Number 2 alternative as the preferred
alternative. This EISEIR fully analyzed subarea plans for the following Cities: Carlsbad, Encinitas,
Escondido, Oceanside, and San Marcos.
The MHCP will be implemented through the local Subarea Plans. Each Subarea Plan prepared
pursuant to the MHCP Subregional Plan, is intended to serve as an independent multiple species
“habitat conservation plan” (HCP) pursuant to section lO(a)(2)(A) of the Act. An HCP is required for
issuance of a permit for incidental take of listed species pursuant to section lO(a)(l)(B) of the Act.
This HCP is also intended to serve as a Natural Community Conservation Plan (NCCP) pursuant to the
State of California’s NCCP Act of 1991. The following Cities have prepared subarea plans that have
been reviewed by the Service and Department (Wildlife Agencies) and public at least once: Carlsbad,
Encinitas, Escondido, Oceanside, and San Marcos. The Service has been working closely with each of
these cities to ensure their subarea plan is adequate once they request a section lO(a)( l)(B) permit
application. In fact, the cities of Oceanside and Escondido are very close to requesting such a permit.
The Wildlife Agencies have also been working with the City of Vista in preparing a draft subarea plan.
In addition, the Wildlife Agencies hold periodic MHCP meetings to ensure all the MHCP cities are
making adequate progress on their subarea plans and to ensure they will request a lO(a)( l)(B) permit
application in the near future. The Service believes that all of the MHCP cities will request such a
permit.
The MHCP preserve areas were identified through the production of a biological core and linkage area
(BCLA) map based on vegetation communities, species locations, elevation, slope, soils, drainages,
preserve design criteria, development constraints, and other physical parameters. The BCLA defined
those portions of the study area that would best contribute to a viable preserve system, and hence the
“envelope” within which the ultimate preserve system should be assembled. It also helped illustrate
where larger biological core areas could be linked to form an interconnected preserve system. Using
this information, Carlsbad and other participating cities prepared focused planning areas (FPA), which
show expected levels of conservation that could be achieved to conserve biologically valuable areas
(primarily, but not exclusively, within the BCLA). Creation of the F’PA considered not only the
biological value of lands, but also economic, legal, and other constraints to preserving these lands.
The Subregional MHCP Plan is the Focused Planning Area Number 2 alternative selected within the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 10
EISEIR. This alternative protects, manages, and monitors in perpetuity the FPA as shown in Figure
3-1 of the MHCP and covers47 percent of coastal sage scrub, 70 percent of chaparral, 53 pesent of
coastal sagekhapmal mix, and 100 percent of riparian and estuarine habitats in the study area. The
Plan also includes the conservation of 400 to 500 acres of contiguous coastal sage scrub within the
incorporated’County of San Diego centered around the cities of Carlsbad, Encinitas, and the extreme
southwest portion of San Marcos, which supports 16 to 23 pairs of the federally threatened gnatcatcher
(gnatcatcher core area). Since the additional acreage in the gnatcatcher core area is a range between
400 and 500, we are assuming worst case scenario (400 acres) for our analysis within this biological
opinion. In addition, the plan includes 338 acres of coastal sage scrub restoration in key locations
within the preserve area. Overall, 20,428 acres (68 percent) of the natural habitats found in the total
MHCP planning area would be conserved.
The preserve will be assembled by a combination of conservation of lands already in public
ownership; public acquisition of private lands with regional habitat value from willing sellers; and
private actions to conserve habitat, in conformance with development regulations and mitigation of
impacts .
Lands already in public ownership which are proposed to be included in the MHCP preserve total
10,143 acres. The federal (Bureau of Land Management) and state governments contribute 1,944
acres of habitat lands that they currently administer in the study area, the seven MHCP cities
contribute 7,142 acres of habitat lands to the preserve that they currently own, and other local agencies
own the remaining acreage in the study area.
Public acquisition of private lands is expected to occur in areas identified as priority 1 within the
MHCP Volume 1 by State or Federal government agencies if there are willing sellers and the Cities
agree to establish an endowment for habitat management and monitoring of these lands as they are
acquired. Approximately 609 acres are identified as priority 1 areas.
Private lands to conserve habitat are represented by both “hardline” preserves (lands that will be
conserved and managed for biological resources) and “softline” planning areas (areas to be delineated
based on further data and planning). Each City will need to apply development regulations and
mitigation guidelines to both public and private projects as described in Volume 1 of the MHCP and
summarized below. Individual cities may adopt different policies and guidelines or may choose not to
use mitigation ratios as a method of preserve assembly, if they demonstrate that the alternative policies
and guidelines would achieve equivalent or greater levels of conservation.
A. Avoidance of ImDacts and Allowed Encroachment: Subarea plans and their implementing
regulations and ordinances will emphasize avoidance of impacts to biologically sensitive
resources (including narrow endemic species and vernal pools) and will identify areas and
circumstances where take of Covered Species and their habitats is authorized. Projects
proposing to directly or indirectly impact Covered Species or their habitats inside the FPA
(unless a narrow endemic or species specific conditions state that all locations are protected)
must factually substantiate, in a CEQA document or in findings prepared under a local MHCP
implementing ordinance, that such impacts could not be avoided while allowing for some
economic or productive use of the property.
Feasible alternatives to avoid the impacts shall be described and analyzed, and reasons that
these alternatives were not pursued shall be fully described and supported by adequate facts. If
impacts cannot be avoided, all feasible means of minimizing encroachment into sensitive
habitats shall be fully addressed.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 11
Habitat Group
Group A. WetlandRiparian
Group B. Rare upland
Group C. Coastal sage scrub
Group D. Chaparral
Group E. Annual grasslands
Road or utility projects that are to be permitted under an MHCP subarea plan will be required
to demonstrate that crossings of sensitive habitat will occur at the least overall biologically
sensitive location and that all feasible minimization measures have been employed. Private
projects that propose to impact a sensitive resource must factually substantiate that the impact
is esiential to maintaining some economic or productive use of the property and that no
feasible alternative would eliminate or minimize the impact.
Location of Impacted Habitat
Inside Focused Outside Focused
Planning Area Planning Area
No-net-loss (see table 8)
3: 1 2: 1
2: 1 1:l
1:1 0.5:l
0.5: 1 0.5: 1
If impacts to biologically sensitive lands cannot be avoided while retaining economic or
productive use of the property, then acquisition of the property for conservation purposes shall
be pursued as a high priority, but only from willing sellers. Mitigation for unavoidable impacts
shall occur pursuant to specific mitigation criteria defined in the subarea plan, but shall be at
ratios no less than those provided in Table 6 below (see also Volume 1 of the MHCP, Tables
4-6 and 4-7):
Group F. Other lands None I None
B. Maior Populations: Certain locations within the MHCP are designated as supporting Major
Populations of particular species. Major Populations were defined by the MHCP Biological
Goals Standards and Guidelines (Ogden 1997) as those “sufficiently large to be self-sustaining
with a minimum of active or intensive management intervention (especially for plants) that
at least support enough breeding individuals to contribute reliably to the overall
metapopulation stability of the species (especially for animals).” Pursuant to this definition,
some species location points, or clusters of location points, are coded as Major Populations in
the MHCP database and mapped on the species distribution maps in the MHCP (Volume 2).
Although MHCP policies have not comprehensively established higher conservation standards
for Major Population areas relative to other occupied habitat areas (except for Narrow
Endemics - see below), subarea plans are expected to substantially conserve all Major
Populations areas identified in Volume 2 or that are found to meet the definition of Major
Population in the future.
The avoidance of impacts and allowed encroachment process must be followed for any project
in or adjacent to a Major Population site to document adequate avoidance, minimization, and
mitigation actions. In addition, the species-specific permit conditions listed in Volume 2 of the
MHCP may reference specific avoidance, minimization, and mitigation standards for selected
Major Population areas. The term “substantially conserve” is not defined within the MHCP
documents for “Major Populations”. Thus, we are assuming this term would result in at least
80 percent of a major population being conserved for purposes of this biological opinion.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 12
C.
D.
Critical Locations: Some Major Population areas, along with other areas that are considered
essential to reserve design, are designated as Critical Locations, which are defined as “areas
that must be substantially conserved for that species [or vegetation community] to be
considered adequately conserved by the MHCP.”
Examples of Critical Locations include population sites expected to contribute significant
genetic diversity for a species; areas that provide essential nesting, roosting, or wintering sites
or structures (especially for birds); essential wildlife movement corridors (especially for large
mammals and selected amphibians, reptiles, and birds), or currently unoccupied habitat needed
to accommodate population expansion (especially for narrow endemic species whose
populations must be increased to ensure extinction is precluded).
The MHCP Critical Location Policy (Appendix D of the MHCP, Volume 2) applies to all
locations listed and mapped as critical in MHCP Volume 2, or that are found to meet the
definition of critical in the future. The policy dictates that subarea plans will require maximum
avoidance and minimization of impacts; and species-specific mitigation measures for
unavoidable impacts, regardless of whether the critical location is inside or outside of the PA.
Maximum avoidance and minimization shall be interpreted as avoidance of impacts to the
degree practicable while maintaining some economic or productive use of the property, as
supported by adequate facts.
Mitigation for unavoidable impacts and management practices must be designed to achieve no-
net-loss in viability of critical populations, including no-net-loss in ecological functions for
habitat areas, wildlife movement corridors, and linkages. In no case shall a city permit more
than 20 percent gross cumulative loss of critical populations or occupied habitat acreage
(whichever is most appropriate for the species).
Narrow Endemics: Narrow endemic species are highly restricted by geographical or ecological
factors and may have important populations within the MHCP planning area, such that
substantial loss of these populations or their habitat within the MHCP planning area may
preclude the continued existence and recovery of that species. A list of the narrow endemic
species as provided in Table 3-2 of the MHCP (Volume 1) is provided below. The narrow
endemic standard is described in Appendix D of the MHCP Volume 2, section 3.7 of MHCP
Volume 1, and below.
’
Both inside and outside of the PA, impacts to narrow endemic populations shall be avoided to
the maximum extent practicable while maintaining some economic or productive use of the
property, as supported by adequate facts. Inside of FPAs, mitigation for unavoidable impacts
and management practices must be designed to achieve no-net-loss of narrow endemic
populations, occupied acreage, or population viability within the FPA. In no case, shall a city
permit more than 5 percent loss of narrow endemic populations or occupied acreage within the
FPA (whichever measure is biologically most appropriate for the species based on the best
available science).
Outside of FPAs, subarea plans must require maximum avoidance of impacts to critical and
major populations, and, in priority order, avoidance, minimization, and mitigation for impacts
to any populations. In no case shall a city permit more than 20 percent loss of narrow endemic
locations, population numbers, or occupied acreage within that city (whichever measure is
biologically most appropriate for the species).
Unavoidable impacts should be mitigated based on species-specific criteria defined in subarea
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 13
plans. Such mitigation should be designed to minimize adverse effects to species viability and
to contribute to subarea plan biological objectives. Any land conserved for mitigation that
supports narrow endemic species must be added to the MHCP preserve system and managed
for the continued viability of the population. Mitigation for unavoidable impacts must be
designed to achieve no-net-loss of narrow endemic population locations, occupied acreage, or
population viability in the MHCP subregion and preferably, but not necessarily, within each
subarea. If mitigation is proposed to occur outside the subarea plan boundary, such that a net
loss would result within the subarea, then the selected mitigation alternative must be
demonstrated with adequate facts to produce greater benefit to the species than would feasible
mitigation alternatives inside the subarea.
Regardless of location, narrow endemic populations listed as “Critical” in Table 3-7 must be
totally avoided, and any populations that are later discovered and determined to meet the
criteria for a critical population must be maximally avoided while allowing some economic or
productive use of property as supported by substantial factual evidence. If impacts to narrow
endemics cannot be avoided while retaining economic or productive use of the property, then
acquisition of the property for conservation purposes shall be pursued as a high priority, but
only from willing sellers. However, in no case shall a city permit more than 5 percent gross
cumulative loss of critical populations or occupied acreage (whichever is most appropriate for
the species).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
-
Scientific Name
Plants
14
Common Name
~~ ~
Acanthamintha ilicifolia
Ambrosia pumila
Arctostaphylos glandulosa ssp. crassifolia
___ ~~~ -
San Diego thorn-mint
San Diego ambrosia
Del Mar manzanita -~ ~~ ~
Baccharis vanessae
Brodiaea flifolia
Chorizanthe orcuttiana
~ ~~~
Encinitas baccharis
Thread-leaved brodiaea
Orcutt’s spineflower
Corethrogyne flaginifolia var. linifolia
Dudleya blochmaniae ssp. blockmaniae
Dudleya variegata
Eryngium aristulatum var. parishii
Hazardia orcuttii
Lotus nuttallianus
Orcuttia californica California Orcutt grass
I
Del Mar Mesa sand aster
Short-leaved dudleya
Variegated dudleya (not covered in MHCP)
San Diego button-celery
Orcutt’s hazardia
Nuttall’s lotus
I Animals
Muilla clevelandii
Myosurus minimus ssp. apus
Nava rretia fossalis
I
San Diego goldenstar (not covered in MHCP)
Little mousetail
Spreading navarretia
Streptocephalus woottoni
Branchinecta sandiegonensis
Cicindela latesignata obliviosa
Lycaena hermes
Euphyes vestris harbisoni
Perognathus longirnembris pacifcus
Riverside fairy shrimp
San Diego fairy shrimp
Oblivious tiger beetle (not covered in MHCP)
Harbison’s dun skipper butterfly
Coastal cactus wren
Pacific pocket mouse
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 15
Wetland Vegetation Community
Coastal salt marsh
Alkali marsh
E. Wetlands: The MHCP Plan incorporates a no-net-loss policy and provides wetland and upland
avoidance and mitigation criteria (section 3.0 of MHCP Volume 1).
Mitigation Ratio
4: 1
4: 1
~
Estuarine
Saltpadmudflats
~
4: 1
4: 1 -~~ ~ ~
Oak riparian forest
Riparian forest
Riparian woodland
Riparian scrub
Fresh water
3: 1
3: 1
3: 1
1:l to 2:l
1:l
Freshwater marsh
Flood channel
A.
B.
C.
D.
E.
1:l to 2:l
1:l t02:l
Each jurisdiction will implement the mitigation standards specified in its subarea plan
and implementing agreement. Mitigation measures in subarea plans may include
avoidance of impacts; preservation, restoration, or enhancement of habitat; or some
combination of the above consistent with achieving the goals of the subarea plan.
Disturbed wetlands 1:l to 2:l
Vernal pool 2:l to 4:1
>
Because habitat within the BCLA or FPA generally has greater conservation value than
habitat occurring in fragmented or isolated patches, subarea plans can incorporate
incentives (e.g., reduced mitigation requirements) to encourage conservation within the
BCLA or PA.
Subarea plans require site-specific analysis of biological resources, for projects where
agreements do not already exist, to detennine appropriate mitigation measures and
siting of the project.
Subarea plans may provide flexibility in both the location and type of habitat conserved,
if consistent with achieving the subarea plan’s conservation goals. This flexibility
allows subarea plans to de-emphasize or eliminate, if appropriate, historic “in-kind”
mitigation requirements and provides an opportunity to use an “ecosystem-based”
mi tigation approach.
Mitigation may be required for impacts to uncovered species, to the extent required
through CEQA and applicable federal and state regulations or local regulations.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 16
G.
F. Excluding land avoided during the land use process, land acquired for mitigation in
excess of the jurisdiction’s mitigation requirements may be used for mitigation credits
or to establish a conservation bank.
G. ’ Subarea plans also may use “in lieu” fees to accomplish all or some of the conservation
goals of the plan.
H. Subarea plans will specify the mechanism for permanent protection of lands used for
mitigation. These mechanisms include conservation easements; fee title transfer to a
public agency, conservancy, or land trust; or other mechanisms mutually agreed to by
the jurisdiction and the Wildlife Agencies.
I. Subarea plans will provide for consistency in mitigation for public and private projects.
J. Subarea plans will use definitions for grassland vegetation, disturbed land, and
agricultural lands that are provided in Appendix F of Volume 11 when project impacts
and mitigation requirements are determined.
Biological Preserve Desim and Checklist: To be consistent with the MHCP, a subarea plan’s
conservation strategy must include or address the following checklist:
A. General Preserve Design
A. High biodiversity lands as indicated by spatially representative examples
of extensive patches of sensitive vegetation communities ranked as very
high and high biological value by the MHCP Composite Habitat Value map
(Figure 2-3 of the MHCP) or as identified through subsequent fieldwork.
B. Large blocks of unfragmented habitat, following natural topography (ridges and
watersheds).
C. Large, interconnected blocks of habitat that contribute to the preservation of
wide-ranging species.
D. Key existing linkage areas between core habitat blocks; restoration or
enhancement as necessary to forge connections to other open space lands and to
other subareas or habitat patches outside the subarea plan area.
E. Configuration that minimizes edge effects between habitat preserves and
development and edge-to-preserve-area ratio.
B. Habitat Criteria
A. Total acreages and vegetation communities equivalent or better in conservation
value to those conservation targets listed in the MHCP plan (pending complete
analyses for subarea plans).
B. Representation of sensitive vegetation communities and their geographic
subassociations containing priority species in large, functioning ecosystems.
C. High quality vernal pools (primarily but not exclusively supporting sensitive
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 17
species); no-net-loss of wetland vegetation communities.
High habitat quality and microhabitats (e.g., soil type, host plant, drainages,
rock outcrops) important to sustaining long-term viable populations of
individual Covered Species.
-
D.
C. Species Criteria
A. For Covered Species, all species-specific permit conditions included at the
beginning of each species evaluation in Volume 2 of the MHCP.
B. Key regional populations of proposed Covered Species within the subarea,
including locations identified as major or critical in Volume 2 of the MHCP.
Coverage for the entire MHCP study area depends on retention and maintenance
of adequate populations of these species and their habitats within the subarea
and protection of all critical locations.
D. Management and Biological Monitoring Criteria (see also Sections 6.3 and 6.4 of the
MHCP)
A. Appropriate management within the preserve to minimize edge effects from
adjacent land uses.
B. Appropriate uses within the preserve that are compatible with and complement
the biological function of the area.
C. Biological monitoring of habitats and species that reflects priorities as
determined in categories listed above.
H. Management and Monitoring: Volume 3 of the MHCP provides guidance for the
implementation, staffing, and funding of a management and monitoring program within
MHCP. The tasks outlined in this plan are the minimum necessary. In addition to this
monitoring and management plan, each participating city has prepared a framework
management plan as part of its subarea plan that references this MHCP monitoring and
management plan and identifies the resources most important for monitoring and management
in specific parts of its subarea as determined by the goals of the MHCP. As individual areas
are dedicated to the preserve, each city must prepare an area-specific monitoring and
management plan for the newly conserved areas within its subarea. There is no minimum
acreage for which area-specific monitoring and management directives must be prepared; all
areas of the preserve must have area-specific directives. Area-specific monitoring and
management plans will include the results of baseline biological surveys, describe site-specific
threats to resources, and identify site-specific management actions to address these threats.
Area-specific monitoring and management plans must be approved by the wildlife agencies.
Area-specific monitoring and management plans must be developed for preserve lands no later
than 2 years after lands are dedicated to the preserve and implemented immediately upon
approval of the management plan.
The MHCP requires coordinated actions among the local jurisdictions, the Wildlife Agencies, and the
private sector. Generally, local jurisdictions will implement the MHCP through their normal land use
planning and approval process and through management of contributed local public lands, as specified
in the city subarea plans. Specific implementation measures contained in city subarea plans and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 18
implementing agreements may vary somewhat from the subregional guidelines described in section 5.0
of the MHCP Volume 1, as bng as they meet all the legal requirements contained in this section, as
well as all applicable MHCP biological goals and standards. A formal Elected Officials committee
will be created once two or more cities receive an incidental take permit for their respective subarea
plans. The Elected Officials committee will have, at a minimum, the following responsibilities:
A.
B.
C.
D.
E.
F.
G.
Develop the financial support required by the cities for subarea plan implementation. This is
the single most important responsibility of the Committee and should be the focus of its
activities. A guaranteed source of funds is required for the major aspects of subarea plan
implementation, including land acquisition, habitat monitoring and management, and preserve
system maintenance and operation.
Guarantee the financing and implementation coordination legally necessary to obtain and hold
federal and state take authorizations.
Sponsor subregional funding efforts required to implement the MHCP and cooperate in
development of any proposed regional funding effort.
Assure autonomy of participating cities.
Appoint any required science advisors.
Serve as the Board of Directors of an MHCP Land Conservancy if one is formed.
Assure that participating cities with implementing agreements are fully coordinating their
management, monitoring, and maintenance plans through the activities of the MHCP Staff
Subcommittee. The Elected Officials Committee shall develop and sponsor a memorandum of
agreement (MOA) or other similar equally effective process among the cities to assure
coordination of MHCP implementation actions.
The Elected Officials Committee will appoint an MHCP Advisory Committee to provide a forum for
coordinating MHCP implementation. The MHCP Advisory Committee will be divided into two
subcommittees: The MHCP Staff Subcommittee and the MHCP Stakeholders Subcommittee. The
Elected officials Committee may also oversee an MHCP Land Conservancy and serve as the Board of
Directors for such a conservancy. The Staff Subcommittee will ensure implementation of the subarea
plans are coordinated and provide recommended actions for management and funding are provided to
the Elected Officials Committee. The Stakeholders Committee will implement public outreach and
education and provide recommended funding sources to the Elected Officials Committee. The roles of
each of these parties and their relationship among each other is more fully described in section 5 of
Volume 1 of the MHCP.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 19
The HMP
-
The HMP proposes a comprehensive, citywide, program to identify how the City, in cooperation with
federal and state Wildlife Agencies, will preserve the diversity of habitat and protect sensitive
biological resources within the City while allowing for additional development consistent with the
City’s General Plan, it’s Local Coastal Plan, and its Growth Management Plan. The City’s plan is
within the umbrella of the MHCP, however, issuance of a permit to the City would stand independent
of the other participating cities draft subarea plans.
The City of Carlsbad proposes to create a preserve system to mitigate the impact of public and private
development over a 50-year period by protecting 6,786 acres (6,478 acres within the City of Carlsbad
and 308 outside the City of Carlsbad) of habitat for the Covered Species. The majority of the preserve
(5,928 acres) consists of existing and proposed “hard-line&’ areas designated for 100 percent
conservation. Up to 550 acres would be conserved on lands designated as “standards” areas which
have established assured levels of conservation through applying biological criteria (rather than
delineating the project footprint by a hard-line). An additional 307.6 acres would be conserved outside
of the City of Carlsbad’s Subarea to help offset impacts that would occur within the City’s Subarea
and outside of the City, but within the MHCP planning area.
Total conservation within the MHCP Preserve, as a result of the City’s HMP, is estimated to be 6,786
acres. The preserve within the City’s Subarea would contain, at a minimum, the following habitats:
coastal sage scrub (2,139 acres), chaparral (676 acres), southern maritime chaparral (342 acres),
grassland (707 acres), oak woodland (24 acres), eucalyptus woodland (99 acres), marsh (1,252 acres),
riparian (494 acres), and other non-habitat lands (745 acres).
In addition, the MHCP and the HMP include measures to avoid and minimize adverse affects to the
Covered Species, emphasizing project design modifications to protect both habitats and individual
species. A monitoring and reporting plan would gauge the Plan’s success based on achievement of
biological species objectives and reserve design criteria, and would ensure that conservation keeps
pace with open space conversion. The MHCP and the HMP also include adaptive management which
allows for changes in the conservation program if the biological species objectives are not met, or new
information becomes available to improve the efficacy of the MHCP’s and HMF”s conservation
strategy.
Approximately 35 percent of the City is within the designated Coastal Zone. The Coastal Act and the
City’s Local Coastal Program (LCP) regulate development within this area. The LCP has been
amended to include conservation standards for properties in the Coastal Zone as described later in this
section.
As described above in the MHCP section, a BCLA and FPA were identified in the City. The FPAs
were broken down into the HMP cores, linkages and Special Resource Areas which are shown and
identified on Figure 4 of the HMP. These areas include eight core WAS that are connected to one
another and to habitat areas outside the City, by a variety of linkages and wildlife movement corridors.
A description of the core and linkage areas is provided below:
Core and Linkage FPAs
1. Core 1 FPA: The Core 1 FPA, approximately 206 acres in area, consists of Buena Vista
Lagoon and adjoining wetland and upland habitats in northwest Carlsbad. This Core
FPA is dominated by open water and riparian habitats. Core 1 is connected to Core 2
via Buena Vista Creek, which is partially outside of Carlsbad in the City of Oceanside.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 20
2. Core 2 and Linkage FPAs: The FPA for Core 2 is located in the northeastern portion of
the City and is approximately 352 acres in area. It contains major grassland and
riparian habitats with scattered patches of chaparral and coastal sage scrub. Buena Vista
Creek borders the northern edge of Core 2 and supports riparian scrub and freshwater
marsh habitats. Core 2 has linkages to Core 3 (Linkage Area A), Core 4 (Linkage Area
B), and the City of Oceanside. The portion of Linkage Area B connecting Cores 2 and
4 is dominated by grassland and coastal sage scrub. It is approximately 1 mile in length
and about 300-400 feet wide, on average. Three roads, including El Camino Real, cross
this linkage. Core 2 also provides the only linkage from Carlsbad into Oceanside.
3. Core 3 and Linkage WAS: The Core 3 FPA (approximately 1,164 acres) contains large
areas of coastal sage scrub that support critical populations of gnatcatcher and thread-
leaved brodiaea. Major stands of chaparral and grassland are also present. The
northern portion of Core 3 contains open water, freshwater marsh, and riparian scrub
habitats that are associated with Lake Calavera. Oak woodland, riparian forest, and
riparian scrub occur in the southern section of this Core. Core 3 has linkages to Core 2
(Linkage Area A; see above), Core 4 (Linkage Area B), and Core 5 (Linkage Area C).
The portion of Linkage Area B between Cores 3 and 4 supports grassland and coastal
sage scrub communities that are surrounded by agricultural lands. The linkage is
approximately 3,000 feet long. Linkage Area C, between Cores 3 and 5, is a stepping-
stone linkage; it is approximately 0.5 mile long and contains small fragments of coastal
sage scrub surrounded by agricultural lands.
4. Core 4 and Linkage FPAs: The Core 4 FPA, (approximately 1,063 acres), located in
west-central Carlsbad, includes Agua Hedionda Lagoon and upland habitats
immediately east of the lagoon. Critical vegetation communities within this Core
include saltmarsh, freshwater marsh, and riparian scrub. Major areas of coastal sage
scrub are also present, as are small patches of grassland, southern maritime chaparral,
southern mixed chaparral, and coastal sage scrublchaparral. Core 4 has linkages to
Core 2 (Linkage Area B, see above), Core 3 (Linkage Area B, see above), Core 6
(Linkage Area F), and Core 8 (Linkage Area F). The portion of Linkage Area F
between Cores 4 and 6 is an approximately 1.5-mile stepping-stone linkage containing
moderately fragmented coastal sage scrub and grassland habitats. The portion of
Linkage Area F between Cores 4 and 8 is a stepping-stone linkage through west-central
Carlsbad containing fragmented patches of coastal sage scrub, grassland, and chaparral,
but also a significant amount of existing development. The linkage is approximately
2.5 miles long and is bisected by Palomar Airport Road.
I
5. Core 5 and Linkage FPAs: The Core 5 FPA is approximately 884 acres in area and is
located along the eastern border of Carlsbad in the central section of the City. This area
supports critical stands of riparian forest and southern maritime chaparral. It also
supports a large upland area of chaparral, chaparrallcoastal sage scrub, coastal sage
scrub, southern maritime chaparral, and grassland. Core 5 has linkages to Core 3
(Linkage Area C, see above), Core 6 (Linkage Area D), and Core 7 (Linkage Area D).
The portion of Linkage Area D between Cores 5 and 6 is approximately 3.0 miles long
and includes coastal sage scrub, chaparral, grassland, and riparian habitats. Portions of
this linkage include habitats in the neighboring city of San Marcos. The portion of
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 21
Linkage Area D between Cores 5 and 7 is approximately 3.0 miles long and contains
coastal sage scrub, chaparral, and grassland habitats. The southern portion of this
linkage includes areas in the neighboring city of San Marcos.
6. Core 6 and Linkage WAS: The Core 6 FPA (approximately 1,134 acres), contains a
critical stand of southern maritime chaparral and a major stand of grassland. It also has
several vernal pools. Core 6 has linkages to Core 4 (Linkage Area F, see above), Core
5 (Linkage Area D, see above), Core 7 (Linkage Area E), and Core 8 (Linkage Area F).
Linkage Area E connects Cores 6 and 7 and is a grassland corridor approximately 0.5
mile long and 300-400 feet wide with narrow north-south canyons vegetated with
coastal sage scrub. The portion of Linkage Area F connecting Cores 6 and 8 is a
stepping-stone linkage primarily for birds. It is approximately 1 mile long and consists
of coastal sage scrub and chaparral habitat patches.
7. Core 7 and Linkage FPAs: Core 7 is located along the eastern border of Carlsbad in the
southeast section of the City and is approximately 1,429 acres in area. Other habitats in
Core 7 include grassland, riparian scrub, and major stands of chaparral. Core 7 has
linkages to Core 5 (Linkage Area D, see above), Core 6 (Linkage Area E, see above),
and areas southeast of Carlsbad. The linkage between Core 7 and natural lands
southeast of the City contains large areas of chaparral and gnatcatcher-occupied coastal
sage scrub. In addition to landscape linkages, two wildlife movement corridors connect
Core 7 to Core 8. Coastal sage scrub, grassland, and channelized riparian areas along
the southern border of Carlsbad and the La Costa Country Club Golf Course exist
between these two Cores.
8. Core 8 and Linkage FPAs: The Core 8 PA, located in the southwest comer of
Carlsbad, includes Batiquitos Lagoon and Green Valley. It is approximately 1,129
acres in area. Critical vegetation communities in the area are maritime succulent scrub,
saltmarsh, and southern maritime chaparral. Core 8 has linkages to Core 4 (Linkage
Area F, see above) and Core 6 (Linkage Area F, see above). Two additional wildlife
movement corridors, not considered to be landscape-level linkages, connect Core 8 to
Core 7 (see above).
SDecial Resource Areas
Three naturally vegetated areas were too small, edge-affected, or isolated to be considered biological
Cores or linkage areas, but were considered important to preserve design or the conservation of
particular species and are characterized as Special Resource Areas (SRAs).
1. SRA 1 lies between El Camino Real, Faraday Avenue, and College Boulevard within Zone 5.
It is comprised of slopes covered by grasslands and small patches of coastal sage scrub.
2. SRA 2 includes the Poinsettia Lane vernal pools and their watershed.
3. SRA 3 is comprised of those portions of Encinitas Creek and its tributaries that are within Zone
11, including the natural vegetation adjacent to the drainages. The primary biological function
for this SRA is maintenance of wildlife movement between Batiquitos Lagoon (Core 8) and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 22
more inland biological Cores (e.g., Core 7 and undeveloped areas in the unincorporated
County) . -
Components of Preserve System
Using the FPAs and SRAs as a foundation, the HMP has identified a preserve system that consists of
existing hardline preserve areas, proposed hardline preserve areas, standards areas, and preservation in
the MHCP gnatcatcher core area, as described in the HMP and summarized below. It is expected that
the MHCP’s conservation goals can be met without acquisition of habitat lands. However, the State
and Federal Governments have committed to pursue acquisition of lands identified as priority 1
properties described in the Subregional MHCP Plan portion of this project description.
The HMP will not include City acquisition of privately-owned habitat lands within the City unless the
City chooses to acquire land or mitigation credits to provide additional mitigation for public facility
projects. The Preserve will be assembled primarily through the development entitlement process and
project processing will not deviate from the normal City process in most instances. However, projects
that are located in standards areas will require additional consultation with the City and the Wildlife
Agencies to determine whether the proposed project complies with the standards, as discussed in
Section D of the HMP, and a consistency finding with the HMP before they can proceed through the
normal City review process.
Figure 30 of the HMP shows the HMP compliance process and the difference between proposed
projects located within hardline areas versus standards areas. The details for processing a project in a
standards area are provided below (under Amendments to the HMP) and will require coordination
with, and concurrence by, the Service and Department regarding compliance with the standards.
Amendments would occur for the following reasons: minor Changes to the maps showing boundaries
of the Plan area or existing or proposed hardline areas; conversion of standards areas to hardline areas;
and possible future additions to the list of Covered Species. To facilitate the processing of such
changes, a HMP amendment process is described in detail in the HMP. For minor amendments this
includes equivalency findings and consistency findings.
Major amendments would occur for the following reasons: removal of lands from conserved areas,
reconfiguration of hardline areas resulting in a decrease of acreage or quality of habitat, and additions
to the Covered Species list. Major Amendments shall require environmental review and will be
subject to the amendment process as described in the HMP.
The City has identified numerous City projects in Appendix B of the HMP which are intended to be
permitted under the HMP. These projects include drainage projects, park facilities, sewer projects,
street projects, and water projects. The following City projects are addressed in the HMP by means of
proposed hardline preserve areas: the City’s municipal golf course, Lake Calavera, Veteran’s
Memorial Park, and Zone 19 Park. However, a majority of the projects which are all listed in
Appendix B, are not described in detail in the plan and could only proceed once a Consistency Finding
is made with the concurrence of the Wildlife Agencies. The Consistency Finding will ensure that the
projects are avoiding, minimizing and mitigating impacts to MHCP species according to the HMP and
MHCP standards. Some of the street projects are major roadways that bisect designated and proposed
preserve lands, such as, the extension of Marron Road and Cannon Road reach 4.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 23
Existing Hardline Preserve Areas
These areas include both publicly-owned land and privately-owned land that has been committed to
habitat conservation as a result of existing open space regulations, past development approvals, or
other actions'. This includes the City's three coastal lagoons and wetlands, the Dawson Los Monos
Reserve, as well as preserve areas in Aviara, Villages of La Costa, Rancho Carrillo, Calavera Heights,
Rancho Verde, Villages of La Costa, Carlsbad Highlands Conservation Bank, and other development
areas. Total acreage of existing hardline areas equals approximately 4,459 acres, or approximately
69% of the 6,449 acre preserve system (see Figure 5 and Table 4 of the €IMP). Since the publication
of the Carlsbad HMP the following projects have been approved by the Wildlife Agencies either
through formal consultation with the U.S. Army Corps of Engineers under section 7 of the Act or
through a permit under section 4(d) of the Act: Manzanita Properties, Bressi Ranch, Carlsbad Oaks
North Business Park, the Raceway Property, and Palomar Forum. In addition, the Kellymartman
property has completed the CEQA process and received its development permits from the City. No
federal or state listed species occurred on-site, so no permits from the Service or Department were
required. Thus, these projects are now within the baseline of effects and not analyzed within this
biological opinion because they have previously been approved and preceded this analysis. Please
note that Table 8 of the Carlsbad HMP may not have been updated to reflect that these projects have
been approved and/or completed, however, the total acreage figures of preservation in the City should
remain accurate.
-
ProDosed Hardline Preserve Areas
A number of proposed public and private projects have coordinated with the City, Service, and
Department and reached agreement on hardline designs for their projects. Once the City receives a
section 10(a)l(B) permit under the Act and initiates the HMP process, these proposals will obtain the
same conservation status as the existing hardline areas and the City's General Plan will be amended to
designate them as open space.
Habitat loss will be authorized for the remaining portions of the projects. These projects include Aura
Circle (as depicted in Addendum 2 of the HMP), Roesch (as depicted in Addendum 2 of the HMP),
Carlsbad Promenade (as depicted in Addendum 2 of the HMP), Redeemer by the Sea (as depicted in
Addendum 2 of the HMP), Thompson-Tabata (as depicted in Addendum 2 of the HMP), Summit (as
revised by Addendum 2 of the HMP), Mandana (as revised by Addendum 2 of the HMP), the City's
municipal golf course (as revised by Addendum 2 of the HMP), Lake Calavera, Veteran's Memorial
Park, Hub Park (as revised by Addendum 2 of the HMP), Zone 19 park, SDG&E south shore
properties, Holly Springs, Kelly Ranch (as revised by Addendum 2 of the HMP), South Coast, Hieatt
(as revised by text in Addendum 2 of the HMP), Shelley, Cantarini, and Kevane (as revised by
Addendum 2 of the HMP).
The general location of the proposed hardline areas are shown on the Revised Figure 6 of the HMP,
Addendum 2, while detailed boundaries are shown for the individual projects on Figures 7 through 25
and in Addendum 2 of the HMP. The proposed hardline boundaries on Veterans Memorial Park which
provides a corridor between the City's Municipal Golf Course and properties to the north, constitutes
mitigation for the development of the remaining portion of Veterans Memorial Park. A pedestrian
trail, park road and five individual and two group passive picnic areas will be permitted in the corridor.
The proposed hardline on Fox-Miller will not meet the conditions for coverage of brodiaea filifolia
due to the recent identification of 19,100 brudiaea filifolia plants on the property. Thus, modification
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 24
of this hardline would need to occur for coverage of brodiaea filifolia (see species analyses for
B rodiaea j?l ifor ia) . -
The City is proposing to include the 266-acre public property at Lake Calavera as a public project
mitigation bink for municipal projects such as mitigation a portion of the City's proposed municipal
golf course and the major roads shown on the City's Circulation Plan. The other City projects which
could be covered by the City mitigation bank are identified in Appendix B of the HMP. One of the
key objectives of the HMP is permitting for City public facility projects mandated by the Growth
Management Plan. The purpose of a public mitigation bank will be mitigation of unavoidable impacts
to biological resources resulting from these public facilities projects. There may be approximately
266.1 acres available at Lake Calavera. However, a formal mitigation bank agreement has not been
entered into among the Wildlife Agencies and the City. Such an agreement would be necessary for the
City to proceed with this action.
The levels of conservation achieved by the proposed hardline component of the preserve system by
habitat type and by Local Facilities Management Zones are provided in Table 6 of the HMP. The total
acreage of conserved habitat resulting from the proposed hardline conservation areas is 1,474 acres or
approximately 22 percent of the preserve system.
Standards Areas
For some key properties within the City that have not submitted proposed hardline designs for
inclusion in the preserve system at this time, the HMP includes conservation goals and standards that
will apply to future development proposals in these areas. The goals and standards have been arranged
according to the Local Facilities Management Zones to which they apply. The Carlsbad HMP
Planning Area is divided into 25 Local Facilities Management Zones (LFMZ) for planning purposes.
The LFMZs are not based on biological criteria, but are used throughout the HMP document for
conservation planning purposes. Figure 26 shows the LFMZs, the areas of the City and individual
properties covered by the standards areas.
The standards apply only to those areas within the LFMZs not already covered by existing and
proposed hardline areas, existing take authorizations or areas shown as development areas on the HMP
map. If individual properties are proposed for development within a zone, the property owner must
show how the standards will be met. Standards are identified for properties in zones 1,2, 8, 14, 15,20,
21 and 25.
The discussion of biological issues and goals is followed by standards for planning new developments
within each zone. These planning standards are intended to achieve the zone-specific biological goals
based on zone-specific conditions and constraints. They would be used during the land use planning
and review process by the City as described in Sections D and E of the HMP to identify conservation
priorities and compliance options for new projects. Although the standards will ultimately result in
determining preserve boundaries, the standards as well as the mitigating measures and ratios contained
in Tables 9 and 11 of the HMP apply to all projects in the zone whether they are within or outside the
preserve boundaries. (See page D-77 of the HMP for further discussion of Citywide minimization and
mitigation requirements.)
There are several properties within the standards areas that allow 25 percent of the property to be
developed in the least environmentally damaging location, while 75 percent will be conserved. The
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 25
Standards Areas will conserve an overall 67 percent of coastal sage scrub, as well as 75 percent of
gnatcatchers. Some zones may conserve more or less than these percentages due to parcel size,
location, resources, or long-term conservation potential. However, the City will ensure that, when
totaled throughout the City, an overall 67 percent of coastal sage scrub and 75 percent of gnatcatchers
will be presirved in the standards areas. The procedures detailed in Section E of the HMP will be
implemented in the processing of any application for development entitlements for the Standards
Areas. Implementation of Section E will ensure that the acreage goals and species preservation goals
outlined for the Standards Area will be achieved. The above standards would be applied to the
specified areas at the time of application for development entitlements. The procedures detailed in
Section E of the HMP will ensure that the conservation goals for the Standards Areas overall will be
achieved.
LFMZ-sDecific conservation standards
1. Zone 1: There are two specific areas within Zone 1 which specific standards are being
applied; several vacant lots on the north shore of Agua Hedionda Lagoon and a larger,
vacant in-fill lot located to the southwest of El Camino Real and Kelly Drive.
Avoid removal of maritime succulent scrub and any patches of coastal sage scrub in, or
contiguous with, biological core areas. Preserve at least 50 percent of coastal sage
scrub with a preference for avoidance of any areas that contain gnatcatchers. If impacts
to native habitats cannot be avoided, mitigate by creation or enhancement of like
habitats adjacent to lagoons, or by offsite compensation or restoration within biological
core and linkage areas. Maximize the preservation of habitat adjacent to the lagoon.
2. Zone 2: There are only two properties within this zone where specific standards would
apply. The first property is known as the Spyglass property located off the southeast
comer of El Camino Real and Carlsbad Village Drive. Although this property is not
contiguous to any other habitat and would not provide a link or corridor for habitat
connectivity purposes, a majority of the property contains native grasslands. This
property has been developed and mitigated all grassland impacts by native grassland
restoration offsite at the Carlsbad Highlands Mitigation Bank at a ratio of 2: 1. The
second property is the Kellymartman property which has completed the CEQA process
and received its development permits from the City. This project, when analyzed under
CEQA did not meet the planning standards in the HMP, but it proceeded prior to the
plan and no federal or state listed species occurred on-site. Thus, no permits from the
Service or Department were required and these projects are now within the baseline of
effects and not analyzed within this Opinion because they have previously been
approved and preceded this analysis. Please note that Table 8 of the Carlsbad HMP
may not have been updated to reflect that these projects have been approved and/or
completed. However, the acreage totals provided in Table 8 of the HMF' should remain
accurate.
Restoration of habitat is required in the northern portion of this zone, adjacent to
Ehghway 78.
3. Zone 8: There are two properties within this zone that are designated as standards
areas: the Kirgis property and the Callaghan property. Both properties are required to
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 26
avoid impacts to any identified Narrow Endemic plant populations. Impacts to coastal
sage scrub and southern maritime chaparral habitats shall also be avoided, with impacts
limited to smaller fragments, edges, lower quality areas, and areas devoid of sensitive
species. The Kirgis property shall be allowed a maximum of 25 percent of the parcel
for development purposes. The Callaghan property shall be allowed a maximum of 50
percent of the parcel for development purposes. Both properties shall place their
development on the least environmentally sensitive portion of the property.
Development of the Callaghan property shall be required to preserve Open Space as
shown on the certified Open Space Map for Planning Area L approved by the California
Coastal Commission as part of its action on LCP Amendment No. 2 - 99D (Kelly
Ranch).
4. Zone 14: Areas of upland habitat outside of the designated linkage B may be taken in
exchange for restoration and enhancement inside the linkage, as long as the result is
conservation of at least 67 percent of coastal sage scrub and the associated gnatcatcher
population within the southern portions of the zone. Creation of the linkage must
utilize patches of existing habitat within the identified alignment. Where consistent
with creation of Linkage B, avoid removal of natural habitats that are contiguous with
open space on adjacent parcels. Maintain and enhance the wildlife movement potential
between core areas using sensitive design of any road or utility crossings of Linkage B
(e.g., bridging, undercrossing). Conserve all riparian habitats onsite, and prohibit fill or
development within the existing flood plain except where required for Circulation
Element roads, Drainage Master Plan facilities, or other essential infrastructure, unless
otherwise agreed to by the Wildlife Agencies. Conserve any Narrow Endemic plant
populations identified during planning. When conversion of agricultural lands to other
uses is proposed, set back all development impacts at least 100 feet from existing
wetland habitats and require habitat restoration or enhancement in the riparian and
buffer areas.
5. Zone 15: Maintain and enhance a habitat linkage across Linkage Area C and adjoining
portions of Core Areas 3 and 5 that averages between 500 and 1,000-feet wide, with a
minimum width of no less than 500 feet. Emphasis will be on improving gnatcatcher
habitat within the linkage. Areas of upland habitat outside of the designated linkage
Area C may be taken in exchange for restoration and enhancement inside the linkage, as
long as the result is no-net-loss of coastal sage scrub and the associated gnatcatcher
population within the southern portion of the zone. Creation of the linkage must utilize
patches of existing habitat within the identified linkage alignment. Where consistent
with the creation of Linkage C, avoid removal of natural habitats that are contiguous
with open space on adjacent parcels. Maintain and enhance the wildlife movement
potential between core areas using sensitive design of any road or utility crossings of
Linkage C. Conserve all riparian habitats onsite, and prohibit fill or development
within the existing flood plain except where required for Circulation Element roads,
Drainage Master Plan facilities, or other essential infrastructure. Conserve any Narrow
Endemic plant populations identified during planning. When conversion of agricultural
lands to other uses is proposed, set back all development impacts at least 100 feet from
existing wetland habitats and require habitat restoration or enhancement in the riparian
and buffer areas.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 27
6. Zone 20: Conserve habitats in a continuous configuration through Linkage Area F,
from Core Area 6 to where Linkage Area F crosses Palomar Airport Road. This
configuration-is intended to allow for continued animal movement between core areas 4
and 6, particularly for gnatcatchers and other birds. The objective is to create
continuous habitat connectivity and wildlife movement across the zone with a minimum
constriction of 500 feet. However, in no case shall this standard deny a property owner
some reasonable use of their property. Areas of coastal sage scrub and maritime
succulent scrub outside of the designated Linkage F may be taken in exchange for
restoration and enhancement inside the linkage, as long as the result is no-net-loss of
these habitats or the associated gnatcatcher population within the standards portions of
the zone. Southern maritime chaparral outside of core and linkage areas may also be
taken unless it supports significant populations of Narrow Endemic plants (the narrow
endemic policy would need to be applied). Creation of linkage F must utilize patches of
existing habitat within the identified alignment. Where consistent with creation of
Linkage F, avoid removal of natural habitats that are contiguous with open space on
adjacent parcels. Maintain and enhance the wildlife movement potential between core
areas using sensitive design of any road or utility crossings of Linkage F. Conserve all
riparian habitats onsite, and prohibit fill or development within the existing flood plain
except where required for Circulation Element roads, Drainage Master Plan facilities, or
other essential infrastructure. When conversion of agricultural lands to other uses is
proposed, set back all development impacts at least 100 feet from existing wetland
habitats and require habitat restoration or enhancement in the riparian and buffer areas.
Mitigation for any allowed impacts shall be as stated in Table 9 of this biological
opinion (Table 11 in the HMP).
7. Zone 21: Additional field surveys at the appropriate time of year are needed in this
zone to determine the extent and location of sensitive species. Major areas for
development should be restricted to agricultural areas and disturbed habitat. Avoid
removing maritime succulent scrub, southern maritime chaparral, and any Narrow
Endemic plant populations identified during planning. Minimize removal of coastal
sage scrub and southern maritime chaparral; avoid impacts within the watersheds of
vernal pools and to oak riparian forest. Ensure continuous habitat connectivity and
wildlife movement east-west across the zone with an average habitat width of 500 feet
to 1,000 feet and a minimum constriction of 500 feet (where narrower constrictions
don't already exist). However, in no case shall this standard deny a property owner
some reasonable use of their property. If impacts to natural habitats cannot be avoided,
they must be limited to disturbed, low quality portions of the site. Areas of highly
disturbed, low quality southern maritime chaparral and coastal sage scrub may be
mitigated by a combination of onsite enhancement and offsite mitigation in locations of
higher quality habitat. Mitigation for any allowed impacts shall be as stated in Table 9
of this biological opinion (Table 11 in the HMP).
8. Zone 25: Conservation of approximately 75 percent of the Sherman property is
required to provide adequate connectivity within the regional gnatcatcher corridor. The
percentage of conservation can be modified with the concurrence of the Wildlife
Agencies as long as conservation planning goals can be achieved. Align future Marron
Road to minimize impacts to sensitive biological resources and disruption of wildlife
movement. Conserve wetland habitats and set development back at least 100 feet.
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 28
Avoid and minimize removal of coastal sage scrub and maintain a continuous linkage
of sage scrub, chaparral, and grassland averaging 800 feet to 1,000 feet wide along the
southern and western portion of the zone with a minimum constriction of 500 feet
where narrower constrictions do not already exist. Mitigate any removal of natural
habitat by onsite restoration or enhancement of coastal sage scrub to improve
gnatcatcher breeding habitat within the zone. Conserve any Narrow Endemic plant
populations. Conserve and enhance riparian vegetation along Buena Vista Creek with
200-foot buffers supporting natural vegetation between wetland habitats and
development. Prohibit fill or development within the existing 100 year flood plain
except where required for Circulation Element roads, Drainage Master Plan facilities, or
other essential public infrastructure. Use sensitive design of any road or utility crossing
of Buena Vista Creek. Mitigation for any allowed impacts shall be as stated in Table 9
of this Opinion (Table 11 in the HMP).
The City’s projection of levels of conservation within the preserve system achieved by future
compliance with the conservation standards by habitat type and by LFMZ are provided in Table 7 of
the HMP. The total estimated acreage of conserved habitat resulting from the proposed standards
areas is 553 acres or approximately 9 percent of the preserve system. It should be noted that the
acreage figures are an estimate based on the information currently available. Precise figures for any
specific area will not be known until completion of the review and approval process described above.
Restoration of Coastal Sage Scrub in the Citv
Restoration of 104 acres of coastal sage scrub will occur in key locations within the City’s FPA. The
purpose of the restoration is to increase breeding habitat for the gnatcatcher and improve functionality
of a “stepping-stone” linkage through the MHCP plan area. The key locations identified were on the
Carlsbad Raceway, Robertson Ranch, and the City’s proposed municipal golf course. The Carlsbad
Raceway has since been approved under formal consultation with the US. Army Corps of Engineers
under section 7 of the Act. The applicant has committed to restoration of 17.5 acres of coastal sage
scrub restoration associated with this project. In addition, coastal sage scrub restoration will occur
onsite at the adjacent Palomar Forum (1.57 acres) and Carlsbad Oaks North (20.9 acres) projects. The
Robertson Ranch site is expected to have 10 acres of coastal sage scrub revegetation associated with
the Calavera Hills project and an additional 21 acres of coastal sage scrub revegetation associated with
developing the Robertson Ranch parcel. The City’s proposed municipal golf course has since
increased the amount of on-site revegetation of coastal sage scrub by 15.4 acres, however, this
restoration credit is being deducted from the City’s obligations in the gnatcatcher core area as
described below. In addition, the Carlsbad Oaks North project will be restoring 20 acres of nonnative
grasslands to coastal sage scrub offsite at the Carlsbad Highlands mitigation bank. Thus, shortly after
receiving their permit for the HMP, the City is expected to meet and exceed the 104 acres of coastal
sage scrub revegetation expected in section 3.3.2 of MHCP Volume 1.
Preservation in the MHCP Gnatcatcher Core Area
As stated earlier, it was determined through the analysis of biological viability of the proposed
preserve system that a large (approximately 500 acre), biological core area that supports a population
of 16 to 23 gnatcatchers was needed in the MHCP planning area. As a result, an area located in the
unincorporated County between San Marcos, Carlsbad, and Encinitas was identified where such
preservation should occur and is referred to as the MHCP gnatcatcher core area (see Figure 3-3 in
Carlsbad Subarea Plan, Biological and Conference Opinions (FWS-SDG-847.4) 29
Volume 1 of the MHCP). In addition, as part of the approval of the Fieldstone HCP, the City was
required to take a lead position in identifying the location and potential funding sources for 240 acres
in the MHCP core area. In order to fulfill its obligation to conserve gnatcatcher habitat in the MHCP
core area, increase conservation levels for the gnatcatcher in the HMP, and to fulfill its responsibilities
under the Fi6ldstone HCP, the City committed to effectuate the conservation and conveyance of 307.6
acres of land within the MHCP core area which consists of the following components:
1. 227.96 acres of CSS was needed to be preserved offsite by the City and developer in
association with the Fieldstone HCP (as explained below).
2. 20 acres of CSS was preserved offsite for the Rancho Carrillo development by purchase of the
Nelson property. The Nelson property has been conveyed in fee title to the Center for Natural
Lands Management and the Department is currently reviewing a draft conservation easement
by which it would be granted a conservation easement on the property.
3. 12 acres of additional CSS was preserved onsite at Villages of La Costa.
4. 47.64 acres of CSS is to be preserved by the City (not associated with the proposed municipal
golf course). The City has committed to instituting an in-lieu fee program to acquire this
acreage.
This obligation is also described in Section D of the HMP. However, the description provided in this
Opinion is more up-to-date as described below. One such change is that the City’s 47.64 acre
obligation for preservation by the City has decreased due to an increase in conservation beyond which
was expected in the City when the 307.6 acre need was identified. These additional conservation
actions include the following: 1) additional conservation of 11.79 acres of coastal sage scrub on-site at
Villages of La Costa; 2) an additional 25 acres Citywide mostly as a result of softline or hardline
projects being permitted prior to this permit but resulting in greater conservation than assumed in the
HMP; and 3) a 15.4 net acre increase of coastal sage scrub revegetation on the City municipal golf
course. Thus, the City’s 47.64 acre obligation no longer exists since the additional conservation listed
in items 1,2, and 3 total 52.19 acres. In fact, the City has a 4.55 acre credit which can be applied to
their portion of the 227.96 acre obligation.
The 227.96 acre obligation associated with the Fieldstone HCP is not solely the City’s obligation.
Morrow Development (successor to Fieldstone La Costa Associates) had an obligation to purchase
land valued at one million dollars. This money went to the purchase of 18.02 acres and 21.37 acres of
land on a parcel named Alemir. The remaining acreage, (227.96 - 39.39) 188.57 acres, is the
responsibility of the City to effectuate the conservation and conveyance within the MHCP gnatcatcher
core area. However, to ensure that at least most of the acre obligation in the gnatcatcher core area was
available for conservation, Morrow Development purchased 113.94 acres of land known as the
Choumas-Pappas parcel and the entire 114.02 acres of land known as the Alemir parcel within the
general area of the gnatcatcher core area. The properties have been conveyed in fee title to the Center
for Natural Lands Management. A conservation easement in favor of the Department is being
recorded. This land was set aside in a similar fashion to an informal mitigation bank. Because
Morrow Development’s only obligation was to fund 1 million dollars, of which 39.39 acres on Alemir
was purchased. Some City projects have mitigated on the land purchased by Morrow Development:
1) Bressi Ranch (24.5 acres on Alemir), and 2) the Palomar Forum (1.7 acres on Choumas-Pappas and
Carlsbad Subarea Plan Biological and Conference Opinions (F’WS-SDG-847.4) 30
3.2 acres on Alemir). In addition, the City has reserved 51.6 acres of land at Choumas-Pappas to
partially mitigate for impactsfrom the City’s proposed municipal golf course (This acreage must
contain habitat occupied by five pairs of gnatcatchers). Because these projects were within the City
these projects are appropriate to subtract from the City’s 188.57 acre outstanding obligation and the
4.55 acre of Eredit described earlier can be applied against this obligation. Thus, their outstanding
obligation has been reduced to 103.02 acres.
Thus, the City needs to cause to effect the conservation with funding for management and monitoring
in perpetuity 103.02 acres of CSS in the City or gnatcatcher core area to fulfill this obligation. Our
current understanding is that the City intends to reimburse Morrow Development for the remaining
acreage on Alemir (46.93 acres) and if there is any remaining acreage on Choumas-Pappas (estimated
to be approximately 3.6 acres) and find a separate parcel in the City or gnatcatcher core area for the
remaining 52.49 acres, for which the in-luie-fee program would be used. However, should the City
not use Morrow Development land to meet their obligation, the City would need to ensure an equal
amount of acreage is preserved within the City in order not to have multiple impacts mitigated with
the same acre of land. The City could offset such occurrences through additional preservation within
the City or MHCP that is not already identified as required in the HMP or MHCP.
The City’s obligation to cause to effect conservation of CSS can be achieved by projects directly
associated with the City in some way mitigating on these lands. However, please note that Morrow
Development has no obligation to only sell to the City or for mitigation associated with projects that
occur within the City. To ensure the same piece of land is not used to off-set the environmental
impacts of two separate actions, if any such projects outside, and not associated with the City, mitigate
at Choumas-Pappas and/or Alemir by reimbursement to Morrow Development, such acreage could not
be subtracted from the City’s 103.02 acre obligation.
General
The total acreage estimated to be conserved through implementation of the HMP is shown on Table 3
of the HMP. As the HMP is implemented, conservation will occur within and outside the City. Land
conserved within the City will be conveyed into the Preserve. All land being conveyed will be
accompanied by a conservation easement or other mechanism approved by the Service and
Department as being sufficient to insure that lands are protected in perpetuity. Conservation outside
the City will occur within the MHCP gnatcatcher core area and will be conserved in accordance with
the conservation mechanisms identified in the MHCP.
Measures to Minimize Impact on HMP Species and Mitigation Requirements
The primary mitigation for impacts to HMP Species under the Plan is the conservation and
management of habitat for the species in the preserve system identified above. In addition, measures
to avoid and minimize impacts will apply citywide to all public and private projects both within and
outside the preserve system boundaries on a project level basis in compliance with the requirement of
the Act that the impacts of incidental take be minimized and mitigated to the maximum extent
practicable. The measures to avoid, minimize, and mitigate impacts and the conservation goals for
HMP species are summarized in Table 9 of the HMP. Such measures include mitigation ratios for
impacts to natural habitats, narrow endemic standards, wetland conservation standards, and
conservation measures for natural habitats in the coastal zone. Some of the measures within Table 9
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 31
are similar to the MHCP conditions within Volume 2 of the MHCP. In any case where the conditions
differ, the condition which provides more protection to the species is that which is to be implemented. -
Mitigation Ratios for Impacts to Native Habitats
All future projects, including City public facility and improvement projects, shall mitigate impacts to
habitat based on the mitigation ratios provided in Table 9 below. Again, these mitigation ratios apply
whether a project is located inside or outside the preserve system. Projects that conserve at least 67
percent of habitat onsite shall not be subject to offsite mitigation unless they are located outside of the
BCLA. The premise of this standard is that if the habitat is outside of the BCLA it is not expected to
- provide any long term biological value (except possibly for narrow endemics if present). Thus, on-site
preservation for native habitat outside of the BCLA would be discouraged and any impacts to native
habitat which occurs on the property could not be mitigated by on-site preservation. Once again, if
inside the BCLA, habitat conserved onsite shall be credited toward mitigation. After determining the
amount of acreage needed for mitigation based on the mitigation ratios, the acres of onsite conserved
habitat shall be subtracted from the required acres of mitigation. Mitigation shall occur within the
City principally in the focus planning areas unless the City Council authorizes mitigation outside the
City. For habitat Groups D, E and F as identified on Table 9, a mitigation fee shall be paid to- the City
in lieu of offsite mitigation in an amount to be determined by the City Council. The amount of the fee
shall be adequate to cover the cost of any acquisition of land in the MHCP core area which is the
responsibility of the City of Carlsbad and for which funding has not previously been provided. The
fee may also be used to provide for overall management and maintenance of the preserve system. This
fee, and the process that the City will use to administer this fee, is discussed in more detail in the HMP
and IA.
The mitigation ratios for the HMP differ from the ratios within the MHCP. The MHCP allows cities
to adopt different policies and guidelines, if they demonstrate that the alternative policies and
guidelines contained in the cities’ subarea plans would achieve equivalent or greater levels of
conservation. The ratios provided in the HMP are lower for unoccupied coastal sage scrub and coastal
sage chaparral mix (1: 1 versus 2: 1). However, the HMP will achieve equivalent or possibly greater
levels of conservation because the same ratios apply regardless of impacts being within the FPA or
outside of the FPA and the ratios used are predominantly those recommended by MHCP for inside the
FPA. In addition, greater standards which include creation exist for impacts within the coastal zone as
described later.
Mitigation banks must be approved by the City and the Wildlife Agencies, subject to the issuance by
the City of a conditional use permit as required by the Carlsbad Municipal Code. City projects will
mitigate at the same ratios as private projects. However, City projects intend to use the Lake Calavera
Mitigation Bank for impacts to unoccupied coastal sage scrub, mixed chaparral, and annual
(non-native) grasslands once such a bank is formally created and implementing agreement is signed by
the Wildlife Agencies.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
A.
estuarine, salt padmudflak, riparian forest, riparian woodland,
riparian scrub, vernal pools, disturbed wetlands, flood channel,
fresh water Engelmann oak woodland, coast live oak woodland
Coastal salt marsh, alkali marsh, freshwater marsh,
Table 9 Mitigation Ratios for Impacts to HMP Habitats
No-net-loss goal (mitigation ratio varies by type of
replacement habitat)
Habitat Group and Type
B.
scrub, southern maritime chaparral, native grass
C.
D.
chaparral (excluding southern maritime chaparral)
Beach, southern coastal bluff scrub, maritime succulent
Gnatcatcher - Occupied coastal sage scrub
Unoccupied coastal sage scrub, coastal sagekhapmal mix,
Mitigation Ratiomequirement by Type of
Impacted Habitat
3:l (2)
2:1 (3)
1:l (4)
E. Annual (non-native) grassland 0.5:l (4)
F. Disturbed lands, eucalyptus, agricultural lands Mitigation Fee (4)
32
Footnotes:
1.
Clean Water Act or Section 1600 of the California Fish and Game Code.
Group A habitats are associated with wetlands. Impacts to these habitat types are subject to review under Section 404 of the federal
2.
quality southern maritime chaparral may be located outside a preserve area and maximum avoidance and onsite conservation is
preferred.
3.
4.
an amount to be determined by the City Council. This fee is discussed in more detail in Section E of the Plan.
5. These projects may mitigate out-of-kind because the objective is to build the preserve system by combining small mitigation
requirements into a larger, contiguous area. City projects that impact Type A, B, and C habitats must mitigate in-kind at the ratios stated
above.
It is assumed that all habitat types in Group B will be included in the proposed preserve system. Small, isolated patches of low
Maximum avoidance and onsite conservation of Group C habitat is encouraged.
Offsite mitigation for habitat in this group which is not conserved or mitigated onsite, shall pay a per acre in lieu mitigation fee in
City projects that impact Type D, E, and F habitats will not pay the fee and will mitigate at the Lake Calavera Mitigation Bank.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 33
Narrow Endemic SDecies Standards -
Narrow endemic species are taxa that are highly restricted by their hdbitat affinities, soil conditions
and/or other ecological factors, and as such, require additional measures to ensure that their long-term
viability is maintained. In addition to the requirements that apply to Habitat Types A-F on Table 8,
projects that would affect lands occupied by narrow endemic species must meet the following
conservation standards as described in section 3.7 of Volume 1 of the MHCP.
Both inside and outside the FPA, impacts to narrow endemic populations will be avoided to the
- maximum extent practicable while maintaining some economic or productive use of the property, as
supported by adequate facts. If the land is within the proposed hardline preserve system, 100 percent
conservation of the narrow endemic population(s) is required. In no case will the City permit more
than 5 percent loss of narrow endemic populations or occupied acreage within the FPA. If the land is
outside the FPA, at least 80 percent conservation of the narrow endemic population(s) is required.
Regardless of location, narrow endemic populations listed as “Critical” in Table 3-7 of Volume 1 of
the MHCP must be totally avoided, and any populations that are later discovered and determined to
meet the criteria for a critical population must be maximally avoided while allowing some economic
or productive use of property as supported by substantial factual evidence. Such determinations would
be made jointly by the City, California Department of Fish and Game, and the Service.
However, please note that the hardline for Fox-Miller will impact thread-leaved brodiaea greater than
permitted under the narrow endemic. The current hardline would impact at least 30 percent of the
population directly and significant indirect effects would occur to an additional 20 percent of the
population on-site. As a result, the City’s coverage for this species is conditioned on the hardline for
this project being changed to conform to the narrow endemic policy and management and monitoring
occurring to MHCP standards for the thread-leaved brodiaea preserved on-site. Please see the species
analysis for thread-leaved brodiaea for more details.
A composite list of the Narrow Endemics covered by this Plan is provided below by combining the
species listed in Table 10 of the HMP and Table 3-2 of the MHCP (Volume 1). As a result, the HMP
considers the following additional species as narrow endemics: short-leaved dudleya (Dudleya
variegata), Nuttall’s lotus (Lotus nuttallianus), oblivious tiger beetle (Cicindela Zatesignata obliviusa),
Harbison’ s dun slupper butterfly (Euphyes vestris harbisoni), coastal cactus wren (Campylurhynchus
brunneicapillus cuusei), and the Pacific little pocket mouse (Perugnathus lungirnembris pacificus).
The conservation goals and measures for such species within the City are indicated in Table 9 of the
HMP and sections 3-7 and 3-30 of the MHCP (Volume 1).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Plants
Acanthamintha ilicifolia
34
San Diego thorn-mint
Table 10: Combined MHCP and HMP Narrow Endemic Species List
Ambrosia pumila
Arctostaphylos glandulosa ssp. crassifolia
Baccharis vanessae
I - 1 i
San Diego ambrosia
Del Mar manzanita
Encinitas baccharis
I Scientific Name I Common Name I
Brodiaea fd$olia
Chorizanthe orcuttiana
Thread-leaved brodiaea
Orcutt’s spineflower
~ ~~
Corethrogyne filaginifolia var. linifolia
Dudleya blochmaniae ssp. blockmaniae
~
Del Mar Mesa sand aster
Blockman’s dudleya
Dudleya blockmaniae ssp. brevifolia
Dudleya variegata
Short-leaved dudleya
Variegated dudleya
Eryngium aristulatum var. parishii
Hazardia orcuttii
San Diego button-celery
Orcutt’s hazardia
~~ ~~ ~
Lotus nuttallianus Nuttall’s lotus/prostrate lotus
Muilla clevelandii San Diego goldenstar
~
Myosurus minimus ssp. apus
Navarretia fossalis
Orcuttia californica
Animals
State Fullv Protected Species
Little mousetail
Spreading navarretia
California Orcutt grass
Although fully protected species are included in the list of Covered Species, the hunting, pursuit,
catching, capturing, killing, or attempting to hunt, pursue, catch, capture, or kill these species is not
~
Streptocephalus woottoni Riverside fairy shrimp
Branchinecta sandiegonensis
Cicindela latesignata obliviosa
Lycaena hermes Hermes Copper
Euphyes vestris harbisoni
Campylorhynchus brunneicapillus cousei
Perognathus longimembris pacificus
San Diego fairy shrimp
Oblivious tiger beetle
Harbison’s dun skipper butterfly
Coastal cactus wren
Pacific pocket mouse ,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 35
authorized in the NCCP Permit and is prohibited by the California Fish and Game Code. The
following species in the HMP are fully protected under the California Fish and Game Code: (1)
California brown pelican; (2) American peregrine falcon; (3) Light-footed clapper rail; and (4) the
California least tern.
The Department acknowledges and agrees that if the measures set forth in the HMP are fully complied
with, the Covered Activities are not likely to result in take of these species. If the Department
determines that such measures are not adequate to prevent take of one of the fully protected species,
the Department shall notify the City in writing of such discovery and propose new, additional, or
different conservation measures that it believes are necessary to avoid take of these species. The City
shall implement the measures proposed by Department or other measures agreed to by the Parties as
adequate to avoid take of fully protected species. Therefore, we do not anticipate any take, including
harassment, of these species. Please see the species analysis section for each of these species.
Wetland Conservation Standards
The MHCP and HMP have a no-net loss standard for wetland functions and values. The City will
provide protection to Type A Habitats (riparian and wetland habitats, including vernal pools) as part of
the project review and approval process and the associated CEQA process. The Analysis of proposed
impacts to wetlands shall consist of a three-step process. The first step involves determining whether
the impacts are avoidable; the second step entails determining the allowable amount of encroachment
for unavoidable impacts; and the third step involves determining the mitigation for unavoidable
impacts.
All projects that would affect wetlands (Type A Habitats) must demonstrate that the impacts: 1) cannot
be avoided by a feasible alternative; 2) have been minimized to maximum extent possible; and 3) will
be mitigated in ways that assure no-net-loss of habitat value or function. This demonstration will
occur as part of the CEQA review for the project, will require documentation and analysis of impacts
and alternatives, and must include an evaluation of the value and function of the affected habitat.
The evaluation of habitat function and value will consider the rarity of the habitat type; presence of
listed and sensitive species; proportion of native to exotic vegetation; existing levels of habitat
disturbance; connection to or isolation from natural habitats and preserves; groundwater and water
quality issues; potential for restoration; feasibility of long-term management; and other relevant
ecological factors. Road or utility projects that must cross a wetland, shall demonstrate that the
crossing will occur at the narrowest andor least sensitive location and that all feasible minimization
measures have been employed. In malung this determination, alignment planning must consider
whether avoidance of wetland impacts would result in more significant upland impacts. Private
projects, that would impact a wetland, must demonstrate that the impact is essential to the feasibility of
the project and that no feasible alternative would eliminate or minimize the impact.
The specific location of mitigation lands will be determined in consultation with the Service, Corps,
and Department as appropriate in accordance with the requirements of the federal Clean Water Act,
federal wetland policies, and the California Fish and Game Code for all projects affecting Type A. All
mitigation lands for impacts to vernal pools, riparian and wetland habitats will be in the City or MHCP
plan area. The following wetlands mitigation ratios will be used (see Table 4-7 of Volume 1 of the
MHCP) .
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Wetland Vegetation Community
Coastal salt marsh
Alkali marsh
36
Mitigation Ratio
4: 1
4: 1
-
Table 11: Wetland Mrtigation Ratios I I
Estuarine
S altpadmudflats
4: 1
4: 1
~
Oak riparian forest 3: 1
Riparian forest 3: 1
Riparian woodland
Riparian scrub
Fresh water
Freshwater marsh
3: 1
1:1 to 2:l
1:l
1:l to 2:l
Flood channel
Disturbed wetlands
Irnalpool
1:l to 2:l
1:l to 2:l I 2:1 t04:l
The City does not anticipate that any substantial areas of vernal pool habitat occur in Carlsbad in
addition to those known and documented in the HMP. However, should additional vernal pools be
discovered, there would be a strong priority given to avoidance of impacts, followed by mitigation for
any unavoidable impacts. Any loss of vernal pool habitat would need to receive the concurrence of
the Wildlife Agencies. Please note that the Wildlife Agencies have already acknowledged that there
will be impacts to one vernal pool watershed on the Hiaett property if the hardline depicted and
modified by text in Addendum 2 of the HMP is implemented, thus, additional concurrence from the
Wildlife Agencies is not needed for this area. However, if additional impacts are proposed,
concurrence from the Wildlife Agencies would be required.
Impacts to highly degraded vernal pool habitat laclung sensitive species may be acceptable if the pools
are isolated from other vernal pool complexes, lack sensitive vernal pool species, exhibit low native
vernal pool species diversity, have low restoration potential, or would be infeasible to manage
effectively. In these cases, mitigation would need to provide no-net-loss of vernal pool area and
vernal pool habitat value, and mitigation would need to occur in the City.
In addition to the above requirements, a number of species are associated with Type A habitats. Thus,
all species-specific measures found in the HMP and Volume 2 of the MHCP, will be required of any
project that may impact the habitat of these species.
Additional standards are applied to those wetlands within the coastal zone as described below.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 37
Conservation Measures for Natural Habitats in the Coastal Zone
The City and HMP commit tb applying additional specific conservation measures for impacts that
would occur in the coastal zone. These measures include standards for wetlands, Environmentally
Sensitive Habitat Areas, native upland habitats, highly constrained properties, fuel modification,
grading and landscaping, and specific parcels as summarized below.
Wetlands
In addition to the wetland policy described in the previous section, wetlands in the coastal zone must
meet the following standards. Wetlands in the Coastal Zone shall be delineated following the
definitions and boundary descriptions in Section 13577 of the California Code of Regulations.
Pursuant to California Public Resources Code Section 30233, no impacts to wetlands shall be allowed
in the Coastal Zone except as provided in that Section. However, if impacts to a wetland are allowed
consistent with California Public Resources Code Section 30233 above, mitigation shall be provided at
a ratio of 3: 1 for riparian impacts and 4: 1 for saltwater or freshwater wetland or marsh impacts.
Environmentally Sensitive Habitat Areas
Pursuant to Section 30240 of the California Coastal Act, environmentally sensitive habitat areas
(ESHA), as defined in Section 30107.5 of the Coastal Act, shall be protected against any significant
disruption of habitat values, and only uses dependent on those resources shall be allowed within those
areas. However, where impacts to ESHA are allowed, mitigation shall be provided as follows:
1. The no-net-loss standard shall be satisfied as stated above. Typically this will consist of
creation of the habitat type being impacted (or substantial restoration where allowed) at
a ratio of at least 1: 1 as provided in the HMP.
2. Onsite preservation is not eligible for mitigation credit in the coastal zone. Onsite or
offsite open space preserve areas may be utilized to satisfy required mitigation for
habitat impacts associated with development if the preserve areas are disturbed and
suitable for restoration or enhancement, or they are devoid of habitat value and
therefore suitable for the 1 : 1 mitigation component requiring creation or substantial
restoration of new habitat. Substantial restoration is restoration that has the effect of
qualitatively changing habitat type and may meet the creation requirement if it restores
habitat type that was historically present, but has suffered habitat conversion or such
extreme degradation that most of the present dominant species are not part of the
original vegetation. Substantial restoration contrasts with enhancement activities
which include weeding or planting within vegetation that retains its historical character,
and restoration of disturbed areas to increase the value of existing habitat which may
meet other mitigation requirements pursuant to the HMP.
3.
4.
Impacts to Coastal Sage Scrub shall be mitigated at an overall ratio of 2: 1, with the
creation component satisfying half of the total obligation. The remainder of the
mitigation obligation shall be satisfied pursuant to the provisions of the HMP.
Impacts to Southern Maritime Chaparral or Maritime Succulent Scrub shall be
mitigated at an overall ratio of 3: 1, with the creation component satisfying one-third of
the total obligation. The remainder of the mitigation obligation shall be satisfied
pursuant to the provisions of the HMP.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 38
5. Impacts to Southern Mixed Chaparral, Native Grassland, and Oak Woodland shall be
mitigated respectively at ratios of 1 : 1 , 3: 1 , and 3: 1 , with the creation component
satisfying the obligation or one-third of the total obligation. The remainder of the
mitigation obligation shall be satisfied pursuant to the provisions of the HMP.
Mitigation for impacts within the coastal zone should be provided within the coastal
zone if possible, particularly the 1: 1 creation component, in order to have no-net-loss of
habitat within the coastal zone. Wtigation measures on land outside the Coastal Zone
may be acceptable if such mitigation would clearly result in higher levels of habitat
protection and value and/or would provide significantly greater mitigation ratios, and
the mitigation area is part of the HMP. Land area inside and outside the coastal zone
which serves as mitigation for habitat impacts in the coastal zone shall be permanently
retired from development potential and secured as part of the HMP preserve
management plan as a condition of development approval.
6.
7.
8.
Habitat mitigation requirements other than the creation or substantial restoration
component may be partially or wholly fulfilled by acquisition of existing like habitat
and/or retirement of development credits on existing like habitat with permanent
preservation as part of the HMP preserve management plan.
All mitigation areas, onsite and offsite, shall be secured with a conservation easement
in favor of the Wildlife Agencies. In addition, a preserve management plan shall be
prepared for the mitigation areas, to the satisfaction of the City, the Wildlife Agencies,
and the Coastal Commission. Phase I of the preserve management plan shall be
incorporated into the Implementation Program of the LCP through an LCP amendment
within one year of Commission certification of the HMF' as part of the certified LCP.
Phase 2 of the preserve management plan shall be incorporated into the Implementation
Program in the same manner within three years of Commission certification of the
HMP as part of the certified LCP. The preserve management plan shall ensure
adequate funding to protect the preserve as open space and to maintain the biological
values of the mitigation areas in perpetuity. Management provisions and funding for
mitigation required to address habitat impacts shall be in place prior to the impacts for
which the mitigation is required. At a minimum, monitoring reports shall be required
as a condition of development approval after the first and third year of habitat
mitigation efforts.
9. If any conflict should arise between the provisions of the HMP and the policies of the
LCP, the LCP shall take precedence.
Native UtAand Habitats
Properties containing coastal sage scrub located in the Coastal Zone shall conserve a minimum 67
percent of the coastal sage scrub and 75 percent of the gnatcatchers onsite. Conservation of
gnatcatchers shall be determined in consultation with the Wildlife Agencies.
In addition, there shall be no-net-loss of coastal sage scrub, maritime succulent scrub, southern
maritime chaparral, southern mixed chaparral, native grassland, and oak woodland within the coastal
zone of Carlsbad. Mitigation for impacts to any of these habitat types, when permitted, shall include a
creation component that achieves the no-net-loss standard. Substantial restoration of highly degraded
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 39
areas (where effective functions of the habitat type have been lost) may be substituted for creation
subject to the consultation and concurrence of the Wildlife Agencies. The Coastal Commission shall
be notified and provided an opportunity to comment upon proposed substitutions of substantial
restoration for the required creation component. Development shall be consistent with Policy 7-1 of
the second aadendum to the HMP (i.e., conservation of ESHA), unless proposed impacts are
specifically identified in the HMP; these impacts shall be located to minimize impacts to coastal sage
scrub and maximize protection of the gnatcatcher and its habitat.
-Highlv Constrained Prowrties
There are properties in the Coastal Zone that are entirely or almost entirely constrained by ESHA. In
these cases, one of the following additional standards shall apply: If more than 80 percent of the
property by area is covered with ESHA at least 75 percent of the property shall be conserved, or if the
City, with the concurrences of the Wildlife Agencies and the Coastal Commission through an LCP
amendment, approves a Hardline preserve boundary for any of these properties as part of the HMP,
then the amount of onsite preservation as identified in the Hardline boundary shall apply.
Buffers and Fuel Modification Zones
Buffers shall be provided between all preserved habitat areas and development. Minimum buffer
widths shall be provided as follows:
1. 100 feet for wetlands as defined by California Public Resources Code Section 30121
and Title 14, California Code of Regulations Section 13577(b);
2. 50 feet for riparian areas; however, in some cases the actual buffer area will be higher
due to application of the MHCP and HMP standards; and
3. 20 feet for all other native habitats (coastal sage scrub, southern maritime chaparral,
maritime succulent scrub, southern mixed chaparral, native grassland, oak woodland).
Buffer widths shall be measured from the edge of preserved habitat nearest the development to the
closest point of development. For wetlands and riparian areas possessing an unvegetated bank or steep
slope (greater than 25 percent), the buffer shall be measured from the top of the bank or steep slope
rather than the edge of habitat, unless there is at least 50 feet between the riparian or wetland area and
the toe of the slope. If the toe of the slope is less than 50 feet from the wetland or riparian area, the
buffer shall be measured from the top of the slope.
Any proposed reductions in buffer widths for a specific site shall require sufficient information to
determine that a buffer of lesser width will protect the identified resources. Such information shall
include, but is not limited to, the size and type of the development and/or proposed mitigation (such as
planting of vegetation or the construction of fencing) that will also achieve the purposes of the buffer.
The Department, Service, and the Coastal Commission staff shall be consulted in such buffer
determinations.
No development, grading, or alterations, including clearing of vegetation, shall occur in the buffer
area, except for:
1. Fuel modification Zone 3 to a maximum of 20 feet for upland and non-riparian habitat.
No fuel modification shall take place within 50 feet of riparian areas, wetlands, or oak
wood1 and.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 40
2. Recreation trails and public pathways within the first 15 feet of the buffer closest to the
development, provided that construction of the trail or pathway and its proposed use is
consistent with the preservation goals for the adjacent habitat, and that appropriate
measures are taken for physical separation from sensitive areas. The MHCP and HMP
standards for trails would apply here as well.
'
Buffer areas that do not contain native habitat shall be landscaped using native plants. Signage and
physical barriers such as walls or fences shall be required to minimize edge effects of development.
Grading and Landscaping Requirements
In addition to the requirements of the model grading ordinance in the Carlsbad Master Drainage Plan,
permitted new development shall also comply with the following requirements:
1. Grading activity shall be prohibited during the rainy season: from October 1 to April 1
of each year.
2. All graded areas shall be landscaped prior to October 1 of each year with either
temporary or permanent landscaping materials, to reduce erosion potential. Such
landscaping shall be' maintained and replanted if not well-established by December 1
following the initial planting.
3.
4.
The October 1 grading season deadline may be extended with the approval of the City
Engineer subject to implementation by October 1 of special erosion control measures
designed to prohibit discharge of sediments offsite during and after the grading
operation. Extensions beyond November 15 may be allowed in areas of very low risk
of impact to sensitive coastal resources and may be approved either as part of the
original coastal development permit or as an amendment to an existing coastal
development permit.
If any of the responsible resource agencies prohibit grading operations during the
summer grading period in order to protect endangered or rare species or sensitive
environmental resources, then grading activities may be allowed during the winter by a
coastal development permit or permit amendment, provided that appropriate best
management practices (BMPs) are incorporated to limit potential adverse impacts from
winter grading activities.
Parcel SDecific Standards
Development of the approximately 521-acre City-owned property adjacent to Macario Canyon shall be
subject to the following policies regarding protection of habitat:
1. The impact and conservation areas for the municipal golf course are shown as a
Hardline design in the HMP (Figure B Revised), which shall serve as the standard of
review for determining areas in which development may occur in the future. Areas
shown for conservation shall not be impacted or disturbed except for revegetation,
restoration, and other similar activities related to mitigation. Areas shown for impact
may be fully developed with appropriate mitigation.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 41
2. Any impacts to Coastal Sage Scrub shall be mitigated by on-site creation at a ratio of
2: 1 in compliance with the no-net-loss standard stated above. Onsite revegetation or
restoration may be done on agricultural, disturbed or non-native grassland areas. For
impacts to the gnatcatcher, additional mitigation shall be provided by acquisition and
preservation at a 1: 1 ratio of land supporting gnatcatchers. Impacts to dual criteria
slopes shall not exceed 10 percent.
'
3.
4.
5.
6.
7.
8.
In order to provide a viable north-south wildlife corridor across Macario Canyon, the
area shown on the HMP Hardline map as "Veterans Memorial Park Wildlife Corridor"
shall be conserved concurrent with any impacts to the Macario Canyon property. No
development shall occur within the Wildlife Corridor except a designated trail and rest
areas along the trail.
Protection and management of all mitigation areas shall be consistent with 7-9(f) and
(h) of the second addendum to the HMP (secured with conservation easement, managed
for conservation of biological resources in perpetuity).
The area shown as "Veterans Memorial Park Development Area" is designated for
public recreational use. It is the intent of this policy that the public park area be
developed so as to maximize public access and provide a variety of recreational
opportunities. Steep slope areas shall be planned for more passive type uses with
grading of such areas limited to the amount necessary to allow such uses. Development
within steep slopes and/or native vegetation shall be limited to passive recreational
facilities, such as recreational trails and picnic areas. Within the proposed development
areas, grading of steep slopes with native vegetation shall be limited to the minimum
amount necessary to allow such uses.
Segments of the Citywide Trail System viewpoints, and other opportunities for public
access shall be incorporated into the development areas.
In the riparian area of Macario Canyon Creek, two crossings shall be allowed, as shown
in the HMP Hardline exhibit. Crossing #1 shall utilize the existing farm road. Crossing
#2 shall utilize a bridge span structure. No riparian impacts shall occur for either
crossing.
The design of riparian buffers shall be as shown in the HMP. Buffers shall be
landscaped with appropriate native, non-invasive plants to provide a natural transition
between recreational areas and riparian habitat, as well as to discourage human
intrusion into the riparian area. Appropriate signing and fencing will also be utilized.
The following standards apply to those parcels in Zones 20 and 21 which are located within the
biological core and linkage areas designated in the MHCP. They are in addition to the applicable,
general conservation standards contained in 7-1 through 7-11 and the HMP. In general, each property
shall be allowed to develop at least 25 percent of the site with appropriate mitigation as specified in
7-8 through 7-1 1. When individual properties are proposed for rezoning or development, detailed
biological information will be required to determine whether the proposal is consistent with the HMP,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 42
subsection 7 and the standards below, based upon the actual type, location and condition of onsite
resources, and the appropriate locations of development and preservation areas. One or more wildlife
crossings under Poinsettia Lane of a sufficient size for larger species shall be provided, if
recommended by the wildlife resource agencies.
Additional parcels have specific standards as described below. However, if the City, with the
concurrence of the Wildlife Agencies and the Coastal Commission through an LCP amendment,
subsequently approves a hardline preserve boundary for any of the properties described below, as part
of the HMP, then the onsite preservation included in the Hardline preserve boundary shall apply.
1. Assessor's Parcel No. 212-120-33 (Hieatt) - No impact to vernal pools. Minimize
impact to vernal pool watersheds.
2. Assessor's Parcel No. 212-010-3 (brgis) - Preserve 75 percent of property with
development clustered immediately adjacent to Kelly Ranch.
3. Assessor's Parcel No. 2 15-070-38 (Fernandez) - Cluster development on disturbed areas
to the maximum extent feasible. Maximum 10 percent impact on coastal sage scrub
and southern mixed chaparral for access purposes.
4. Assessor's Parcel No. 215-040-03 (Muroya) - Cluster development on disturbed areas
to the maximum extent feasible. Maximum 10 percent impact on coastal sage scrub
and southern mixed chaparral for access purposes.
5. Aura Circle - development shall be clustered on the south portion of the property.
Grading shall be kept entirely off the largest area of coastal sage scrub in the north part of the site.
Created slopes shall be revegetated with coastal sage scrub, and existing disturbed areas of the project
site that are not identified for development on the hardline map shall be used for onsite mitigation
through restorationhecreation of coastal sage scrub. The post-development habitat area and open
space shall be placed into the HMP preserve.
Preserve Management/Monitoring
The MHCP and the HMP will maintain in perpetuity the biological values of natural resources, where
land is preserved as part of the HMP through acquisition, regulation, mitigation or other means.
Preserved lands that are part of the HMP will require management actions, monitoring, and some land
use restrictions to minimize adverse indirect effects from surrounding development, recreational use,
and fragmentation. The MHCP (Volume 3) provides the framework for which management and
monitoring must occur within each city and throughout the MHCP planning area.
There are three levels of biological monitoring that are the responsibility of the MHCP participating
cities and Wildlife Agencies (depending upon preserve ownership): (1) preserve-level and
Subregional-level monitoring; (2) compliance monitoring; and (3) effectiveness monitoring.
Preserve-level monitoring must be conducted at all of the preserves within the MHCP to assess and
report on key resources within the preserve to inform site-specific management actions by the preserve
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 43
managers. This includes baseline surveys and vegetation mapping at all preserves as outlined in
Appendix B of the MHCP (Volume 3). Some data collected at the preserve level will be aggregated
and analyzed to detect patterns and trends that may not be discerned at individual preserve areas.
Subregional monitoring will sample selected locations across the MHCP planning area to assess
changes in tlie distribution and abundance of covered species.
Compliance monitoring, also known as implementation monitoring, is required to ensure that the cities
are performing the conservation actions required for covered species. Compliance monitoring ensures
the City is meeting all its obligations under the MHCP. One measurement of compliance monitoring
is the City tracking the gains and losses of species and habitat conservation on an annual basis which
is also used for effectiveness monitoring. The MHCP (Volume 3) describes the process for such
accounting.
Effectiveness monitoring will evaluate how well the MHCP conservation and management actions are
achieving the MHCP biological goals for each subarea and across the MHCP planning area. Overall,
the preserve-level monitoring program will be ,used to evaluate the effectiveness of management
actions at the specific preserve areas. At the subregional level, effectiveness monitoring involves
assessing status and trends in populations of covered species and testing hypotheses across the MHCP
planning area.
The City developed a Draft Open Space Management Plan (OSMP) dated May 2004 to describe a
process and structure for open space management and monitoring in the City, to identify and describe
key open space management issues in the City, to recommend strategies and solutions for effectively
handling these open space management issues, and to quantify expected management and monitoring
costs for implementation of the OSMP.
The City has ultimate responsibility for all monitoring, management, and reporting on all OSMP lands
covered by the HMP except those owned andor managed by the Wildlife Agencies as of the date the
Carlsbad HMP IA is signed. More specifically, the City is responsible for overseeing implementation
and maintaining compliance with the HMP by trachng habitat gains/losses using Habitrak; conducting
compliance monitoring; monitoring species and habitat via the preserve steward and preserve
managers; and management and maintenance via the preserve steward and preserve managers. The
City will fund the additional monitoring and management activities needed to close the management
gaps on lands it manages. However, the City will not initially provide active biological management
or monitoring on private lands or existing open space as depicted as Private on figure 2-3 of the
OSMP. The HOA or private landowner will be responsible for controlling trash, fire, and illegal
encampments. However, if funding becomes available, such as through a regional funding source, the
City will coordinate with private landowners and Homeowners Associations to use these funds to
implement and oversee active biological management and monitoring on these lands at the MHCP
level. As a result of this delayed ability to access and fund management and monitoring for such
lands, coverage for certain species (as shown in Tables 2 and 3), are conditioned upon the City gaining
such access and funds.
The City and Wildlife Agencies will meet annually to monitor HMP implementation, discuss pertinent
issues, and coordinate activities relating to overall preserve system monitoring, maintenance and
planning. This meeting will be open to the public. Prior to the meeting, the City will prepare a report
addressing the above terms and submit it to the Service and Department. The report shall be submitted
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 44
not later than December 1 of each year. A diagram is provided in the OSMP which identifies all the
reports and meetings and whm they will occur.
Each preserve manager will develop a preserve management plan that describes the regional
biogeographlc significance and context of the preserve, the baseline biological conditions, and the
known or expected stressors and threats to the biological value of the preserve. The preserve
managers will use consistent survey methods and protocols and a consistent format for the preserve
management plans which are described in the OSMP. The City will need to develop area-specific
management directives (ASMDs) to address monitoring and management issues at the site-specific
level. There is no minimum acreage for which area-specific monitoring and management directives
must be prepared and all subunits of the OSMP that have been included in the HMP/MHCP must have
ASMDs which will be incorporated into the individual preserve management plans. The City will
work with existing preserve managers, future preserve managers, and City open space management
staff to ensure that ASMDs are incorporated from the HhIP/MHCP into the individual preserve
management plans; and the new ASMDs are developed and incorporated as needed. The City will
coordinate submittal of the ASMDs and preserve management plans to the Wildlife Agencies
according to the timetables established in the MHCP. ASMDs and preserve management plans will be
updated every 3 to 5 years as needed. Preserve managers will submit annual reports to the City and
the City will meet with the Wildlife Agencies annually and submit summary reports to the Wildlife
Agencies every three years.
There are two basic phases of implementation of the OSMP. The first phase is intended to establish
the baseline for species status and habitat condition in the preserve areas. Phase 1 occurs within the
first three years after signing the IA or within the first year after a property is hardlined into the
preserve system. The second phase is the ongoing monitoring and management of the preserve system
in perpetuity. Phase 2 starts once the baseline conditions have been established.
The HMP identifies management issues and management recommendations (section F), for which the
OSMP provides additional specific information (section 3), on the commitment of the City toward the
following actions: Area Specific Management Directives, funding sources, fire management policies,
noise impacts to open space, lighting impacts to open space, landscaping and introduction of nonnative
species, invasive ants, outdoor and feral animals, alteration of ecological communities, off-road
vehicles, illegal dumping, management of recreational uses, enforcement, itinerant worker and
transient camps, adaptive management, data management, lagoon management coordination,
restoration, erosion control, public outreach, fencing and signs, and integration of preserve assembly
with Habitrak.
Fire: The City will address basic issues of fire management through a comprehensive update of City
fire management policies and guidelines based on the recommendations of the MHCP monitoring plan
and the WildlandKJrban Interface Task Force or the equivalent current accepted regional fire
management guidelines document. Resource-specific fire management planning will be incorporated
into each individual preserve area plan to coordinate and manage the protection of sensitive resources
during and after a bum event.
Noise: The City will work with preserve managers to develop public outreach and educational
materials regarding the responsibility of “neighbors” adjacent to preserves to minimize their
contribution to edge effects including noise impacts. The City and preserve managers will address
specific noise impact problems with the adjacent residential, commercial, or industrial noise source on
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 45
a case-by-case basis. Possible solutions for attenuation of roadway noise will be investigated by
preserve managers and the City - where high noise levels appear to be substantially reducing the
viability of habitat.
Lighting: The City will work with preserve managers to develop public outreach and education
materials regarding the responsibility of “neighbors” adjacent to preserve areas to minimize their
contribution to edge effects including lighting impacts. The City will continue to require shielding of
major light sources on new development projects, with particular emphasis on light sources near
preserve areas. The City and preserve managers will address specific lighting problems on a case-by-
case basis.
Landscaping/Nonnative species: The City will establish policies and ordmances to increase the use
of best management practices in landscaping (irrigation, fertilizers, pesticidesherbicides) in the
vicinity of the OSMP area, and to reduce the frequency of the selling and planting of species listed as
noxious weeds as identified on the CalEPPC list (Appendix C). The City will work with preserve
managers to identify problem species/areas, to form a coordinated response, and to develop public
outreach and educational materials regarding the responsibility of land uses adjacent to preserve areas
to minimize their contribution to edge effects including landscapinglinvasive plant impacts.
Individual preserve ownedmanagers will work with all property owners adjacent to the preserve to
educate them regarding irrigation runoff and fertilizer use. The City would only become involved in
more serious cases where problems are persistent. Preserve managers will be responsible for
monitoring the potential for spread of invasive species along trails. Where invasive species are
spreading along official trails in the preserve system, these are will be targeted for eradication of
invasive species. The City and preserve managers will address specific problems on a case-by-case
i basis.
Invasive Ants: The City will establish policies and ordinances to increase the use of best management
practices in landscaping with respect to invasive ant species in the vicinity of the OSMP area (e.g., see
landscaping guidelines provided by the MHCP, specifically with respect to minimization of irrigation
runoff). The City and preserve managers will ensure that all landscaping materials used within the
preserve for restoration or landscaping of facilities do not contain Argentine ants, fire ants, and any
other invasive pests.
Outdoor and Feral Animals: The City and preserve managers will develop a focused public outreach
and education program that emphasizes the need for residents to control their pets to minimize their
impact on the preserve system. Feral animals will be removed from preserve areas if possible. The
City needs to work with existing preserve managers to address the issue of effective enforcement and
deterrent methods. The City will increase the frequency of ranger patrols at preserves to increase
public compliance with leash laws.
Alteration of Ecological Communities: The City and preserve managers need to include area-
specific directives in their preserve management plans to periodically monitor the non-native species
that often become abundant in edge-effected habitat. Control and removal programs will be initiated
for any of these species that area shown to be causing the decline in other sensitive species conserved
and managed under the HMP/MHCP. The monitoring and control of these species will be
implemented within an adaptive management context.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 46
Off-Road Vehicles: To better address illegal off-road vehicle use, the City and preserve managers will
work with the ORLE (Off-road Law Enforcement) Team to develop a coordinated response plan. The
coordinated response plan will consist of regular communication between preserve ownedmanagers
and the ORLE Team to identify problem areas and plan enforcement efforts. Since illegal off-road
activity tends to shift from location to location depending on enforcement, the coordination efforts will
identify new “hot spots” with the goal of eliminating all such activities from the preserve system. In
addition, all preserve entrances will include signage prohibiting off-road vehicle activity and providing
a non-emergency phone number for members of the public to directly notify the Carlsbad Police and
ORLE Team when illegal activity is observed. Public outreach and education will be an important
part of the effort to reduce illegal off-road vehicle use.
Illegal Dumping: The City and preserve managers will ensure that potential dumpsites (relatively
remote/hidden sites) in the OSMP area are inaccessible to vehicles through maintenance of gates and
barriers. The City and preserve managers will establish an illegal dumping tipster hotline and post this
phone number along with a non-emergency police number for real-time enforcement response.
Substantial fines will be established, posted on signs and enforced. The City and preserve managers
foster a sense of community stewardship in the OSMP preserve system and “empower” the residents
living near and using the open space to notify the City and law enforcement of any illegal activities
including illegal dumping.
Management of Recreational Uses: The City and preserve managers will incorporate the MHCP
guidelines for recreational uses into each preserve management plan. The MHCP guidelines will be
used to establish a consistent set of rules for the OSMP citywide, to avoid confusion for members of
the public. The City trails team and preserve managers will review the compatibility of the Carlsbad
Citywide Trails Program and update or realign trails as needed in the plan to meet the biological
protection goals and guidelines of the HMP/MHCP.
Enforcement: The City and preserve managers will pool their funding resources to hire five
officerhangers who will assist in preserve enforcement throughout the OSMP area. The City, preserve
managers, and police department will establish a coordinated response plan to address these issues,
and will work together and with local community groups on a public education program to explain
goals and regulations as well as educate the public on the areas’s resources. The City needs to work
with existing preserve managers to address the issue of effective enforcement and deterrent methods.
The City will increase the frequency of ranger patrols at preserves to increase public compliance with
leash laws, trespassing, and other illegal activities.
Itinerant Worker and Transient Camps: The City will continue to work with local and regional
agencies to find long-term solutions for housing of low-income itinerant workers and transients. The
City will also work quickly to implement short-term solutions so that further habitat degredation is
ceased. Note that a continued decline in habitat quality without active intervention from the City
could result in the loss of one or more endangered species permits. The City will coordinate with all
preserve managers to establish a protocol for reporting and handling illegal encampments to protect
the health, safety, and legal rights of everyone involved. Preserve managers and rangers will notify
the police department and the City when illegal encampments are discovered and will work with the
City to remove structures and debris and re-vegetate the disturbed areas as necessary.
Restoration: The City and preserve managers will need to incorporate restoration and enhancement
into the individual preserve management plans. Additionally, detailed restoration management plans
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 47
will need to be prepared for individual restoration projects for restoration required by project-specific
mitigation, for the 104 acresaf coastal sage scrub restoration through the OSMP area, and for
additional restoration needs identified by preserve managers. Restoration management plans will be
consistent with the guidelines provided in the MHCP (Volume 3).
Fencing and Signs: Signage and fencing are the responsibility of the primary management entity for
each preserve area. The City will work with each preserve manager to develop standardized signage
and OSMP rules and regulations to avoid confusion. Signage and fencing will be installed and/or
maintained as described above and in the MHCP (Volume 3).
Erosion Control: The City and preserve managers will need to incorporate erosion control plans into
the individual preserve management plans. The City will assist in coordination and repair of severe
erosion problems. Erosion control and management plans will be consistent with the guidelines
provided in the MHCP (Volume 3).
In addition to preserve level and effectiveness monitoring as described above, the City has an
obligation to conduct compliance monitoring that tracks the gains and losses of species and habitat
conservation and ensures the City is meeting all its obligations under MHCP. The City will use
Habitrak to track and report the gains and losses as they implement their Subarea Plan as described in
Volume 3 of the MHCP.
Plan Implementation
The City will enter into an IA with the Service and the Department for the HMP. The IA defines the
individual and collective roles and responsibilities of the parties in implementing the City's HMP.
The IA is intended to ensure that the HMP will be implemented over the next fifty years and that
Federal and State Take authorizations will be in effect for the same time period, subject to the terms of
the IA.
The HMP and IA describe in detail how the HMP will be implemented. A summary of such processes
is provided below:
The City will implement the plan via the following actions:
1. Immediately upon approval of the HMP, the City will adopt the urgency ordinance
attached to the IA, to require compliance with the plan while permanent regulatory
measures are being drafted and approved.
2.
3.
4.
The City will update the HMP to incorporate the IA with all the exhibits and urgency
ordinance.
The City will update and amend the Open Space and Conservation Element of the
General Plan to incorporate the HMP by reference.
The City's Open Space Ordinance (Section 21 S3.230, Carlsbad Municipal Code) will
be amended to add conserved habitat lands, as identified in the HMP, as undevelopable
open space lands. (See Appendix D of the HMP for recommended amendment
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 48
5.
6.
7
8.
9.
wording.)
The Carlsbad Municipal Code will be amended by the addition of a new section to
require lands located within the standards areas of the HMP to comply with the specific
conservation standards contained in Section D of the HMP. (See Appendix D of the
HMP for recommended wording.)
-
’
The City’s Growth Management Plan contains a requirement that an additional 15
percent of the otherwise developable land within a LFMZ be set aside for open space
purposes. The City will amend this Plan to make the conservation of habitat as
identified in the HMP a priority use for the 15 percent standard in the LFMZs where it
is appropriate (See Appendix D of the HMP for an example).
A formal committee will be created once two or more cities receive an incidental take
permit for their respective subarea plans. This Committee will be comprised of an
Elected Officials Committee and an MHCP Advisory Committee (section 5.7 of the
MHCP, Volume 1).
The City will provide record keeping services that will consist of maintaining current
records of progress made toward meeting citywide conservation goals; actual conserved
habitat within the preserve network, habitat removed by HMP covered projects; and
incidental taking of gnatcatchers and any other Covered Species. The City will
maintain its Geographic Information System (GIS) database of biological resources,
updating it annually and providing the agencies with the updated information. This
information will be provided both in a locational (spatial) format as well as a data
(tabular) format. In addition, an annual meeting will be held among the City, Service,
and Department to monitor HMP implementation, discuss pertinent issues, and
coordinate activities relating to overall preserve system monitoring, maintenance and
planning. Specific details of what will occur at these meetings is provided in the HMP.
The City will institute a proactive educational program to inform current and new
citizens, schools, the business community, and environmental groups about the Plan,
including the importance of future management and ongoing maintenance of the
preserve system. Funding to support this proactive education program would be from
the General Fund or other sources if available.
Funding
The City will expend such funds as may be necessary to fulfill its obligations under the HMP,
including permanent management of the covered habitat areas. The City will notify the Service and
the Department of a material change in its ability to meet those obligations. Funding associated with
implementation of the HMP will be assured through the following as described in more detail in the
HMP and IA:
1. Funding for the conservation, conveyance, and perpetual management of 307.6 acres of land in the
MHCP Core area will be provided from the following sources: the Villages of La Costa project, as
a requirement of the Fieldstone HCP; required offsite mitigation for Carlsbad’s Municipal Golf
Course; previously purchased mitigation for several approved land development projects; and the
adopted Habitat In-Lieu Mitigation fee as described in Section E.6 of the HMP. The methodology
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 49
used in determining the fee is attached to the IA as Exhibit "C." The In-Lieu Fee will be adjusted
upon the effective date of this agreement and will be adjusted in the future, if necessary, based on
the methodology in the Gtachment.
2. The Citywill fund management of the Lake Calavera Mtigation Bank and other City habitat lands
consistent with Section F of the HMP in perpetuity. This cost will be paid for using City funds
through an endowment.
3. The City will fund management of private lands in the preserve by condtioning all private
- development projects to fully fund the perpetual management of preserved habitat land located
within the projects. All projects approved since the HMP was first drafted have been required to
fund endowments for ongoing management, and for all large parcels of habitat, to contract with a
conservation entity to perform ongoing management, maintenance and monitoring in perpetuity.
4. The City's administration of the HMP will be paid for using City funds.
5. Management and monitoring of private lands that do not currently have a land manager,
endowment, and land management plan will be fully funded, managed, and monitored to MHCP
standards once additional funds, such as through a regional funding source, are available.
Provisions for Changed and Unforeseen Circumstances and "No Surprises" Rule
As provided in 50 C.F.R. 17.3, the term "Changed Circumstances, means changes in circumstances
affecting a species or the geographic area covered by the HMP that can reasonably be anticipated by
The City, the Service, and the Department and that can be planned for through the HMP and the
Preserve Management and Monitoring Plan pursuant to Section 12.3 of the IA.
Changed Circumstances to be addressed by the HMP as described in the IA include the following:
1. Fire, occurring in the same location as a previous fire no sooner than three years following nor
longer than ten years subsequent to an initial fire, and damaging up to 5 acres of Preserve habitat.
2. Flood events occurring within the Preserve Floodplains associated with the Encinitas, San Marcos,
Agua Hedionda, Encinas and Buena Vista Creeks and their associated tributaries, at less than 50-
year levels, as determined by the City of Carlsbad Department of Public Works.
3. Climatic drought up to three years in length, as declared by the California State Department of
Water Resources and/or the San Diego County Water Authority.
4. An increase of invasive species within the Preserve to the extent that, as determined by the City in
consultation with the Wildlife Agencies, such increase is of sufficient magnitude to significantly,
adversely affect any Covered Species.
5. Listing of Non-Covered Species.
6. Disease - ie. West Nile virus.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 50
The Changed Circumstances defined by Exhibit B to the IA represent a11 Changed Circumstances to be
addressed by Carlsbad. These Changed Circumstances provisions reflect changes in circumstances
that can reasonably be anticipated to occur to Covered Species or within dedicated Preserve areas.
These Changed Circumstances provisions are not intended to cover the same or similar circumstances
outside Cityjurisdiction nor if they occur within the Carlsbad HMP but outside of the Preserve and
where the City has no legal authority to carry out the Planned Responses, nor if they occur within the
proposed hard-line Conservation Areas depicted on the Revised Figure 6 of the HMP, Addendum 2,
but before the land is lawfully dedicated or conveyed to the Preserve.
Except for the future listing of a non-Covered Species, each of the defined Changed Circumstances
includes an assessment of risk, a description of preventative measures, and a summary of Planned
Responses (measures to be undertaken in the case of Changed Circumstances). Preventative measures
are those measures that are or will be undertaken by the City to reduce the potential for occurrence of
the Changed Circumstances, and/or that reduce the potential for damage to the Preserve resulting from
a Changed Circumstance event. Planned Responses are the specific responses that will be undertaken
in the event of a Changed Circumstance. Planned Responses will not include any actions beyond
those expressly identified in this Exhibit, nor for any event not specifically identified as a Changed
Circumstance. Planned Responses will be implemented to the extent that it is possible to do so and
remain consistent with the primary goal to prevent harm to the public health, safety and welfare.
Planned Responses will be implemented by using the funding sources described in Section 14 of the
L4 for each of the Changed Circumstances, and only to the extent provided by the identified funding
sources.
The City will immediately notify the Service and Department upon learning that any of the Changed
Circumstances listed above and in the required Preserve Management and Monitoring Plan has
occurred, and shall provide written notice within seven (7) days. Within 30 days, the City shall
modify its activities and shall require affected third persons under its direct control to modify their
activities, as appropriate to the extent necessary to minimize and mitigate the effects of the Changed
Circumstances. Changed Circumstances, and planned responses to those circumstances, are described
in Exhibit “B” to this agreement. In addition, the identification of other measures to respond to
Changed Circumstances may be provided for in the Preserve Management and Monitoring Plan
presently being prepared as required by Section 12.3 of this agreement, which will then be
incorporated into the HMP by reference. The City shall report to the Service and Department on its
actions. Such modifications will be initiated without awaiting notice from the Service or Department.
Such modifications are provided for in the HMP and Exhibit “B” to this agreement and do not
constitute Unforeseen Circumstances or require amendment of the Section lO(a)( l)(B) Perrnit, NCCP
Permit, or the HMP.
If the Service or Department determines that Changed Circumstances have occurred and that the City
has not responded, the Service or Department will so notify the City and, as appropriate, direct the
City to make the required changes. Within thirty (30) days after receiving such notice, the City will
make the required changes and report to the Service and Department on its action. Such changes are
provided for in the HMP and Exhibit “B” to this agreement, and do not constitute Unforeseen
Circumstances or require amendment of the Section lO(a)( 1)(B) Permit, NCCP Permit, or the HMP.
The Service or Department may extend the period of time in which to implement the City’s planned
responses upon the City’s showing of good cause, which extension will not be unreasonably withheld.
Pursuant to an order issued on June 10,2004, by the District Court for the District of Columbia in
Spirit ofthe Sage Council v. Norton Civil Action No. 98-1873 (D. D.C.), the Service is enjoined from
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 51
issuing new section lO(a)( 1)(B) permits or related documents containing “No Surprises” assurances, as
defined by the Service’s “No Surprises” rule published at 63 FR 8859 (February 23, 1998), until such
time as the Service adopts new permit revocation rules specifically applicable to section lO(a)(l)(B)
permits in compliance with the public notice and comment requirements of the Administrative
Procedures Act. Until such time as the June 10,2004, order has been rescinded or the Service’s
authority to issue permits with “No Surprises” assurances has been otherwise reinstated, the Service
will not approve any incidental take permits or related documents that contain “No Surprises”
assurances, consistent with the Director’s Order dated June 28,2004.
Critical Habitat
Designated and/or proposed critical habitat for the following species occurs within the MHCP
planning area: federally endangered least Bell’s vireo, Riverside fairy shrimp, San Diego fairy shrimp,
and arroyo toad, and the federally threatened coastal California gnatcatcher.
Least Bell’s vireo critical habitat was designated in 1994 (59 FR 4845). Southwestern willow
flycatcher critical habitat was designated on July 22, 1997 (62 FR 39129). Critical habitat for the San
Diego fairy shrimp was designated on October 23,2000 (65 FR 63438); critical habitat for the coastal
California gnatcatcher was designated on October 24,2000 (65 FR 63680); arroyo toad critical habitat
was designated on February 7,2001 (66 FR 9414); and Riverside fairy shrimp critical habitat was
designated on May 30,2001 (66 FR 29384).
In a court ruling, the final rules designating critical habitat for the San Diego fairy shrimp and coastal
California gnatcatcher were remanded to the Service for further consideration of the economic
impacts. However, the court determined that the previously designated critical habitat for San Diego
fairy shrimp and coastal California gnatcatcher remain in place until such time as revised, final
determinations are made effective.
Pursuant to a separate court ruling, the final critical habitat designations for arroyo toad and Riverside
fairy shrimp were also remanded to the Service for further consideration of the economic analysis;
however, for these two species the court vacated the designated critical habitat.
In a third court ruling, the final rule designating critical habitat for the southwestern willow flycatcher
was remanded to the Service for further consideration of the economic impacts. However, the court
vacated the designated critical habitat for southwestern willow flycatcher.
In compliance with the court ruling for the San Diego fairy shrimp and coastal California gnatcatcher,
the Service published new proposed critical habitat designations. The proposed designation of critical
habitat for the San Diego fairy shrimp was published on April 22,2003 (68 FR 19888), and the
proposed critical habitat designation for coastal California gnatcatcher was published on April 24,
2003 (68 FR 20228). The Service published a proposed critical habitat designation for Riverside fairy
shrimp on April 27,2004 (69 FR 23024) and for the arroyo toad on April 28,2004 (69 FR 23254). In
addition, the Service published a proposed critical habitat designation for southwestern willow
flycatcher on October 12,2004 (69 FR 60706).
The area proposed as critical habitat for the San Diego fairy shrimp within the MHCP and City’s
Subarea Plan is smaller than the amount of land included in the 2000 critical habitat designation;
therefore, we are consulting on those lands currently proposed as critical habitat which are also
included in the 2000 designation
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 52
Within the planning areas for the MHCP and the City’s Subarea plan, some lands designated as critical
habitat for the coastal California gnatcatcher are also included in the April 2003 proposed designation.
In some cases, lands designated as critical habitat are not included in the new proposed designation
and some larids not previously designated as critical habitat are being proposed for designation. The
land proposed as critical habitat for the coastal California gnatcatcher that was not included in the
October 2000 designation lies within the Carlsbad Oaks North project area which was previously
analyzed in a section 7 consultation with the Corps (1-6-01-F-2874 December 4,2003). Some areas
designated as critical habitat in 2000 were not included in the April 2004 proposed critical habitat
designation because the lands were the subject of a section 7 consultation or were in development
prior to the publication of the 2004 proposed rule. For example, the Service consulted with the Corps
pursuant to section 7of the Act on impacts to the coastal California gnatcatcher and its designated
critical habitat within the boundaries of TM-1 and TM-2 of the University Commons project site in the
City of San Marcos (1-6-00-F-2703 July 26,2002 and 1-6-00-F-2285R August 6,2003) and
construction of this project is currently underway. For the coastal California gnatcatcher we are
consulting on all lands included in the 2000 critical habitat designation and those portions which are
also included as proposed critical habitat. We are conferencing on lands currently proposed as critical
habitat, but which were not included in the October 2000 designation.
A portion of the lands proposed as critical habitat for the Riverside fairy shrimp occur within the City
of Carlsbad’s Subarea plan. There is no proposed critical habitat for the arroyo toad within the
Carlsbad Subarea plan, although some areas within the MHCP are included as proposed critical habitat
for the species; therefore, this biological opinion will not address critical habitat for arroyo toad within
the City’s Subarea plan.
Essential habitat for the southwestern willow flycatcher that occurs within the City of Carlsbad was
excluded from proposed critical habitat for the southwestern flycatcher. However, essential habitat
within the MHCP Subregional Plan area is proposed as critical habitat.
It is our opinion that the issuance of an incidental take permit to the City of Carlsbad may affect
designated and proposed critical habitat for coastal California gnatcatcher and San Diego fairy shrimp,
or proposed critical habitat for the Riverside fairy shrimp. We have determined that issuance of an
incidental take permit to the City of Carlsbad will not adversely affect designated critical habitat for
the least Bell’s vireo nor proposed critical habitat for the southwestern willow flycatcher.
We have also determined the MHCP Subregional Plan may adversely affect designated critical habitat
for the least Bell’s vireo, designated and proposed critical habitat for coastal California gnatcatcher
and San Diego fairy shrimp, and proposed critical habitat for Riverside fairy shrimp, arroyo toad, and
southwestern willow flycatcher. We will fully analyze impacts to these species and their respective
proposed and final critical habitat within the MHCP Subregional Plan.
This biological opinion does not rely on the regulatory definition of “destruction or adverse
modification” of critical habitat at 50 CFR 402.02. Instead, we have relied upon the statutory
provisions of the Act to complete the following analysis with respect to critical habitat.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 53
Proposed Permit Special Terms and Conditions
Any future Section lO(a)(l)(B) permit issued to the City under the MHCP plan, will be conditioned by
the Service to include the following special terms and conditions:
-
1.
2.
3.
All sections of Title 50 CFR $5 13, 17.22, and 17.32 are conditions of this Permit. The current
version of these regulations is provided as Attachment 1.
The authorization granted by this permit is subject to compliance with, and implementation of the
Multiple Habitat Conservation Program Plan, Volumes 1, 2, and 3 (MHCP) (dated March 2003);
Habitat Management Plan for Natural Communities in the City of Carlsbad (HMP) (dated
December 1999); the HMP Addendum 1 (dated December 1999) and Addendum 2 (dated June
2003); and the executed Implementing Agreement (LA), all of which are hereby incorporated into
the permit.
The Permittee (City of Carlsbad), its authorized agents, and third parties under the Permittee’s
jurisdiction and control, are authorized to take HMP Covered Species in Attachment 2, subject to
the conditions in Tables 1,2, and 3 of the attachment and as further conditioned herein, to the
extent that take of these species would otherwise be prohibited under section 9 of the Endangered
Species Act of 1973, as amended (FESA), and its implementing regulations, or pursuant to a rule
promulgated under section 4(d) of FESA. Take of HMF Covered Species must be incidental to
otherwise lawful Covered Activities on Covered Lands as defined in the IA and further described
and depicted in the HMP. The amount of take and form of take authorized (e.g. harm, injury, or
death) are described in these tables, and further clarified below.
Table 1:
No take is authorized for the 5 plant species in Table 1. Because take of plants is not
prohibited under FESA, incidental take cannot be authorized under this Permit. Plant
species included in the Permit in Special Terms and Conditions and in Table 1 are
named in recognition of the conservation benefits provided for such plants in the
MHCP, HMP, and IA, and receive those assurances identified in the MHCP, HMP, IA,
and this Permit as provided in Special Term and Condition 14.
Fully Protected Species under California Fish and Game Code may not be taken or
possessed at any time except under limited circumstances, as provided in the Fish and
Game Code. No provision of any other law shall be construed to authorize the issuance
of permits or licenses to take any Fully Protected Species. The following species in
Table 1 are Fully Protected Species: California brown pelican (Pelecanus occidentalis
califomicus); American peregrine falcon (Falco peregrinus anatum); Light-footed
clapper rail (RaZEus Zongirostris Eevipes); and California least tern (Sterna antillarum
brownii).
No take is authorized for the western snowy plover (Charadrius alexandrinus nivosus)
and elegant tern (Sterna elegans).
Take authorization is effective upon Permit issuance for the southwestern willow
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 54
flycatcher (Empidonax traillii extimus), least Bell’s vireo (Vireo bellii pusillus), and
coastal Califmia gnatcatcher (Poloptila califomica califomica).
For each of the remaining 10 animal species in Table 1 which are not listed as
threatened or endangered under FESA, this Permit will become effective with respect to
such species concurrent with their listing under FESA, should they be listed during the
permit term, to the extent that their take is prohibited by FESA: 1) salt marsh skipper
(Panoquina errans); 2) Harbisons’s dun slupper (Euphyes vestris harbisoni); 3) white-
faced ibis (Plegadis chihi), 4) Cooper’s hawk (Accipiter cooperi); 5) osprey (Pandion
haliaetus); 6) yellow-breasted chat (Zcteria virens); 7) California rufous-crowned
sparrow (Aimophila rufzceps cansecens); 8) Belding’ s savavnnah sparrow (Passerculus
sandwichensis beldingi); 9) large-billed savannah sparrow (P. s. rostratus), and 10)
orange-throated whiptail (Cnemidophorus hyperthrus beldingi).
’
Table 2:
Table 2 contains only plant species. No take is authorized for the six plant species
named in Table 2. Recognition of the conservation benefits provided for these species,
and receipt of assurances for them as identified in the MHCP, HMP, LA, and this Permit
as provided in Special Term and Condition 14, is contingent upon: (1) other MHCP
Participating Jurisdictions obtaining coverage for these six species through an existing,
legally operative incidental take permit; and (2) the Permittee demonstrating to the
Service adequate funding for management of conserved areas for San Diego thornmint
(Acanthomintha ilicifolia) and wart-stemmed ceanothus (Ceanothus verrucosus).
Table 3:
Take authorization for the 2 animal species in Table 3 is contingent upon the Permittee
demonstrating to the Service adequate funding and legal access to manage and monitor
these species consistent with the requirements of the MHCP (see Volume 3).
No take of plants in Table 3 is authorized. Recognition of the conservation benefits for
these 11 plant species, and receipt of assurances for them, as identified in the MHCP,
HMP, IA, and this Permit as provided in Special Term and Condition 14, is contingent
upon: (1) the Permittee demonstrating to the Service adequate funding and legal access
to manage and monitor these 11 plant species consistent with the requirements of the
MHCP (see Volume 3); (2) the Permittee receiving legal control over the protection,
management, and monitoring of the vernal pools adjacent to the Poinsettia Train Station
that provide habitat for the San Diego button- celery (Eryngium aristulaturn var.
parishii), little mousetail (Myosurus minimus ssp. apus), spreading navarettia
(Navarettia fossalis), and California Orcutt grass (Orcuttia califomica); and (3) other
MHCP Participating Jurisdictions obtaining coverage for the San Diego marsh elder
(Zva hayesiana) through an existing, legally operative incidental take permit.
Take authorization for the Riverside fairy shrimp (Streptocephalus woottoni), and San
Diego fairy shrimp (B. sandiegoensis) is contingent upon: (1) the Permittee
demonstrating to the Service adequate funding and legal access to manage and monitor
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 55
these 2 animal species consistent with the requirements of the MHCP (see Volume 3);
and (2) the Pqrmittee receiving legal control over the protection, management, and
monitoring of the vernal pools adjacent to the Poinsettia Train Station that provide
habitat for these species.
To initiate coverage for species in Tables 2 and Table 3, the Permittee shall submit in writing a
request for coverage, including documentation of compliance with the necessary conditions of
legally operative permits by other Participating Jurisdictions, funding assurances, andlor legal
access and control. Coverage for these species shall not become effective until such time as both
the Service and California Department of Fish and Game concur in writing that these conditions
have been satisfied.
4. This FESA Section 10(a) Permit also constitutes a Special Purpose Permit under 50 C.F.R. 0
21.27 for the take of those HMP Covered Species which are listed as threatened or endangered
under the FESA and which are also protected by the Migratory Bird Treaty Act of 1918, as
amended (16 U.S.C. 6 §703-712), in the amount andor number specified in the MHCP and
HMP, subject to the following terms and conditions. Such Special Purpose Permit shall be
valid for a period of 3 years from the effective date, provided the Section 10(a) Permit remains
in effect for such period. Such Special Purpose Permit shall be renewed upon written request
to the Service, provided that the Permittee continues to fulfill its obligations under the MHCP,
HMP, LA, and this Permit. Each such renewal shall be valid for the maximum period of time
allowed by 50 C.F.R. 0 21.27 or its successor at the time of renewal.
5. In order to reduce the potential take of eggs or chicks of the coastal California gnatcatcher, the
Permittee shall not allow any clearing and grubbing activities in known and potentially
occupied coastal California gnatcatcher habitat during the breeding season which extends
inclusively from February 15 through August 3 1.
6. In order to minimize impacts to coastal California gnatcatcher, California rufous-crowned
sparrow, and orange-throated whiptail (Cnerniduphurus hyperythrus beldingi) to the maximum
extent practicable, the Permittee shall ensure that if the City of Carlsbad proceeds with plans to
construct Cannon Road Reach 4, the extension of Melrose Drive through the Shelley Property,
or Marron Road through the Sherman Property, the Permittee shall consult with the Service
and California Department of Fish and Game on the preparation of a draft Environmental
Impact Report to ensure that all potential alternatives to construction of these roads are fully
considered. Any alternatives that include the construction of these roads shall meet the
following standards unless otherwise agreed to by the Service and California Department of
Fish and Game due to new information from scientific studies:
a A wildlife movement study that gathers wildlife movement data for at least one full
year shall be conducted preceding the design of any road undercrossings.
animals use it. Sound walls shall be considered along portions of the road that pass
over underpasses in order to reduce noise levels, as increased traffic volume may
decrease the frequency at which a species uses the underpasses.
allow for vegetative cover within the underpass.
a Noise within the underpasses shall be less than 60 dBA during the time of day that
a Shield corridors from artificial lighting. Use skylight openings within the underpass to
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 56
7.
Design underpasses or culverts to be at least 30 feet wide by 15 feet high with a
maximum 2: 1 length to width ratio. A more important variable is the openness of the
underpass, which takes into consideration the height, width, and length of the underpass
(H*W/L). The openness value shall be greater than 0.6.
Underpasses shall be situated along primary travel routes away from areas containing
noise and light pollution and serve only wildlife needs since human presence andor
recreational activities can deter wildlife activity.
installed to complement the underpasses. Fencing shall be used to funnel wildlife away
from at-grade road crossings and toward undercrossings. Fencing shall be at least 8
feet high (measured from the ground up) and placed along portions of the road that
bisect the natural open space to prevent end runs. Coyotes and deer are infamous for
end runs, which means they will continue to shift their movements to go around the end
of a fence instead of using an underpass. Furthermore, the fencing shall also have mesh
that is less than 10 cm x 15 cm and be seated at least 15 cm into the ground to prevent
the animals from exploiting any weaknesses, which would allow them access to the
road. Finally, the fencing shall be installed to “funnel” the animals towards each
underpass by using wing fencing on both sides of the culvert.
surround all underpass entrances and replace any proposed rock fill slope protection.
To maximize the width of the culvert available for wildlife movement, the water
drainage area in the base of each culvert shall be as narrow as possible and placed to the
side, rather than the center. Concrete V-ditches shall be eliminated to allow for natural
stream flows, which provide the elements critical for the movement of sensitive reptile
and amphibian species.
Avoid co-locating human trails with wildlife movement corridorskrossings.
In order to prevent “at-grade” crossing attempts by the target species, fencing shall be
Screen undercrossing openings with natural vegetation. Native vegetation shall
The Permittee shall ensure that the proposed hardline, provided in Addendum 2 to the HMP
(June 2003) in Figure 21, for the Fox-Miller property is not permitted by the City of Carlsbad
under the HMP, because it does not meet MHCP standards. Before it can receive coverage for
thread-leaved brodiaea (Brodiaea fiZifoZia), the City must demonstrate, to the satisfaction of the
wildlife agencies, that this project meets the narrow endemic standards for this critical location
and major population of this species. The Service and California Department of Fish and
Game will consider proposals for this project to meet the conditions of coverage for brodiaea
filifolia. If these agencies concur with a project proposal, and the preserve area is managed
and monitored to MHCP standards in perpetuity, the Permittee would receive coverage for
brodiaea filifolia and the Fox-Miller project could be permitted, under the HMP, through the
amendment process described in section 20 of the IA.
8. In order to minimize impacts to coastal California gnatcatcher, California rufous-crowned
sparrow, and orange-throated whiptail to the maximum extent practicable, the Permittee shall
ensure that any opportunities to maintain and/or widen a corridor of habitat between Carlsbad
and Oceanside are fully considered. This includes the Permittee upholding the City of
Carlsbad’s agreement that should the driving range adjacent to the KellyBartman property be
proposed for a different use, that the City will ensure an on-site corridor is established on the
driving range property.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 57
9.
10.
11.
12.
13.
14.
As part of the review process (e.g., California Environmental Quality Act) for individual
projects within the City of Carlsbad, a qualified biologist shall survey for all species with
immediate and conditional coverage (Attachment 2, Tables 1,2, and 3) in all potential habitat
areas.
The Permittee shall contact the Service’s Carlsbad Fish and Wildlife Office immediately
regarding any violations or potential violations of the FESA or Migratory Bird Treaty Act
(phone 760-43 1-9440).
Within 1 working day of finding dead, injured, or sick endangered or threatened wildlife
species, the Permittee or its designated agents shall orally notify the Service’s Carlsbad Fish
and Wildlife Office (phone 760-431-9440). Written notification to the Carlsbad Fish and
Wildlife Office (6010 Hidden Valley Road, Carlsbad, California 92008) and the Division of
Law Enforcement (185 W. “F’ Street, Suite 440, San Diego, California 92101) shall be made
within 5 calendar days and shall include the date, time, and location of the specimen and any
other pertinent information.
All monitoring and reporting for this permit shall be in compliance with the MHCP (Vol. I and
III) and IA (section 12). Annual reports are due no later than December 1 of each year,
beginning in 2005 and ending in 2054. Copies of all reports shall be submitted to the Field
Supervisor, Carlsbad Fish and Wildlife Office, 6010 Hidden Valley Road, Carlsbad, California
92008, and to the Assistant Regional Director, Ecological Services, U.S. Fish and Wildlife
Service, 91 1 Northeast 11” Avenue, Portland, Oregon 97232.
A copy of this permit must be on file with the Permittee, its authorized agents, and third parties
under the jurisdiction and direct control of the Permittee . Please refer to the permit number in
all correspondence and reports concerning permit activities. Any questions you may have
about this permit should be directed to the Field Supervisor, Carlsbad Fish and Wildlife Office,
at 760-43 1-9440.
On June 10,2004, the court in Spirit of the Sage Council v. Norton, Civil Action No. 98-1873
@. D.C.) ordered that, until the Service completes a rulemalung on revocation standards for
incidental take permits, the Service may not approve new incidental take permits or related
documents containing No Surprises assurances. The order specifically allows for the Service to
issue incidental take permits that do not contain No Surprises assurances. Therefore, the “No
Surprises assurances contained in sections 1.10,2.3,3.26, 10.3.A.(1), 10.3.A.(4), 10.3.C
10.4.2.a, and 18.2.2 of the IA, sections 5.1.1 and 5.2.4 of the MHCP, section G of the HMP
(with Addendum l), and other applicable sections of the IA, MHCP, HMP, and of this Permit,
are currently unenforceable and ineffective with respect to this Permit. The remainder of the
Permit, the IA, the MHCP, and the HMP shall remain in full force and effect to the maximum
extent permitted by law. In addition, in the event that any future judicial decision or
determination holds that the “No Surprises” assurances rule (or similar successive rule) is
vacated, held unenforceable or enjoined for any reason or to any extent, sections 1.10, 2.3,
3.26, 10.3.A.(1), 10.3.A.(4), 10.3.C, 10.4.2.a, and 18.2.2 of the IA, sections 5.1.1 and 5.2.4 of
the MHCP, section G of the HMP (with Addendum l), and other applicable sections of the IA,
MHCP, HMP, and of this Permit, shall be enforceable only to the degree allowed by any such
decision or determination; provided that the remainder of the Permit, the IA, the MHCP, and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 58
the HMP shall remain in full force and effect to the maximum extent permitted by law. In the
event that the No Surprises assurances rule is vacated, held unenforceable or enjoined by a
judicial decision or determination, including the June 10,2004, order described above, but is
later reinstated or otherwise authorized, the assurances provided under the revised rule shall
automatically apply to the MHCP, HMP, IA, and Permit in place of sections 1.10,2.3,3.26,
10.3.A.(1), 10.3.A.(4), 10.3.C, 10.4.2.a, and 18.2.2 of the IA, sections 5.1.1 and 5.2.4 of the
MHCP, section G of the HMP (with Addendum l), and other applicable sections of the IA,
MHCP, HMP, and of this Perrnit. If, in response to any judicial decision or determination, the
“No Surprises” assurances rule is revised, sections 1.10,2.3,3.26, 10.3.A.(1), 10.3.A.(4),
10.3.C, 10.4.2.a, and 18.2.2 of the IA, sections 5.1.1 and 5.2.4 of the MHCP, section G of the
HMP (with Addendum l), and other applicable sections of the IA, MHCP, HMP, and of this
Permit, shall be automatically amended in a manner consistent with the revised rule so as to
afford the maximum protection to the Permittee consistent with the revised rule. Pursuant to
the June 10,2004, order in Spirit ofthe Sage Council v. Norton, Civil Action No. 98-1873 (D.
D.C.), until the Service adopts new revocation rules specifically applicable to incidental take
permits, all incidental take perrnits issued by the Service shall be subject to the general
revocation standard in 50 C.F.R. 5 13.28(a)(5). Additionally, notwithstanding anything to the
contrary in the IA, MHCP, and the HMP, the Service retains statutory authority, under both
sections 7 and 10 of the FESA, to revoke incidental take permits that are found likely to
jeopardize the continued existence of a listed species.
The special terms and conditions provided above will be analyzed in the effects section for each of the
appropriate species.
STATUS OF THE SPECIES AND ENVIRONMENTAL BASELINE’
This Opinion addresses non-listed species in our analysis as if they were listed. Under the provisions
of the “No Surprises” Rule, if one of the non-listed species covered under the incidental take permit
were to become listed, our analysis in this Biological Opinion allows for the City to remain secure
regarding the agreed upon cost of conservation and mitigation, per the HMP and associated
documents. However, as stated previously in this Opinions, pursuant to an order issued on June 10,
2004, by the District Court for the District of Columbia in Spirit ofthe Sage Council v. Norton Civil
Action No. 98-1873 (D.D.C.), the Service is enjoined from issuing new section lO(a)(l)(B) permits
containing “No Surprises” assurances.
All Species
In general, organisms depend on certain necessary elements within the environment for survival. This
suite of elements (some of which are more important than others) comprise the organisms’
habitat. Typically, organisms that comprise a species have similar habitats. For most species, the
actual suite of specific elements needed for them to survive is not known. However, the vegetation
’ Because of the large number of species included in this Opinion, we have modified the organization from
the recommended format in our “Endangered Species Consultation Handbook”. Each component of the formal
consultation is discussed in general terms first (and includes the recommended standard paragraphs), and is then
included for each species, as appropriate, in a species-by-species evaluation section.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 59
communities in which the species occurs can generally serve as a useful proxy for describing a
species’ habitat. Some species’ habitats can be better described by certain specific physical
environments (e.g., wetland types). The MHCP Subregional Plan includes a discussion of the major
vegetation communities (habitats) within the Subregion and describes the covered species in relation
to these majbr vegetation communities. Due to the dual programmatic- and project-level aspects of
the permit application, this Biological Opinion will address species included in all Tables 1,2,3, and
4. Species in Tables 1,2, and 3 will be analyzed from both a subregional context and City specific
context. Species in Table 4 will be analyzed mainly from a subregional context, however they will
also be analyzed to assure that permitting the City HMP would not jeopardize the continued existence
or recovery of these species. Volume 2 of the MHCP provides great detail on the conservation goals,
conservation strategy, coverage determination and permit conditions, background, conservation
analysis, and adaptive management for each plant and animal species and is hereby incorporated by
reference.
Environmental Baseline, General
Regulations implementing the Act (50 CFR 5402.02) define the environmental baseline as the past and
present impacts of all Federal, State, or private actions and other human activities in the action area.
The environmental baseline must also consider the anticipated impacts of all proposed Federal projects
in the action area that have already undergone section 7 consultation. The HMP recognizes those
projects that were exempted from take via consultation under section 7 with a federal agency. The
acreage totals provided in Table 13 of this Opinion (Table 8 of the HMP) were updated to account for
all of the projects that have been approved either by the City or by the Service via formal consultation
with the U.S. Army Corps of Engineers under section 7 of the Act or consultation under 4(d) of the
Act, except for the Carlsbad Oaks North project. The Carlsbad Oaks North project was a recent
formal consultation with the U.S. Army Corps of Engineers under Section 7 of the Act. Because this
is the most recent project approved under section 7 of the Act and the City did not have all the
information necessary at the time Table 13 was updated, the Carlsbad Oaks North project was omitted.
Our non-jeopardy non-adverse modification biological opinion for the gnatcatcher and its critical
habitat was issued in December 2003 under project number 1-6-01-F-2874. The project site also
included San Diego thorn-mint (Acanthomintha ilicifolia) and thread-leaved brodiaea (Brodiaea
filifolia), however, no impacts to these species would occur from the proposed project, so they were
not addressed in consultation 1-6-01 -F-2874. Since the following projects have been approved in the
past and we have completed formal consultation on the Carlsbad Oaks North project, these projects
and their effects are treated as the environmental baseline and any take associated with these projects
are not analyzed in this opinion: Manzanita Partners, Palomar Forum, Bressi Ranch, Calavera Hills,
Kellymartman, and Raceway. All of the above listed projects, except Kelly/Bartman were approved
consistent with the proposed hardlines in the HMP. The KellyBartman project is described in more
detail in the project description and the appropriate species evaluation sections.
i
The Subarea contains a large number of fragmented habitats, of which some are supported with
wildlife undercrossings, while others present road mortality concerns. Important wildlife corridor-
road intersections that provide wildlife undercrossings are located at: College Avenue (within the
Robertson Ranch Panhandle), Cannon Road and El Camino Real, Faraday Avenue (within the Tchang
property), Melrose Avenue (within Raceway property), El Camino Real (east end of Raceway
property), El Fuerte and Poinsettia Avenue, Rancho Santa Fe Road (within Village of La Costa), and
Cannon Road bridge (east of Interstate 5). Currently Palomar Airport Road lacks a sufficient wildlife
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 60
crossing allowing wildlife to move between native habitats on either side of the road. However, some
funding is available from the-Raceway and Palomar Forum projects to construct an undercrossing for
Palomar Airport Road on the Raceway and Rancho Carillo properties.
EFFECTS OF THE ACTION
General Direct Effects
MHCP Subregional Scale
The Subregional MHCP Plan only acts as an umbrella framework plan. Each City within MHCP will
be applying for an individual permit under section lO(a)( 1)(B) of the Act. Accordingly, direct impacts
to covered species and their habitats are anticipated to only occur within individual cities as they
obtain an individual permit under section lO(a)(l)(B) of the Act. However, here it is appropriate to
acknowledge the impacts to Covered Species and Non-Covered Species for the Carlsbad HMP within
the context of implementing the MHCP. We are assuming that the MHCP is implemented as
described in Volumes 1,2, and 3 by all the participating cities. This is not an unreasonable
assumption since all of the participating cities agreed to the text in Volumes 1, 2, and 3 and
unanimously voted to finalize the MHCP Volumes ,I ,2 , and 3 and the EIS associated with
implementing the proposed alternative of the MHCP. In order to change any of the policies of the
MHCP documents, all the cities would need to reconvene and vote to make such changes. In
addition, additional CEQA and NEPA would likely be necessary.
The estimated acreage of conservation (and impacts) within the MHCP planning area are provided in
Table 12 below (MHCP Volume 1 Table 3-3). As shown in Table 12, the preserve within the MHCP
cities will be approximately 19,928 acres which represents 67 percent of the total acres of undeveloped
habitat (native and non-native) available within the MHCP cities. In addition, approximately 500
acres of additional coastal sage scrub will be preserved in the gnatcatcher core area in unincorporated
San Diego County.
The MHCP subregional plan provides a framework, policies, and guidelines which each City will be
responsible for meeting in their subarea plan. Draft subarea plans have been created for the following
Cities in addition to the City of Carlsbad: Encinitas, Escondido, San Marcos, and Oceanside. The
Wildlife Agencies continue to work closely with these Cities and the City of Vista to develop a
subarea plan that meets the goals and requirements of the MHCP framework plan. Although some
Cities are close to requesting an incidental take permit for their subarea plan, all plans are in draft form
and are not analyzed in this Opinion. Our evaluation of each City's FPA design will occur for each
city separately when they request an individual permit under section 10(a)l(B) of the Act. It is our
expectation that the ITA preserve areas and conservation levels for certain parcels in the FPA will
need to be modified to meet the conditions of coverage for certain species as described in Volume 2 of
the MHCP. Assuming full implementation of the MHCP, the FPA is used as a guide to provide the
minimum amount of preservation for each species and their habitats at the MHCP subregional scale.
In addition, because the conservation of lands within the gnatcatcher core area are represented by a
range between 400 acres and 500 acres, we have assumed the minimum preservation of 400 acres in
our analysis of effects.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 61
Table 12 Conservation Acreages of Natural Vegetation Communities in the MHCP
Planning Area
~~
Total T&OJ&Ckn&n
Total Existing Conservation Conserved in inside the
Vegetation Community in Study Area inside FPA Study Area BCLA'
Southern coastal bluff scrub 2 0 0 (0%) 0 (0%)
Maritime succulent scrub 32 29 29 (90%) 29 (93%)
Coastal sage scrub 8,656 5,334 5,334 (62%) 4,948 (69%)
Chaparral 8,324 5,806 5,806 (70%) 5,615 (73%)
Southern maritime chaparral 968 748 748 (77%) 717 (79%)
Coastal sagekhaparral mix
Grassland
Southem coastal salt marsh
Alkali marsh
Freshwater marsh
Riparian forest
Riparian woodland
Riparian scrub
Engelmann oak woodland
Coast live oak woodland
Other oak woodlands
Freshwater
Estuarine
Disturbed wetland
462
5,219
272
165
518
676
250
1,739
230
650
1
444
955
202
246
1,687
25 1
157
428
533
180
1,283
188
511
1
40 1
947
12 1
246 (53%)
1,687 (32%)
272 (100%)
165 (100%)
518 (100%)
676 (100%)
250 (100%)
1,739 (100%)
188 (82%)
5 11 (79%)
1 (100%)
444 (100%)
955 (100%)
202 (100%)
237 (54%)
1,565 (47%)
270 (100%)
165 (100%)
442 (100%)
404 (100%)
133 (100%)
1,191 (100%)
185 (89%)
483 (83%)
l(lOO%)
396 (100%)
954 (100%)
87 (100%)
Natural floodchanneYstreambed 142 142 142 (100%) 130 (100%)
Beach 48 7 8 (16%) 8 (33%)
SaltpadMudflats 8 7 8 (100%) 8 (100%)
Vernal poolz 22 9 22 (100%) 17 (100%)
~
Total 29,962 19,007 19,928 (67 %) 17,966 (73 %)
Note: Numbers may not sum to total as shown due to rounding and because vernal pool acreage is
excluded.
Source: Vegetation acreage calculations from October 2002 SANDAG GIS calculations.
'Acreage and percentage of each vegetation community inside the biological core and linkage area that will
be conserved.
'Vernal pools were mapped as an overlay to other vegetation communities and thus their acreage is not
included in this total. The MHCP study area does not include the San Marcos Major Amendment Area.
.-
Projected Total Total Existing
Acres Estimated Conserved Habitat Acres
Conserved in Acres as % of Citywide
Standards Conserved Existing Adjusted for
Areas VLC (2)
550 5,733 65% 6,997
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Total
Estimated Adjusted %
Acres. Cons Conserved (4)
Adj for
VLC(3)
4,983 71%
62
Existing
Habitat
Acres
Citywide (1)
Estimated Total Acres 8,758
Coastal Sage
Scrub 3,3 15
Chaparral ~ 968
Southern
Maritime 392
Tabla
Acres Acres
Conserved Conserved in
in Existing Proposed
Hardline Hardline
Areas Areas
3,940 1,243
1,281 585
493 .I 70
255 33
3,025
1,176 ' 292
50
5
80
114
1,149
159
Chaparral I I I
Oak 29 I 41 12
35%
35%
30%
13%
17%
0%
0%
62%
62%
Woodland
1,366 1,141
Grassland 1,856 40 1 252
Eucalyptus
Woodland 258 96
273
13
2,139 65% 2,288 1,581 69%
676 70% 79 1 639 81%
54
8
342 87% 296 266 90%
24 83% 23 22 96%
110 I 494 I 100% I 513 I 449 I 100%
38
54
~~ 1,252 100% 1,370 1,273 100%
707 38% 1,464 654 45 %
0 99 38%
Additional
Conservation
on Dist. Lands
Total Cons.
wlin Carlsbad
Conserved
Parcels within
MHCP Core
Total
Conservation
wlin Carlsbad
plus MHCP
Core Area
Parcels
252 99 39%
Carlsbad Subarea Plan Biological and Conference Opinions (F’WS-SDG-847.4) 63
Carlsbad Subarea Scale -
Impacts to covered species and their habitat within the City will result from private development
projects and public projects that are consistent with the Subarea plan. In addition, where preserve
areas are planned adjacent to existing developed areas, the fuel management zone may encroach into
the preserve, however, such impacts would not occur greater than 100 feet from habitable structures.
If such activities would impact a major population or critical location, the City would need
concurrence from the Wildlife Agencies for any such impacts. Under the City’s plan 5,733 acres of
habitat will be conserved within the City out of an existing 8,758 acres of habitat remaining in the
City. An additional 308 acres of conservation (predominantly coastal sage scrub) will occur outside of
the City in the MHCP gnatcatcher core area as part of the City’s obligation under their HMP. 745
acres of disturbed lands will also be conserved within the City. These numbers are provided below in
Table 13 and in Addendum 2 of the HMP as Table 8.
Direct effects from the proposed plan may include injury, death andor harassment of listed, sensitive,
and narrow endemic species. Direct effects may also include the destruction of habitats necessary for
species breeding, feeding, or sheltering.
Appendix C of the Subarea plan and MHCP Volume 2 summarizes the level of loss anticipated for
each Covered Species, either as the percent of the known populations or as the percent of appropriate
habitat if designation of populations was not possible due to the lack of available data. Precise
quantification of effects to species numbers was not possible because of natural population
fluctuations and because less than half of the habitat lands in the Subarea have been surveyed for the
presence of proposed covered species. Surveys that have been conducted are generally attempting to
determine presence/absence and have not been designed to arrive at a population estimate (i.e., they
fail to meet assumptions of randomness, independence, and usually have failed to account for
detection probabilities). Therefore, estimates of observation points lost in Appendix C of the HMP or
Volume 2 of the MHCP may not be strongly correlated to actual numbers of individuals lost. New
projects will still be required by the jurisdictions to conduct biological assessments to ensure that
projects minimize and mitigate effects to covered species and will undergo project specific CEQA
review. The amount of habitat developed and conserved will be reported through an annual review
process as required by the HMP.
The preserve system will be actively managed for covered species and their habitats. Initially 5,421.8
acres of the preserve will be actively managed. Once regional funding is available and access issues
are resolved, the entire preserve area within the City will be managed and monitored per the standards
in the OSMD and MHCP Volume 3. Regional funding will be on the November 2004 election,
however, if it doesn’t pass this year, it will be another two years before it can even go to vote again.
Direct effects to each species from development will also be minimized through implementation of the
conservation measures for covered species as presented in Table 9 of the Subarea plan and Volume 2
of MHCP. Furthermore, there is a no net-loss policy for wetlands where any direct effects to
wetlands, including vernal pools in naturally occurring complexes, will be avoided to the maximum
extent practicable both inside and outside the preserve, and mitigated according to the standards
described in the project description.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 64
General Indirect Effects -
MHCP Subregional Scale
Indlrect effects from the proposed plan may include habitat fragmentation, edge effects, noise effects,
disruption of the natural fire regime, changes in hydrology from adjacent development, increased
lightning, and the proliferation of exotic species.
Standard best management practices contained in Appendix B of MHCP Volume 2 include measures
that must be implemented to ensure coverage of species and to avoid and minimize the following
effects:
Habitat Fragmentation. Fragmentation of habitat can have negative effects on the population
dynamics of many species (Rosenberg et. al. 1997). Habitat fragments generally have less
conservation value than large habitat blocks because smaller habitat areas usually contain fewer
species, have proportionally larger perimeters (making them more vulnerable to edge effects), are
more likely to be biologically isolated from other habitat areas, and tend to be more vulnerable to
adverse stochastic events. Smaller reserves are faced with an increased likelihood of extinction of
some species because of reduced population sizes and diminished dispersal ability (Primm et al. 1988).
Natural landscapes are generally more connected than urban landscapes, and linkages (or corridors)
are one strategy to retain or enhance some of that natural connectivity (Noss 1987). Linkages are
habitat connections between larger preserve areas which allow for wildlife movement, recruitment,
and colonization between different core biological areas. Protecting naturally existing linkages likely
promotes ecological processes and may benefit regional and local biological diversity (Rosenberg et
al. 1997). However, the creation of linear patches intended to function as linkages may not fully
mitigate for further habitat removal and it is important to evaluate both the effectiveness of biological
corridors and the tradeoffs with diminished habitat areas that accompany many HCPs (Rosenberg et al.
1997).
Linkages can be important for allowing some species to move from their natal areas to sites where
they reproduce. Linkage habitat can facilitate movement between core population areas in some
species, preventing genetic isolation, and may allow for immigration into areas where populations had
been locally extirpated. When large blocks of habitat remain intact, the rate of successful dispersal
between core populations is higher for some species (Beier and Noss 1999). When the distance
between core populations of a species is greater than the dispersal distance for individuals, linkages
must provide live-in habitat to remain effective.
Some species require corridors to move between habitat patches within the Subarea. The narrowing of
existing corridors of native habitat, increased fragmentation of stepping stone habitat patches, along
with increased human density and auto traffic, may significantly impede the movements of several
taxa. Fragmentation generally adversely affects birds, reptiles, amphibians, mammals, and
invertebrates. It can also adversely affect plants due to the need for seed dispersal and pollinator
dispersal.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 65
Studying coyote use of urbaa habitats, Gibeau (1993) observed 21 study animals killed on highways
between July 1991 and March 1993. This constituted a 35 percent highway mortality rate. Coyote
and bobcat prey includes smaller animals that prey upon suitable bird species and their nests. Absence
of coyotes ahd bobcats may thus result in greater numbers of small predators, leading to the local
extirpation of some bird species (Crooks and Soul6 1999). Connectivity between and within proposed
and existing preserve units must be provided through wildlife crossings for mammals and reptiles.
Traffic speed is thought to be correlated with risk of mortality of animals crossing roads (Jones 2000).
The wildlife undercrossings throughout most of the Subarea are expected to allow mobile non-flying
species to move within or through the preserved habitat with a lower risk of traffic-related mortality.
However, undercrossings are not expected to reduce the risk of direct traffic-related mortality to some
animal species.
Edge Effects. Another negative effect of fragmentation is exposure to incompatible land uses along
the habitat edge (edge effects). The biological integrity of habitats adjoining development can be
diminished by adverse effects of noise, lighting, exotic plant and animal invasion, dust/air pollution,
predators, parasites, disturbance from human activities, pesticides, fuel modification, and other factors.
Numerous predators such as snakes, opossums, raccoons, skunks, ground squirrels, and various
corvids thrive on edges by making use of the additional food and water sources provided by residential
and golf course development adjacent to preserves. Brood parasitism by edge effects and creation of
cowbird foraging habitat associated with development of golf courses and equestrian centers as radio-
tagged cowbirds show that they can move 7 kilometers between breeding and feeding areas (Rothstein
et al. 1984).
Predation by domestic cats has caused, or significantly contributed to, the extinction of many animal
species (including mammals, reptiles, and birds) around the world and they remain a continued threat
to many threatened and endangered species (Nogales et al. 2004). The damaging effects of cats on
wildlife are particularly severe on oceanic islands and in islands of habitat in urbanized areas (Jurek
1994). We expect the proposed action to result in a larger cat population (in terms of spatial
distribution and number of individuals), due to an increase in the number of houses and people, and a
decrease in the number of dominant predators (namely coyotes) within urban habitat fragments
(Crooks and Soule 1999). As cat populations increase and expand it is likely that smaller habitat
fragments will experience local extirpations, due in part to the increased predation by domestic cats
(Crooks et al. 2001). Crooks and Soule (1999) found that 32 percent of residents bordering San Diego
habitat fragments owned cats, and on average each cat owner owned 1.7 cats. Seventy-seven percent
of cat owners let their cat outdoors and 84 percent of outdoor cats brought back kills (mostly native
species) to the residence. Cat owners reported that each outdoor cat that hunted returned on average
24 rodents, 15 birds, and 17 lizards to the residence each year. Based on these numbers they estimated
(conservatively, because these numbers are based on kills returned to the residence) that cats in a
moderately sized habitat patch surrounded by appropriately 100 residences killed 840 rodents, 525
birds, and 595 lizards per year.
i
We expect the proposed action to result in the construction of more houses which will result in
increased human population and more people seeking recreational opportunities within the plan area.
Increased human use of recreational trails in and around wildlife preserves is likely to disrupt breeding
activities and increase the potential for predation by altering spatial or temporal behavior patterns
through alarm or avoidance responses. Miller et al. (1998) found that nest predation was significantly
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 66
greater near recreational trails than away from them, and that birds were less likely to nest near trails,
in Colorado grasslands. Miller et al. (2001) found that western meadowlarks (Sturnella neglectu) and
vesper sparrows (Poocetes grurnineus) flushed in response to pedestrians, dogs, and pedestrians with
dogs, on- or bff-trails. Flushing probability was greater when dogs were off leashes because this
created two sources of disturbance (human and dog) rather than one (human with dog on leash). Trail
networks in the Calavera Preserve have been, and are currently, heavily used by motorcycles, bicycles,
and off-highway-vehicles having detrimental results to the habitat and associated species. Attempts to
control illegal usage of the Calavera Preserve has proven to be very difficult (McKee pers. corn
2003).
Alteration of Fire Regimes. Alteration of the natural fire regime could lead to an elimination of fire
in small habitat fragments adjacent to development or to an increase in fire frequency from
anthropogenic ignition. Where new development is planned, brush management will be incorporated
within the development boundaries and will not encroach into the preserve.
Noise. Development adjacent to preserves is likely to result in higher ambient noise levels within
portions of the preserve which is likely to adversely affect some Covered Species within the preserve.
The impact of noise on wildlife is likely to differ from species to species and is not only dependent on
the source of the noise (e.g., aircraft vs. blasting), but also on the duration and schedule. Organisms
that rely on sound to communicate (e-g., birds, frogs, etc.) may be indirectly impacted from noise.
Construction activity, for example, that is outside of the Preserve may generate noise that impacts
species within the preserve. Similarly, nighttime lighting from outside the Preserve may also
illuminate areas within the preserve, which could disrupt animal behavior. For example, noise may
alter time-consuming and energetically expensive behaviors (Le., calling, singing, attack) of birds.
Therefore, increased noise levels have the potential to lower reproductive fitness by affecting
territorial defense, mate acquisition, the ability to detect conspecific encroachments, foraging
(Atkinson 1997), and predator avoidance (Scherzinger 1979).
Changes in Hydrology. Changes in the character of urbanization outside the preserve system may be
indirectly affected by implementation of the Subarea Plan. Resulting changes in hydrology, run-off,
and sedimentation could indirectly impact surface water dependent Covered Species within the
preserve system. Increased urban run-off into the preserve system and channelization for flood control
is likely to result in increased erosion and increased rates of scouring, which is likely to result in
downstream habitat loss for some species. Urbanization increases the magnitude and frequency of
high flows causing bank erosion and channel widening (Poff et al. 1997). Such geomorphic changes
are likely to adversely affect species which depend on natural flow regimes for their persistence.
Urban run-off generally contributes higher sediment loads to adjacent streams due to the presence of
construction sites, denuded surfaces, and eroded streambanks (EPA 2003). Urban run-off increases
the temperature of adjacent streams due to higher water temperatures from streets, roof tops, and
parking lots, and increases the variety and amount of pollutants carried into streams, rivers, lakes, and
lagoons; pollutants include: 1) sediment, 2) oil, grease, and toxic chemicals from motor vehicles, 3)
pesticides and nutrients from lawns and gardens, 4) viruses, bacteria, and nutrients from pet waste and
failing septic systems, 5) heavy metals from roof shingles, motor vehicles, and other sources (EPA
2003).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 67
Changes in hydrology as a result of lagoon maintenance, enhancement projects, or essential public
works projects could have indirect impacts to those species which use Pacific Ocean, coastal lagoon,
and/or freshwater/brackish water marsh habitat at some point in their life history. Dredged sediment
being removed from the lagoons can contain contaminants that could be re-suspended and made
available for uptake by plant and animals species through bioaccumulation. Biomagnification may
concentrate these contaminants as they move up through the food chain. The resuspension could also
impede sight feeding behaviors by some species.
Lighting. Artificial night-time lighting adversely impacts the habitat value of the preserve system,
particularly for nocturnal species through potential modification of predation rates, obscuring of lunar
cycles, andor causing direct habitat avoidance. Illumination of foraging habitat by artificial light
during surface activity periods of prey likely makes detection by predators easier, potentially
increasing the predation rate by owls, coyotes, fox, house cats, etc. Artificially lit habitat areas may
also be directly avoided by certain species.
Illumination of bird habitat by increased night lighting of the Subarea has the potential to adversely
affect bird species. Physiological, developmental, and behavioral effects of light intensity,
wavelength, and photoperiod on domestic bird species are well-documented. In the wild, urban
lighting is associated with early daily initiation of song activity in great tits (Parus major) and
chaffinches (Fringilla coelebs) (Bergen and Abs 1997). Black-tailed godwits (Lirnosa lirnosa) placed
their nests significantly farther from motorway lights than from unlighted controls (de Molenar et al,
2000). Placement of nests away from lighted areas implies that part of the home range is rendered less
suitable for nesting by artificial light. If potential nest sites are limited within the bird’s home range,
reduction in available sites associated with artificial night lighting may cause the bird to use a
suboptimal nest site, that is more vulnerable to predation, cowbird parasitism, or extremes of weather.
It is reasonable to assume that variations on the natural lighting regime may have similar effects on
other bird species.
Exotic Species. Native species are often at a disadvantage after exotic species or nonnative predators
are introduced. Nonnative plant and animal species have few natural predators or other ecological
controls on their population sizes, and they often thrive in disturbed habitats. These species may
aggressively out-compete native species or otherwise harm sensitive species. When top predators are
absent, intermediate predators multiply and increase predation on native bird species and their nests.
Feral and domestic holding areas, and golf courses provide resources for increased populations of
parasitic cowbirds, which adversely effect native songbird populations. Litter and food waste from
migrant worker camps and picnickers can contribute to an increase in Argentine ant populations which
out-compete native ants. Invasive plant species such as salt cedar (Tarnarix sp.) and giant reed
(Amndo donax) can alter water flow and quantities resulting in adverse effects to water dependent
species.
Argentine ants may affect terrestrial invertebrates through direct predation and competition. For
example, Argentine ants have the potential to impact Quino checkerspot butterfly eggs and larva, they
also may affect the food sources for orange-throated whiptail lizards (termites) and San Diego homed
lizards (native ants). Reptiles could also be directly depredated by Argentine ants. Bird nestlings are
also susceptible to depredation by Argentine ants.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 68
Management and Monitoring
To help minimize aDd mitigate direct and indirect impacts, the City’s Subarea Plan includes a draft
City of Carlsbad Open Space Management Plan as described in the project description of this
Biological Opinion.
The City’s program for monitoring and management of the Preserve will provide many minimization
measures to further reduce impacts to covered species. In total, the program will provide important
measures to help assure that ecosystem function is maintained within the Preserve and the populations
of covered species contained therein continue to be viable for the life of the permit.
In all, because the monitoring and management provisions will be used to guide long-term
management at the site-specific level it is critical for minimizing and mitigating direct, and especially,
indirect effects that could occur as a result of this action.
Species Evaluations
Evaluation Assumptions
Because this action includes potential direct and indirect impacts over a large area and is addressing a
large number of species, we do not necessarily have information from focused surveys for covered
species for the entire action area. Additionally, the impacts associated with this action could occur
anytime over the 50-year term of the permit. Therefore, we made certain assumptions to evaluate the
impacts to individual species below. These include:
1.
2.
3.
We assume that certain vegetation communities (e.g., coastal sage scrub) or physical
environment features (e.g., wetlands) are synonymous with the habitat of certain species
(species-specific habitat information is provided in the species accounts). Additionally, for the
purposes of determining impacts to (and conservation of) covered species, we assume that a
given quantity of impacts to the vegetation community or environmental feature (Le., habitat)
will result in a similar quantity of impacts to the species numbers, distribution, and
reproduction as a whole. We expect that if one were to use a strict interpretation of the above
assumptions, it would provide a “worse-case scenario” for evaluating impacts to habitat. We
recognize, however, a strict interpretation is not necessarily realistic. However, given the
information available to us, we believe that these assumptions are appropriate for our
evaluation (see below).
We assume that the estimated acreages of impact presented in Tables 12 and 13 of this
Biological Opinion will not be exceeded and thus are maximum values. As such, the
complementary conservation values presented in Tables 12 and 13 are assumed to be minimum
values. These values represent the conservation provided by the MHCP’s subregional and
City’s preserve design.
We assume, in accordance with the requirements of the Plan, that prior to project impacts,
site-specific evaluations will be conducted by a qualified biologist to determine whether
additional general or focused biological or wetland surveys will need to be conducted. We
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 69
further assume that if during the aforementioned evaluations the biologist determines that
additional surveys are needed, the surveys will be conducted by a qualified biologist at the
apprqpriate time of the year (which may vary, depending on the subject of the survey) to the
extent necessary (in area and effort) such that if the subject of the survey is not detected, then it
is reasonable to conclude that the subject does not occur within the surveyed area. This is
especially important for: 1) Narrow Endemic Species-within all areas of the Subregional
planning area and the City’s Subarea except within Hardline Conserved Areas; 2) Wetlands
(including vernal pools)-within all areas of the Subarea; 3) certain covered species with
special survey provisions (e.g., least Bell’s vireo, southwestern willow flycatcher,
etc.)-within certain areas as specified by the MHCP Subregional Plan Volumes 2 and 3; and
4) all covered species-within the Preserve. Additionally, we assume that if Nmow Endemic
Species or Wetlands are detected within the survey area, the survey(s) will adequately quantify
(numerically and/or spatially, as appropriate) so that the avoidance, minimization, and
mitigation measures proposed in the Subregional Plan and City’s Subarea Plan can be
implemented to the appropriate extent.
4. We assume that all of the provisions within all three volumes of the MHCP Subregional Plan
and the City’s HMP will be fully implemented. These, in general, include (but are not limited
to) the provisions for avoidance, minimization, and mitigation (including, but not limited to,
the Narrow Endemic policy, the Wetlands Protection Program, and Standards for Estuarine
Species), and the species-specific requirements of MHCP Volume 2 for covered species once
the City receives coverage for those species; and the provisions for monitoring, maintenance,
and management of the Preserve. We further assume that long-term provisions (e.g.,
monitoring, management that adaptively responds to observations made during monitoring,
etc.) continue to be fully implemented in perpetuity. However, we did account for the
difference in those lands that will be managed and monitored initially than those that would not
be managed and monitored until additional funds, such as a regional funding source, are
available. In total, these provisions provide the avoidance, minimization, and other mitigation
measures that assure the goals of the MHCP Subregional Plan and City’s Subarea Plan will be
met, and therefore are critical to our analysis of effects.
Plants, General
It is anticipated that there will be direct and indirect effects impacting plants as a result of the proposed
action. Generally, these will be the same as the direct and indirect effects described above.
Plants are susceptible to a number of indirect effects. Some plants are more dependent upon a
functioning ecosystem in order to survive. For example, certain plants require outside agents to be
pollinated. If the pollinators are impacted, then those plants will also be impacted. Additionally,
Argentine ants may remove seeds from the seedbank, promote parasitic insects, and impact
pollinators, among others. Wetland species may be affected by changes in hydrology, water quality,
timing, etc.
Although the proposed action will result in habitat loss, and loss of individual plants, the size and
configuration of the HMP and MHCP will allow for the conservation of covered plant species within
these areas. Not only will individual plants and their seedbanks be managed and monitored within the
Carlsbad Subarea Plan Biological and Conference Opinions (WS-SDG-847.4) 70
Preserve, the MHCP Preserve with established linkages, will provide for the maintenance of
ecosystem function (e.g., pollinators, seed dispersers, etc.).
The MHCP Subregional Plan and the City’s Subarea Plan also provide avoidance, minimization, and
mitigation measures that will benefit plants. Standards criteria for planned and future development
projects include measures to avoid covered species. Additionally, those plants that are classified as
Narrow Endemic Species will have enhanced protections as described in the project description of this
Biological Opinion. Further, there will be management of the Preserve that will maintain or improve
habitat functions and values. In total, the MHCP Subregional Plan and the City’s Subarea Plan
provides for greater conservation of plants (listed or unlisted) than would occur without the MHCP.
Animals, General
It is anticipated that there will be direct and indirect effects impacting animals as a result of the
proposed action. Generally, these will be the same as the direct and indirect effects described above,
however, some species may be disproportionately impacted by certain effects.
Organisms with multiple life stages may be affected in different ways. For example, prior to
becoming adults, butterfly species &e susceptible to being crushed or trampled by off-road vehicles.
As adults, however, they are vagile and less likely to be impacted in the same way. Fairy shrimp
species face a similar situation; being more susceptible to crushing or trampling when they are cysts in
dry vernal pools. Fairy shrimp are further dependent on certain and specific hydrologic regimes that
may be impacted if the pool basin or its watershed is impacted. Likewise, amphibians have certain
hydrologic requirements in streams or ponds. They too may have different threats at different life
stages. These aquatic species may also be susceptible to impacts to water quality.
The MHCP Subregional Plan and the City’s Subarea Plan provide take avoidance, minimization, and
mitigation measures that will benefit animals. Standards criteria for planned and future development
projects include measures to avoid covered species in the Preserve. Additionally, specific
time-of-year restrictions (for certain species as described in MHCP Volume 2) prevent impacts to
nesting birds. Further, there will be management of the Preserve that will maintain or improve habitat
functions and values. The MHCP and the City’s Subarea Plan will provide additional benefits to
animals as a result of the creation and configuration of the City’s and overall MHCP Preserve. In
total, the MHCP Subregional Plan and the City’s Plan provide for greater conservation of animals
(listed or unlisted) than would occur without the MHCP.
Vernal Pool SDecies, General
Certain covered species (mostly in Table 3) depend upon vernal pools and their surrounding
watersheds as habitat. This section will serve as a general analysis for all of them. Vernal pool
species include San Diego button-celery, little mousetail, spreading navarretia, California Orcutt grass,
San Diego fairy shrimp, and Riverside fairy shrimp. Additional species that may be associated with
vernal pools include San Diego thornmint, thread-leaved brodiaea, and San Diego ambrosia. The
individual species evaluations provide further analysis.
Carlsbad Subarea Plan Biological and Conference Opinions @WS-SDG-847.4) 71
Habitat and Threats -
Vernal pools form in regions with Mediterranean climates where shallow depressions fill with water
during fall afid winter rains and then evaporate in the spring (Holland and Jain 1977). Vernal pools
have a discontinuous occurrence in several regions of California. Within San Diego County, vernal
pools are primarily found on the coastal terraces; however they do occur in the Ramona area and
inland mesa areas. .
Vernal pools require a unique combination of climatic, topographic, geologic, and evolutionary factors
for their formation and continued existence. Downward percolation is prevented by the presence of an
impervious subsurface layer, such as a claypan, hardpan, or volcanic stratum (Holland 1978). Due to
local topography and geology, the pools are usually clustered into pool complexes. Pools within a
complex typically are separated by distances on the order of meters and may form dense,
interconnected mosaics of small pools or a more sparse scattering of larger pools. Seasonal inundation
makes vernal pools too wet for adjacent upland plant species adapted to drier soil conditions, while
rapid drying during late spring makes pool basins unsuitable for typical marsh or aquatic species that
require a more permanent source of water. However, a number of indigenous plant and aquatic
invertebrate species have evolved to occupy the extreme environmental conditions found in vernal
pool habitats.
Vernal pools in San Diego County tend to be shallow, small, seasonally wet bodies of water located on
mesas, or on gently sloping landscapes which may contain broad, low hummocks known as
mima-mounds (Zedler 1987). Winter rains fill the shallow depressions and the resulting ponding is
sustained for varying amounts of time (Zedler 1987).
Threats to vernal pools can be divided into three major categories: 1) direct destruction of vernal pools
from construction, vehicle traffic, grazing, dumping, and deep plowing; 2) indirect threats that degrade
or destroy vernal pools (e.g. altered hydrology, draining, competition by introduced species, habitat
fragmentation); and 3) potential long-term, cumulative impacts such as the effects of isolation on
genetic diversity and locally adapted genotypes, air and water pollution, drastic climatic variations and
changes in nutrient availability (Bauder 1986). In addition, vernal pools in some areas (e.g., Otay
Mesa) are also affected by illegal immigration activities.
In San Diego County, historic loss of vernal pool habitat is estimated at 95 to 97 percent (Bauder
1986), with most of the remaining vernal pools still facing threats in the rapidly growing southern
California area. The loss of vernal pool habitat is nearly total in Los Angeles, Riverside and Orange
counties resulting in the ranking of vernal pool habitat in priority class G1-SI, which is reserved for
habitats which occur on less than 2,000 acres globally by the California Department of Fish and
Game’s Natural Diversity Data Base. The continuing destruction of vernal pools has resulted in
increased threats to all plant and animal species endemic to this ecosystem.
According to the information available to us, there are 29 acres of vernal pool habitat within the City
of San Marcos that are not addressed in the MHCP plan because the area is considered a major
amendment area. These pools are located along Las Posas Road north and south of Highway 78. San
Diego fairy shrimp are known to occur within these pools. We do not expect to find additional pools
in the MHCP Planning area and the City. However, pre-impact surveys to identify wetlands are
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 72
required which includes vernal pools. The only pools located outside of the City are within the major
amendment area for San Marcos.
Direct Efsects
There are only a few distinct areas with vernal pools within the MHCP Planning Area. These occur on
the Hiaett property, Manzanita Partners property, and Poinsettia Train Station of Carlsbad and the
major amendment area of San Marcos. As stated previously, direct impacts to covered species and
their habitat as a result of this action may only occur associated with the City’s Subarea Plan.
However, the City’s coverage for all of the vernal pool species is dependent upon ensuring they and
the California Department of Fish and Game have adequate access and funds to ensure the Poinsettia
Train Station pools are actively monitored and managed in accordance with Volumes 2 and 3 of the
MHCP.
The MHCP Subregional Plan and City’s Subarea Plan include measures to address potential vernal
pool impacts. In general, vernal pools would be defined as wetlands and the Wetlands Protection
Program requires that potential projects to be authorized under the Plan demonstrate that all wetlands
are avoided to the maximum extent practicable and that any unavoidable impacts are minimized and
then mitigated. The MHCP specifically identifies mitigation ratios in Table 4-7 of Volume 1 of 2: 1 to
4: 1 for vernal pools. However, all of the impacts (regardless of their location) will be minimized and
mitigated per the Wetlands Protection Program. Additionally, vernal pools, as a habitat, will benefit
from further avoidance, minimization, and mitigation measures associated with any Narrow Endemic
Species that might occur within those pools. More specifically, a condition of coverage for fairy
shrimp species in the plan is that all vernal pools and their watersheds within the MHCP be 100
percent conserved, regardless of occupancy of fairy shrimp and regardless of location inside or outside
of the FPA. More details are provided in the individual species analyses below. Please note, we
anticipate that there would be impacts to one vernal pool watershed on the Hiaett property as a result
of implementing the hardline as shown in the HMP.
Indirect Efsects
Vernal pools could be impacted by indirect effects both inside and outside of the Preserve. These
generally include all of the indirect effects mentioned in the “General Indirect Effects” section, above.
However, management of the Preserve will help reduce these indirect impacts. MHCP Volume 2 also
provides species specific standards which will be discussed in the appropriate species account, below.
CUMULATIVE EFFECTS
The Service must consider both the effects of the proposed action and the cumulative effects of other
activities in determining whether the action is likely to jeopardize the continued existence of a listed
species or result in the destruction or adverse modification of critical habitat. Cumulative effects are
defined as the effects of future State, local government, or private actions that are reasonably certain to
occur in the action area. Future Federal actions are not considered cumulative to the proposed action
because they require separate consultation pursuant to section 7 of the Act. Thus, Federally funded
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 73
projects such as the San LuisRey Flood Control Project and Caltrans/NCTD projects will not be
addressed in this Biological Opinion.
School Districts, Municipal Water Districts, San Diego Gas and Electric, and Caltrans are not an
applicant under the MHCP Subregional Plan. School Districts are actively planning development
within the MHCP boundaries that may significantly affect covered species. A high school is planned
for the City at the intersection of Cannon Road and College Boulevard. In addition, two schools are
pursuing development in the City of Oceanside at two separate parcels adjacent to the San Luis Rey
River. These projects would adversely affect gnatcatcher, vireo, flycatcher, and possibly arroyo toad.
Municipal Water Districts continue to propose and implement projects within the City and the MHCP
Planning area. These projects range from installing new sewer lines to maintaining water supply
pipelines and can have significant adverse effects on covered species.
In addition, there may be “non project” effects over which the City has limited or no control. We
anticipate that there may be conversion or degradation of habitat within the action area (which extends
beyond the City’s jurisdictional authority) resulting from agricultural and grazing use, off-road vehicle
activity, illegal dumping, and impacts associated with illegal aliens. Furthermore, non-native grass
and weed growth may also degrade existing habitat and affect covered species. Native plants may be
out-competed by non-native plants, especially if weed growth is disproportionately facilitated (as
compared to native vegetation) by the deposition of nitrogen compound fertilizers that have their
origins as atmospheric pollutants. Non-native grasses and weeds are typically annual species, which,
when they die, can provide additional fuel and may increase the frequency or severity of wildfires.
Weeds typically also respond more quickly to fire or other disturbance and thereby convert one habitat
type to another (e.g., coastal sage scrub converting to non-native grassland). If dead annual weeds
build up, the resulting thatch may change microsite characteristics further affecting seed germination
or plant growth. Thatch may also restrict movement of small animals. These impacts have the
potential to be substantial but are difficult to quantify. However, the Cities will be monitoring and
managing their respective portions of the MHCP Preserve. The management is anticipated to reduce
or otherwise mitigate these potential effects. Additional impacts may result from human-induced
changes in the climate, however, the actual affects that may occur from such changes are, at this point,
speculative and unforeseeable.
.
Based on the preceding general analysis and the following analysis of each species’ current status and
environmental baseline, the anticipated direct, indirect, and cumulative impacts, the following
summarizes the Service’s Biological and Conference Opinions regarding effects of the proposed
issuance of a section lO(a)( 1)(B) incidental take permit to the City pursuant to the MHCP Subregional
Plan, the City’s Subarea Plan, and all associated documents.
Recovery
The City’s Subarea Plan is consistent with the MHCP Subregional Plan, which was developed to meet
the NCCP goals of providing for high likelihood of persistence of target species and providing for no-
net-loss of habitat value from the present. The NCCP Conservation Guidelines define no-net-loss of
habitat value as “. . . no net reduction in the ability of the subregion to maintain viable populations of
target species over the long-term.” The guidelines clarify that “the goal of no-net-loss of habitat value
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 74
may be attainable even if thele is a net loss of habitat acreage, provided that the preserve design is
adequate and techniques are employed to manage and restore the preserved habitat.” The Subarea
preserve design is consistent with the seven basic tenets of preserve design outlined in the
Conservation Guidelines, and preserve management will be provided through species-specific and
site-specific land-use and management guidelines to ensure that the preserve’s biological values are
maintained in perpetuity. The permanent protection and management provided under the plan will
allow for the recovery of covered species by: a) supporting the persistence of narrowly ranging
covered plant and wildlife species within the planning area whose survival is dependent upon
persistence in this area; b) contributing to the long-term habitat viability of vegetation communities for
species dependent on these communities; and c) contributing to the overall conservation of
wide-ranging species through the protection of large, interconnected blocks of habitat rather than the
small patches that will result from project-by-project mitigation. The species-by-species accounts
below may also provide additional information regarding the Plan’s contributions to the species’
recovery. All species identified in Tables 1,2,3 and 4 that have a recovery plan were analyzed to
ensure that the City’s HMP and the MHCP Subregional Plan would not preclude recovery of the
species.
INCIDENTAL TAKE
Section 9 of the Act and Federal regulations pursuant to Section 4(d) of the Act prohibit the take of
endangered and threatened species, respectively, without special exemption. Take is defined as to
harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to engage in any such
conduct. Harm is further defined by the Service to include significant habitat modification or
degradation that results in death or injury to listed species by significantly impairing essential
behavioral patterns, including breeding, feeding, or sheltering. Harass is defined by the Service as
intentional or negligent actions that create the likelihood of injury to listed species to such an extent as
to significantly disrupt normal behavior patterns which include, but are not limited to, breeding,
feeding, or sheltering. Incidental take is defined as take that is incidental to, and not the purpose of,
the carrying out of an otherwise lawful activity. Under the terms of Section 7(b)(4) and Section
7(0)(2) of the Act, takmg that is incidental to and not intended as part of the Agency’s action is not
considered to be prohibited taking under the Act provided that such taking is in compliance with the
terms and conditions of this Incidental Take Statement.
As noted above, direct impacts to Covered Species and their habitats are anticipated to only occur
within the City of Carlsbad as a result of this action because each City within MHCP will be applying
for an individual permit under section lO(a)(l)(B) of the Act. Thus, this Opinion and associated
incidental take statement will not exempt take associated with the MHCP Subregional Plan that is not
caused by the issuance of the City’s proposed HMP. The City’s proposed HMP and its associated
documents identify anticipated effects to covered species likely to result from the proposed take and
the measures included in the HMP and MHCP Volume 1 and 2 to help minimize and mitigate those
impacts. All conservation measures described in the proposed HMP, MHCP Volumes 1,2, and 3,
together with the terms and conditions described in the associated IA and any future Section .
lO(a)( 1)(B) permit issued with respect to the proposed MHCP and HMP, are hereby incorporated by
reference as terrns and conditions within this Incidental Take Statement pursuant to 50 CFR (i). Such
terms and conditions are non-discretionary and must be undertaken for the exemptions under Section
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 75
lO(a)(l)(B) and Section 7(0){2) of the Act to apply. If the permittee fails to adhere to these terms and
conditions, the protective coverage of the Section lO(a)(l)(B) permit and Section 7(0)(2) may lapse.
The “AmouIlt or Extent of Take” for each animal species identified in Tables 1,2, and 3, is included in
the species-by-species evaluations, below. The Act does not prohibit the take of listed plant species,
consequently, Section 7(b)(4) and 7(0)(2) of the Act do not apply to the listed plants. The “Amount of
Extent of Take” for each species in Table 4 has not been identified because the City is not requesting
coverage for these species. Nevertheless, the Service must make a section 7(a)(2) finding for each
species and critical habitat that is likely to be adversely affected by the proposed action.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 76
SPECIES-BY-SPECIES EVALUATIONS
SPECIES FROM TABLE 1: These are species that the City will receive coverage immediately after
the permit is issued. Because take will only occur associated with the MHCP Subregional Plan
once a City receives a permit, we will be providing a take statement only for those animals
species as they relate to the Carlsbad Subarea Plan.
Chorizanthe orcuttiana (Orcutt’s spineflower)
Status of the Species
Listing Status
Orcutt’s spineflower was listed as federally endangered on October 7, 1996 (61 FR 52370) and is
also listed as endangered by the State of California. The MHCP classifies this species as narrow
endemic. This species is on theCalifornia Native Plant Society’s list 1B with a R-E-D (Rarity-
Endangerment-Distribution) code of 3-3-3, and a California Natural Diversity Data Bank ranking
of GlS 1.1.
Species Description
Orcutt’s spineflower, a member of the Polygonaceae (buckwheat) family, was first described by
Charles Pany (1884) based on a specimen collected by Charles Orcutt in March 1884 in Point
Loma, San Diego County. Orcutt’s spineflower is a prostrate annual with stem branched from
base into stems 3-10 cm long. Basal leaves are spathulate with long petioles and stems with
lanceolate, leaf-like bracts in opposite pairs. Flowers solitary or in tiny clusters in cymules
(involucres). Each flower is reverse pyramid-shaped with the floral tube 3-ribbed and bearing
long hooked spines. Whitish petal-like calyx barely exerts from the involucre. It is distinguished
from other members of the genus by its prostrate form, campanulate three-toothed involucre and
involucral awns that are hooked near the tip.
Distribution
The range of Orcutt’s spineflower appears to be limited to western San Diego County along the
coast (Bauder 2000). Its historical distribution included 10 known locations in Encinitas, Del
Mar, Point Loma, and Kearny Mesa (CDFG 1992). A population has recently been rediscovered
in Point Loma (V. Scheidt pers. comm.). However, the only confirmed extant MHCP location
for this species in recent years is a very small population (e40 individuals) in Oak Crest Park in
Encinitas.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 77
Habitat Afin ity
Orcutt’s spineflower occurs in open patches of sandy soil or under the canopy edge of
surrounding perennial shrubs (Bauder 2000). Typically, these sandy openings in shrublands
occur in relatively flat areas at the toe of coastal bluffs. The soil type is mapped as Carlsbad
gravelly loamy sand (Bowman 1973). Associated species may include Torrey pine (Pinus
torreyana ssp. torreyana), California sagebrush (Artemisia californica), sage (Salvia spp.),
California buckwheat (Eriogonurn fasciculatum) and goldenbrush (Haplopappus spp.) (Bittman
1991).
Life History
Bauder (2000) describes Orcutt’s spineflower as developing a small rosette of narrowly
oblanceolate leaves during the vegetative stage in late fall to early spring. Later in the
reproductive stage (generally April), the species bolts and the branched inflorescence extend
upwards and outwards 6-10 cm. More research is needed to determine important pollinators for
this species, but a literature review by Bauder (2000) of other Chorizanthe species demonstrate
that a wide variety of small insects, including ants, parasitic wasps, and solitary bees, are possibly
important pollinators (Bauder 2000).
Population Trend
Bauder (2000) reviewed the records of the 12 Element Occurrence (EO) of Orcutt’s spineflower
in the California Department of Fish and Game’s Natural Diversity Data Base (NDDB 1998).
Eight of these records were found to be credible, whereas the others were either erroneous or
duplicates. After visiting the eight credible sites, Bauder discovered that only three sites still
contained extant populations. Two of these populations were located in Point Loma and the third
population was located in Oakcrest Park in Encinitas. All other populations were presumed
extirpated. In Oakcrest Park, surveys conducted in April 1997 identified approximately 75 plants
(Eliason, pers. comm. 1997), an increase over the population estimate of 20 individuals made in
1992 (Reiser 1996). However, this increase may not be considered indicative of an improving
population since the number of individuals varies widely from year to year since the success of
germination is highly dependent on factors such as rainfall (U.S. Fish and Wildlife Service
1996).
Threats
Development for residential or military uses and heavy disturbance from foot traffic in open
sandy areas in coastal chaparral communities were the primary factors that reduced the historical
distribution of this species. Urban development continues to threaten the remaining potential
habitat within the cities of San Diego, Del Mar, Solana Beach, and Encinitas (Reiser 1996). The
known populations in Point Lorna are threatened by exotic species, namely Carpobrotus edulis
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 78 -
and acacia cultivars (Bauder 2000). The population in Oakcrest Park is at high risk because it is
located niar an actively-used community park and faces threats from several anthropogenic
disturbances (Bauder 2000).
Environmental Baseline
The Orcutt's spineflower has only one known occurrence within the MHCP. This location is in
Encinitas and is on preserved land. There are no known populations in the Carlsbad subarea.
This species occurs on open, sandy areas within southern maritime chaparral. In a recent
investigation of potential habitat for Orcutt's spineflower researchers found that most of the
potential habitat in Carlsbad had already been lost to development (Bauder 2000).
Effects of Action
Direct Efsects
The MHCP subregional plan requires the following conditions be met before a City can receive
coverage for this species:
1.
2.
3.
4.
5.
6.
At least five self-sustaining, distinct populations' must be conserved within the species
geographic range (including 100% of extant populations and the majority of all newly
discovered, naturally occurring populations and artificially initiated populations) before
any loss is allowed
The MHCP Narrow Endemic Policy must be applied to any populations of this species,
including those already known and any found in the future.
All conserved populations must be managed for genetic considerations as a
metapopulation.
Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g., germination if the species is determined to be fire-dependent) while
protecting individual plants and habitat from frequent or high-intensity fires and fire
suppression activities.
A seed bank must be established as a guarantee against extinction and to provide source
material for conservation and research activities. Collections should be based on
established guidelines and subject to seed availability. Collected seed should be stored at
an established seed bank facility (e.g. Rancho Santa Ana Botanic Garden).
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat to
improvement activities. Unless analyses determine that there is no significant genetic
variation between populations, introduced plant materials must be from the parental
population or a population in proximity.
' The five self-sustaining populations do not necessarily need to be within the MHCP study area, but do need to be
situated within the known distributional range of this species and/or within suitable habitat (i.e., MSCP and MHCP study
areas).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 79 -
7.
8.
As part of the review process (e.g., CEQA) for individual projects within the MHCP area,
a qualified biologist must survey for this species in all potential habitat areas.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
Self-sustaining populations are defined as those that retain genetic resources necessary to undergo
adaptive evolutionary change (Guerrant 1996). Determination of a viable or self-sustaining
population shall be assessed through long-term monitoring (e.g., 5 to 10 years) and shall include
demographic measures (e.g., the number of individuals or viable seeds in a population is stable or
increasing over time) and genetic measures (e.g., changes in overall genetic diversity as measured
against a baseline genetic profile) (Primack 1996; Falk et al. 1996). Self-sustaining populations
should contain a minimum of 1,000 individuals to reduce the risk of extinction from intrinsic or
random events, unless research or monitoring indicates that higher or lower population numbers are
appropriate for this species. In addition, self-sustaining populations should occur within blocks of
natural habitat that are large enough (i.e., >50 acres) to support appropriate pollinators and buffer
the conserved population from edge effects.
Thus, the MHCP Subregional plan will only allow loss of this species after at least five self-
sustaining, distinct populations are conserved. Even after these populations are conserved, the
plan only allows for up to 20 percent loss through the narrow endemic policy.
There are no direct effects expected from the Carlsbad subarea plan because Orcutt’s spineflower
is not know from the Carlsbad subarea. If Orcutt’s spineflower is found in the subarea it will be
preserved. This plant is listed as one of the narrow endemic species. Because this plant is a
narrow endemic, new populations of this plant found within the preserve hardline and softline
areas will be completely preserved and populations found outside this area will be conserved at a
minimum of 80 percent.
Zndirect Efsects
If new populations of this species are found in the City, any indirect effects would be addressed
through the monitoring and management requirements identified for this species.
Conclusion
We have concluded that the MHCP Subregional Plan and City’s Subarea Plan will not directly
impact Orcutt’ s spineflower. The avoidance, minimization, and/or mitigation measures included
in the MHCP Subregional Plan and City’s Subarea Plan and the monitoring and management that
will occur consistent with the MHCP Management and Monitoring Plan (Volume 3) will reduce
any indirect impacts that may occur to this species. This species will also benefit from the
habitat that the MHCP Subregional Plan will preserve in perpetuity. This Preserve will be
adaptively managed, per the measures included in the MHCP Subregional Plan and the City’s
Subarea Plan which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 80 -
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the h&HCP Subregional Plan and the City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
Dudleya blochmaniae ssp. blochmaniae (Blochman’s dudleya)
- Status of the Species
Listing Status
Blochman’s dudleya is neither a State nor a Federally listed species. This species is on the
California Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code
of 2-3-2, and a California Natural Diversity Data Bank ranking of G2T2S2.1.
Species Description
Blochman’s dudleya, a member, of the Crassulaceae (stonecrop) family, was originally described
by Alice Eastwood (1896) as Sedum blochmanae based on a specimens collected by her and Mrs.
Ida Blochman in May 1896 in clay soil along the road to Pt. Sal, Santa Barbara County.
Afterwards, the taxonomic status of the species underwent several revisions until Moran’ s
(1953) currently accepted taxonomic description of the species as Dudleya blochmaniae.
Blochman’ s dudleya is a small succulent perennial containing drought deciduous leaves, stems
arising from a globose or oblong underground corm-like tuberous caudex, and divergent petals
and carpals. This subspecies produces white flowers with red or purple markings with spreading
petals on short stalks.
Distribution
Blochman’ s dudleya currently ranges discontinuously from near San Simeon in central California
to northwestern Baja California, west of the town of Colonet (Dodero 1995). Despite its
relatively widespread distribution in the Counties of San Diego, Orange, Los Angeles, Ventura,
Santa Barbara, and San Luis Obispo in California, this species is known from fewer than 20
occurrences and fewer than 5 occurrences in Baja California (Skinner and Pavlik 1994).
Dodero’ s (1995) phylogenetic analysis revealed three separate evolutionary lineages within the
species’ range, the central California populations from Santa Barbara County northward to San
Luis Obispo County, the southern California populations from the Santa Monica Mountains
southward through Orange County to San Diego County, and the Baja California populations.
In San Diego County, the species is found on Camp Pendleton, and within the Cities of
Oceanside and Carlsbad. The population in Carlsbad is currently the southernmost population of
this subspecies within the County. This population is small, comprised of less than 100
individuals. The species historically ranged as far south as Pacific Beach, but was extirpated by
development (Dodero 1995).
Habitat AfJinity
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 81
Blochmai’s dudleya is typically found on coastal bluffs in association with coastal scrub habitat.
It has also been reported on rocky or clay soils unsuitable for many other more common native
plants.
Life History
Blochman’s dudleya is a herbaceous perennial plant that flowers between April and June (Reiser
1996). According to Dodero (1995), population sizes vary greatly from year to year and appear
to be closely dependent on rainfall and temperature. Also, the timing of rainfall has an important
role in the number of individuals that eventually flower. For example, prolonged dry periods
during midwinter following significant rains in December and January may cause some plants to
become dormant and decrease the number of successfully flowering individuals. Potential
pollinators include honey bees (Apis mellifera), bumble bees (Bombus spp.), digger bees (Family
Anthophoridae), bembicine wasps (Stenolia duplicata), and (Bembix occidentalis), metallic
sweat bees (Family Halictidae), bee flies (Family Bombyliidae), bee mimic flower flies (Family
Syrphidae) and soft-winged flower beetles Dasytes spp. (Family Melydridae) (Dodero 1995).
Population Trend
According to Reiser (1994), Blochman’s dudleya is substantially declining throughout it’s range
in southern California range.
Threats
Habitat loss is the primary threat to Blochman’s dudleya due to its affinity for coastal habitats
and large amounts of development along coastal areas in southern California. Trampling by
humans, edge effects associaled with development, invasion of exotic plants, and fires may also
impact extant populations.
Environmental Baseline
Blochman’s dudleya is known from three locations in the MHCP; two are in the City of
Oceanside and one location in the Carlsbad subarea. One of the locations in Oceanside is
considered a major population as well as a critical location. The population in Carlsbad is
considered a critical location. This population is located on the Heiatt property, just to the west
of Palomar airport. It is possible that other populations of this plant exist in Carlsbad in areas
that have not been specifically surveyed for this species. Because this plant is small and
ephemeral it is hard to detect and considered cryptic.
Effects of Action
Direct Efiects
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 82 -
The MHCP subregional plan requires the following conditions be met before a City can receive
coverage ’for this’species:
1.
2.
3.
The major and critical population in Oceanside must be conserved at a level consistent
with the critical location policy and managed as part of the preserve system.
Fire management plans must be implemented for all conserved populations to protect
them from frequent and high-intensity fires and fire suppression activities.
Declining populations in the FPA must be enhanced, and damaged habitat restored, if
determined necessary through monitoring. Enhancement may include introduction of
plant materials to existing populations, while restoration may include site-specific habitat
to improvement activities. Unless analyses determine that there is no significant genetic
variation between populations, introduced plant materials must be from the parental
population or a population in proximity.
As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist must survey for this species in all potential habitat
areas.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
4.
5.
In the MHCP planning area, three of the five point locations are within the FPA. However, any
points outside the FPA do not receive any protection. Overall 50 percent of the major
populations and 63 percent of critical locations of this species will be conserved via the FPA.
The major and critical populations in Oceanside will be conserved under the critical location
policy. In addition, 309 acres (49 percent) of potential Blochman’s dudleya habitat will be
conserved by the MHCP.
The single known population of this plant in Carlsbad will not be directly impacted by the project
and is in an area that currently has funding for management. There is a possibility that new
populations of Blochman’s dudleya will be found as surveys are conducted on sites with suitable
habitat.
Indirect Eflects
This plant could be indirectly impacted by the implementation of this plan. The creation of
impervious surfaces associated with the development (for example, on the Heiatt property) could
alter the hydrology. This could increase the amount of runoff to Blochman’s dudleya. Increased
water in-turn could alter the plants’ habitat by increasing exotic plant cover, changing the soil
composition, or creating erosion. There is the possibility that the plant could be adversely
effected as a result of shading from exotic plants or encroaching landscape plants. Another
indirect effect that could adversely impact Blochman’s dudleya is the fragmentation of the
surrounding landscape. This could effect the survival and effectiveness of pollinators and
decrease the gene flow with other populations of Blochman’s dudleya.
Conclusion
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 83 -
We have concluded that the MHCP Subregional Plan will directly impact Blochman’s dudleya.
As much’as 50 percent of the population in Oceanside could be impacted, however, the critical
location policy must be applied and as a result, greater conservation should occur for this
population. The MHCP Subregional Plan will also impact up to 51 percent of habitat suitable for
Blochman’s dudleya. The City’s Subarea Plan will not directly impact Blochman’s dudleya, but
up to 39 percent of suitable habitat in the City will be directly impacted. The avoidance,
minimization, and/or mitigation measures included in the MHCP Subregional Plan and City’s
Subarea Plan and the monitoring and management that will occur consistent with the MHCP
Management and Monitoring Plan (Volume 3) will reduce any indirect impacts that may occur to
this species. This species will also benefit from the habitat that the MHCP Subregional Plan will
preserve in perpetuity. This Preserve will be adaptively managed, per the measures included in
the MHCP Subregional Plan and the City’s Subarea Plan which will further reduce the indirect
effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
Euphorbia misera (Cliff spurge)
Status of the SDecies
Listing Status
Cliff spurge is neither a State nor a Federally listed species. This species is on the California
Native Plant Society’s list 2 with a R-E-D (Rarity-Endangerment-Distribution) code of 2-2-1 and
a California Natural Diversity Data Bank ranking of G5S3.2.
Species Description
Euphorbia misera, a member of Euphorbiaceae (spurge) family (Koutnik 1996), was first
described by George Bentham (1844). Cliff spurge is a low growing erect shrub (5-10
decimeters), with small (0.4-1.5 centimeter) ovate to round hairy leaves. Leaves are entire and
are arranged alternately. White flowers are produced terminally, one per branch. The fruit is a
capsule with a white or gray seed.
Distribution
Cliff spurge is found in Orange, Riverside, and San Diego counties; on San Clemente and Santa
Catalina islands in Los Angeles County; and on the mainland and Isla Guadalupe in Baja
California, Mexico (Skinner and Pavlik 1994). In San Diego County, this species is known from
Carlsbad, Point Loma, San Diego, Sweetwater Valley, and Otay Mesa. It also occurs in the
border region known as Tijuana Hills (Beauchamp 1986). Carlsbad currently supports the only
known population in the MHCP planning area.
Hub itat AfJin ity
Carlsbad Subarea Plan BioIogicaI and Conference Opinions (FWS-SDG-847.4) 84 -
Cliff spurge is found on rocky slopes and coastal bluffs in coastal scrub (e.g., coastal bluff scrub,
maritime hcculent scrub, coastal sage scrub).
Life History
Cliff spurge is a shrub (stem succulent) that presumably is not particularly well adapted to fire
because of its succulence. It is insect-pollinated (Crepet 1983) and seeds are self-dispersed.
Flowering occurs between May and June.
Population Trend
According to Reiser (1994) populations of cliff spurge in the United States are stable. The City
of Carlsbad does not support major populations of this species nor do historical records indicate
this species was common in the area. The sole population of cliff spurge in Carlsbad appears to
be stable due to the full protection that it will receive within the Focused Planning Area.
Threats
The primary threats to this species are development and associated edge effects. Cliff spurge is a
stem succulent species and therefore it is susceptible to fires.
Environmental Baseline
There is only one population known within the MHCP. The population is on the north edge of
Agua Hedionda Lagoon to the west of interstate 5 in the Carlsbad subarea. The population is
adjacent to the Windsong Shores property. This population is in a strip of land bordered by
water, roads and development. There is very little opportunity for this population to expand. It is
possible that this population provides a stepping-stone for genetic transfer between the
populations north and south of Carlsbad, outside of the MHCP. This population is not
considered major or a critical location.
Effects of Action
Direct Eflects
The MHCP subregional plan requires the following conditions be met before a City can receive
coverage for this species:
1. Fire management plans must be implemented for all conserved populations to protect
them from frequent and high-intensity fires and fire suppression activities. If determined
necessary to maintain the population, develop fire management guidelines within
conserved areas that limit fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 85
The population of cliff spurge will not be directly effected by the MHCP Subregional Plan or
City’s Subarea Plan because it is in the FPA and will be 100 percent conserved. It is possible
that this plant exists at on areas of coastal bluff habitat that have not been surveyed in detail.
Although most of the suitable habitat has already been developed, cliff spurge might be found on
the coastal slopes near the three lagoons in Carlsbad. The MHCP Subregional Plan will conserve
1,183 acres (69 percent) of potential cliff spurge habitat.
Indirect Eflects
The single population of cliff spurge is on a narrow strip of conserved habitat. It is likely that
this population will be indirectly impacted by foot traffic and run-off water from developed areas
nearby. The MHCP Subregional Plan and City’s Subarea Plan will monitor and manage for such
potential adverse effects. Management is expected to occur initially via lagoon management by
California Department of Fish and Game at Agua Hedionda Lagoon.
Conclusion
We have concluded that the MHCP Subregional Plan and City’s Subarea Plan will not directly
impact cliff spurge because the single population of cliff spurge will be 100 percent conserved
and monitored and managed in a fashion that will detect and minimize any negative impacts that
are affecting cliff spurge. The avoidance, minimization, and/or mitigation measures included in
the MHCP Subregional Plan and City’s Subarea Plan and the monitoring and management that
will occur consistent with the MHCP Management and Monitoring Plan (Volume 3) will reduce
any indirect impacts that may occur to this species. This species will also benefit from the
habitat that the MHCP Subregional Plan will preserve in perpetuity. This Preserve will be
adaptively managed, per the measures included in the MHCP Subregional Plan and the City’s
Subarea Plan which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 86
Hazardia orcuttii (Orcutt’s hazardia)
Status of the Species
Listing Status
Orcutt’s hazardia is not a state or federal listed species. This species is on the California Native
Plant Society list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 3-3-2, and a
California Natural Diversity Data Bank ranking of GlG2S 1.1. The MHCP considers this species
to be narrow endemic.
Species Description
Hazardia orcuttii is a member of Asteraceae (sunflower) family. It is a resinous shrub (5-10
decimeters in height) rising from a woody trunk. Leaves are oblanceolate to narrow obovate and
abruptly pointed. Ray flowers are yellow. The fruit that is produced consists of a white to
reddish brown achene.
Distribution
Orcutt’s hazardia is known from only one site in the United States, but is locally common along
the coastal plains from Colonet to Tijuana in Baja California (Clark 1979). The only known
United States’ population for this species occurs in the Manchester Preserve, City of Encinitas,
San Diego County.
Habitat Afinity
The Orcutt’s hazardia population in Encinitas is associated with chaparral and coastal sage scrub
on loamy alluvial soils of the Huerhuero complex (Reiser 1996).
Life History
Orcutt’s hazardia, a small resinous shrub, is presumably fire-adapted, although the fire response
mechanism is unknown. Flowers are insect-pollinated and seeds are presumably animal-
dispersed. This species flowers between August and October.
Population Trend
Reiser (1996) indicated that the one known U.S. population had experienced site degradation
from 1986 to 1989. This site was further disturbed in 2000 when a private landowner
transplanted approximately 260 naturally occurring individuals from his property to the
Manchester Preserve so that it would not impede future development of his property.
Approximately 80 plants survived the relocation effort. This population was further degraded in
2000 when the Encinitas Fire Department accidentally cleared occupied Hazardia orcuttii habitat
during training exercises (Kim Marsden, pers. corn.).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 87
Threats ’
Threats to this species include urbanization and associated edge effects. Habitat fragmentation
may also threaten this species in the United States. Although Orcutt’s hazardia likely has some
adaptation to fire, it may be adversely affected by unnatural fire regimes (e.g., frequent fires,
high- intensity fires resulting from fire suppression policies), particularly where they result in a
type conversion of native habitat andor invasion of habitat by nonnative weedy species.
Environmental Baseline
Orcutt’s hazardia is only known to occur naturally at one location in the MHCP. This single
population is located in the Manchester Preserve in Encinitas, managed by the Center for Natural
Lands Management, and is considered a major population and a critical location in the MHCP.
Orcutt’s hazardia occurs in chaparral, including southern maritime chaparral, and coastal sage
scrub. There are 17,978 acres of these habitat types in the MHCP planning area.
It is possible that Orcutt’s hazardia occurs in the Carlsbad subarea and has not yet been
discovered. If found in Carlsbad, Orcutt’s hazardia would likely be in southern maritime
chaparral or coastal sage scrub. It is possible that the preserve area in Carlsbad may provide
suitable habitat for future introductions of Orcutt’s hazardia.
Effects of Action
Direct Efsects
The MHCP subregional plan requires the following conditions be met before a City can receive
coverage for this species:
1.
2.
The MHCP narrow endemic policy must be applied to any populations of this species,
including those already known and any found in the future.
Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel
reduction methods in urban areas), while limiting fire frequency and emergency access.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat to
improvement activities. Unless analyses determine that there is no significant genetic
variation between populations, introduced plant materials must be from the parental
population or a population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
3.
4.
No impacts to this species will occur from the MHCP Subregional Plan because the only known
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 88
population is located within a preserve. In addition, the narrow endemic policy and critical
location policy will minimize impacts to any new locations. The MHCP Subregional Plan will
impact 34 percent of suitable Orcutt’s hazardia habitat. The City’s Subarea Plan will not directly
impact Orcutt’s hazardia because it is not know from the Carlsbad subarea. If Orcutt’s hazardia
is found in the subarea it will be preserved via the narrow endemic species.
Indirect Effects
The single population in the MHCP at the Manchester Preserve in Encinitas is vulnerable to edge
effects, such as trampling and invasion of exotic species, and vulnerable to unnatural fire
regimes.
Conclusion
We have concluded that the MHCP Subregional Plan will not directly impact Orcutt’s hazardia,
and the narrow endemic and critical location policy must be applied to any new populations. The
MHCP Subregional Plan will impact up to 34 percent of habitat suitable for Orcutt’s hazardia.
The City’s Subarea Plan will not directly impact Orcutt’s hazardia, but up to 31 percent of
suitable habitat in the City will be directly impacted. The avoidance, minimization, and/or
mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan and the
monitoring and management that will occur consistent with the MHCP Management and
Monitoring Plan (Volume 3) will reduce any indirect impacts that may occur to this species.
This species will also benefit from the habitat that the MHCP Subregional Plan will preserve in
perpetuity. This Preserve will be adaptively managed, per the measures included in the MHCP
Subregional Plan and the City’s Subarea Plan which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline
for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not
likely to jeopardize the continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 89
Quercus durnosa (Nuttall’s scrub oak)
Status of the SDecies
Listing Status
Nuttall’s scrub oak is neither a State nor a Federally listed species. This species is on the
California Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code
2-3-2, and a California Natural Diversity Data Bank ranking of G2S 1.1.
Species Description
Nuttall’s scrub oak, a member of the Fagaceae (oak) family, was first described by Nuttall
(1842). It is an evergreen shrub, 1-3 meters tall, with multiple trunks, and branches that are often
sharply angled and a deep reddish-brown. Leaves are 10-25 mm long, usually short, round
outline or slightly longer than broad, with shiny green upper surfaces and dull pale green
undersides covered with fine, densely matted gray hairs (becoming sparse with age), and with
abruptly pointed teeth or spines. Acorns are 10-20 mm, long, narrow, and tapered to a pointed
tip.
Distribution
Nuttall’s scrub oak has a disjunct distribution that includes Santa Barbara, Orange, and San
Diego counties (Skinner and Pavlik 1994). The species also occurs southward along the coastal
hills of Baja California, Mexico to Punta Banda and the vicinity of San Vicente (Roberts 1995).
In San Diego County, Nuttall’s scrub oak has been documented below 500- meter (1,640 feet)
elevation in Carlsbad, Encinitas, Questhaven, Solana Beach, and San Dieguito County Park.
Populations of this species are fairly well defined along the immediate coast, but not well defined
further inland. Along the coast in San Diego County, Nuttall’s oak occurs in Carlsbad (Agua
Hedionda, vicinity of Green Valley) and Encinitas (vicinity of Green Valley, Lux Canyon).
Nuttall’s scrub oak was recently segregated from Q. berberidifoliu by Nixon and Steele (1981).
Habitat AfSinity
Nuttall’s scrub oak generally occurs in sandy soils near the coast, in association with chaparral
and coastal sage scrub at elevations less than 500 meters.
Life History
Acorn crops are generally light, although larger crops are produced at irregular intervals (Keeley
1981). Production appears to vary by the individual tree. Some plants consistently bear large
numbers of acorns, while others rarely produce acorns (Plumb et al. 1983). Acorns are readily
dispersed in the fall by gravity or animals (Keeley 1981, 1987). Squirrels and jays are
particularly effective dispersal agents for many California oak. Acorns mature within a single
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 90
season and germinate readily without scarification or other special treatment (Keeley 198 1).
Establishment of Nuttall’s scrub oak through seed appears to be uncommon despite consistent
acorn production (Keeley 1981, Plumb 1982). Nuttall’s scrub oak typically sprouts vigorously in
response to fire, mechanical injury, or other types of disturbance (Plumb 1961).
Population Trend
The prolific expansion of urban development along the coast has resulted in a decline in the
species’ populations.
Threats
The primary threats to this species are development and associated edge effects.
Environmental Baseline
Nuttall’s scrub oak occurs in chaparral and coastal sage scrub in Carlsbad, Encinitas, and Solana
Beach. There are 16,980 acres of these habitats throughout the MHCP planning area. There are
three major populations of Nuttall’s scrub oak that occur within the MHCP. Two of the three
major populations occur in the Carlsbad subarea; one is in central Carlsbad and the other is on
the southwestern border with Encinitas. There is another population located on the City’s golf
course property and east of the Veteran’s Park property.
The population in central Carlsbad occurs on several properties. Among those are Carlsbad
Forum, Carlsbad Oaks North, Bressi Ranch, and the county property east of the airport. This
species lost several point locations in the development of Bressi Ranch and the Carlsbad Forum.
However, some of the Nuttall’s scrub oak on Bressi Ranch is now in a hardline preserve. Within
this central Carlsbad population there are point locations that occur on Carlsbad Oaks North and
two point locations west of El Camino Real.
The other major population is located on the boundary of Carlsbad and Encinitas. The portion of
this population that occurs in Carlsbad is located to the east of El Camino Real in a relatively
narrow strip of habitat. This strip of habitat is part of the existing preserve as the result of a
completed project .
Effects of Action
Direct Effects
The MHCP subregional plan requires the following conditions be met before a City can receive
coverage for this species:
1. The major population and critical location at Agua Hedionda in Carlsbad must be
conserved at a level consistent with the critical location policy and managed as part of the
preserve system.
Fire management plans must be implemented for all conserved populations to promote 2.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 91 -
biological goals (e.g. regeneration) while protecting individual plants and habitat from
friquent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel
reduction methods in urban areas), while limiting fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
3.
A majority (68 percent) of the species points in the MHCP planning area fall within the PA.
Overall, 86 percent of major populations of this species will be conserved. Of the three major
and critical populations, two will be conserved 100 percent and the third will be conserved at a
level consistent with the critical location policy due to the above conditions of coverage. The
MHCP plan conserves 11,140 acres (66 percent) of Nuttall’s scrub oak habitat. Any occurrences
found outside of the FPA will not be conserved per the MHCP, however, the City has a no-net-
loss of woodland policy that should benefit this species.
The majority of the point locations for Nuttall’s scrub oak in Carlsbad are in areas that are no
longer considered for the analysis of this plan because the impacts have already been permitted.
However, the population on the Golf Course property will be impacted by this plan since the
oaks occur outside of the hardline preserve; it is possible that some of the actual plants belonging
to this population are within the hardline preserve. Some individual plants in this population
occur east of the Veteran’s Park property. These individuals occur within the proposed hardline
preserve. Of the point locations that are part of the central Carlsbad and in the subarea, one is
located in a standards area and the other is in an area in the proposed hardline preserve. Within
the standards area there is a policy of no-net-loss of oak woodlands, which will provide
protection for the Nutall’s scrub oak in this area. Nearly all the major and critical locations are
within managed areas. The City does not currently have access and funds for the Green Valley
area, but only one occurrence is found here.
Indirect Effects
Nutall’s scrub oak subpopulations are disconnected and this fragmentation will limit the transfer
of genetic information and limit the ability of seed moving vectors to distribute seeds. The
remaining habitat will be constrained and vulnerable to edge effects. Increased foot traffic and
unchecked run-off from development may alter the habitat to the degree that the seedlings of
Nutall’s scrub oak will have difficultly becoming established. Management and monitoring
included in the plan will benefit this species and likely control these negative effects.
Conclusion
We have concluded that the MHCP Subregional Plan and City’s Subarea Plan will directly
impact Nuttall’s scrub oak. The MHCP allows losses of Nuttall’s scrub oak in the Cities of
Carlsbad, Encinitas, and Solana Beach and any newly found populations outside of the FPA. In
the City of Carlsbad, it is unclear the extent to which they will be impacted, but it is assumed
they will be only partially impacted. The MHCP Subregional Plan and City’s Subarea Plan will
provide monitoring and management of this species that will detect and minimize negative
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 92 -
impacts that are Nuttall’s scrub oak. The City will provide management and monitoring initially
for nearl; all of the major populations and critical locations in the City. Additionally, this
species should benefit from the connected preserve system that will be managed and monitored
in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed,
per the measures included in the MHCP Subregional Plan, which will further reduce the indirect
effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 93
Panoquina errans (Salt marsh skipper)
Status of the Species
Listing Status
There is no State or Federal listing for this species. The CNDDB ranks this species as G2G3S1
and the World Conservation Union classifies it as a low risk, but near threatened species.
Species Description
Considerable confusion exists regarding the scientific and common name of this butterfly.
Panoquina errans is closely related to P. panoquinoides, which occurs along the Gulf Coast of
Texas and Florida (MacNeill 1975). It is frequently treated as a subspecies of P. panoquinoides
(Emmel and Emmel 1973), but MacNeill(l975) and others consider P. errans as distinct as the
former. Panoquina errans was long known as the “wandering skipper”. The salt marsh skipper
wing span is 2.5 - 3.2 centimeters with an olive-brown upperside and a row of small clear spots
on the forewing. Hindwings are without marlungs and the underside is brown with a short
curved row of 3-5 pale spots (Opler et al. 1995).
Distribution
The salt marsh skipper is widely distributed along the narrow coastal strand from Santa Barbara
County south to the southern tip of Baja California, Mexico (Brown 1991) and also occurs on
mainland western Mexico (Opler et al. 1995). They occur in nearly all of the coastal lagoons in
San Diego County (Ogden Environmental 1998).
Habitat Afinities
The salt marsh skipper is restricted to coastal salt marshes and coastal estuaries. Adults are
commonly associated with seashore saltgrass (Distichlis spicata ssp. spicata) (Brown 1991,
Opler et al. 1995), the dominant larval host plant (Brown 1991). Studies conducted at the
Tijuana Estuary (Busnardo 1989) indicate that larvae occur at highest frequency and density on
saltgrass, but may be found rarely on cordgrass (Spartinafoliosa) and Bermuda grass (Cynodon
dactylon). The latter situation probably is the result of mistaken oviposition by females (Brown
1991). Due to the apparently tolerant and invasive nature or D. s. spicata, occasional colonies of
salt marsh skipper have persisted despite minimal habitat alteration (Brown 1991). The salt
marsh skipper appears to prefer lower and wetter rather than drier areas of the salt marsh
(Busnardo 1989). According to Busnardo (1989), some of the most commonly used nectar
sources for adults in the Tijuana Estuary include introduced species such as heliotrope
(Heliotropium cuwassavicum), sea rocket (Cakile maritima), sea-fig (Carpobrotus spp.), and
chrysanthemum (Chrysanthemum coronariurn); native species that act as nectar sources include
deerweed (Lotus scoparius), salty Susan (Jaumea carnosa), and frankenia (Frankenia spp.)
(Brown 198 1).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 94
Life Histiry
Awaiting receptive females, the males will perch on beach grasses. Females lay eggs on the host
and on other plants and caterpillars spend the day in shelters of rolled or tied leaves and feed on
leaves at night. They are in flight from June-September in California.
Population Trend
Hix (1990) estimated that the acreage of coastal salt marsh habitat in San Diego County has been
reduced by 87.8 percent of its former coverage. Brown (1991) reasoned that the populations of
salt marsh skipper have likely declined at rates similar to the habitat loss rates in San Diego
County.
Threats
The major threats to the species are from urbanization, road construction, off-road vehicular
traffic, trampling, edge effects and lack of natural tidal flushing in lagoons (Ogden
Environmental 1998).
Environmental Baseline
Within the MHCP planning area, this species occurs in salt marsh and saltpan habitats within
Encinitas, Carlsbad, and Oceanside. Both adults and larvae are frequently associated with salt
grass (Distichlis spicata) but have also been observed in association with other plant species.
The salt marsh skipper occurs in salt marsh habitat associated with nearly every coastal lagoon in
San Diego County. The salt marsh and saltpan habitats in Encinitas, Carlsbad, and Oceanside are
considered major populations and critical locations.
Under the City’s Subarea Plan there 15 1 acres of potentially suitable habitat (southern coastal salt
marsh). Population and distribution information for this species is limited within the Subarea
due to a lack of survey effort, but it has the potential to be present in salt marshes and salt pans,
especially since one observation of this species was documented at Aqua Hedionda Lagoon.
Effects of the Action
Direct Effects
The MHCP Subregional Plan requires that for a city to receive coverage for this species they
need to maintain natural tidal flushing of lagoons to maintain sufficient saltgrass habitat for the
species. Periodic dredging may be required to open lagoon mouths, as indicated by results of
monitoring.
The MHCP Subregional Plan will have little to no direct impacts to salt marsh skippers because
the one known population in Carlsbad will be conserved and the critical locations in Encinitas
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 95
and Oceanside are included in hardline preserve areas that will be 100 percent conserved.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of
estuarine and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of
estuarine habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777
acres of estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are
approximately 5.5 acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua
Hedionda Lagoon associated with the Interstate 5 right-of-way, which are not included in the
preserve since the City does not have ultimate control of these areas. The State Route 101 and
railroad rights-of-way across Buena Vista Lagoon are also not included in the preserve. There
are no projects proposed for this area, however, impacts may occur in the future in the right-of-
ways due to projects such as road widening which would be beyond the control of the City. Such
impacts would be analyzed and permitted under a different mechanism than the MHCP. A small
amount of additional habitat in the lagoons are also technically not in the mapped area of the
preserve, however, no projects are planned for this area by the City and 100 percent conservation
due to MHCP standards for avoidance, minimization, and mitigation of wetland impacts assure
no-net-loss of lagoon wetland habitat. However, impacts can occur to such wetland communities
as described in section 3.6 of MHCP Volume 1. Since such impacts would need to be fully
mitigated according to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will
occur in MHCP, although there could be a temporal loss of such functions and values. The
MHCP conditions for estuarine species and fact that all the lagoons are in the coastal zone, also
provide more protection to the lagoon areas. Due to these standards, any losses would only be
temporal and no net decrease in lagoon habitat (estuarine, salt marsh, etc.) would occur as a
result of the City’s Subarea Plan. In addition, direct take of animal species is expected to be
minimized because any areas proposed for disturbance would be avoided where MHCP species
or nests are known or found to be present.
Indirect Efsects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse affects to salt marsh sluppers within the Subarea. These
indirect impacts include night lighting, human disturbance, and habitat degradation, as generally
explained and applicable in the “General Indirect Effects” section.
Specifically, indirect impacts to the salt marsh skippers could result from the degradation of salt
marsh habitats. Alterations to the hydraulic regime of salt marshes and degradation of water
quality (dredging, non-point source run-off> may impact the composition and abundance of
available host plants and nectar sources. Also, increased freshwater flow could decrease the
salinity of salt- or brackish-marshes, thus leading to degradation of necessary habitat. The
MHCP Subregional Plan addresses this issue in th condition for coverage described above. In
addition, the City’s Subarea Plan provides a basis for the conservation of this species and it’s
associated habitats. Specifically, Table 9 of the Subarea plan states:
Manage preserve areas to minimize edge effects, control invasive non-native plants,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 96
maintain Saltmarsh hydrology and water quality, and protect Saltmarsh habitat from
physical disturbances. Where opportunities arise, restore and enhance habitat in preserve
areas. Control exotic plants. Preserve habitat adjacent to the lagoons to the maximum
extent possible.
The long-term preserve management plan shall provide area specific management
directives for salt marsh habitats, including specific adaptive management measures to
protect against detrimental edge effects from adjacent development, recreational impacts,
and other direct and indirect impacts.
Implementation of the Subarea plan does not address increasing the amount of tidal flushing in
Buena Vista Lagoon, which is necessary for this species survival. Buena Vista Lagoon is the
only coastal estuarine waterbody that does not currently posses this interaction.
Conclusion
We anticipate the MHCP Subregional Plan and the City’s Subarea Plan will directly and
indirectly affect this species. Nearly all of the salt marsh skipper habitat is within the FPA and it
should also be protected by the no-net-loss of wetland policy. The MHCP Subregional Plan and
City’s Subarea Plan will provide monitoring and management of this species that will detect and
minimize negative impacts that are affecting salt marsh skippers. The City will provide
management and monitoring initially for all but one major population and critical location of this
species and once funding is available, will manage and monitor all locations. Additionally, this
species should benefit from the connected preserve system that will be managed and monitored
in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed,
per the measures included in the MHCP Subregional Plan, which will further reduce the indirect
effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual salt marsh skippers associated
with temporal loss of up to 17 acres of southern coastal salt marsh habitat will be taken in the
form of harm as a result of the City’s subarea plan. However, this number is expected to be low
because of the no-net-loss of wetland policy and the critical location policy. In addition, the City
and managers of the lagoons will need to maintain sufficient saltgrass habitat and maintain
natural tidal flooding in the lagoons. Thus, the City’s subarea plan will not jeopardize the
continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 97
Euphyes vestris harbisoni (Harbison’s dun skipper)
Listing Status
On June 4, 1991, the Service received a petition dated May 27, 1991, to list the Laguna
Mountains skipper (Pyrgus ruralis lagunae), Hermes copper butterfly (Lycaena hemes),
Harbison’ s dun skipper (Euphyes vestris harbisoni), and Thorne’s hairstreak butterfly (Mitoura
thornei). Harbison’s dun slupper currently has no Federal or State designation as a listed species.
Its CNDDB rank is GSTlS1.
Species Description
Euphyes vestris harbisoni was formally recognized as a subspecies in 1983 based on
dissimilarities of habitat preferences and it’s relative size (Brown and McGuire 1983). It is the
largest subspecies of dun skipper (E. vestris) with forewing length range is from 15.0 to 16.1 mm
(% = 15.2 mm) in males and 14.7 to 17.0 mm (X = 16.0 mm) in females. Its body is dark brown
with the forewing chocolate-brown above. Also on the upper side of the forewing is lustrous
orange over-scaling near two black oval patches forming a broken dash. The outer margin of the
forewing has a light tan over-scaling and no additional markings. On the underside, the forewing
is dull brown, with basal and distal blackening. The hindwings are also dull brown below but
with no markings (Brown and McGuire 1983).
Distribution
The Harbison’s dun skipper occurs in a series of scattered and disjunct colonies throughout
western San Diego County, extending as far north as the Silverado Canyon area of Orange
County. The San Diego County localities include Dulzura, Flinn Springs, Old Viejas Grade,
Otay Mountain, the northern slope of Tecate Peak, Fallbrook, east of Valley Center and San
Pasqual (Brown 1991). All populations found by Brown and McGuire (1983) were below 650
meters. Its range is restricted in part by the distribution of the larval host plant, San Diego sedge
(Carex spissa). Its distribution in Baja California, Mexico is unknown, but its host plant does
occur there (Brown and McGuire 1983). There is one documented historic observation in the
Subarea at Aqua Hedionda Lagoon in Carlsbad.
Habitat Afinity
The habitat occupied by the southern California population is remarkably dissimilar to that of all
other known populations of E. vestris. The southern California population is extremely local,
generally occurring in chaparral or riparian communities in narrow canyons where there is a seep
or spring providing perennial water. The oviposition substrate and larval host plant is San Diego
sedge, with which the adults are commonly associated. Adults are also attracted to nectar
sources which include morning glory (Calystegia macrostegia tenuifolia), red thistle (Cirsium
occidentale), loosestrife (Lythrum californicurn), and rarely, golden yarrow (Eriophyllum
confertiporurn) and black mustard (Brassica nigra) (Brown and McGuire 1983).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 98
Life History
The southern California population of Euphyes vestris is single-brooded. During April and May
of each year, eggs are laid singly. Eggs are usually placed on the underside of the leaves, at the
base of the Carex spissa plant. Young larvae are found on the mid-ridge crease of the upper
surface of the leaves, near the base of the plants. The second and third instar larvae are found,
when not eating, in silk-lined tubes constructed by the larvae by attaching two to four leaves
together longitudinally. During the fourth instar, or occasionally the third instar, the larvae
construct an overwintering hibernaculum (protective chamber) and enter a short diapause. During
the final instar, the larvae consumes the end of the hibernaculum and moves to a different location
on the plant, or to a different plant to pupate. Pupation lasts 18 to 21 days. Adults emerge from
late May through June, and the flight period extends into early July (Brown and McGuire 1983).
Population Trend
Brown and McGuire (1983) in their original description of the subspecies noted that several of the
populations they found were stable, but all were “extraordinarily small.” Some of the prior known
colonies have been extirpated by construction projects and other habitat modifications (Brown and
McGuire 1983) and it is assumed that the total population has declined as a result of these
activities, however, more data is needed to assess the magnitude of this decline. A large
population formally existed in the Adobe Falls area near San Diego State University.
Encroachment by development, the introductions of pollutants into Adobe Creek, and competition
from invasive non-native plants together eliminated the host plant (Brown and McGuire 1983).
The once-large colony at Flinn Springs has been adversely affected by the development of Flinn
Springs County Park. Where the stand of C. spissa has been reduced to a few plants supporting
an equally reduced population of the Harbison’s dun skipper (Brown and McGuire 1983).
Threats
The major population threat to Harbison’s dun skipper is from destruction of riparian habitat
(Brown and McGuire 1983, Opler et al. 1995). Habitat loss through development, introduction of
pollutants, and competition from invasive non-native plants have resulted in the loss of the host
plant and thus Harbison’s dun skipper (U.S. Fish and Wildlife Service 1993). Drought and
scouring floods may also eliminate or negatively impact host plants (US. Fish and Wildlife
Service 1993).
Environmental Baseline
Within the MHCP planning area, Harbison’s dun skipper is known from north and east Escondido
and adjacent to south San Marcos (Elfin Forest area). The populations in Escondido are
considered major populations and critical locations.
Within the City of Carlsbad, population and distribution information for this subspecies is limited
due to a lack of survey effort. However, the Harbison’s dun skipper butterfly has an unlikely
presence in the Subarea and is not known to occur within 10 miles of the coast. Connectivity of
Carlsbad Subarea Plan Biological and Conference Opinions (F’WS-SDG-847.4) 99
preferred habitat is scattered throughout the Subarea as oak woodland and riparian areas are
commoniy disassociated from one another. The Subarea Plan contains approximately 603 acres
of suitable habitat for the subspecies.
Effects of the Action
Direct Efsects
The MHCP requires the following species specific conditions be met by a city to receive coverage
of this subspecies:
1. As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist must survey, using approved survey techniques, all areas
containing suitable habitat (oak woodlands and riparian areas, especially those supporting
Carex spissa). Surveys shall be conducted when impacts could occur as a result of direct
or indirect impacts by placement of a project in or adjacent to suitable habitat. Surveys
should occur prior to any proposed impact both within and outside of the FPA.
2. Projects within the FPA shall restrict activities that could degrade Harbison’s dun
skipper habitat by modifying stream flow, degrading water quality, or introducing
nonnative plants or predators into riparian systems.
3. Projects having direct or indirect impacts to Harbison’s dun skipper shall adhere to the
following measures to avoid or reduce impacts:
a) Avoid and minimize removal of native vegetation to the maximum extent
practicable. Determination of adequate avoidance and minimization of impacts
shall be consistent with Sections 3.6 and 3.7 of the MHCP plan. Deviations from
these guidelines shall require written concurrence of the USFWS and CDFG. For
temporary impacts, the work site shall be returned to preexisting contours and
revegetated with appropriate native species. All revegetation shall occur at the
ratios specified in Section 4.3 of the MHCP plan. All revegetation plans shall be
prepared and implemented consistent with Appen&x C (Revegetation Guidelines)
and shall require written concurrence of the USFWS and CDFG. If written
objections are not provided by the wildlife agencies within 30 days of receipt of
written request for concurrence by the local jurisdiction, then the deviation may
proceed as approved by the local agency. The wildlife agencies shall provide
written comments specifying wildlife agency concerns.
b) Projects shall be carried out consistent with Appendix B (Standard Best
Management Practices ) .
c) Maintain biological buffers of at least 100 feet adjacent to occupied Harbison’s
dun skipper habitat, measured from the outer edge of oak woodland or riparian
vegetation. Within this 100-foot buffer, no new development shall be allowed, and
the area shall be managed for natural biological values as part of the preserve
system. Buffers less than 100 feet shall require written concurrence of the USFWS
and CDFG within 30 days of receipt of request for written concurrence from the
local jurisdiction.
d) Where impacts cannot be totally avoided, larvae and possibly adults shall be
salvaged for relocation or other research or management purposes under guidance
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 100
of the wildlife agencies.
4. Manage suitable unoccupied habitat to maintain or mimic effects of natural fluvial
processes (e.g., periodic substrate scouring and deposition).
5. Maintain natural riparian connections with upstream riparian habitat to ensure linkages
to suitable habitat within the North County MSCP Subarea and City of San Diego MSCP
Subarea.
Seventy-six percent of Harbison’s dun skipper habitat is within the €FA for the MHCP
Subregional Plan. In addition, all three point localities are within the FPA. The critical locations
and major populations in the City of Escondido are included in hardline preserves and will be 100
percent conserved. Overall, the MHCP Subregional Plan will conserve 3,364 acres (95 percent)
of suitable habitat for this subspecies due to the no-net-loss of wetland policy.
The City’s €FA includes 25 acres (86 percent) oak woodland and 494 acres (86 percent) riparian,.
with anticipated impacts to 2 acres (9 percent) oak woodland and temporal loss of 76 acres (14
percent) riparian as a result of this plan. We anticipate few direct impacts to this subspecies based
on the absence and improbability of this subspecies in the Subarea and the amount of suitable
habitat preserved.
Please note that the impacts to riparian vegetation identified above would be subject to the MHCP
standards for avoidance, minimization, and mitigation of wetland impacts to assure no-net-loss of
wetlands. Impacts can occur to,such wetland communities as described in section 3.6 of MHCP
Volume 1. Since such impacts would need to be fully mitigated according to section 4.4.2 of
MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there could be a
temporal loss of such functions and values.
Indirect Effects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse affects to Harbison’s dun skipper within the action area.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets,
and habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
Specifically, any impacts to San Diego sedge (Carex spissa) may pose indirect impacts to
Harbison’s dun skippers. Impacts such as competition from exotic species, water quality
degradation, pesticide applications, and fluvial alterations can indirectly impact the host plant.
The City’s Subarea Plan provides a basis for the conservation of this subspecies and it’s
associated habitats. Specifically, Table 9 of the Subarea plan states:
Manage preserve areas to minimize edge effects, control non-native plants, maintain
hydrology and water quality, and protect habitats from physical disturbances. Restrict
human activities in occupied habitat. Ensure that impacts to any population found
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 101 -
constitute less than 87 percent of the population. Mitigation for any unavoidable impacts
should include translocating any individuals by transplanting whole San Diego sedge
plants to appropriate habitat. Translocation should be supervised by a qualified biologist.
The long-term preserve management plan shall provide area specific management
directives for the host plant (Carex spissa), including specific adaptive management
measures to protect riparian areas against detrimental edge effects from adjacent
development, recreational impacts, and other direct and induect impacts. Carex spissa
should be considered for use in wetland restoration projects where soil and water
conditions are appropriate to increase the population of Harbison’s Dun Skipper.
Management is expected to occur initially via lagoon management by California Department of
Fish and Game at Agua Hedionda Lagoon.
Conclusion
We anticipate the MHCP Subregional Plan will directly and indirectly affect this species through
habitat loss from development. However, a majority (76 percent) of the Harbison’s dun skipper
habitat is within the FPA and it should also be protected by the no-net-loss of wetland policy. The
City’s Subarea Plan is not expected to directly affect this species since the species is not known to
occur in Carlsbad and there may not be any suitable habitat in the City. The MHCP Subregional
Plan and City’s Subarea Plan will provide monitoring and management of this subspecies that will
detect and minimize negative impacts that are affecting Harbison’s dun skippers. Additionally,
this subspecies should benefit from the connected preserve system that will be managed and
monitored in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively
managed, per the measures included in the MHCP Subregional Plan, which will further reduce the
indirect effects and benefit the subspecies. After reviewing the current status of this subspecies,
the environmental baseline for the action area, the effects of the proposed action, and the
cumulative effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the
City’s Subarea Plan are not likely to jeopardize the continued existence or recovery of this
subspecies.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual Harbison’s dun sluppers will
be taken in the form of harm as a result of the City’s subarea plan within a maximum of 5 acres of
oak woodland habitat and through temporal loss of 76 acres of riparian habitat. This number is
expected to be low because no occurrences are known in the City, 99 percent of their habitat will
be conserved, and the species will benefit from the no-net-loss of wetland and wetland buffer
policies. The incidental take is expected to be in the form of harm, harassment, and death. Thus,
the City’s subarea plan will not jeopardize the continued existence or recovery of this subspecies.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 102
Pelecanus occidentalis califomicus (California brown pelican)
Status of the SDecies
.
- Listing Status
The California brown pelican was federally listed as endangered in 1970 (35 FR 16047) and listed
as endangered by the State of California on June 27, 1971. No critical habitat has been designated
for this species, however a recovery plan was adopted in 1983. This is a fully protected species by
the State.
Species Description
Pelecanus occidentuh (brown pelicans) are recognized by their large size, impressive wingspan
(up to 2 meters), short legs, distinctive long, hooked bill and flexible lower mandible from which
the highly expandable gular pouch is suspended. Six subspecies of P. occidentalis have been
described; geographic variation in size is the primary distinguishing feature (Wetmore 1945).
Unlike other brown pelican subspecies, P. o. califomicus typically has a bright red gular pouch
(basal portion) during the courtship and egg-laying period (U.S. Fish and Wildlife Service 1983).
Distribution
The current breeding distribution of California brown pelicans range from the Channel Islands of
southern California southward to Isla Isabela, Islas Tres Marias off Nayarit, Mexico, and Isla
Ixtapa off Acapulco, Guerrero, Mexico (U.S. Fish and Wildlife Service 1983). Between breeding
seasons, pelicans may range as far north as Vancouver Island, British Columbia and south to
Central America (Palmer 1962). There are no known coastal nesting colonies in San Diego
County.
Habitat Afinity
The California brown pelican is typically found in marine habitats which range from the open
ocean to inshore waters, estuaries, bays, and harbors. This species may also use large freshwater
lakes when they are near the coast (e.g., Sweetwater Reservoir). Pelicans commonly use
undisturbed beaches, breakwaters, and jetties near coastal bays as roosting areas and forage
nearby. They tend to breed on offshore islands and will nest on the ground or in small bushes and
trees (American Ornithologists’ Union 1983).
Life History
Brown pelicans are diurnally active throughout the year. In California, brown pelicans feed
mainly on northern anchovy (Engruulis rnordax), Pacific sardine (Surdinopus sagax), and Pacific
mackerel (Scornberjaponicus houttuyn) (Thelander and Crabtree 1994). Brown pelicans
generally forage in early morning or late afternoon, or when the tide is rising. They feed almost
entirely on fish, caught by diving from 6-12 meters in the air, and occasionally from up to 20
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 103 -
meters. They may completely, or only partially, submerge in shallow or deep water. Feeding is
often con'centrated in shallow waters of less than 50 fathoms (300 feet) (Gress et al. 1980).
Occasionally brown pelicans will feed on crustaceans, carrion, and young of its own species
(Palmer 1962). They usually rest on water or inaccessible rocks (either offshore or on mainland),
but will also use mudflats, sandy beaches, wharves, and jetties. At night, they concentrate at a few
traditional roosts on mainland or islands, but have been known to roost overnight on water (Briggs
et al. 1981).
California brown pelicans are colonial nesters, and breeding is typically initiated in late December
or early January. The nest is a small mound of sticks or debris on rocky, or low, brushy slopes of
undisturbed islands (Cogswell 1977); usually on the ground, but less often in bushes (Palmer
1962). After breeding, they begin migrating as early as mid-May. Individuals leave colonies in
the Channel Islands and in Mexico, and disperse along the entire California coast. Small numbers
visit the Salton Sea and Colorado River reservoirs. Most return to breeding colonies by March or
April. During the nesting season, they generally stay within 20 kilometers of nesting islands
(Briggs et al. 1981). Nests are spaced a minimum distance of approximately 1.5 meters apart
(Palmer 1962). Brown pelicans are present at nesting islands March to early August, and lay eggs
March to April, but possibly as late as June (Palmer 1962). Clutch size is usually 3 eggs,
sometimes 2 with a single brood each year. Incubation lasts about 4 weeks. Young are altricial
and tended by both parents and first fly between 10 and 13 weeks. Brown pelicans first breed at
about 3 years.
Gulls, especially the Hermann's, frequently steal fish from pouches of brown pelicans
immediately after a dive. Gulls and vultures are typical nest predators, and eggs and nestlings
sometimes are lost in storms (Palmer 1962).
Population Trend
At the time the recovery plan was published (1983), it was estimated that the breeding population
size throughout the range was approximately 55,000 to 60,000 pairs (U.S. Fish and Wildlife
Service 1983). This species declined considerably in the late 1960s (Garrett and Dunn 198l),
attributed to the use of organochlorine pesticides (e.g., DDT, DDE, DDD), disturbance of nesting
colonies, and over-harvesting of northern anchovies, the major food source (Garrett and Dunn
198 1). The ecological effects of DDT contamination have not been entirely eliminated, and
incidences of eggshell thinning still occur. While low-level, chronic contamination remains,
populations of brown pelicans in the southern California area have been increasing since the late
1970s. This population increase may be from outside recruitment and improved reproduction in
local populations (Anderson and Gress 1983). Between 1983-1993, five-year means of number of
California brown pelican nesting attempts in the Southern California Bight have increased from
less than 2,700 to over 4,700, suggesting that the breeding population has increased comparably
during that period (Gress, unpublished data). In southern California, brown pelican colonies are
found only on Anacapa and Santa Barbara islands; they do not nest on any of the other Channel
Islands. The breeding population of brown pelicans in southern California is estimated at 4,500 to
6,000 pairs. Some genetic exchange occurs among colonies by the recruitment of new breeders.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 104
The largest breeding group is located on the Gulf of California, comprising approximately 68
percent of the total breeding population.
- Threats
Food availability, disturbance, and oceanic pollution currently appear to be the major limiting
factors to populations of California brown pelicans (U.S. Fish and Wildlife Service 1983).
Potential threats related to these limiting factors include commercial fisheries, oil development,
recreational fisheries, sonic booms and increased tourism (U.S. Fish and Wildlife Service 1983).
The Santa Barbara Channel has been the site of offshore petroleum drilling. The potential of oil
well blowouts and the effects of resultant oil spillage in the Channel Islands area was observed in
the 1969 Santa Barbara oil spill, although the spill did not reach Anacapa Island and had little
impact on breeding pelicans (Service 1983). Further oil development in the Santa Barbara
Channel may pose a threat to the brown pelican colony at West Anacapa Island. There are several
lease tracts overlapping with Channel Islands Marine Sanctuary boundaries.
Pelicans and their eggs fouled with oil have been observed on numerous occasions in the SCB and
Gulf of California. Trace amounts of fresh oil transferred from feathers to eggs is lethal to
embryos in a variety of waterfowl species. If an oil spill occurred during fledging time when
young pelicans congregate in large numbers on the water near colony sites and washed up on
shore, the impact could be detrimental to young pelicans and mortality could certainly occur
(Service 1983). The Santa Barbara Channel also has numerous natural oil seeps which represent
another source of fouling (Service 1983). The risks to pelicans associated with an oil spill is not
limited to the breeding season. During the fall and winter thousands of migrant pelicans from
Mexico flood the SCB and could be greatly affected by a major oil spill. The impact of an oil
spill on brown pelicans is influenced by the size of the spill, the time of the year, the type of oil,
the distance offshore of the spill, and the environmental conditions at the time of the spill.
The Santa Barbara Channel and the coast just north of Point Conception have current petroleum
development in local proximity to brown pelican colony or roost sites. There has been a concern
about the potential adverse environmental effects of oil and gas development in these coastal areas
which has led to a moratorium on new oil and gas development and drilling along the California
coast. The Channel Islands National Marine Sanctuary has helped buffer the West Anacapa Island
colony from the threats of petroleum industry accidents (Service 1983). In the event of an oil
spill, the buffer zone would provide time and distance for break-up of oil discharges before
reaching nearshore communities, as well as increase available response time. The sanctuary
provides a 6-mile (9.7 km) zone within which new petroleum operations are prohibited. The
sanctuary has little effect on development of the few existing leases within sanctuary boundaries
that existed prior to the creation of the marine sanctuary in 1980. Currently there are no platforms
within the marine sanctuary.
Marine sanctuary regulations allow cargo-carrying vessels, including oil tankers, to operate to
within one nautical mile of Anacapa island. Most cargo vessels stay within the established
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 105
shipping lanes in the Santa Barbara Channel, but their compliance is not mandatory. The
northbouhd shipping lane passes within 8 to 9.7 km (5 to 6 mi) of Anacapa Island while the
southbound shipping lane passes within a 1.6 to 3.2 km (1 to 2 mi) distance of East Anacapa
Island. Because of greater probability of a spill occurring from a tanker than from a platform, the
possibility of tanker traffic outside the established sea lanes as close as one nautical mile from
Anacapa poses a potential threat to brown pelicans (Service 1983).
Federal laws regulating offshore oil and gas operations have also been more stringent in recent
decades. The oil content of water produced from offshore operational dscharges is limited by
effluent guidelines promulgated by EPA, which are enforced by National Pollution Discharge
Elimination System permits. The Minerals Management Service (MMS) is responsible for day-
to-day inspection and monitoring of Outer Continental Shelf (OCS) oil and gas operations and
monitoring hydrocarbon discharges resulting from such operations. Additionally, an
Environmental Impact Statement must be prepared for all MMS and OCS lease sales.
Environmental Baseline
The California brown pelican is a year round resident of coastal water bodies and beaches of
southern California, but is not known to have nesting colonies within the mainland of southern
California, including the City of Carlsbad (majority of nesting occurs on the Channel Islands).
While no local brown pelican breeding colonies are in close proximity to the MHCP planning
area, pelicans forage in the nearshore waters of the Pacific Ocean, and Aqua Hedionda Lagoon is
one of the known roosting areas (Merkel & Associates 1995). The lagoon systems and coastal
habitat in the Subarea plays an important role in the foraging and roosting needs of this species.
Documented observations of this species have been made at Buena Vista Lagoon, Aqua Hedionda
Lagoon, San Elijo Lagoon and Batiquitos Lagoon. The Carlsbad-Oceanside-Vista Annual
Christmas Bird Count (which includes all of the coastal areas of the Carlsbad Subarea, plus other
areas outside of the Subarea), yielded 475 California brown pelicans in 2002 (National Audubon
Society 2002). The average number counted in this survey, since 1970, has been 134 per year.
Aqua Hedionda Lagoon was initially dredged in 1954 to provide a source of cooling water for San
Diego Gas & Electric Company’s Encina Power Plant. Since 1954, the outer lagoon has
undergone periodic maintenance dredging, while no dredging had occurred in the middle and
inner lagoons. The outer lagoon is dredged every one to three years. Initial dredging, and the
ongoing maintenance dredging program, may have affected sediment deposition within the
lagoon, therefore affecting potential pelican roosting habitat.
Batiquitos Lagoon has also experienced extensive restoration, including dredging. Restoration of
this seasonal tidal waterbody was initiated in 1994 and completed in 1996. It resulted in the
continuous tidal exchange of Pacific Ocean waters. Dredge spoils were used as beach
nourishment north of the lagoon. The inlet channel to Batiquitos Lagoon was also dredged in
2000. Pelicans use the lagoon for roosting or loafing, and the restoration may have affected
pelican habitat.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 106
Buena Vista, Agua Hedionda, and Batiquitos lagoons contain approximately 934 acres of
estuarine’and salt marsh habitats that support or potentially support California brown pelicans.
Effects of the Action
Direct Eflects
MHCP Subregional Plan requires the following condition be met for a city to receive coverage for
this species: No take of individuals, roosts, or nests is permitted for this fully protected species.
Reserve management must control access to avoid harassment in roost areas. In addition, all
foraging habitat and all known location points in the study area are within the FPA which means
no development is proposed for these areas and they will be managed and monitored in perpetuity.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of
estuarine and coastal salt marsh habitat (15 1 acres of coastal salt marsh habitat and 783 acres of
estuarine habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777
acres of estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are
approximately 5.5 acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua
Hedionda Lagoon associated with the Interstate 5 right-of-way, which are not included in the
preserve since the City does not have ultimate control of these areas. The State Route 101 and
railroad rights-of-way across Buena Vista Lagoon are also not included in the preserve since
Caltrans and the Federal Highway Administration is not a participant to this MHCP. Any impacts
that may occur in the future in these right-of-ways due to projects such as road widening would be
analyzed and permitted under a different mechanism than the MHCP.
A small amount of additional habitat in the lagoons are technically not in the mapped area of the
preserve, however, no projects are planned for this area by the City and 100 percent conservation
due to MHCP standards for avoidance, minimization, and mitigation of wetland impacts assure
no-net-loss of lagoon wetland habitat. However, impacts can occur to such wetland communities
as described in section 3.6 of MHCP Volume 1. Since such impacts would need to be fully
mitigated according to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will
occur in MHCP, although there could be a temporal loss of such functions and values. The
MHCP conditions for estuarine species and fact that all the lagoons are in the coastal zone, also
provide more protection to the lagoon areas. Due to these standards, any losses would only be
temporal and no net decrease in lagoon habitat (estuarine, salt marsh, etc.) would occur as a result
of the City’s Subarea Plan. In addition, indirect effects will be minimized because any areas
proposed for disturbance would be avoided where MHCP species are found or known to be
present or roosting. All of the suitable brown pelican roosting habitat on artificial tern nesting
islands and mud flats in the lagoons is included within the preserve. The preserve includes nearly
all of the open water in the lagoons, which may occasionally serve as pelican foraging habitat.
Thus, because brown pelicans do not nest in the MHCP planning area and there will be no-net-
loss of foraging area, and the quality of foraging habitat will not be significantly degraded due to
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 107
the conditions for estuarine species, no direct impacts to brown pelican are expected from
implemen’ting the MHCP nor the HMP.
Indirect Efects
Indirect impacts have the potential to cause significant adverse affects to the California brown
pelican within the action area. These indirect impacts include noise effects, changes in hydrology
from adjacent development, and increased lighting, as generally explained and applicable in the
“General Indirect Effects” section.
Specifically, indirect impacts to the California brown pelican could result from the degradation of
water quality in coastal lagoon systems. Contaminants that may affect aquatic organisms,
including pelican prey species, in the lagoons may be carried to the lagoon by storm water runoff
from throughout the watershed. Developed areas are sources of non-point source pollution.
Development also increases the amount of impervious surface in the watershed, increasing the
velocity and volume of storm water runoff, thus exacerbating conveyance of non-point source
pollution in storm water runoff. Therefore, development throughout MHCP planning area may
adversely affect California brown pelicans and their lagoon habitat.
Turbidity plumes, generated by the runoff of silt and fine sediments into the lagoons or Pacific
Ocean from erosion due to development upstream from lagoons, may obscure available forage
fish in the lagoons or nearshore ocean waters that potentially could be preyed upon by pelicans.
This issue of water clarity is significant given that the brown pelican is a sight feeder. Schreiber
et al. (1975) believed that pelicans select individual fish, even if it is in a school. Even if schools
of fish utilized by brown pelican are not totally obscured, turbid water conditions could adversely
affect foraging success of brown pelicans. The potential of reducing the local food supply would
be most significant to juvenile pelicans that have been shown to have a first year mortality rate of
70 percent (Schreiber 1998). However, the conditions for estuarine species requires specific
measures to be implemented to prevent and minimize sedimentation into the lagoons.
Indirect effects may also occur from increases in human disturbances at beach and coastal areas,
associated with conversion of agricultural areas to urban uses at the proposed Hub Park at the
southeast comer of Agua Hedionda Lagoon and the farmland at the northeast comer of Batiquitos
Lagoon. Management is expected to occur initially via lagoon management by California
Department of Fish and Game at Agua Hedionda Lagoon.
The Subarea plan provides a basis for the conservation of this species and its associated habitats
by requiring the following:
1.
2.
No take of individuals, roosts, or nests is permitted for this fully protected species.
Reserve management must control access to avoid harassment in roost areas.
Manage preserved areas to minimize contamination by pesticides, oil, and other pollutants;
reduce disturbances at important foraging and roosting areas, and maintain lagoon
hydrology and water quality (e.g.; 100 foot setback from existing wetland habitats).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 108
3. The long-term preserve management plan shall provide area-specific management
diiectives for the major resting areas at Agua Hedionda, Buena Vista and Batiquitos
Lagoons, including specific adaptive management measures to address water quality and
protect against detrimental edge effects from adjacent development, recreational impacts,
and other direct and indirect impacts.
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must
be implemented to ensure coverage of species (including the California brown pelican)
dependent on estuarine habitats. These measures are intended to minimize indirect
impacts to pelicans and other estuarine species. Measures include regulation of adjacent
land use, recreational access, mosquito control, noise, vehicle access, potential pollutants,
access during breeding season, camping and picnicking; area-specific management
measures including fencing, animal and plant pest control, habitat enhancement and/or
creation, trash removal, erosion control, maintenance of tidal flushing; monitoring of
covered species populations, biodiversity, habitat area, effect of recreation on wildlife, pest
animal and plant populations, use by migratory birds, and success of restoration efforts;
and development of public awareness program including public participation in
management, development of community outreach programs, and improvement of trails
and facilities to focus public access.
4.
Conclusion
We anticipate the proposed action will not directly impact brown pelicans due to the conditions of
coverage for this species and the no-net-loss of roosting habitat for this species. Indirect affects
may occur to this species as described in the analyses above. However, the avoidance,
minimization, and/or mitigation measures included in the MHCP Subregional Plan and City’s
Subarea Plan will reduce the indirect impacts to this species. The Preserve will be adaptively
managed, per the measures included in the MHCP Subregional Plan and City’s Subarea Plan
which will further reduce the indirect effects and benefit the species. After reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan and City’s Subarea Plan are not likely to jeopardize the continued existence or
recovery of this species.
Amount or Extent of Take
No take of California brown pelicans will occur as a result of the MHCP Subregional and City’s
Subarea Plans due to the conditions of coverage, no-net-loss of wetland, and conditions for
estuarine species policies within the MHCP and HMP.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) -
PZegudis chihi (White-faced ibis)
109
Status of the SDecies
Listing Status
The white-faced ibis is a California Department of Fish and Game special concern species with a
CNDDB rank of G5S 1. This species is not federally listed, however it is a Fish and Wildlife
Service migratory non-game bird of management concern.
Species Description
This species is a dark maroon to brown medium-sized wading bird with a long neck, long
decurved bill, and long legs (Ryder and Manry 1994). In breeding plumage the head, neck, upper
back, wing coverts, and undersides are chestnut-maroon with metallic green and bronze sheen,
while the wings take on purplish overtones (Ryder and Manry 1994). The white-faced ibis is
distinguished from the glossy ibis in breeding plumage by a red versus brown iris, red versus
blackish facial skin, all red versus grayish legs, and a border of white feathers which completely
separates their bill and eye from the rest of their dark head. The glossy ibis lacks these white
feathers (Kaufman 1990). The species was previously considered a subspecies (P. faZcineZZus
chihi) of the glossy ibis (P. faZcineZZusfuZcineZZus), but is now recognized as a full species (P.
chihi) (Ryder and Manry 1994). The white-faced ibis is considered to be conspecific with the
glossy ibis by some ornithologists, and the two species have produced hybrids in captivity (Ryder
and Manry 1994). In Louisiana, Alabama, and possibly eastern Texas, however, the two forms
nest in the same colonies, apparently without interbreeding (Ryder and Manry 1994).
Distribution
White-faced ibis breed locally in North America from Oregon eastward to North Dakota and
southward to the Mexican plateau. The largest breeding colonies usually are in Utah, Nevada,
Oregon, and coastal Texas and Louisiana (Ryder and Manry 1994). There are also breeding and
wintering populations in South America and Mexico, as far south as central Chile and central
Argentina, however, the details of the more southern distribution are less well known (American
Ornithologists’ Union 1983). The species winters from California (locally) eastward to Texas and
coastal Louisiana and southward to Guatemala (Ryder and Manry 1994).
The white-faced ibis is an uncommon summer resident in sections of southern California, a rare
visitor in the Central Valley, and is more widespread in migration. Formerly more common,
especially in the San Joaquin Valley, this species no longer breeds regularly anywhere in
California (Remsen 1978). A few pairs bred in 1977 and 1978 at the Salton Sea, and eight pairs
nested at Buena Vista Lagoon, San Diego County in 1979 (Garrett and Dunn 1981). The species
nested at Guajome Lake in Oceanside in 1901 (Sharp 1907) and in 1990 (John Martin, USFWS,
pers. obs.), and has nested there somewhat regularly since 1990 (P. Unitt, pers. comm.). White-
faced ibis have also nested repeatedly in the 1990s at Dulin Pond, east of Oceanside (P. Unitt,
pers. comm.). In the vicinity of the Salton Sea, it is fairly common April to September, and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 110 -
uncommon through the winter; it is an uncommon transient elsewhere in southern California, and
a very loial winter visitant along the coast (Garrett and Dunn 1981). Within southern California,
the species is most often recorded during migration and winter, with nesting occurring only rarely
in the coastal plain (Garrett and Dunn 1981).
Habitat Afinity
Migrant and wintering white-faced ibis may be found foraging in shallow lacustrine waters,
muddy ground of wet meadows, marshes, ponds, lakes, rivers, flooded fields, and estuaries. In
southern California, extensive marshes are required for nesting (Garrett and Dunn 198 1). The
species prefers shallow, grassy marshes and nests in dense, fresh emergent wetlands (Zeiner et al.
1990). In the southern San Jauquin Valley, hey and Severson (1984) found this species breeding
in flooded stands of saltcedar (Tarnarix spp.) and Baltic rush (Juncus balticus). Cogswell (1977)
noted that a variety of flooded agricultural fields are used for feeding in California.
Life History
The white-faced ibis is diurnally active throughout the year. Its diet is mainly composed of
aquatic and moist-soil insects, crustaceans and earthworms, amphibians, small fishes, and
miscellaneous invertebrates (Ryder and Manry 1994). It probes deep in the mud with its long bill,
and also feeds in shallow water or on the surface (Cogswell 1977). Ibises feed in large flocks of
over 1,000 individuals (Ryder and Manry 1994).
The species nests in dense, fresh emergent wetlands (Zeiner et al. 1990). The nest, which is made
of dead tules or cattails, is built amidst tall marsh plants, sometimes on mounds of vegetation.
According to Cogswell (1977), it rarely nests in trees, but it is not clear whether tree nesting has
been recorded in California. They are presumed to be monogamous (Ryder and Manry 1994).
Pairs will re-nest, if initial nesting attempt fails (Ryder and Manry 1994). Earliest recorded
breeding by a white-faced ibis was at two years of age (Ryder and Manry 1994). Nest components
are generally made-up of the dominant vegetation in the nesting area and varies between
populations (Ryder and Manry 1994). Usual clutch size is three to four, but may vary from two to
five (Ryder and Manry 1994). The eggs are incubated for 21 days, mostly by the female, and the
young are fed in or near the nest for about five weeks (Cogswell 1977). Fledglings first leave the
nest at six to seven weeks of ages (Ryder and Manry 1994). Normally, pairs will have one brood
per season (Ryder and Manry 1994). Nest success rates were measured at 63 percent for
populations in Utah (Ryder and Manry 1994). Number of seven to ten-day old chicks per clutch
average 1.42 to 2.99 (Ryder and Manry 1994).
Individuals are apparently loyal to both breeding and roosting sites but will wander widely
depending on water conditions and food availability (Ryder and Manry 1994). White-faced ibises
are not generally aggressive and do not exhibit territorial behavior until the nesting season (Ryder
and Manry 1994). Territories for nesting pairs comprise approximately one square meter around
the nest (Ryder and Manry 1994).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 111
Food may be stolen by California gulls (Lams californicus) and grackles, and ibises are
sometime's attacked by American coots (Fulica amen'cana) within coot territories (Ryder and
Manry 1994). Predation of eggs and nestling occurs by gulls, magpies, night-herons, gallinules,
owls, ravens as well as raccoons, skunks, coyotes and weasels (Ryder and Manry 1994).
Population Trend
White-faced ibis historically were far more common in all seasons throughout California (Grinnell
and Miller 1944), southern California specifically (Garrett and Dunn 198 1). Destruction of marsh
habitat, especially along the southern coast and in the San Joaquin Valley, is perhaps the main
factor responsible for the decline (Grinnell and Miller 1944, Remsen 1978). Following severe
drought, emergent wetland vegetation may take several years to recover to a condition suitable for
white-faced ibis nesting (Ryder and Manry 1994). Elsewhere in the range, pesticides had caused a
decline in numbers of the white-faced ibis (Terres 1980). The breeding range and populations
have expanded in the last two decades, owing in part to improved nesting habitat management in
Federal and State refuges, increased planting of alfalfa used by feeding ibises (in the western
U.S.), the banning of DDT and other pesticides in the 1970s, and improved breeding success at
major nesting centers (Ryder and Manry 1994). In California there have been modest increases in
the nesting population (Ryder and Manry 1994).
Threats
Diversion of natural water supplies away from existing wetlands to irrigation projects, especially
during severe droughts, has led to temporary or permanent abandonment of traditional colony sites
(Weller et al. 1958, Ryder et al. 1979, Henny and Herron 1989). The effects of wetland
destruction on ibis populations in Mexico are unknown but are cause for concern (Sharp 1985).
Humans entering active colonies may cause partial or total desertion, particularly during nest-
selection, nest-building, and incubation (Ryder and Manry 1994). Other threats to the white-faced
ibis include organochloride contaminants (e.g., DDT, DDE, DDD) (Ryder and Manry 1994)
which cause eggshell thinning and the accumulation of other toxicant such as mercury and
selenium in the breeding population, which have unknown effects on the population (Henny and
Herron 1989). Naturally occurring threats which may affect populations include botulism
outbreaks, extremely high temperatures and flooding (Ryder and Manry 1994).
Environmental Baseline
The white-faced ibis is an uncommon migrant and winter visitor to San Diego County (Unitt
1984). Within the MHCP planning area, white-faced ibis breeding colonies occur in Buena Vista
Lagoon and Guajome Lake which are both major populations and critical locations. They also
occur in Batiquitos, and San Elijo. lagoons where they are major populations. Location data is
limited, however, there is one occurrence in Solana Beach, Escondido and Encinitas and seven
occurrences in Oceanside within coastal salt marsh and freshwater marsh vegetation.
There are four occurrences in the City of Carlsbad and if the species continues its current breeding
range expansion, it may colonize appropriate nesting habitat in Carlsbad (e.g., Lake Calavera).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 112
The plan area contains 1,366 acres of non-riparian wetlands, including freshwater marsh, salt
marsh, an’d estuahe habitats. Additionally, the plan area supports approximately 1,812 acres of
agricultural fields. However, of this area, only the “panhandle” of Robertson Ranch lies within
the 100-year floodplain. Previously permitted actions will convert most of this agricultural area to
a detention basin and riparian forest; therefore, these potentially flooded agricultural fields will
not be available as foraging habitat for white-faced ibis.
Effects of the action
Direct Eflects
The MHCP does not include any species-specific conditions for coverage of the white-faced ibis.
However, implementation of Conditions for Estuarine species in Appendix E of the MHCP is
required for coverage of other wetland-dependent species, and these measures are expected to
benefit white-faced ibis by reducing potential for human disturbance (especially near important
potential breeding areas such as Buena Vista Lagoon), degradation of water quality, and invasion
by exotic species. Appendix E includes measures that must be implemented to ensure coverage of
species dependent on estuarine habitats. Measures include regulation of adjacent land use,
recreational access, mosquito control, noise, vehicle access, potential pollutants, access during
breeding season, camping and picnicking; area-specific management measures including fencing,
animal and plant pest control, habitat enhancement andor creation, trash removal, erosion control,
maintenance of tidal flushing; monitoring of covered species populations, biodiversity, habitat
area, effect of recreation on wildlife, pest animal and plant populations, use by migratory birds,
and success of restoration efforts; and development of public awareness program including public
participation in management, development of community outreach programs, and improvement of
trails and facilities to focus public access.
Not all of the location points are within the FPA. Only 50 percent are within the FPA in the City
of Encinitas and only 70 percent within the FPA in the City of Oceanside. However, 790 acres of
white-faced ibis suitable habitat will be conserved throughout the MHCP planning area.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of
estuarine and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of
estuarine habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777
acres of estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are
approximately 5.5 acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua
Hedionda Lagoon associated with the Interstate 5 right-of-way, which are not included in the
preserve since the City does not have ultimate control of these areas. The State Route 101 and
railroad rights-of-way across Buena Vista Lagoon are also not included in the preserve. There are
no projects proposed for this area, however, impacts may occur in the future in the right-of-ways
due to projects such as road widening which would be beyond the control of the City. Such
impacts would be analyzed and permitted under a different mechanism than the MHCP. 339 acres
of southern coastal salt marsh and freshwater marsh vegetation communities constitute potential
habitat for white-faced ibis. A small amount of additional habitat in the lagoons are also
technically not in the mapped area of the preserve, however, no projects are planned for this area
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 113
by the City and 100 percent conservation due to MHCP standards for avoidance, minimization,
and mitigation of wetland impacts assure no-net-loss of lagoon wetland habitat. However,
impacts can occur to such wetland communities as described in section 3.6 of MHCP Volume 1.
Since such impacts would need to be fully mitigated according to section 4.4.2 of MHCP Volume
1, no-net-loss of function or value will occur in MHCP, although there could be a temporal loss of
such functions and values. The MHCP conditions for estuarine species and fact that all the
lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due to these
standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine, salt
marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, direct take of animal
species is expected to be minimized because any areas proposed for disturbance would be avoided
where MHCP species or nests are known or found to be present.
Indirect Effects
Indirect impacts have the potential to cause adverse effects to white-faced ibis. These indirect
impacts include night lighting, human disturbance, depredation by domestic pets, and habitat
degradation, as generally explained and applicable in the “General Indirect Effects” section.
White-faced ibis may be impacted by human disturbance near breeding and foraging areas.
Specifically, indirect impacts to the white-faced ibis could result from increases in human use of
lagoons. For example, conversion of agricultural areas to urban uses at the proposed Hub Park at
the southeast corner of Agua Hedionda Lagoon and the farmland at the northeast corner of
Batiquitos Lagoon. Buffer zones of at least 100 feet between development and wetland habitat
within the coastal zone are likely to reduce such impacts.
Urban run-off may also increase as a result of implementing the MHCP Subregional Plan. In
addition to increased peak flows, increase in impervious surfaces associated with urbanization can
result in: 1) stream bed scouring and habitat degradation; 2) shoreline erosion and stream bank
widening; 3) loss of aquatic species; 4) decreased baseflow (USEPA 1999). Run-off may pose
numerous threats to the environment as discussed in the “General Indirect Effects” section.
Specific to white-faced ibis, habitat degradation, impacts to water resources and changes in prey
availability may have indirect impacts to the species. Alterations to the hydraulic regime of salt
marshes and degradation of water quality (dredging, non-point source run-off) may result in
conversion of salt marsh habitat by allowing fresh water-tolerant plant species such as cattails to
displace salt marsh species. Such type conversion may result in an increase in potential white-
faced ibis nesting habitat. However, because white-faced ibis require relatively large expanses of
tall freshwater marsh vegetation to nest, significant increases in amount of ibis nesting habitat are
unlikely. Water quality may also affect prey abundance, diversity, and distribution. Contaminants
that may affect aquatic organisms in the lagoons may be carried to the lagoon by storm water
runoff from throughout the watershed. Developed areas are sources of non-point source pollution.
Development also increases the amount of impervious surface in the watershed, increasing the
velocity and volume of storm water runoff, thus exacerbating conveyance of non-point source
pollution in storm water runoff. Therefore, development throughout the MHCP planning area
may affect white-faced ibis and their lagoon habitat.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 114
The plan entails retention of connectivity between large habitat patches, intended to allow
predators’such as coyotes and bobcats to access to most areas of wildlife habitat throughout the
MHCP planning area. White-faced ibis may benefit from presence of larger predators, as they
reduce potential for overpopulation of smaller predators that may prey on ibis nests (Crooks and
Soule 1999).
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will directly and indirectly
affect this species through habitat loss. However, a majority (78 percent) of the white-faced ibis
species points are within the FPA and it should also be protected by the conditions for estuarine
species, critical locations, and no-net-loss of wetland policies in the MHCP. In addition, this is a
wide ranging species with only a small percentage of the species range within the MHCP and the
City of Carlsbad. The MHCP Subregional Plan and City’s Subarea Plan will provide monitoring
and management of this species that will detect and minimize negative impacts that are affecting
white-faced ibis. Additionally, this species should benefit from the connected preserve system
that will be managed and monitored in the City and throughout the MHCP in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan,
which will further reduce the indirect effects and benefit the species. After reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan and the City’s Subarea Plan are not likely to jeopardize the continued existence
or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetennined number of individual white-faced ibis associated
with temporal loss of southern coastal salt marsh and freshwater marsh habitat will be taken in the
form of harm as a result of the City’s subarea plan. However, the number is expected to be small
because of the MHCP and City’s no-net-loss of wetland policy, the MHCP condition of coverage,
and the MHCP conditions for estuarine species. Thus, the City’s subarea plan will not jeopardize
the continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 115
Accipiter cooperii (Cooper’s hawk)
Status of the Suecies
Listing Status
The Cooper’s hawk is a California Department of Fish and Game special concern species with a
CNDDB rank of G4S3. There is no federal listing for this species.
Description
Accipiter cooperii is a medium-sized hawk with short, rounded wings and a long, rounded tail.
Their legs are yellow, iris yellow in younger birds, and orange or red in older birds (Rosenfield et
al. 1992a). The sexes are similar in plumage, but males are generally more brightly colored than
females (Rosenfield and Bielefeldt 1993). Their back and upper wing coverts are brown to blue-
gray in adults, and medium brown with some white mottling and rufous feather edging in
juveniles (Rosenfield and Bielefeldt 1993).
A. cooperi, A. gundlachi, and A. bicolor comprise a superspecies (Brown and Amadon 1968,
Stresemann and Amadon 1979), apparently evolved from a common stock of tropical American
accipiters (Wattel 1973). Despite significant size differences, eastern (A. e. cooperii) and western
(A. c. mexicanus; Friedmann 1950) subspecies are no longer recognized.
Distribution
Cooper’s hawks breed from British Columbia eastward to Nova Scotia and southward to northern
Mexico and Florida (American Ornithologists’ Union 1983). In California, the Cooper’s hawk is
a breeding resident throughout most of the wooded portion of the state. It breeds in the southern
Sierra Nevada foothills, New York Mountains, Owens Valley, and throughout other scattered
areas in southern California. Its breeding range is from sea level to above 2,700 meters. Cooper’s
hawks are present year-round nearly throughout California, except along the Colorado River and
in desert areas, where the species no longer breeds (Garrett and Dunn 1981). Although the
Cooper’s hawk breeds in southern California and has a year-round resident population, it also
occurs in the region as a spring and fall migrant and as a winter resident (Garrett and Dunn 1981).
Ha bitat Afinity
The Cooper’s hawk breeds primarily in riparian areas and oak woodlands and is most common in
montane canyons (Garrett and Dunn 1981). It frequents landscapes where wooded areas occur in
patches and groves and often uses patchy woodlands and edges with snags for perching and dense
stands with moderate crown-depths for nesting (Zeiner et al. 1990). The Cooper’s hawk tends to
nest in forest patches with lower densities of taller and larger trees and a greater proportion of
hardwood cover than conifer (Trexel e? al. 1999). Migrant and wintering birds are generally less
selective in their choice of habitats and may be found with regularity in developed (e.g., suburban)
areas, however, Zeiner et al. (1990) noted that this species is seldom found in areas without dense
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 116 -
tree cover or patchy woodland habitat. Nests are generally located on a horizontal limb of a pine
or hardwbod, near the trunk or in the crotch of a hardwood tree species, usually 3 to 18 meters
above the ground and occasionally in the old nest of a crow (Harrison 1978). Within California,
Cooper’s hawks use dense stands of live oak, riparian deciduous, or other forest habitats near
water most frequently (Zeiner et al. 1990), although they may also be found in eucalyptus
woodlands (Dudek and Associates 2000b). Cooper’s hawks may forage in a wide variety of
habitats in Carlsbad, including riparian woodland, chaparral, coastal sage scrub, annual grassland,
marsh, eucalyptus woodland, and vegetated suburban areas. This species is known to nest in
urban environments in areas with mature trees (Boal and Mannan 1999, Stahlecker and Beach
1979, John Martin USFWS pers. obs.), sometimes at higher densities than in exurban areas
(Rosenfield et al 1995, Boal and Mannan 1998).
Life History
The Cooper’s hawk is diurnally active throughout the year (Zeiner et al. 1990). During breeding
and non-breeding, the species predominantly uses avian prey, sometimes taking fish, small
mammals, reptiles and amphibians (Terres 1980). In comparison to the northern goshawk, the
Cooper’s hawk takes more avian prey (Bosakowski et al. 1992). The cooper’s hawk hunts in
broken woodland and habitat edges, catching prey in the air, on the ground, and in vegetation.
They use cover to hide, attack, and approach prey but will also soar and make low, gliding search
flights (Zeiner et al. 1990). It forages by dashing through the woods in a low, swift flight, around
trees, through the brush and reaches out in the air or on the ground to catch avian prey with their
talons (Terres 1980). After catching its prey, the Cooper’s hawk may fly with the prey to a water
source in order to drown it (Terres 1980).
Both sexes are usually present on the nest area by mid-to late March (Meng 195 1, Rosenfield
1991a). In California, the first eggs are generally laid in April (Asay 1987). Pairs will often
renest if the initial clutch is lost in early incubation or before (Rosenfield and Bielefeldt 1993).
Clutch size ranges from 1 to 7 and is usually 3 to 5 (Rosenfield and Bielefeldt 1993). Eggs are
incubated mostly by the female for approximately 24 days (Terres 1980). Females care for and
feed the young until they are able to dismember prey on their own (approximately 18-21 days)
(Meng 1951). In western Cooper’s hawks fledglings depart the nest at 27 to 30 days, but will
return to the nest for prey deliveries and roosting for at least 10 days (Reynolds and Wight 1978).
Age of first breeding is generally 2 years or older (Rosenfield and Bielefeldt 1993).
Mortality rates have been estimated as 72 percent to 78 percent in the first year, and 34 percent to
37 percent thereafter (Rosenfield and Bielefeldt 1993). The maximum reported age for a
Cooper’s hawk is 12 years (Rosenfield and Bielefeldt 1993). Eggs may be depredated by
raccoons and rarely by American crow (Rosenfield and Bielefeldt 1993). Adults may be
depredated by great homed owl (Bubo virginianus), red-tailed hawk, and northern goshawk
(Rosenfield and Bielefeldt 1993). The species may compete, to a limited extent, with sharp-
shinned hawks and northern goshawks. Although the northern goshawk is a potential competitor,
niche overlap is reduced by using different habitats and by using different species of prey,
different sizes of prey and by foraging in different zones (Bosakowslu et al. 1992). The Cooper’s
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 117 -
hawk is more of a generalist, having a greater niche width than both sharp-shinned hawks and
goshawks’.
Population Trend
This species was once considered a common nester throughout California and was described as
“varyingly common, to even abundant (for a hawk) in autumn in favorable territory” (Grinnell and
Miller 1944). Southern California’s breeding population reportedly has been “much reduced in
recent decades, especially in lowland areas where much riparian woodland has been destroyed”
(Garrett and Dunn 1981). A serious decline occurred in the 1970s during the nesting season
probably due to eggshell thinning resulting from pesticides (Terres 1980). Counts of migrant
Cooper’s hawks in western mountains suggest a stable or increasing trend between 1977-2001,
with evidence of a decline after 1998, possibly related to drought (Hoffman and Smith 2003).
Only about 40 pairs were detected in Orange County during recent breeding bird atlas survey
efforts there (Gallagher 1996).
Threats
Habitat destruction, mainly in lowland riparian areas, due to urbanization and development is
expected to be the main threat, although direct or indirect human disturbance at nest sites and the
use of organochloride pesticides can also be detrimental (Remsen 1978, Rosenfield and Bielefeldt
1993, Boal and Mannan 1998). Contaminants other than organochloride pesticides (e.g., dieldrin,
PCB’s, mercury, and other heavy metals) have also been found in eggs, but with unknown effects
(Snyder et al. 1973, Pattee et al. 1985). A few recent cases of organophosphate poisoning have
been reported (Rosenfield et al. 1991b) but the effects on population is unclear, as are the
consequences of pesticide use in Mexico for birds wintering there (Reynolds 1989). Collisions
with cars have been documented, but the magnitude of this threat is unclear (Keran 1981). Boal
and Mannan (1999) found that the greatest cause of adult mortality among urban Cooper’s hawks
was collisions, primarily with windows. Trichomoniasis caused the death of approximately 40
percent of nestling Cooper’s hawks in Tucson (Boal and Mannan 1999). The high nestling
mortality rate they observed is likely associated with the prevalence of columbids - which show a
high rate of Trichomonas infection -- in the diet of Cooper’s hawks in Tucson. West Nile Virus
also threatens this species.
Environmental Baseline
There are location points for Cooper’s hawk in all of the MHCP cities except Solana Beach.
Potential breeding areas in the MHCP planning area include the San Luis Rey River, Pilgrim
Creek, and oak woodland habitats in San Marcos and Escondido. There are no major populations
in the MHCP, but the San Luis Rey River, Pilgrim Creek, and oak woodland habitats in San
Marcos and Escondido are considered critical locations. There are 1,807 acres of suitable
(riparian forest, riparian woodlands, oak woodlands) Cooper’s hawk habitat in the MHCP
planning area. Habitats other than riparian and oak woodland are used as foraging areas by this
species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 118 -
Cooper’s hawks have been documented within the Subarea, in a variety of habitats, including oak
woodland and riparian areas. This species is not expected to have a high density in the Subarea
due to the scarcity of primary habitat constituents. Baseline information is lacking for the
Cooper’s hawk and it is not readily surveyed in the area. An influx of migrant birds increases
numbers during the non-breeding season. The Carlsbad-Oceanside-Vista Annual Christmas Bird
Count (which includes all of the coastal areas of the Carlsbad Subarea, plus other areas outside of
the Subarea), yielded 11 Cooper’s hawk (National Audubon Society 2002). Since 1970 there has
been an average of 11 documented per year in this count. Based on high densities of Cooper’s
hawks observed in urban areas by Boa1 and Mannan (1998) and Rosenfield et al. (1995), and the
amount and distribution of suitable nesting habitat (riparian woodland, riparian forest, oak
woodland, and eucalyptus woodland) in Carlsbad, we estimate the HMP area could support 5-10
nesting pairs.
Effects of the Action
Direct Effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1.
’
As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, qualified biologists must survey all potential nesting areas during the nesting
season. Surveys shall be conducted when impacts could occur as a result of direct or
indirect impacts by placement of a project in or adjacent to suitable habitat. Preserve areas
must include 300-foot biological buffers around nest sites where feasible.
Avoid tree pruning activities in or near reserve areas during the breeding season (March 1
through July 3 I).
2.
Direct impacts to Cooper’s hawk are not expected from the MHCP Subregional Plan or the City’s
Subarea Plan due to breeding season restrictions and oak tree removal restrictions. However,
direct impacts will occur to suitable Cooper’s hawk nesting and foraging habitat throughout the
MHCP planning area.
The riparian woodlands will be conserved at 100 percent through the avoidance, minimization,
and mitigation of wetland impacts standards to ensure no-net-loss of wetlands. However, impacts
can occur to such wetland communities as described in section 3.6 of MHCP Volume 1. Since
such impacts would need to be fully mitigated according to section 4.4.2 of MHCP Volume 1, no-
net-loss of function or value will occur in MHCP, although there could be a temporal loss of such
functions and values. The MHCP will conserve 79 percent of oak woodlands throughout the
planning area. Overall, approximately 1,626 acres (90 percent) of suitable habitat is expected to
be conserved, including approximately 8 1 percent of critical areas in Escondido and San Marcos.
The FPA includes 34 of 57 point localities (60 percent) with many of the point localities outside
of the FPA representing observations of Cooper’s hawks flying over developed areas between
suitable habitats. The MHCP will also directly impact foraging habitat throughout the planning
area, however, 5,334 acres (62 percent) of coastal sage scrub and 1,687 acres (32 percent) of
grassland will be conserved in the planning area.
.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 119 -
The Subarea would allow impact to Cooper’s hawks’ primary nesting habitats through temporal
loss of up to 2 acres of oak woodland. The loss is considered temporal due to the City’s no-net-
loss of oak woodland policy. The City will also conserve 100 percent of riparian due to the
wetland standards for avoidance, minimization, and mitigation of wetland impacts to assure no-
net-loss of wetlands. However, impacts can occur to such wetland communities as described in
section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated according
to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP,
although there could be a temporal loss of such functions and values. The City requires the
following additional conservation condition to help minimize impacts to this species: In Proposed
Hardline Areas and Standards Areas with oak woodlands or oak riparian forest, surveys shall be
conducted for nesting Cooper’s Hawks. If the species is present, no direct impacts to oak
woodland or oak riparian forest shall be allowed in the nesting season, and a 300 ft. impact
avoidance area around active nest sites shall be maintained. The long-term preserve management
plan shall provide area-specific management directives for oak woodlands and oak riparian forest,
including specific adaptive management measures to protect against detrimental edge effects from
adjacent development, recreational impacts, and other direct and indirect impacts.
Because of the high degree of conservation of nesting habitat, the assurance of buffer zones
around active nest sites, and the avoidance of tree pruning in preserves during the breeding
season, we anticipate few direct impacts to this species.
Indirect Efsects
Indirect impacts have the potential to adversely affect Cooper’s hawks within the Subarea. These
indirect impacts include habitat fragmentation, edge effects including increased human
disturbance, noise effects, disruption of the natural fire regime, changes in hydrology from
adjacent development, increased lighting, and the proliferation of exotic species, as generally
explained and applicable in the “General Indirect Effects” section. General indirect effects may
affect Cooper’s hawks or abundance and diversity of their prey. Cooper’s hawks may be
indirectly impacted by the degradation of riparian habitat by nuisance exotic species, decreases in
water quality, and edge effects produced by development. However, a majority of the areas with
Cooper’s hawk locality points will be managed by the City initially. All preserve areas will be
managed once funding, such as a regional funding source, is available.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this
species through habitat loss. No direct impacts are expected from the MHCP Subregional Plan or
City’s Subarea Plan due to breeding season conditions and oak removal restrictions. This species
will benefit from the no-net-loss of wetlands and critical locations policies and 90 percent of the
Cooper’s hawk suitable nesting habitat will be conserved. The MHCP Subregional Plan and
City’s Subarea Plan will provide monitoring and management of this species that will detect and
minimize negative impacts that are affecting Cooper’s hawk. Additionally, this species will
benefit from a foraging aspect by the connected preserve system that will be managed and
monitored in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively
Carlsbad Subarea Plan Biological and Conference Opinions 0;WS-SDG-847.4) 120 -
managed, per the measures included in the MHCP Subregional Plan, which will further reduce the
indirect e‘ffects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional and the City’s Subarea
Plans are not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual Cooper’s hawks will be taken
in the form of harm through habitat loss as a result of the City’s subarea plan within a maximum
of 5 acres of riparian forest, riparian woodlands, and all oak woodland habitat. This number is
expected to be low (not more than 8 individuals) because 96 percent of their habitat will be
conserved, and the species will benefit from the no-net-loss of wetland and wetland buffer
policies. The incidental take is expected to be in the form of harm and harassment. This level of
anticipated take is not likely to jeopardize the continued existence or recovery of this species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 121
Pandion haliaetus (Osprey)
Listing Status
The osprey is not a federally listed species. However, it is considered a species of special concern
by the California Department of Fish and Game.
Species Description
The osprey is a large raptor, weighing approximately 1.2- 1.5 kilograms, approximately 0.5 meters
in total length, with a wingspan of approximately 1.4-1.8 meters. Its underparts, from chin to
undertail coverts, are white, often interrupted by a broken “necklace” of dark streaks on the breast.
Upperparts, including the wings and back, are primarily dark chocolate-brown from the hindneck
to the uppertail coverts. The tail is dark brown with narrow transverse gray bands. Ospreys have
a white crown and forehead, and a dark brown line through the eyes (Poole, et.al2002). The
powerful legs and feet are light greenish-gray, and have large talons that are rounded in cross-
section. The eye is yellowish and the hooked raptorial bill is dark horn-colored. In flight the
wings are characteristically held bent at the carpal joint, and a large dark carpal patch is evident.
Sexes are difficult to distinguish. Juvenile osprey are distinguished from adults by conspicuous
buff edges on the dark brown contour feathers, including the back and wing coverts, of juveniles.
Distribution
The osprey is found on every continent except Antarctica (Terres, 1980). In North America,
ospreys breed from northwest Alaska and Canada south to Baja California, Mexico, and Florida
(Johnsgard, 1990). In the U.S., it occurs close to coastal waters on the east and west coasts and
inhabits inland areas around the Great Lakes, Utah, Arizona, and Nevada. Ospreys winter on the Gulf
Coast and Southern California south into Central and South America (Terres, 1980). This species
breeds throughout Northern California from the Cascade Range south to Marin County and throughout
the Sierra Nevada (Zeiner et al., 1990).
Ospreys are a widely distributed species in North America, but are an uncommon wintering species
and are relatively rare during the breedmg season in San Diego County. Ospreys have been recorded at
Agua Hedionda Lagoon, Lake Hodges, San Vicente Reservoir, and San Diego Bay (T. Oberbauer
personal communication). A single (P. Unitt personal communication) or pair (M. Klein personal
communication.) of ospreys have recently been sighted using Dixon Reservoir in Escondido, and P.
Unitt (personal communication.) expects ospreys may nest at Lake Wohlford in the near future.
Osprey nested in Mission Bay, and along the San Diego River near Mission Gorge Road in 2002. At
least one individual and as many as three are regularly seen year-round at and near the San Diego River
Flood Control Channel. (John Martin, USFWS, pers. obs.).
Habitat Aflnity
Ospreys are found only in association with lakes, coastal estuaries, reservoirs, or large rivers, though
they are known to forage occasionally in near-shore Ocean waters. Ospreys nest near these habitats in
Carlsbad Subarea PIan Biological and Conference Opinions (FWS-SDG-847.4) 122 -
large dead-topped trees, snags, cliffs, and man-made structures that can support their large stick
nests. D&ng thk breeding season, ospreys generally restrict their movements to activities in and
around the nest site, and between the nest and foraging sites.
- Life History
Ospreys feed almost exclusively on fish, primarily surface-schooling species or those in shallow water,
although some mammals, birds, reptiles, and amphibians are also eaten. Ospreys require open, clear
water for foraging. They characteristically glide or hover high over the surface, then plunge feet-first
into the water, up to a meter below the surface. Coastal foraging includes use of Ocean waters, salt
water marshes, lagoons and ponds, estuaries and silted river mouths.
Nest selection may include trees, cliffs, large shoreline boulders and on the ground in predator-he
islands. Sticks, grass and algae are used for nest construction, which may continue through the nesting
period and hatching. The clutch consists of 3-4 eggs with a 32 to 43 day incubation period. There is
one brood per year with fledgmg occurring within 48 to 59 days.
The osprey’s fall migration extends from mid July to early November and Spring from late February to
May (Poole, et.al2002). During these periods migrants may pass through San Diego County, the
MHCP area, and Carlsbad.
Population Trend
Ospreys sharply declined in abundance in the 1950s and 1960s, when use of DDT was prevalent
(Terres, 1980). There were an estimated 8,000 pairs in the contiguous U.S. in the early 1980s with
Florida having the largest numbers, followed by Chesapeake Bay and Maine (Johnsgard, 1990). Based
on Christmas Bird Count data, the US. winter population was estimated at 7,080 indwiduals in 1986,
with over half in Florida. The North American breeding population has been estimated at 17,000 to
20,000 individuals (Poole, 1989). Since DDT was banned in the U.S. in 1972, osprey populations
have increased considerably in many parts of the country (Kaufman, 1996). Counts of migrating
osprey at several locations in the western United States (Hoffman and Smith 2003), Christmas Bird
Count data (National Audubon Society 2002), and Breeding Bird Survey data (Sauer et al. 2002) all
indicate a significant increase in osprey populations in the western United States over approximately
the past 20 years.
Threats
Ospreys are vulnerable to human disturbance at their nest sites and adverse impacts to potential
foraging habitat. The historic decline in osprey numbers is largely attributed to the adverse effects of
DDT and other pesticides on reproduction (Johnsgard, 1990). Bioaccumulation of DDT in tissues of
raptorial birds causes thinning of eggshells, resulting in reproductive failure. Some areas still have
greatly reduced osprey populations that may be due to residual effects of these now banned pesticides.
Over half of the North American population may winter in Latin America and the West Indies, where
pesticide use is not as strictly regulated as in the U.S. and Canada. These birds may continue to be
exposed to levels of pesticides sufficient to inhibit successful reproduction
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 123
Environmental Baseline
Within the MHCP planning area, ospreys have been recorded in Carlsbad, Encinitas, Escondido, and
Oceanside at Agua Hedionda Lagoon, Buena Vista Lagoon, Batiquitos Lagoon, San Elijo Lagoon, the
San Luis Rey River, and Lake Hodges. Ospreys have recently been sighted usingDixon Reservoir in
Escondido which may nest at Lake Wohlford. There re no major populations of ospreys in MHCP, but
all the coastal lagoons and estuaries are considered critical foraging areas.
Osprey remain today an uncommon fall and winter visitor and rare in the spring and summer (Unitt
1984). This species is frequently observed at Aqua Hedionda and Batiquitos Lagoons, however there
have been no observations of nesting in the area. Species-specific survey data for the MHCP plan area
is generally not available for this species. The Carlsbad-Oceanside-Vista Annual Christmas Bird
Count (which includes all of the coastal areas of the Carlsbad Subarea, plus other areas outside of the
Subarea), yielded 8 osprey in 2002 (National Audubon Society 2002). Since 1974 there has been an
average of 4 documented per year during this count. Osprey occur regularly in the HMP area at San
Elijo and Batiquitos Lagoons (John Martin, USFWS, pers. obs.). Information regarding this species is
otherwise lacking and population numbers are not available due to sporadic and low survey effort. Of
eight documented observations of this species within the Subarea, all but one (near Escondido Creek)
are associated with lagoons or the San Luis Rey River. The majority of land surrounding the osprey’s
preferred habitat has been developed, while maintenance projects are still active within the lagoons
themselves.
The lagoon systems and coastal habitat in the Subarea play an important role in the foraging behavior
of this species. Agua Hedionda Lagoon was initially dredged in 1954 to provide a source of cooling
water for San Diego Gas & Electric Company’s Encina Power Plant. Since 1954, the outer lagoon has
undergone periodic maintenance dredging, while no dredgng had occurred in the middle and inner
lagoons. The outer lagoon is dredged every one to three years. In 1998 SDG&E was permitted to
dredge Agua Hedionda’s middle and inner lagoons and discharge the dredged material (spoil) on the
Encina Power Plant jetty and a borrow pit created in the lagoon. The resultant changes in water depth
may have affected availability of prey for osprey.
Also, Batiquitos Lagoon has experienced extensive restoration, including dredging. Restoration of this
seasonal tidal waterbody was initiated in 1994 and completed in 1996. It resulted in the continuous
tidal exchange of Pacific Ocean waters. Dredge spoils were used as beach nourishment north of the
lagoon. The inlet channel to Batiquitos Lagoon was also dredged in 2000.
Buena Vista, Agua Hedionda, and Batiquitos lagoons contain approximately 934 acres of estuarine and
salt marsh habitat that support or potentially support the osprey. All suitable osprey foraging habitat in
the HMP area (open water in Batiquitos, Agua Hedonda, and Buena Vista lagoons, and Lake
Calavera) is included within the preserve.
Carlsbad Subarea Plan Biological and Conference Opinions WS-SDG-847.4) - 124
Effects of the Action
Direct Egects
The MHCP Subregional Plan has no conditions of coverage for this species. However, all 1,399 acres
of the potential foraging habitat and 90 percent of the known location points in the study area will be
conserved. In addition, Appendix E (Conditions for estuarine species) of the MHCP includes
measures that must be implemented to ensure coverage of species dependent on estuarine habitats.
Due to the no-net-loss of wetland policy, maximum conservation of the lagoon and marsh ecological
communities, and it is possible that most suitable nesting areas will be within the 100 foot buffer zone
of lakes, lagoons, estuaries, and riparian areas that will be conserved, minimal direct impacts to
ospreys are expected from the MHCP Subregional Plan. However, there is the potential that loss of
vertical structure surrounding the lagoons could occur that would adversely affect the osprey. This
could include the removal of eucalyptus trees adjacent to the lagoons.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve. There are no projects proposed for this area,
however, impacts may occur in the future in the right-of-ways due to projects such as road widening
which would be beyond the control of the City. Such impacts would be analyzed and permitted under
a different mechanism than the MHCP. A small amount of additional habitat in the lagoons are also
technically not in the mapped area of the preseke, however, no projects are planned for this area by the
City and 100 percent conservation due to MHCP standards for avoidance, minimization, and
mitigation of wetland impacts assure no-net-loss of lagoon wetland habitat. However, impacts can
occur to such wetland communities as described in section 3.6 of MHCP Volume 1. Since such
impacts would need to be fully mitigated according to section 4.4.2 of MHCP Volume 1, no-net-loss
of function or value will occur in MHCP, although there could be a temporal loss of such functions
and values. The MHCP conditions for estuarine species and fact that all the lagoons are in the coastal
zone, also provide more protection to the lagoon areas. Due to these standards, any losses would only
be temporal and no net decrease in lagoon habitat (estuarine, salt marsh, etc.) would occur as a result of
the City's Subarea Plan. In addition, direct take of animal species is expected to be minimized because
any areas proposed for disturbance would be avoided where MHCP species or nests are known or
found to be present.
The open water in Batiquitos, Agua Hedionda, and Buena Vista lagoons, and Lake Calavera includes
all suitable osprey foraging habitat in the HMP. Therefore, we anticipate no direct impacts to osprey
as a result of the Subarea plan. Suitable nest substrates are not mapped, and are difficult to quantify.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 125 -
However, because osprey characteristically locate nests close to suitable foraging habitat, suitable nest
substrates’are likely to be conserved in wetland buffer zones.
Zndirect Efects
Indirect impacts have the potential to cause significant adverse affects to osprey. These indirect
impacts include night lighting, human disturbance, depredation by domestic pets, and habitat
degradation, as generally explained and applicable in the “General Indirect Effects” section.
Indirect impacts to the osprey could result from the degradation of water quality, and subsequent
effects to prey populations in coastal lagoon systems. Contaminants that may affect aquatic organisms
in the lagoons may be carried to the lagoon by storm water runoff from throughout the watershed.
Developed areas are sources of non-point source pollution. Development also increases the amount of
impervious surface in the watershed, increasing the velocity and volume of storm water runoff, thus
exacerbating conveyance of non-point source pollution in storm water runoff. Therefore, development
throughout may affect osprey and their lagoon habitat. Turbidity plumes, generated by the runoff of
silt and fines into the lagoons or Pacific Ocean from upstream erosion caused by development, may
obscure available forage fish in the lagoons that potentially could be preyed upon by osprey. This issue
of water clarity is significant given that the osprey is a sight feeder
Indirect effects may also occur from loss of roosting sites from adjacent habitat development, and
increases in human disturbances at lagoon areas. Specifically, indirect impacts to the osprey could
result from conversion of agricultural areas to urban uses at the proposed Hub Park at the southeast
comer of Agua Hedionda Lagoon and the farmland at the northeast comer of Batiquitos Lagoon.
However, the following specific management measures will be implemented to minimize impacts to
this species (see Table 9 of the City’s Subarea Plan):
1. Manage preserve areas to maintain lagoon hydrology and water quality and restrict activities
that would disturb nesting. Consider provision of nesting platforms adjacent to foraging areas
as part of detailed management plan.
The long-term preserve management plan shall provide area-specific management directives
for foraging areas at Agua Hedionda, Batiquitos and Buena Vista Lagoons and upstream
freshwater marsh habitats, including specific adaptive management measures to address water
quality and protect against detrimental edge effects from adjacent development, recreational
impacts, and other direct and indirect impacts.
2.
These measures along with those in Appendix E of the MHCP will be implemented, to minimize
indirect impacts to osprey and other estuarine species. Management is expected to occur initially via
lagoon management by California Department of Fish and Game.
Conclusion
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 126 -
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this species
as described above. No direct impacts to individuals or nests are expected from the MHCP
Subregional Plan or City’s Subarea Plan due to 100 percent conservation at the coastal lagoons and
estuaries. In addition, this species will benefit from the no-net-loss of wetlands, wetland buffer and
critical locations policies and 90 percent of the known location points will be conserved. The MHCP
Subregional Plan and City’s Subarea Plan will provide monitoring and management of this species that
will detect and minimize negative impacts that are affecting ospreys. Additionally, this species will
benefit from a foraging aspect by the connected preserve system that will be managed and monitored
in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. However, there could be a loss of vertical structure surrounding the lagoons which
the ospreys rely upon. Such impacts are not currently identified to occur, but have the potential within
the life of the permit. After reviewing the current status of this species, the environmental baseline for
the action area, the effects of the proposed action, and the cumulative effects, it is the Service’s
biological opinion that the MHCP Subregional and the City’s Subarea Plans are not likely to
jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that no more than one Osprey will be taken in the form of harm as a result of
the City’s subarea plan. Take would be in the form of harm from habitat loss of vertical structure
adjacent to the lagoons. The take is limited to one individual because 100 percent of all suitable
habitat will be conserved and the one known point location will be conserved. In addition, this
species will benefit from the no-net-loss of wetland and wetland buffer policies.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 127
Falco peregrinus anaturn (American peregrine falcon)
Status of the Species
Listing Status
The American peregrine falcon (peregrine falcon) was federally listed as endangered in 1970 (35 FR
16047). It was also listed as endangered in the state of California on June 27, 1971. Critical habitat
was not designated for this species. A Pacific Coast Recovery Plan for the American peregrine falcon
was adopted in 1982. This plan recornmended that delisting be considered when 185 wild, self-
sustaining pairs are established within the recovery unit, with at least 120 pairs in California, and
fledging success averages 1.5 young per pair for a five-year period. In June 1995, the Service
published an advance notice of a proposal to remove the American peregrine falcon from the list of
endangered and threatened wildlife (60 FR 34405-34409). Continuing population increases and the
magnitude of continuing recovery efforts by a variety of agencies, organizations, and the interested
public prompted the Service to propose the delisting of the species in 1998 (Brown 1999). The final
rule to remove the American peregrine falcon from the Federal list of endangered and threatened
wildlife was published August 25, 1999 (64 FlX 46542). The species is still listed as endangered, and
is considered a fully protected species, by the State of California.
Species Description
F. peregrinus are moderately large falcons, with males approximately crow-sized. The females are
significantly larger than males: up to 21 inches long-with a wingspan of about 40 inches. Adult F.
peregrinus have slate-gray wings and backs. Underparts are pale buff from chin to undertail coverts.
Sides of the breast, sides, flanks, femoral feathers, and undertail coverts are barred with blackish. On
the central breast, the bars are replaced by spots. Upper breast may be unspotted. Coloration of the
head is variable, but characteristically shows a blackish “hood”, with a broad, rounded blackish area
extending downward from the cheek. The crown and hindneck are usually blackish, with a variable
light buff area on the side of the neck. The bill is short, hooked, neutral gray basally, darker gray
distally, with a prominent tomial tooth. The eye is large and dark brown. Bare parts (cere, supraorbital
ridge, legs and feet) are yellow. Legs and feet are large and strong, with sharp, hooked, black talons.
Wings are long and pointed, but relatively broad-based. The tail is broad, of medium length, and
somewhat rounded. Immature falcons are buff-colored with brown streaks on the underparts, with
dark brown backs (U.S. Fish and Wildlife Service 1999). Bare parts of immature birds are greenish-
gray. There are three subspecies of Falco peregrinus in North America: the American (F. p. anaturn),
Arctic (F. p. tundrius), and Pede’s (8‘. p. pealei).
Distribution
The peregrine falcon has a worldwide distribution that is more extensive than any other bird. The
species breeds in North America from Alaska, east to Labrador, southward to southern California and
Baja California, central Arizona and Mexico. The species winters from southern Alaska to Tierra del
Fuego in southernmost South America (American Ornithologists’ Union 1983). In California, the
species breeds and winters throughout the state, with the exception of desert areas (Zeiner et al. 1990).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 128
The peregnne is a very uncommon breeding resident and uncommon as a migrant or as winter
resident. Active nesting sites of this species within California are known from along the coast north of
Santa Barbara, in the Sierra Nevada Mountains, and other mountains of northern California. Several
nest sites are known for San Diego County, including the Coronado Bridge (PaveIka 1990), a large
crane on the shore of south San Diego Bay, the Grant Hotel in downtown San Diego, and sea cliffs on
the southern tip of Point Loma. Some of the individuals that breed farther north migrate into California
for the winter months. During this time, peregrines can be seen inland throughout the Central Valley
and occasionally on the Channel Islands. Spring and fall migrants occur along the coast and in the
western Sierra Nevada Mountains (Brown 1999). As a transient species, peregrines may occur almost
anywhere within appropriate habitat (Garrett and Dunn 1981). This species is not known to breed
within the Subarea. However it winters regularly at Batiquitos and Aqua Hedionda lagoons, and has
been observed repeatedly over large agricultural areas in eastern Carlsbad (John Martin, USFWS, pers.
obs.).
Habitat Afinity
Peregrine falcons are found in a large variety of open habitats, including tundra, marshes, seacoasts,
savannahs and high mountains (American Ornithologists’ Union 1983, Brown 1999). The species
breeds mostly in woodland, forest, and coastal habitats (Brown 1999). Riparian areas and coastal and
inland wetlands are important habitats year-long, especially in the non-breeding seasons. During
migration, the peregrine falcon frequents seacoasts, marshes, lakes, and ponds with high concentrations
of waterfowl, shorebirds, and other birds. Like many other migratory birds of prey, during migration,
peregrine falcons often travel along mountain ridges on both eastern and western coastlines (Brown
1999). Within southern California, peregrine falcons are primarily found at coastal estuaries and inland
oases (Garrett and Dunn 1981). Nesting habitat usually consists of a cliff, or series of cliffs, generally
60 to 90 meters in height. Mountain valleys and river gorges with precipitous cliffs also are preferred
nest sites. Nest sites are generally located below 2,900 meters. An adequate food source is normally
found within 16 kilometers of the nest site. Peregrine falcons typically hunt within 16-32 kilometers of
nesting sites. Important hunting areas are wetlands and riparian habitats; meadows and parklands; crop
lands such as hayfelds, grainfields and orchards; and areas such as gorges, mountain valleys and lakes
over which prey are vulnerable.
As the peregnne falcon increased in numbers, following the ban on DDT and concurrently with
releases of captive-bred birds, pairs became established in many urban areas. In 1994, at least 75 pairs
nested in at least 50 urban areas in the United States (Cade et al. 1994). In 1999, at least 117 pairs
nested in urban areas in the U.S. (U.S. Fish and Wildlife Service 1999). Nest sites are provided in
uhan areas by buildings, bridges, smokestacks and other miscellaneous structures. Urban nesting by
peregnne falcons is a significant factor in the recovery of some regional populations. In the
Midwestern U.S. in 1993,31 of 43 successful pairs nested in urban areas. It may be possible for
peregrine falcon populations to exceed their known historical high populations due to the availability
of urban nest sites (Cade et al. 1994). Abundant rock doves (Columbu Ziviu) are a major food source
of urban peregrines. In the last decade, San Diego has supported up to two breeding pairs per breeding
season.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 129
Life Histdry
The peregrine typically hunts its prey in air and prey is either struck to the ground or killed outright by
a blow from the talons. They will also pursue prey in a low, fast flight, or attack passing birds from a
perch. Some pairs hunt cooperatively with the larger female diving for the prey first and then if
successful, eating first from the prey item (Brown 1999). The species may fly 16 to 19 kilometers from
their nest in search of prey which are usually hunted over open habitat-types such as waterways, fields
and wetland areas such as swamps and marshes (Dudek and Associates 2oooC). In general, the
peregrine falcon frequents bodies of water in open areas with cliffs and canyons nearby for cover and
nesting and is located in areas with abundant avian prey (Zeiner et al. 1990). The peregrine falcon will
primarily eat pigeon-size birds but may feed on large numbers of lemmings and voles when present
(Brown 1999). The diet of this species includes jays, flickers, meadowlarks, pigeons, starlings,
shorebirds, waterfowl and other readily available species. Due to their larger size, the females may take
larger prey items.
Breeding occurs from early March to late August. The nest site, which is often referred to as an eyrie,
usually consists of a rounded depression, or scrape (Call 1978), with accumulated debris that is
occasionally lined with grass. Clutch size varies from three to seven eggs with incubation at 28 to 35
days performed by both parents (Brown 1999). The young typically fledge from the nest between 25
and 42 days (Brown 1999). The young are not independent of the parents for several months. If the
first eggs are removed or destroyed early in the season, a second clutch is possible (Brown 1999).
Peregrines compete with ravens and prairie falcons (Fulco mexicanus) for nesting sites (Zeiner et al.
1990).
The hatching success of the species in the wild is about 75 percent. The juvenile birds continue to be
particularly vulnerable during their first year of life as they learn to hunt and develop flying skills.
Enderson (1969) estimated annual juvenile mortality at approximately 70 percent and adult mortality at
approximately 25 percent. The mean life expectancy for those young that fledge is approximately four
years. The maximum life span of the peregrine is in excess of 13 years. It is possible that a few
individuals may reach 20 years of age.
Little is known of post-breeding movements of adults or immatures (U.S. Fish and Wildlife Service
1984). Within the Midwest, dispersal from hack or natal sites has a large variation, however the mean
dispersal distance of females, at 320 kilometers, is about twice that of males, at 176 kilometers.
Fidelity to the territory is strong, but territorial shifts do occur (Tordoff and Redig 1997). In the Rocky
Mountains, the home range included the area encompassed by a radius up to 23 kilometers from cliff
nests (Zeiner et al. 1990). Cade (1960) found a minimum territory of about a 100 meter radius around
peregrine nests in Alaska. White and Cade (1971) reported that the mean spacing between nests was
9.7 kilometers along Alaska rivers. In some parts of California, the home range averages 325 square
kiIometers and territories are spaced approximately 5 to I1 kilometers apart (Zeiner et al. 1990). The
species is most likely to be found where prey (primarily birds) concentrate. In resident birds,
pair-bonds remain established year-round (Brown 1999).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 130
Papulatiin Trend
Populations declined precipitously in North America in the 1950s, continuing into the 1970s. Declines
were attributed to eggshell thmning and nesting failure as a result of the use of organochlorine
pesticides (e.g., DDE, DDT, and DDD). These compounds accumulated in the birds as a result of
feeding on contaminated prey, affecting their reproductive potential through interference with calcium
metabolism. The eggs were laid with thin shells, rendering them easily broken and consequently,
greatly affecting the species' reproductive success (Ambrose 2000). Breeding populations in the
eastern and southem regions of the United States were extirpated. In the 1980s, there was a general
increase in reproductive success generally attributed to the ban on the use of DDT in the United States
in 1972 (U.S. Fish and Wildlife Service 1999).
In conjunction with the prohibition of the use of DDT in the U. S., wild peregnne falcon populations
were augmented with the release of captive-bred birds. In California from 1977 to 1992,702 peregrine
falcons were released through the captive breeding program (California Department of Fish and Game
1999). Wooton and Bell (1992) developed a model for predicting viability of the falcon population
given different management strateges. The model fit known yearly data from California between
1980-1989. The model indicated that the California population, given current management techniques,
would not be sustainable without further intervention. Furthermore, they predicted that enhancing adult
survivorship is more effective than enhancing fledgling success and that efforts should be concentrated
in northern California where populations are more dense in order to achieve a viable population.
Wooton and Bell (1992) predicted that as a viable population, the northern California population
would exhibit a source-sink dynamic between subpopulations. Recovery goals for American peregrine
falcons in the United States were substantially exceeded in some areas, and in August 1999 the
American peregrine was removed from the List of Endangered and Threatened Wildlife and Plants (64
FR 46541).
Mexican border was 224 pairs in 1995, with more than 120 pairs occurring in California. The Pacific
coast population currently has 270 pairs with productivity estimated at 1.5 young per pair.
The population of peregrine falcons along the Pacific coast from Washington to the
Threats
Eggshell thinning from residual organochloride pesticides in the environment continues to be a
problem in southern California (U.S. Fish and Wildlife Service 1999). Removal of wetland and
grassland habitat, among other types, by development is also a threat to this species.
Environmental Baseline
Peregrine falcons have been detected in Carlsbad, Encinitas, and Escondido foraging at Batiquitos
Lagoon, Lake Hodges, and the San Pasqual Valley, but have not been known to nest there. There are
no major populations in the MHCP; however, all coastal wetlands and lagoons are considered critical
locations for foraging. There is 4,574 acres of suitable peregrine falcon habitat (estuarine, marsh, and
riparian vegetation) in the MHCP planning area.
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 13 1 -
The City of Carlsbad includes 1,856 acres of grassland, 574 acres of riparian habitat, and 1,366 acres
of marsh. 'Though the aforementioned habitat types are the most likely to be used for foraging,
peregrines may also forage over the 3,315 acres of coastal sage scrub, 968 acres of chaparral, 392 acres
of southern maritime chaparral, 29 acres of oak woodland, 258 acres of eucalyptus woodland, and
1,812 acres of agricultural areas in the plan area. Agricultural areas within the plan area are primarily
in 2 large blocks. There are approximately 285 acres of agricultural land on Robertson Ranch, and
400-500 acres in the block that lies between the Tchang property and Holly Springs, consisting of
several properties, including the Cantarini, Mandana, and Kat0 properties.
Though peregnnes may forage in the sky over any habitat in the MHCP area, Coastal lagoons are the
most important peregrine falcon habitat in the subregion. There have been documented observations at
Buena Vista Lagoon, Buena Vista Creek, and Batiquitos Lagoon. Service personnel have observed
peregrine falcons at Batiquitos and San Elijo Lagoons, Bressi Ranch, Carlsbad Oaks North, and the
site of the proposed municipal golf course (John Martin, USFWS, pers. obs.). The Subarea provides
good foraging habitat (coastal lagoons), but lacks suitable topography in undisturbed areas for nesting.
Carlsbad has the potential to support nesting peregrines in the future if suitable tall buildings are
constructed. Agricultural areas provide an alternative foraging area. Peregrines have been observed
foraging at Bressi Ranch, but this site has been recently permitted for development. Current survey
information is lacking for this species, but within the Subarea and the MHCP, foraging and wintering
grounds are still available.
Effects of the Action
Direct Eflects
The MHCP Subregional Plan conserves 100 percent of the 4,574 acres of coastal lagoon habitat within
the MHCP used by peregrine falcon for foragtng. In addition, the no-net-loss of wetlands, condition of
coverage (no take of indviduals or nets, including by harassment, is allowed), and conditions for
estuarine species policies will ensure no direct impacts will occur to this species. Lastly, this species is
not known to nest if the MHCP planning area, so no direct impacts to nests, nesting behavior, or chicks
are expected.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve since Caltrans and the Federal Highway
Administration is not a participant to this MHCP. Any impacts that may occur in the future in these
right-of-ways due to projects such as road widening would be analyzed and permitted under a different
mechanism than the MHCP.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 132
A small amount of additional habitat in the lagoons are technically not in the mapped area of the
preserve, however, no projects are planned for this area by the City and 100 percent conservation due
to MHCP standards for avoidance, minimization, and mitigation of wetland impacts assure no-net-loss
of lagoon wetland habitat. However, impacts can occur to such wetland communities as described in
section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated according to
section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there
could be a temporal loss of such functions and values. The MHCP conditions for estuarine species and
fact that all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due
to these standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine,
salt marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, indirect effects will be
minimized because any areas proposed for disturbance would be avoided where MHCP species or
nests are known or found to be present. All of the suitable peregrine roosting habitat is included within
the preserve. The preserve includes nearly all of the open water in the lagoons, which may
occasionally serve as peregrine foraging habitat. Thus, because peregrines do not nest in the MHCP
planning area and there will be no-net-loss of foraging area, and the quality of foraging habitat will not
be significantly degraded due to the conditions for estuarine species, no direct impacts to peregrine are
expected from implementing the MHCP nor the HMP.
Implementation of the plan may result in impacts to 3,025 acres of undeveloped wildlife habitat that
may be used by peregrine falcons, including 1,176 acres of coastal sage scrub, 292 acres of chaparral,
50 acres of southern maritime chaparral, 80 acres of riparian, 5 acres of oak woodland, 114 acres of
marsh, 159 acres of eucalyptus woodland, and 1,149 acres of grassland. Conversely, 2,139 acres of
coastal sage scrub, 676 acres of chaparral, 342 acres of southern maritime chaparral, 24 acres of oak
woodland, 494 acres of riparian, 1,252 acres of marsh, 99 acres of eucalyptus woodland, and 707 acres
of grassland would be preserved. Though the amount of agricultural land that would be potentially
impacted by the plan is not quantified, the large blocks of agricultural land in the plan area will
probably be converted primarily to urban uses. However, the such impacts are not expected to result in
a decrease in the number of American peregnne falcons that would use the I”CP planning area not
the City’s planning area, especially due to the maintenance of the lagoon areas.
Indirect Eflects
Indirect impacts include the proliferation of exotic species, as generally explained and applicable in the
“General Indirect Effects” section. Invasive exotic plant species have the potential to adversely affect
foraging habitat and prey availability.
Water quality controls and adjacent habitat development can create edge effects potentially impacting
prey abundance for this species. The lack of known nesting habitat in the MHCP planning area
precludes analysis of loss of nesting habitat. This species may also be particularly susceptible to
pesticides. As a result of the measures incorporated into the Subarea Plan and the MHCP, we
anticipate few indirect impacts to this species. However, incorporation of the following conservation
measures into the plan will help minimize these effects:
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species dependent on estuarine habitats (e.g., California least tern,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 133 -
light-footed clapper rail, western snowy plover, Belding’s savannah sparrow, etc.). These measures are
intended tb mini&ze indirect impacts to estuarine species. Though these measures are not explicitly
required for coverage of the peregrine falcon under the HMP, they are required for coverage of the
species mentioned above, and peregrines are likely to benefit from their implementation. Measures
include regulation of adjacent land use, recreational access, mosquito control, noise, vehicle access,
potential pollutants, access during breeding season, camping and picnicking; area-specific management
measures including fencing, animal and plant pest control, habitat enhancement andor creation, trash
removal, erosion control, maintenance of tidal flushing; monitoring of covered species populations,
biodiversity, habitat area, effect of recreation on wildlife, pest animal and plant populations, use by
migratory birds, and success of restoration efforts; and development of public awareness program
including public participation in management, development of community outreach programs, and
improvement of trails and facilities to focus public access.
Management is expected to occur initially since all species points in the City are within managed areas,
such as the lagoons by California Department of Fish and Game.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this species
as described above. No direct impacts are expected from the MHCP Subregional Plan or City’s
Subarea Plan due to 100 percent conservation at the coastal lagoons, estuaries, and riparian habitat,
condition of coverage for this species, and the conditions for estuarine species. This species will also
benefit from the wetland buffer and critical locations policies. The MHCP Subregional Plan and
City’s Subarea Plan will provide monitoring and management of this species that will detect and
minimize negative impacts that are affecting American peregrine falcons. Additionally, this species
will benefit from a foraging aspect by the connected preserve system that will be managed and
monitored in the City and throughout the MHCP in perpetuity. This Preserve will be adaptively
managed, per the measures included in the MHCP Subregional Plan, which will further reduce the
indirect effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional and the City’s Subarea Plans
are not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
No take of peregrine falcon individuals or nests, including by harassment, will occur as a result of the
MHCP Subregional and City’s Subarea Plans due to the MHCP condtion of coverage, no-net-loss of
wetland policy, and conditions for estuarine species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 134
RaZZus Zongirostris Zevipes (Light-footed clapper rail)
Status of the SDecies
Listing Status
The light-footed clapper rail was listed as federally endangered on October 13, 1970 (35 FR 16047)
and State endangered in California on June 27, 1971. The original recovery plan for this species was
approved in July 1979 and a revision was published on June 24, 1985 (U.S. Fish and Wildlife Service
1985a). Critical habitat has not been designated for this species. The light-footed clapper rail is a fully
protected species by the State.
Species Description
RaZZus longirostris Zevipes is a hen-sized marsh bird belonging to the family Rallidae, in the order
Gruiformes. It is approximately 36 centimeters in total length. It has a slightly down-curved bill
longer than the head, and a short, upturned tail. Its long legs and toes are dull yellowish-gray. Males
and females are identical in plumage. The cinnamon breast contrasts with the streaked plumage of its
grayish-brown back and gray and white barred flanks. Most of the side of the head, including the
cheek and lores, are gray. The chin and throat, and a line from the base of the bill to the top of the eye,
are very light buff.
Eddleman and Conway (1998) describe 25 subspecies of clapper rail (RaZZus Zongirostris) which they
divide into 3 groupings: the obsoletus group of western North America; the crepitans group of eastern
North America, the Caribbean, and the Yucath; and the Zongirostris group of South America. The
light-footed clapper rail is one of four subspecies in the obsoletus group, three of which are formally
recognized as endangered by the Federal government and endangered or threatened by the State of
California (U.S. Fish and Wildlife Service 1985a). There is very little divergence in mitochondrial
DNA among subspecies yumanensis, Zevipes, obsoletus, crepitans, and saturatus (Fleischer et al.
1995). Subspecies yumanensis and Zevipes probably had a common ancestor within the last 50,000
years, but mini-satellite and Randomly Amplified Polymorphic (RAPD) DNA differences suggest little
genetic interchange between the two (Fleischer et aZ. 1995). A detailed description of the taxonomic
history of the light-footed clapper rail is presented in the recovery plan and is hereby incorporated by
reference.
Distribution
Light-footed clapper rails inhabit coastal marshes from the Carpinteria Marsh in Santa Barbara County,
California, to Bahia de San Quintin, Baja California, Mexico (Zembal 1989, Zembal et al. 1998). It is
believed that most salt marshes along the coastline at one time supported clapper rails (Grinnell et al.
1918). However, recent census data indicate that less than 50 percent of the coastal wetlands in
California are currently occupied (Zembal et al. 1998).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 135
Habitat Aflnity
The light-footed clapper rail uses coastal salt marshes, lagoons, and their maritime environs (Zembal
1989). The birds nest in the lower littoral zone of coastal salt marshes where dense stands of cordgrass
(Spartina foliosa) are present, occasionally in pickleweed (Salicomia virginica) (Massey et al. 1984).
Nesting habitat includes tall, dense cordgrass in the low littoral zone, wrack deposits in the low marsh
zone, and hummocks of high marsh within the low marsh zone (Massey et al. 1984). Fringing areas of
high marsh serve refugia during high tides (Zembal et al. 1989, Shuford 1993). Although used
infrequently, this habitat may be extremely important at reducing mortality during high tides. Light-
footed clapper rails have also been known to reside and nest in freshwater marshes, although this is not
common (Thelander and Crabtree 1994). They require shallow water and mudflats for foraging, with
adjacent higher vegetation for cover during high water (Zeiner et al. 1990).
Life History
Light-footed clapper rails are most active in the morning, three hours after sunrise and in the evening,
three hours before sunset (Zembal et al. 1989). Foraging activity is greatest in the early morning, while
vocalizing shows a strong peak just before dark (Zembal et al. 1989). Activities are also tide-
dependent (Zembal et al. 1989). Light-footed clapper rails forage in all parts of the saltmarsh,
concentrating their efforts in the lower marsh when the tide is out, and moving into the higher marsh as
the tide advances. The rails are omnivorous and opportunistic foragers, which rely mostly on salt
marsh invertebrates such as beetles (Coleoptera), garden snails (Helix spp.), California hornsnails
(Cerithidea califomica), salt marsh snails (Melampus olivaceus), fiddler and hermit crabs (includmg
Pachygrapsus crassipes, Hemigrapsus oregonensis, and probably Uca crenulata), crayfhh, isopods,
and decapods (Jorgensen 1975, U.S. Fish and Wildlife Service 1985a). This species may also forage
on frog tadpoles (Hyla spp.), California killifish (Fundulus pawipinnis), and even California meadow
mice (Microtus califomicus) (U.S. Fish and Wildlife Service 1985a). The rails ingest some vegetable
matter, including Spartina stems and Salicomia tips (U.S. Fish and Wildlife Service 1998) but this is
uncommon (Zembal 1989).
The pair bond in light-footed clapper rails endures throughout the season, and often from year to year.
Nesting usually begins in March and late nests have usually hatched by August. Nests are placed to
avoid flooding by tides, yet in dense enough cover to be hidden from predators and to support the
relatively large nest (Storey et al. 1988). Typical nests in Spartina are elevated 10-45 centimeters
above the ground. The outside edges of nesting platforms are typically woven into the sunoundmg
live cordgrass which secures the nest as it floats during high tide. Nests typically include one or two
ramps of vegetation leading to the ground, and a loosely-woven canopy of live stems and leaves (U. S.
Fish and Wildlife Service 1985a). Females lay approximately 4-8 eggs, which hatch in 18-27 days
(U.S. Fish and Wildlife Service 1985a). Both parents care for the young; while one forages, the other
adult broods the chicks (U.S. Fish and Wildlife Service 1985a). By the age of two days, chicks will
accompany adults on foraging trips, however, adults have been observed feeding fully grown chicks of
at least six weeks of age within twenty-five meters of their incubation nest (U.S. Fish and Wildlife
Service 1985a). In addition to the primary nest, in which the birds incubate eggs, adult clapper rails
construct brood nests after the young have hatched. Rail chicks are brooded by adults in the brood
nests, which differ from the incubation nests in the lack of ramps and canopies.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 136 -
Potential predators on eggs, nestlings, or adults include California ground squirrels (Spemzophilus
beecheyi), old world rats (Rattus spp.), striped skunk (Mephitis mephitis), feral house cats (Felis catus),
dogs (Canis familiaris), gray fox (Urocyon cinereoargenteus), red fox (Vulpes vulpes), Virginia
opossum (Didelphis marsupialis), and a variety of raptors (U.S. Fish and Wildlife,Service 1985a).
Very limited evidence exists for intermarsh movements by light-footed clapper rails. This subspecies
is resident in its home marsh except under unusual circumstances (Zembal 1989). Within-marsh
movements are also confined and generally of no greater spread than 400 meters (Zembal 1989).
Minimum home range sizes for 9 clapper rails that were radio-harnessed for telemetry at Upper
Newport Bay varied from approximately 0.8 to 4.1 acres (Zembal 1989). The larger areas and daily
movements were by first year birds attempting to claim their first breeding territories (Zembal 1989).
Population Trend
The number of marshes inhabited by breeding clapper rails in coastal southern California has
fluctuated widely since the population censuses began in 1980. The number of occupied marshes
declined from 19 marshes in 1984 to 8 marshes in 1989 (Zembal et al. 1998). During the 1990s there
was a general increase in the number of occupied marshes, with 16 occupied marshes in 1997.
In 1972-73 the first census of the rail in southern California was conducted, and the population was
estimated at about 500 pairs (Wilbur 1974). In 1981 only 203 pairs were found (Zembal and Massey
198l), and the highest count through 1984 was 277 pairs (Zembal and Massey 1985). The population
crashed in 1985 to below 150 pairs, and remained below 200 pairs until 1991 when the population was
estimated at 235 pairs (Zembal 1992, Zembal et al. 1998). In 1997 the population had increased to
307 pairs (Zembal et al. 1998). In 2001 the population had decreased to 217 pairs at 14 marshes
(Zembal and Hoffman 2004).
Southern California’s largest subpopulation of light-footed clapper rails, located in the Upper Newport
Bay, has been singularly resilient since 1980, whereas all of the other subpopulations have exhibited
more vulnerability to fluctuations in environmental conditions (Zembal et al. 1998). The Upper
Newport Bay subpopulation has been 38-71 percent of the California total since 1980 and was 48.5
percent of the total in 1997 (Zembal et al. 1998). It has usually consisted of 100 pairs of rails or more
and has recovered quickly the few times that it dropped lower. In 1996, it was as high as ever recorded
and that level was nearly maintained in 1997 (Zembal et al. 1998). In contrast, the second and third
largest subpopulations at Tijuana Marsh and Seal Beach NWR have been dramatically affected by
major environmental perturbations. At Tijuana Marsh, detectable clapper rail breeding activity was
eliminated in 1985, following closure of the ocean inlet and the disappearance of tidal influence
(Zembal et al. 1998). At the Seal Beach NWR, heavy predation ensued over several years as
mesopredator release (Soul6 et al. 1988) resulted from the disappearance of native top carnivores,
particularly the coyote (Canis latrans), and an explosion in the local population of non-native red foxes
(Vulpes vulpes). This resulted in the near elimination of clapper rail breeding at Seal Beach. The
subpopulations have subsequently rebounded, but only after many years of intensive management.
The subpopulation at Tijuana Marsh is holding strong with over 50 breeding pairs, whereas at Seal
Beach, there were declines of 29 percent in 1995 and again in 1997 (Zembal et al. 1998). The three
largest subpopulations comprised 85.7 percent of the breeding clapper rails on the coast of southern
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 137 -
California in 1997 (Zembal et al. 1998). All other subpopulations have contributed 10 to 37 percent of
the Califohia total since 1980 (Zembal et al. 1998). Each of the smaller subpopulations is under
constant threat of extirpation, whereas with proper monitoring and management any one could become
a nucleus for recovery (U.S. Fish and Wildlife Service 1985a).
Threats
Destruction of coastal wetlands in southern California has been extensive. Many estuaries where light-
footed clapper rails were once abundant have been reduced to remnants. San Diego Bay once had
2,450 acres of salt marsh, and now has 360 acres (85.3 percent loss); Mission Bay was reduced from
2,400 acres to 21 acres (99.2 percent loss); and the Los Angeles-Long Beach wetlands which once
covered 6,800 acres are now a remnant 70 acres (99.0 percent loss) (U.S. Fish and Wildlife Service
1985a). Although salt-marsh habitat loss, degradation, and fragmentation are the leading threats to
light-footed clapper rails, they are also threatened by disturbance, diseases, contarninants, and
predation by non-native red foxes (Thelander and Crabtree 1994). They may also be hit by vehicles in
marshes bisected by roads (Zembal et al. 1989, John Martin, USFWS, pers. obs.).
Severe storms and excessive runoff can adversely affect rails, by tearing away or matting down patches
of cordgrass to the extent that rails cannot use them for nesting or cover (U.S. Fish and Wildlife
Service 1985a).
Environmental Baseline
Within the MHCP planning area, major populations of clapper rails occur in San Elijo, Batiquitos,
Agua Hedionda, and Buena Vista lagoons. Within the MHCP area, clapper rails also occur at the
mouth of the San Luis Rey River (Zembal pers. comm.) and at San Elijo Lagoon, where surveys
between 1990-2001 detected 1-8 pairs (Zembal unpubl. data). Due to the species rarity, all populations
at the lagoons are considered major and critical locations. There is 272 acres of suitable clapper rail
habitat (southern coastal salt marsh vegetation) in the MHCP planning area.
In the City of Carlsbad, Buena Vista, Agua Hedionda, and Batiquitos lagoons support approximately
151 acres of southern coastal salt marsh habitat. Yearly surveys initially documented pairs and single
birds in 1980 at Aqua Hedionda Lagoon, with no presence Batiquitos or Buena Vista lagoons. The
number of birds within the subareas had declined to zero by 1986. In 1990 unpaired rails (population
sizes unknown) were documented in Buena Vista Lagoon and Batiquitos Lagoon, whle rails were not
found in Agua Hedonda Lagoon until 1997. Breeding pairs were first recorded in the Subarea in 1991
at Buena Vista Lagoon. In 1997 the total population at all Subarea lagoons reached a total of 10 pairs
(minimum of 21 individuals) and in 2002 there were 14 pairs (30 individuals) (Zembal unpubl. data
and pers. comm).
Previous impacts to rails may have resulted from the dredging of Aqua Hedionda Lagoon. It was
initially dredged in 1954 to provide a source of cooling water for San Diego Gas & Electric
Company’s Encina Power Plant. Since 1954, the outer lagoon undergone periodic maintenance
dredging, while no dredging had occurred in the middle and inner lagoons. The outer lagoon is
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 138 -
dredged every one to three years. In 1998 SDG&E was permitted to dredge Aqua Hedionda’s middle
and inner lagoons and discharge the dredged material (spoil) on the Encina Power Plant jetty and a
borrow pit created in the lagoon. Potential impact to cattail habitat occupied by the light footed clapper
rails resulting from increased salinity levels was offset by SDG&E by the reintroduction of cordgrass
near the mouth of Aqua Hedionda Creek.
Batiquitos Lagoon has also experienced extensive restoration. Restoration of &us seasonal tidal
waterbody was initiated in 1994 and completed in 1996. It resulted in the continuous tidal exchange of
Pacific Ocean waters. Since re-establishment of tidal influence, clapper rails have colonized Batiquitos
lagoon (Zembal, unpubl. data). The inlet channel to Batiquitos Lagoon was dredged in 2000 The areas
adjacent to the Subarea lagoons have been extensively developed.
Effects of the Action
Direct Effects
The MHCP Subregional Plan requires the following condition be met for a city to receive coverage for
this species: As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist possessing a Section 10(a)l(A) research permit for this species must
survey all areas containing suitable habitat for this species using approved survey protocols. Any take
of habitat must be mitigated in part by creating or enhancing light-footed clapper rail habitat andor
establishing new populations in reserve areas. Possible restoration and enhancement actions include
revegetation of cordgrass and pickleweed vegetation, and providing nesting platforms in potential
nesting habitat. All of the coastal lagoons within the MHCP planning area will be 100 percent
conserved and the conditions for estuarine species (MHCP Appendix E) would benefit this species.
Thus, no direct impacts are expected to occur to this species from the MHCP Subregional Plan.
.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (15 1 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve since Caltrans and the Federal Highway
Administration is not a participant to this MHCP. Any impacts that may occur in the future in these
right-of-ways due to projects such as road widening would be analyzed and permitted under a different
mechanism than the MHCP.
A small amount of additional habitat in the lagoons are technically not in the mapped area of the
preserve, however, no projects are planned for this area by the City and 100 percent conservation due
to MHCP standards for avoidance, minimization, and mitigation of wetland impacts assure no-net-loss
of lagoon wetland habitat. However, impacts can occur to such wetland communities as described in
section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated according to
section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 139 -
could be a temporal loss of such functions and values. The MHCP conditions for estuarine species and
fact that dl the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due
to these standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine,
salt marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, indirect effects will be
minimized because any areas proposed for disturbance would be avoided where MHCP species or
nests are found to be present. All of the suitable light-footed clapper rail nesting habitat is included
within the preserve. Thus, because there will be no-net-loss of foraging area, and the quality of
foraging habitat will not be significantly degraded due to the conditions for estuarine species, no direct
impacts to light-footed clapper rail are expected from implementing the MHCP nor the HMP.
Zndirect Efects
Indirect impacts have the potential to cause significant adverse affects to light footed clapper rails
within the action area. These indirect impacts include night lighting, human disturbance, depredation
by domestic pets, and habitat degradation, as generally explained and applicable in the “General
Indirect Effects” section.
Specifically, indirect impacts to the light footed clapper rail could result from the degradation of
estuarine and salt marsh habitats. These impacts could include adverse changes in the hydrology or
water quality of salt marsh and estuarine habitats. Increased freshwater flow could decrease the
salinity of salt- or brackish-marshes, thus leading to vegetation type conversion of rail habitat.
Contaminants that may affect aquatic organisms, including rail prey, in the lagoons may be carried to
the lagoon by storm water runoff from throughout the watershed. Developed areas are sources of non-
point source pollution. Development also increases the amount of impervious surface in the
watershed, increasing the velocity and volume of storm water runoff, thus exacerbating conveyance of
non-point source pollution in storm water runoff. Therefore, development throughout the MHCP
planning area may affect clapper rails and their lagoon habitat. Also, adverse edge effects resulting
from increased human traffic may deter light-footed clapper rails from nesting. Specifically, indirect
impacts to the clapper rail could result from increases in human use of areas adjacent to lagoons
associated with conversion of agricultural areas to urban uses at the proposed Hub Park at the
southeast comer of Agua Hedionda Lagoon and the farmland at the northeast comer of Batiquitos
Lagoon.
The Subarea plan provides a basis for the conservation of this species and its associated habitats by
requiring the following:
1. Manage preserve areas to control non-native plants, maintain hydrology and water quality,
control predators, and restrict physical dsturbances. Where opportunities arise, restore and
enhance habitat in preserved areas. Restnct human activity near nesting habitat during the
breeding season (April 1 through August 31). Where appropriate, introduce Clapper Rails into
suitable, unoccupied habitat. Pursue experimental cordgrass reintroduction at Batiquitos
Lagoon.
Appendix E (Condltions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the light-footed clapper rail) dependent
on estuarine habitats. These measures are intended to minimize indirect impacts to rails and
2.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 140 -
other estuarine species. Measures include regulation of adjacent land use, recreational access,
mosquito control, noise, vehicle access, potential pollutants, access during breeding season,
camping and picnicking; area-specific management measures including fencing, animal and
plant pest control, habitat enhancement and/or creation, trash removal, erosion control,
maintenance of tidal flushing; monitoring of covered species populations, biodiversity, habitat
area, effect of recreation on wildlife, pest animal and plant populations, use by migratory birds,
and success of restoration efforts; and development of public awareness program including
public participation in management, development of community outreach programs, and
improvement of trails and facilities to focus public access.
Maintenance of tidal flushing, as a required condition for estuarine species, will help to avoid
reproductive failure of rails such as that which occurred concurrently with the closure of the mouth of
the Tijuana River in 1985. In addition, management will begin initially for this species since it occurs
in the lagoons which will be managed by California Department of Fish and Game.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this species
as described above. No direct impacts are expected from the MHCP Subregional Plan or City’s
Subarea Plan due to 100 percent conservation at the coastal lagoons and because the MHCP requires
all direct effects to individuals, nests, or young to be avoided. This species will benefit from the no-
net-loss of wetlands, wetland buffer and critical locations policies. The MHCP Subregional Plan and
City’s Subarea Plan will provide monitoring and management of this species that will detect and
minimize negative impacts that are affecting light-footed clapper rail. Additionally, ths species will
benefit from a foraging aspect by the connected preserve system that will be managed and monitored
in the City and throughout the MHCP in perpetuity. Th~s Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline for
the action area, the effects of the proposed action, and the cumulative effects, it is the Service’s
biological opinion that the MHCP Subregional and the City’s Subarea Plans are not likely to
jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
No take of light-footed clapper rail individuals or nests, including by harassment, will occur as a result
of the MHCP Subregional and City’s Subarea Plans due to the direct effect avoidance measures, no-
net-loss of wetlands policy, and conditions for estuarine species policy.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 141
Charudrius aledrinus nivosus (Western snowy plover)
Status of the Swcies
Listing Status
The Pacific coast population of the western snowy plover was listed as federally threatened on March
5, 1993 (58 FR 12864). Critical habitat was designated for the western snowy plover on December 7,
1999 (64 FR 68508) and a draft Recovery Plan was published in the Federal Register in August 2001
(66 FR 42676).
Species Description
The snowy plover is a small (15-17 centimeters long, weighing approximately 34-58 grams), pale-
colored shorebird. The dark breast band common to the genus is restricted to dark patches on either
side of the upper breast. Underparts are whitish from the chin to the undertail coverts, while
upperparts, including wings, back, and uppertail coverts, are light sandy brownish-gray from the mid-
crown posteriorly. The forecrown and auricular region are blackish. The face is white except for the
dark auricular. The eye is moderately large and dark brown. The bill is short, straight, slightly tapered
throughout its length, and blackish. The legs are of medium length and blackish. In flight, the
primaries and primary coverts appear darker than the rest of the wing, and the central rectrices are
darker gray than the rest of the tail. The species was first described in 1758 by Linnaeus (American
Ornithologists’ Union 1957). Two subspecies of the snowy plover are recognized in North America,
the western snowy plover and the Cuban snowy plover (C. A. tenuirostris) (Page et al. 1995). The
Pacific coast population of the western snowy plover is defined by the U.S. Fish and Wildlife Service
(1993) as those individuals that nest adjacent to or near tidal waters, and includes all nesting colonies
on the mainland coast, peninsulas, offshore islands, adjacent bays, and estuaries.
Distribution
The breeding range of the snowy plover extends along coastal beaches from the southern portion of
Washington state to southern Baja California, Mexico. The coastal population consists of both
resident and migratory birds. Some birds winter in the same areas used for breeding, whereas others
migrate either north or south to winter (Warriner et aE. 1986). The breeding and winter distribution of
the snowy plover in California is along coastal sandy beaches, dunes, and estuarine habitat. It is a
common migrant and winter visitor and localized breeding resident in San Diego County (Unitt 1984).
In recent years, snowy plovers have nested at fourteen sites within San Diego County (Powell et al.
1996). Within the Subarea, westem snowy plovers regularly nest at Batiquitos Lagoon (Powell et al
1998, Kevin Clark USFWS, pers. corn.). Elsewhere within the MHCP area, snowy plovers have
nested at Agua Hedionda Lagoon (Page and Stenzel 1981)
Habitat Afinity
Sand spits, dune-backed beaches, sparsely to unvegetated beach strands, open areas around estuaries,
and beaches at river mouths are the preferred coastal nesting areas of the snowy plover (U.S. Fish and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 142 -
Wildlife Service 1993, Small 1994). Other areas utilized by nesting snowy plovers include dredge
spoil fill, dry salt evaporation ponds, and salt pond levees (U.S. Fish and Wildlife Service 1993, Small
1994). The majority of snowy plovers exhibit site fidelity, returning to the same breeding location in
subsequent years. Habitat suitability is contingent upon isolation from human Qsturbance and
predation.
Critical Habitat
Critical habitat was designated for the snowy plover on December 7, 1999 (64 FR: 68508). The
designation included coastal habitat from Grays Harbor County, Washington, south to San Diego
County, California. The primary constituent elements are found in areas that support intertidal beaches
(between mean low water and mean high tide), associated dune systems, and river estuaries and
include: (1) surf-cast kelp, (2) sparsely vegetated foredunes, (3) interdunal flats, (4) spits, (5) washover
areas, (6) blowouts, (7) intertidal flats, (8) salt flats, (9) flat rocky outcrops, and (10) gravel bars.
Several of these components (e.g., sparse vegetation, salt flats) are mimicked in artificial habitat types
used less commonly by snowy plovers (Le., dredge spoil sites and salt ponds and adjoining levees).
There is no critical habitat within Carlsbad or the MHCP area.
Life History
Snowy plovers forage for terrestrial and aquatic invertebrates on beaches above and below the mean
high-water line, gathering food from the surface of the sand, kelp, marine-mammal carcasses, or low
foredune vegetation (Page et al. 1995). Plovers will pause, look, run, and then seize prey from the
surface of the beach or tide flat (Page et al. 1995). They will sometimes probe in the sand, particularly
at the base of low growing plants to forage above the high-tide line (Page et al. 1995).
Snowy plovers breed in loose colonies with the number of adults at coastal breeding areas ranging
from 2 to 318 (Page and Stenzel 1981). The breeding season of the snowy plover extends from March
1 through September 15. Generally, three eggs are laid in a nest which consists of a shallow
depression scraped in sandy or saline substrates. Both sexes incubate the eggs. Snowy plover chicks
are precocial, leaving the nest within hours of hatching to search for food and rarely remain within the
nesting territory (Warriner et al. 1986).
Young snowy plovers are able to fly within approximately 31 days of hatching. The fledging success
of snowy plovers varies greatly by location and year and sometimes snowy plovers nesting on
neighboring beach segments may exhibit significantly different success in the same year (U.S. Fish and
Wildlife Service 1999). In San Diego County, the fledging rate of chicks ranged from 32.6 to 51.4
percent (mean = 41 percent) from 1994 through 1996 (Powell et al. 1996).
Population Trend
Prior to 1970, snowy plovers bred at 53 locations along coastal California (Page and Stenzel 1981).
By 1991, there were a total of 20 breeding areas with eight areas supporting 78 percent of the coastal
California breeding population (Page et al. 1991). While no historical numbers have been reported for
snowy plovers, the breeding population in California was estimated to be less than 1,400 adults in
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 143
1989 (Page et al. 1991). In 1996, the San Diego County population was estimated to be 272
individuds, including 122 females (Powell et al. 1996). The 2002, San Diego County population was
estimated at 360 individuals (Copper 2002).
Threats
The population decline of the snowy plover can be correlated with industrial or residential
development andor heavy recreational use of former nesting areas (Page and Stenzel 1981). Poor
reproductive success resulting from human disturbance, predation, and inclement weather, combined
with permanent or long-term loss of nesting habitat to urban development, and the encroachment of
the introduced European beachgrass has led to the decline in active nesting colonies and wintering
populations of the snowy plover.
Environmental Baseline
In 1996, a total of 179 snowy plover nests were found at 10 sites within San Diego County with
approximately 90 percent of the nests occurring at four locations, including Marine Corps Base Camp
Pendleton (8 I), Batiquitos Lagoon (39), NAB Coronado (26), and Tijuana Slough National Wildlife
Refuge (16). In 1998, the last comprehensive San Diego County-wide survey of snowy plover nesting
sites was made by Powell et al. (1998). This survey recorded 156 snowy plover nests at nine sites
within the County, with approximately 90 percent of the nests occurring at same four sites that were
dominant in 1996. Breeding localities within the MHCP area include the San Luis Rey River mouth
and Agua Hedionda, Batiquitos, and San Elijo lagoons. Major population within the MHCP study
area occur at the San Luis Rey River mouth and the lagoon and estuarine habitats in Encinitas,
Carlsbad, and Oceanside, all of which are considered critical locations. The lagoons also have the
potential for western snowy plovers to support wintering birds in the MHCP planning area.
The City of Carlsbad includes approximately 1,366 acres of habitat classified as marsh (southern
coastal salt marsh and freshwater marsh). Buena Vista, Agua Hedionda, and Batiquitos lagoons
contain approximately 934 acres of estuarine and salt marsh habitat that support or potentially support
western snowy plover. However, not all of this consists of snowy plover habitat. Within this area, only
an unquantified area of open sand or mud flats around lagoons consist of suitable habitat for the snowy
plover. The HMP area contains approximately 10.2 kilometers of sandy beach along the coast.
However, virtually all is subject to heavy recreational use.
/
Within the Subarea, western snowy plovers are currently only known to nest at Batiquitos Lagoon,
where they have nested regularly since surveys were initiated in 1991. Breeding populations of this
species have been continually absent from Buena Vista and Aqua Hedionda Lagoons (Copper 2002,
Page 2002). However, historical records suggest that the snowy plover was once breeding in all
lagoons located within the Subarea (Page and Stenzel 1981). The most recent survey results (2002)
show that Batiquitos Lagoon supported 13 nests (Kevin Clark, UWFWS, pers. comm.).
Snowy plovers winter within the HMP area. Breeding sites at the lagoons all support or have the
potential to support wintering birds. Batiquitos Lagoon held 51 snowy plovers on January 8,2003.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 144 -
South Carlsbad State Beach supports wintering snowy plovers, with 22 present on January 8,2003
(~obert Pitton, pers. corn.).
Batiquitos Lagoon has experienced extensive restoration. In surveys of the lagoon'area prior to
restoration, in 1994, 5 snowy plover nests were found (Powell and Collier 2000). Restoration of the
lagoon was initiated in 1994 and completed in 1996, resulting in the continuous tidal exchange of
Pacific Ocean waters. Dredge spoils were used as beach nourishment north of the lagoon. Spoils were
also utilized to create five nesting areas for the least tern and snowy plover. In 1996 (the first nesting
season after completion of the restoration) 39 nests were found, with 38 nests in 1997 and 26 nests in
1998. The inlet channel to Batiquitos Lagoon was dredged in 2000 with a portion of dredged material
placed on the at previously created nesting sites.
Effects of the Action
Direct Eflects
The MHCP Subregional Plan requires no take of individuals or nests for this species. In addition, the
MHCP requires the following conditions be met for a city to receive coverage for this species:
1. Management will restrict activities within the preserve that could adversely affect plover
populations, including human disturbance, off-road vehicular activity, and predation of adults
and nets by domestic animals (e.g. dogs and cats) and introduced predators (e.g. red fox) or
artificially enhanced population of natural predators (e.g., gulls, raccoons, ravens, and skunks).
Human activity will be restricted by fencing off nesting areas during the breeding season (April
1 through August 31). Signs restricting access are usually not effective without fencing.
Create suitable snowy plover habitat to compensate for take by projects. Evaluate areas of
disturbed salt flats, mudflats, beach and estuarine habitats for potential snowy plover breeding
habitat enhancement and protection. Cover created breeding habitats with shells or similar
coarse materials to suppress weed growth and offer nest camouflage and scatter patches of
sticks, small rocks, dried kelp or similar debris in small amounts (15 percent cover) as hiding
cover, as directed by results of monitoring and research.
2.
3.
No direct impacts to western snowy plovers is expected from the MHCP Subregional Plan since the
plan requires no take of individuals or nests and all of the estuarine and salt flat habitat will be 100
percent conserved, most of which is withm the PA. All major populations and critical locations will
be conserved. However, only 18 percent of beach habitat is in the FPA which is used by wintering
western snowy plovers.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve. There are no projects proposed for this area,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 145 -
however, impacts may occur in the future in the right-of-ways due to projects such as road widening
which wo’uld be beyond the control of the City. Such impacts would be analyzed and permitted under
a different mechanism than the MHCP. 339 acres of southern coastal salt marsh and freshwater marsh
vegetation communities constitute potential habitat for white-faced ibis. A small amount of additional
habitat in the lagoons are also technically not in the mapped area of the preserve, however, no projects
are planned for this area by the City and 100 percent conservation due to MHCP standards for
avoidance, minimization, and mitigation of wetland impacts assure no-net-loss of lagoon wetland
habitat. However, impacts can occur to such wetland communities as described in section 3.6 of
MHCP Volume 1. Since such impacts would need to be fully mitigated according to section 4.4.2 of
MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there could be a
temporal loss of such functions and values. The MHCP conditions for estuarine species and fact that
all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due to these
standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine, salt
marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, direct take of animal
species is expected to be minimized because any areas proposed for dsturbance would be avoided
where MHCP species or nests are known or found to be present.
All of the suitable snowy plover breeding habitat on artificial tern nesting islands and salt pans in the
lagoons is included within the preserve. None of the sandy ocean beach habitat in the HMP area is
included within the preserve. This sandy beach habitat at South Carlsbad State Beach currently
supports wintering snowy plovers.
Zndirect Eflects
Indirect impacts have the potential to cause significant adverse affects to western snowy plover within
the plan area. These indirect impacts include night lighting, human disturbance, depredation by
domestic pets, and habitat degradation, as generally explained and applicable in the “General Indirect
Effects” section.
Human disturbances which have a detrimental effect to nesting snowy plovers include unintentional
disturbance and destruction of eggs and chicks by people and pets, off-road vehicle use, horse-back
riding, and beach raking. Intensive beach use by humans has resulted in abandonment of nesting sites,
and reductions in nesting density and nesting success. Specifically, indirect impacts to the snowy
plover could result from increases in human disturbances at beach and coastal areas, associated with
conversion of agricultural areas to urban uses at the proposed Hub Park at the southeast comer of Agua
Hedionda Lagoon and the farmland at the northeast comer of Batiquitos Lagoon. Nesting of snowy
plovers on ocean beaches may be precluded by intensive recreational use, which would continue with
plan implementation.
Human disturbance can interfere with normal snowy plover behavior. Disturbances to incubating
adults can leave nests exposed to extreme temperatures resulting in non-viable eggs or blowing sand
which buries the eggs. Snowy plover chicks which are separated from their attending adult as a result
of human disturbances or predators, may become more susceptible to hypothermia since young chicks
are unable to thermoregulate. It has been shown that increased human dsturbance forces piping plover
chicks (Churudrius melodius), an East coast species with habitat requirements very similar to the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 146 -
snowy plover, to expend more energy avoiding disturbances and less time foraging (Fleming et al.
1988). Frkquently-disturbed piping plover chicks fed less often and at a reduced rate with fewer chicks
surviving to 17 days in areas heavily disturbed by humans (Fleming et al. 1988). Ruhlen et al. (2003)
found that on weekends and holidays, when human visitation to snowy plover nesting habitat was
approximately five times greater than on weekdays, the rate of chick loss was approximately three
times the chick loss rate on weekdays.
The Subarea plan provides a basis for the conservation of this species and its associated habitats by
requiring the following:
1. Manage preserve areas to minimize edge effects, control non-native plants, maintain hydrology
and water quality, protect habitats from physical disturbances, and control predators. Where
opportunities arise, restore and enhance habitat in preserved areas.
Restrict activities near nesting habitat during the breeding season (April 1 through August 31).
If populations are present during the non-breeding season, implement access control measures
if warranted.
The major and critical population at Batiquitos Lagoon shall be managed by the California
Department of Fish and Game to control predators, control weed gowth on nesting areas, and
protect against detrimental edge effects from adjacent development, recreational impacts, and
other direct and indirect impacts. Incidental take of the species or occupied habitat during the
breeding season (April 1 through August 1) is prohibited except as specifically authorized on a
case-by-case basis. The long-term management plan shall address enhancement of other
potential Snowy Plover nesting areas, such as Buena Vista Lagoon, including nesting sites and
water quality.
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the western snowy plover) dependent on
estuarine habitats. These measures are intended to minimize indirect impacts to plovers and
other estuarine species.
2.
3.
4.
As a result of the measures incorporated into the Subarea Plan and the MHCP Subregional Plan, we
anticipate few indirect impacts to this species at the sites currently used for nesting. In addition,
management will begin initially for all of the breeding locahty points for this species since it occurs in
the lagoons which will be managed by California Department of Fish and Game. However, indirect
effects are expected to continue to possibly preclude snowy plovers from nesting on ocean beaches
which are not in the FPA and will not be managed as part of the MHCP.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this species
as described above. No direct impacts are expected from the MHCP Subregional Plan or City’s
Subarea Plan due to 100 percent conservation at the coastal lagoons and because the h4HCP will not
allow any take of individuals or nests of this species. This species will benefit from the no-net-loss of
wetlands, wetland buffer and critical locations policies. The MHCP Subregional Plan and City’s
Subarea Plan will provide monitoring and management of this species that will detect and minimize
negative impacts that are affecting western snowy plovers. Additionally, this species may benefit from
the connected preserve system that will be managed and monitored in the City and throughout the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 147
MHCP in perpetuity. This Preserve will be adaptively managed, per the measures included in the
MHCP SGbregional Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the effects
of the proposed action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional and the City’s Subarea Plans are not likely to jeopardize the continued existence or
recovery of this species.
Amount or Extent of Take
No take of western snowy plovers will occur as a result of the MHCP Subregional and City’s Subarea
Plans due to the condition of coverage which does not allow take of individuals or nests.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 148
Stem elegans (Elegant tern)
Status of the Swies
Listing Status
The elegant tern is a California Department of Fish and Game special concern species with a CNDDB
rank of G5S1. It is characterized as a lower risk, but near-threatened species on the International
Union for Conservation of Nature and Natural Resources (IUCN) Red list. This species is not listed
under the Act, however it is on the Federal Birds of Conservation Concern list (FR 68: 6179).
Species Description
Sterna elegans is a medium-sized tern: length 3942 centimeter, mass about 260 grams. In breeding
plumage, the head has a black cap and long shaggy crest (longest of all terns). Back, scapulars, and
upper wings are bluish gray, contrasting with darker gray outer primaries. The remainder of the
plumage is white, but underparts often have a pink flush. The tail is deeply forked. Legs are black,
sometimes with splotches of yellow or orange, rarely bright red. It has a long slender bill (often
exceeding the length of the bird’s head), light yellow to reddish orange, tip often yellow or light gray,
and the base often red. The curvature of the culmen gwes the illusion of the bill drooping at the tip
(Olsen and Larsson 1995). Sexes are similar. In basic plumage, forehead and Iores become white.
Remaining black portion of the cap forms triangular facial mask beginning around eye and continuing
to nape or top of crest. The remaining plumage is similar to breeding plumage, but the bill becomes
sandy red, with a yellow tip (Olsen and Larsson 1995) prom Burness et al. 19991.
Distribution
Elegant terns formerly nested at about a dozen island and coastal mainland sites in Baja California and
in the Gulf of California, Mexico (Schaffner 1986). The 5 known extant breeding colonies are at: (1)
Isla Raza in the Gulf of California, (2) Western Salt Company, south San Diego Bay, (3) Bolsa Chica
Ecological Reserve, California, (4) Isla Montague in the Colorado River delta, Gulf of California, and
(5) Los Angeles Harbor (Burness et al. 1999). Elegant terns commonly disperse to the south and
central California coast; less frequently to Oregon, and southern Washington (Tweit and Fix 1990),
and rarely to British Columbia (Porcher 1983). Primarily coastal, but has been reported at the Salton
Sea (McCaskie 1987). They winter along the Pacific coast of Mexico, Ecuador, Peru, and Chile
(common south of Equador; local and irregular from Panama north) (Burness et al. 1999).
Habitat Afinity
Beaches and lagoon shoreline, coastal spits, estuarine sandbars, and mudflats close to bay mouths
provide roosting and nesting habitat. All nesting locations are somewhat isolated, semitropical, low,
flat, sandy, with little vegetation. Post-breeders frequent seacoasts, mudflats, bays, estuaries, and
lagoons (American Ornithologists’ Union 1983, Bumess et al. 1999). Elegant terns forage primarily in
marine habitats, also in estuaries, usually within 8 kilometers of the colony, but up to 25 kilometers
distant.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 149
Life History
Northem anchovies (Engraulis rnordax) and other schooling, top-dwelling fishes are the principal food
of adults throughout their range (Schaffner 1986). This species primarily feeds in shallow Ocean
waters beyond the turbulent breaker zone where they dive for prey (Terres 1980), but may also forage
in protected bays and lagoons (Cogswell 1977). They congregate on beaches and tidal flats when not
feeding and tend to roost hgh up on sandy beaches or tidal flats (Cogswell 1977, Terres 1980).
Breeders at the San Diego Bay colony arrive in California in March or early April, much earlier than
post-nesting visitors (Garrett and Dunn 1981, Burness et al. 1999). Some individuals court and form
pairs while still on migration while others form pair bonds in the nesting colony (Schaffner 1982).
Courtship and pair formation continues in small groups on the periphery of the colony. At San Diego
Bay, these groups (called clubs) form 2 to 3 weeks before egg-laying. Nesting begins in early April,
soon after arrival near the nesting site (Burness et al. 1999). Their nest is a shallow scrape or
depression in soft sediments; or small, oval or circular polished areas on harder sediments (Schaffner
1982, Collins et al. 1991). Both nest construction and egg laying are highly synchronized (Bwness et
al. 1999). Clutch size is generally 1; rarely 2 (Burness et al. 1999). Most eggs are apparently laid in
April (Bent 1921). The incubation period is probably about 20 days, as in other similar-sized terns.
Elegant terns will lay a second clutch only if the first clutch is destroyed early in the season (Burness et
al. 1999). Chicks are usually ambulatory a few days after hatching and may travel considerable
distances from the nest in the first or second week (Burness et al. 1999). At an average of 6 days old,
chicks congregate to form a “creche”, consisting of 10-several hundred chicks, sometimes over 100
meters from the nest site. Adult terns locate and feed their own chicks within the creche. The chicks
occupy the center of the creche, while attending adults are at the periphery. Most chicks are capable of
hop-and-glide flights at 30 days of age and capable of real flight at 35 days when they join mobs of
calling adults (Schaffner 1982). In late summer, dependent juveniles follow their foraging parents,
begging as soon as the parent catches a fish. As in other crested terns, juveniles are dependent for an
extraordinarily long period over 6 months.
Population Trend
This bird is an abundant summer resident in San Diego County. Elegant terns first bred north of Baja
California in 1959 on the dikes of the Westem Salt Works in south San Diego Bay. The establishment
of this colony, a 500-kilometer extension of its breeding range, followed a strong El Niiio/Southem
Oscillation year and was coincident with an increase in anchovy abundance in waters off southern
California (Schaffner 1986). A colony was established at Bolsa Chica Ecolog~cal Reserve in 1987, at
Isla Montague in 1992, and at Los Angeles Harbor in 1998. The number of breeders has increased in
California, although numbers at specific colonies fluctuates (Burness et al. 1999). The total world
population was estimated at less than 30,000 pairs of breeding birds and 5 known colonies in 1990
(Bumess et al. 1999). Isla Rasa, Gulf of California was estimated to contain 22,500 pairs (Tob6n 1992
in Verlarde et al. 1994), or 90 to 97 percent of the world population (Clapp et al. 1993). Bolsa Chica
EcologicaI Reserve in Orange County had 4,000 pairs in 1995 but little if any successful nesting in
1998 (Burness et al. 1999). At Western Salt Works in south San Diego Bay the population was
estimated to be 1,870 pairs (Horn et al. 1996). However, less than 15 pairs were recorded in 1998
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 150
(Bumess et al. 1999). In 1998 approximately 3,000 pairs nested in Los Angeles Harbor (most
individuais presumably had relocated from the Bolsa Chica colony).
Threats
hmitation of breeding to so few colonies and dependence on a single food species renders elegant
terns vulnerable to environmental variability. At Isla Raza, breeding elegant terns suffer from
predation by introduced rats and mice and are also negatively impacted by commercial egg collectors
(Burness et al. 1999). Although the Mexican government has declared Isla Raza a sanctuary,
trespassing by egg collectors, poachers, and tourists continues to disturb the terns (Clapp et al. 1993,
Bumess et al. 1999). Urban development threatens the size and quality of nesting sites and
surrounding aquatic habitats at the breeding colonies in southern California (Horn et al. 1996). Stray
dogs and cats associated with nearby development can have devastating effects on colonies of elegant
terns (Bumess et al. 1999). For example, in 1982, a pair of stray dogs destroyed part of the San Diego
Bay Colony; more than 100 mauled elegant tern chicks were found dead, and many more were missing
(Schafher 1985).
Environmental Baseline
No breeding colonies are known in the MHCP planning area. There are no known major populations
or critical areas within the MHCP, however, lagoons and beaches within the MHCP area do provide
important wintering habitats. Location points have been recorded in Carlsbad, Encinitas, and
Oceanside.
At Buena Vista Lagoon, Batiquitos Lagoon, and Aqua Hedionda Lagoon in the City of Carlsbad, the
Subarea currently provides 934 acres of estuarine and salt marsh habitat, including open water suitable
for foraging, sand and mud flats where elegant terns may loaf post-breeding, and artificial nesting areas
(created for least terns) that may provide suitable nesting habitat for elegant terns. Elegant terns are not
currently known to nest anywhere in the subarea or subregion. Elegant terns have been documented
from Buena Vista and Batiquitos lagoons. During post-breeding dispersal, large numbers of elegant
terns may use the coastal lagoons of the MHCP area. On August 18,2003, approximately 500 elegant
terns loafed on exposed mudflats at San Elijo Lagoon (John Martin, USFWS, pers. obs.). The elegant
tern nests south of the Subarea at the Salt Works in south San Diego Bay and an established colony has
recently been observed in Orange County to the north. Scientific information is otherwise lacking for
this species in general as well as population information within southern California.
Effects of the Action
Direct Effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive coverage
for this species:
1. Management will restrict activities within the preserve that could prevent the establishment of
additional elegant tern colonies at conserved coastal wetlands. Adverse activities include
human disturbance; off-road vehicle and pedestrian activity; changes in nesting substrates and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 151 -
2.
vegetative structure at suitable nesting sites; and presence of domestic animals (e.g., dogs and
cits), introduced predators (eg., red fox), or artificially enhanced populations of natural
predators (e.g., gulls, raccoons, and skunks).
Mitigation for any take of occupied breedng habitat must include enhancement of conserved
habitat to induce the initiation of new breeding colonies. This may include modification of
nesting substrate, vegetation clearing in limited areas deemed appropriate for tern nesting,
placement of tern decoys to attract prospecting terns. If a colony is established, the site will be
fenced and signed created to prohibit public access.
Direct impacts to elegant terns may result from the MHCP Subregional Plan. Although the foraging
areas in the estuarine habitat is 100 percent conserved, only 18 percent of beach habitat will be
conserved. Overall, 970 acres (96 percent) of suitable elegant tern habitat (estuarine, beach, salt pan,
and mudflat vegetation) will be conserved throughout the MHCP planning area. Impacts should be
minimized through the no-net-loss of wetlands and conditions for estuarine species policies.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve. There are no projects proposed for ths area,
however, impacts may occur in the future in the right-of-ways due to projects such as road widening
which would be beyond the control of the City. Such impacts would be analyzed and permitted under
a different mechanism than the MHCP. 339 acres of southern coastal salt marsh and freshwater marsh
vegetation communities constitute potential habitat for white-faced ibis. A small amount of additional
habitat in the lagoons are also technically not in the mapped area of the preserve, however, no projects
are planned for this area by the City and 100 percent conservation due to MHCP standards for
avoidance, minimization, and mitigation of wetland impacts assure no-net-loss of lagoon wetland
habitat. However, impacts can occur to such wetland communities as described in section 3.6 of
MHCP Volume 1. Since such impacts would need to be fully mitigated according to section 4.4.2 of
MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there could be a
temporal loss of such functions and values. The MHCP conditions for estuarine species and fact that
all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due to these
standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine, salt
marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, direct take of animal
species is expected to be minimized because any areas proposed for disturbance would be avoided
where MHCP species or nests are known or found to be present.
All of the suitable potential elegant tern breeding habitat on artificial tern nesting islands and salt pans
in the lagoons is included within the preserve. None of the sandy ocean beach habitat in the HMP area
is included within the preserve. The preserve includes nearly all of the open water in the lagoons,
which may serve as tern foraging habitat. Approximately 5.5 acres of open water in Batiquitos Lagoon
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 152 -
and 3 acres of open water in Agua Hedionda Lagoon, associated with the Interstate 5 right-of-way
would no; be included in the preserve.
Indirect Eflects
Indirect impacts have the potential to adversely affect elegant terns. These indirect impacts include
night lighting, human disturbance, depredation by domestic pets, and habitat degradation, as generally
explained and applicable in the “General Indirect Effects” section.
Estuaries and bays including eelgrass (Zosteru sp.) provide important habitat for juvenile northern
anchovy and other important prey species for elegant terns (Baird 1997). Therefore, impacts to
eelgrass beds could disrupt the foraging behavior of terns. Like most aquatic plant species eelgrass
responds to increases in turbidity and the degradation of water quality, which may result from urban
development. Development-related degradation of water quality in the surface waters and lagoons of
the Subarea may affect the productivity and health of eelgrass beds and the fish species associated with
them. In this manner, and by otherwise disrupting ecological function within lagoons, development-
related degradation of water quality may adversely affect elegant terns. Contaminants that may affect
aquatic organisms in the lagoons may be carried to the lagoon by storm water runoff from throughout
the watershed. Developed areas are sources of non-point source pollution. Development also
increases the amount of impervious surface in the watershed, increasing the velocity and volume of
storm water runoff, thus exacerbating conveyance of non-point source pollution in storm water runoff.
Therefore, development throughout Carlsbad may affect elegant terns and their lagoon habitat.
Degraded water quality may also affect visibility of tern prey. The elegant tern is a sight feeder. Even
if schools of fish utilized by elegant terns are not totally obscured, turbid water conditions could
adversely affect tern foraging behavior by obscuring individual fish.
Also, indirect impacts to the elegant tern could result from loss of roosting sites due to disturbance
from adjacent habitat development, and increases in human disturbances at beach and coastal areas.
Specifically, indxect impacts to the elegant tern could result from increases in human use of beach and
coastal areas, associated with conversion of agncultural areas to urban uses at the proposed Hub Park
at the southeast comer of Agua Hedionda Lagoon and the farmland at the northeast comer of
Batiquitos Lagoon.
The Subarea plan and MHCP requires the following measures to conserve elegant terns:
1. Manage preserved areas to minimize edge effects, control non-native plants, maintain
hydrology and water quality, protect habitats from physical disturbances, control predators, and
maintain vegetation to provide optimal conditions for breeding. Where opportunities arise,
restore and enhance habitat in preserved areas. Habitat adjacent to the lagoons will be
preserved to the maximum extent possible.
The long-term preserve management plan shall provide area-specific directives to protect
against detrimental edge effects from adjacent development, recreational impacts, and other
2.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 153
direct and indirect impacts. Incidental take of the species during the breeding season is
prbhibited except as specifically authorized on a case-by-case basis by the wildlife agencies.
The long-term management plan shall address enhancement of other potential elegant tern
nesting areas, such as Buena Vista Lagoon, including nesting sites and water quality.
Management will restrict human access in active nesting areas during the breeding season
(April 1 through September 15) by fencing and signage. Management will also control other
threats to the species, including off-road vehicle activity; changes in nesting substrates and
vegetative structure at nesting sites; inundation of colonies by high tides or freshwater; and
predation of adults and nests by domestic animals (e.g., dogs and cats), introduced predators
(e.g., red fox), or artificially enhanced populations of natural predators (e.g., gulls, raccoons,
and skunks).
Mitigation for any impacts to occupied habitat must include enhancement of habitat to induce
the initiation of new breeding colonies. This may include fencing, modification of nesting
substrate, vegetation clearing in limited areas deemed appropriate for tern nesting, placement
of tern decoys to attract prospecting terns, and creation of islands of vegetation or tile shelters
to provide cover for chicks.
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the elegant tern) dependent on estuarine
habitats. These measures are intended to minimize indirect impacts to terns and other estuarine
species. Measures include regulation of adjacent land use, recreational access, mosquito
control, noise, vehicle access, potentid pollutants, access during breeding season, camping and
picnicking; area-specific management measures including fencing, animal and plant pest
control, habitat enhancement and/or creation, trash removal, erosion control, maintenance of
tidal flushing; monitoring of covered species populations, biodiversity, habitat area, effect of
recreation on wildlife, pest animal and plant populations, use by migratory birds, and success
of restoration efforts; and development of public awareness program including public
participation in management, development of community outreach programs, and
improvement of trails and facilities to focus public access.
3.
4.
5.
In addition, management will begin initially for all of the breeding locality points for this species since
it occurs in the lagoons which will be managed by California Department of Fish and Game.
However, indirect effects are expected to continue to possibly preclude elegant tern nesting on Ocean
beaches which are not in the FFA and will not be managed as part of the MHCP.
Conclusion
We anticipate the MHCP Subregional Plan will directly and indirectly affect this species through
habitat loss. However, a majority (96 percent) of elegant tern habitat will be conserved and it should
also be protected by the no-net-loss of wetland policy. The City’s Subarea Plan is not expected to
directly affect this species since all elegant tern habitat and species points will be conserved. The
MHCP Subregonal Plan and City’s Subarea Plan will provide monitoring and management of this
species that will detect and minimize negative impacts that are affecting elegant terns. Additionally,
this species should benefit from the connected preserve system that will be managed and monitored in
the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 154 -
benefit the species. After reviewing the current status of this species, the environmental baseline for
the action’area, the effects of the proposed action, and the cumulative effects, it is the Service’s
biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to
jeopardize the continued existence or recovery of thls species.
Amount or Extent of Take
The Service anticipates that no individuals of elegant tern will be taken as a result of the City’s
Subarea Plan. This is because the City will be conserving 100 percent of the species habitat and all
three known point locations.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 155
Sterna untiZZurum browni (California least tern)
Status of the Species
Listing Status
The California least tern was federally listed as endangered on October 13, 1970 (35 FR 16047) and
State listed as endangered in California on June 27, 1971. A recovery plan was adopted in 1980,
revised September 27, 1985 (U. S. Fish and Wildlife Service 1985b) and is currently being updated.
No critical habitat has been designated for the California least tern. The California least tern is a fully
protected species under the State.
Species Description
The least tern (Sterna antiZZunun) is the smallest of all North American terns, weighing approximately
40-50 grams, with an average length of 21-23 centimeters, and a wingspan of 48-53 centimeters
(Thompson et al. 1997). Adult least terns are characterized by white underparts, light gray back and
wings, short orange legs, and a black-tipped, straight, pointed yellow bill (U.S. Fish and Wildlife
Service 1985b). Adults have a black crown and nape, and a white patch extending from the bill to the
forecrown and over the middle of the eye. The white tail is shallowly forked. Their flight is light and
buoyant, but direct, with deep, quick wingbeats. The sexes are similar. Immature birds have darker
plumage and a dark bill, and their white heads with dark eye stripes are distinctive (U.S. Fish and
Wildlife Service 1985b).
Five geographic races of least tern are described in the Americas, but descriptions are based largely on
qualitative taxonomic assessments with few specimens and limited statistical analyses used for original
descriptions (Thompson et al. 1992, Patten and Erickson 1996, Thompson et al. 1997). The California
least tern (Stem antillarum browni) cannot be reliably distinguished from other least tern subspecies
on the basis of plumage characters alone (Burleigh and Lowery 1942). California least tern (35 FR
8491 8498) and interior least tern (S. a. athalmsos) (50 FR 21784-21792) are both federally listed as
endangered.
Distribution
The breeding range of this subspecies has historically been described as extending along the Pacific
Coast from Moss Landing, Monterey County, California, to San Jose del Cabo, southern Baja
California, Mexico (American Ornithologists’ Union 1957, Grinnell and Miller 1944). However,since
1970, nesting sites have been recorded from San Francisco Bay to Bahia de San Quintin, Baja
California (US. Fish and Wildlife Service 1985b). The nesting range in California is thought to have
been widely discontinuous, with the majority of birds nesting in southern California from Santa
Barbara County south through San Diego County (U.S. Fish and Wildlife Service 1985b). Their
migration route in California is along the coast in both spring and fall. South of the Mexican border,
the migratory route is not known, but is assumed to be coastal (U.S. Fish and Wildlife Service 1985b).
In southern San Diego County, recent nesting sites are known from Mission Bay (including FAA
island, north Fiesta Island, and Mariner’s Point), San Diego Bay (including South San Diego Bay
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 156
.-
National Wildlife Refuge, Sweetwater Marsh National Wildlife Refuge, Lindbergh Field, Naval Air
Station Nbrth Island, Naval Amphibious Base Coronado, and the Chula Vista Wildlife Reserve), and
the beach areas north and south of the Tijuana aver mouth. In northern San Diego County least terns
are known to breed at the mouth of the Santa Margarita River on Camp Pendleton Marine Corps Base,
at Batiquitos Lagoon (Fancher 1992, Powell and Collier 2000), and at San Elijo Lagoon (Robert
Patton, unpubl. data).
Habitat Afinity
Unfrequented sandy beaches close to estuaries and coastal embayments have traditionally served as
nesting sites for the California least tern (Grinnell and Miller 1944, Garrett and Dunn 1981). Because
potential nesting habitat has been greatly reduced by human recreation and development, traditional
habitats have often been abandoned while human-made habitats (e.g., salt pond dikes, sand flats,
sandfills, airports, gravel rooftops, and landfills around bays and estuaries) have been colonized
(Thompson et al. 1997).
Life History
The California least tern is migratory, usually arriving in its breeding area by the last week of April and
departing again in August (Massey 1974). However, terns have been recorded in the breeding range as
early as March 13 and as late as November 24 (San Diego Natural History Museum specimen records).
Least terns are gregarious year-round, feeding and migrating in flocks of 5-20 or more. The terns flock
together before the nesting season, at night roosts during the nesting season, and at shallow-water,
freshwater, and estuarine marshes after the nesting season (Atwood and Minsky 1983, U.S. Fish and
Wildlife Service 1985b). Nesting colonies of least terns are as large as 2,000 pairs, but usually consist
of less than 25 pairs. They are more loosely colonial than other tern species; nests are sometimes so
widely spaced as to be out of sight of conspecifics (Thompson et al. 1997).
The nest of the California least tern is a simple scrape or depression in the sand and one to four eggs
are laid, usually two. There is one breeding season, from May through August (Massey and Atwood
1981), and only one brood is raised. However, the birds will renest if eggs or chicks are lost (Massey
and Atwood 198 1). Re-nesting attempts after initial failures, and 2-year-old birds nesting for the first
time, often occur from mid-June to early August (Massey and Atwood 1981). Both parents share
duties throughout nesting and chick-rearing, but the female incubates and broods chicks more than the
male (Keane 1987). Newly hatched downy chicks are capable of walking in the vicinity of the nest
(e.g., to seek shade) (Cornwell 1986). Young are capable of flight at approximately 20 days. Most
disperse from the nesting colony about 3 weeks after hatching (Thompson and Slack 1984, Atwood
and Massey 1988).
feed inexpertly for several weeks, and ultimately depart colony area in preparation for migration within
4-8 weeks of fledging. Chicks are fed by parents for several weeks after fledging (Thompson et al.
1997). Minimum breeding age is 2 years (Massey and Atwood 1981).
Recently fledged chicks intermingle with adults and chicks from other colonies,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 157 -
This species typically feeds on topsmelt, northern anchovy, and jack-smelt (Atwood and Kelly 1984),
which are’to some extent dependent on eelgrass habitats (Baird 1997). Feeding is carried out both in
the calm waters of narrow estuaries or large bays and for a short distance (i.e., usually within 3
kilometers [Atwood and Minsky 19831) off beaches in the open Ocean (Cogswell 1977). They
characteristically forage by hovering 1-10 meters above the water, then plunging headfirst into the
water to seize small fish. However, they may also catch small fish by quick dips of the bill on shallow
swoops over the water surface (Cogswell 1977).
Population Trend
The California least tern was formerly “common to abundant” (Grinnell and Miller 1944) along the
central and southern California coast, to the extent of being described as “numberless” on the beaches
of Los Angeles County (Bent 1921). Grinnell and Miller (1944), however, commented that least tern
breeding colonies were, by 1943 “few and sparsely populated, owing to the almost complete human
use of suitable beaches.” By 1970, when the species was Federally listed as an endangered species,
numbers of California least tern had declined to 600-700 breeding pairs with 26 nesting sites Pender
1974). The updated recovery plan reported between 890 and 1,299 breeding pairs in California
between 1980 and 1983. Intensive management efforts, particularly protection of foragng and nesting
areas and predator management, have allowed the California least tern to increase in abundance from
623 pairs in 1969 to an estimated 4,700 pairs in 2001. Populations in 2002 experienced a slight
decline to approximately 3,500 pairs (Fish and Wildlife Service, unpubl. data). The majority of least
tern populations are concentrated in southern California within the Counties of Los Angeles, Orange,
and San Diego.
Threats
The escalating recreational use of southern California beaches during the tern nesting season has led to
isolated, small colony sites that artificially concentrate breeding terns, putting them at risk of
depredation. Episodic losses have been attributed to cold, wet weather, extreme heat, dehydration and
starvation, unusually high surf or tides, and human disturbance. Birds nesting in areas frequented by
humans often suffer from disturbance. Humans kill eggs and chicks by stepping on them
inadvertently, by deliberately collecting eggs for food or fun, or by off-road-vehicle traffic and
earthmoving equipment (Goodrich 1982, Burger 1989, Cowgill 1989, Lingle 1993, Smith and Renken
1993, arsch 1996).
Limitation in number and restriction in size of breeding sites may exacerbate effects of predation on
least tern populations. Loss of tern chicks has been attributed to a number of predators, includmg
American kestrels (Falco sparverius), burrowing owls (Athene cunicularia), loggerhead shnkes
(Lanius ludovicianus), American crows (Corvus brachyrhynchos), common ravens (Corvus corm)
coyotes (Canis latrans), red foxes (Vulpes vulpes) house cats (Felis catus), and dogs (Canis familiaris)
(U.S. Fish and Wildlife Service 1985b).
The presence of eelgrass is important as habitat for several prey species of California least terns, such
as northern anchovy, topsmelt, and jacksmelt (Baird 1997). The abundance of these species play an
important role in the foraging habits of least terns. Therefore, impacts to eelgrass beds could disrupt
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 158
the foraging behavior of terns. Like most aquatic plant species eelgrass responds to increases in
turbid@ zkd the degradation of water quality, which may result from urban development.
Development-related degradation of water quality in the surface waters and lagoons of the Subarea
may affect the productivity and health of eelgrass beds and the fish species associated with them. In
this manner, and by otherwise disrupting ecological function within lagoons, development-related
degradation of water quality may adversely affect least terns. Degraded water quality may also affect
visibility of tern prey. The least tern is a sight feeder. Schreiber et al. (1975) believed that terns select
individual fish, even within a school. Even if schools of fish utilized by least terns are not totally
obscured, turbid water conditions could adversely affect tern foraging behavior by obscuring individual
fish. Adult least terns catch and deliver small fish to flightless young. The young begin to fly at about
20 days of age, but continue to be fed by parents and accompany parents while parents forage for some
time after fledging. Reproductive success is, therefore, closely related to the availability of undisturbed
waters with adequate supplies of appropriately sized fishes. Reduced food availability at a southern
California least tern colony site was determined to affect the reproductive success of the tern including
smaller clutch sizes, significantly lower weights of chicks, and increased levels of egg abandonment
and non-predator chick mortality (Atwood and Kelly 1984). Increased chick mortality decreases
recruitment to the breeding population. Shortages of food for adults can also be manifested in small
clutch sizes and increased levels of egg abandonment.
California least terns may also be somewhat susceptible to the expressed effects of pesticide
contamination and bioaccumulation (Boardman 1988).
Environmental Baseline
Within the MHCP planning area, California least terns have been documented at the San Luis Rey
River mouth, Buena Vista, Agua Hedionda, Batiquitos, and San Elijo lagoons. All populations are
considered critical locations and the population at Batiquitos Lagoon is also considered a major
population.
In the City of Carlsbad, Buena Vista, Agua Hedionda, and Batiquitos lagoons contain approximately
934 acres of estuarine and salt marsh habitat that support or potentially support California least tern.
However, not all of this consists of least tern habitat. Within this area, only an unquantified area of
open sand or salt pans around lagoons consist of suitable nesting habitat for the least tern. The open
water areas in the coastal lagoons may serve as tern foraging habitat. The HMP area contains
approximately 10.2 kilometers of sandy beach along the coast. However, virtually all is subject to
heavy recreational use.
Within the Subarea, least terns are currently only known to nest at Batiquitos Lagoon, where the
number of pairs has ranged between 179 and 136 between 1998 and 2000 (Patton 2002). Within the
MHCP area, least terns also nest at San Elijo Lagoon, where between 1-15 pairs nested between 1998-
2000 (Patton 2002).
Least tern population sizes in 2001 reached 2,164 nesting pairs within San Diego County. Of the
lagoons within the Subarea, Batiquitos Lagoon experiences the only nesting with 205 nesting pairs
observed in 2001(CDFG 2002). Buena Vista Lagoon has not documented nesting since 1981, when
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 159
two (2) pairs were observed (Unitt 1984), while Agua Hedionda Lagoon has had no documented
nesting. With the absence of nesting in the remaining lagoons least terns are still known to forage or
loaf within these areas.
Previous impacts to least terns may have resulted from the dredging of Agua Hedionda Lagoon. It
initially dredged in 1954 to provide a source of cooling water for San Diego Gas & Electric
Company’s Encina Power Plant. Since 1954, the outer lagoon undergone periodic maintenance
dredging, while no dredging had occurred in the middle and inner lagoons. The outer lagoon is
dredged every one to three years. In 1998 SDG&E was permitted to dredge Agua Hedionda’s middle
and inner lagoons and discharge the dredged material (spoil) on the Encina Power Plant jetty and a
borrow pit created in the lagoon. Dredging of the lagoon removes sand deposited in the outer lagoon
and may preclude formation of sand islands upon which terns could nest.
Batiquitos Lagoon has experienced extensive restoration. Restoration of this seasonal tidal waterbody
was initiated in 1994 and completed in 1996. It resulted in the continuous tidal exchange of Pacific
Ocean waters. Dredge spoils were used as beach nourishment north of the lagoon. Spoils were also
utilized to create five nesting areas for the least tern and snowy plover. Least terns regularly nest at
some of the created sites (Patton 2002). The inlet channel to Batiquitos Lagoon was also dredged in
2000 with a portion of dredged material placed on the at previously created nesting sites.
Effects of the Action
Direct Efects
The MHCP Subregional Plan requires no take of individuals or active nests, including by harassment,
for this species. In addition, management must control human access to avoid trampling or harassment
in breeding areas. The MHCP also requires the following conditions be met for a city to receive
coverage for this species:
1. Management will restrict human access in active nesting areas during the breeding season
(April 1 through September 15) by fencing and signage. Management will also control other
threats to the species, including off-road vehicle activity; changes in nesting substrates and
vegetative structure at nesting sites; inundation of colonies by high tides or freshwater; and
predation of adults and nests by domestic animals (e.g., dogs and cats), introduced predators
(e.g., red fox), or artificially enhanced populations of natural predators (e.g., gulls, raccoons,
and skunks).
Mitigation for any impacts to occupied habitat must include enhancement of habitat to induce
the initiation of new breeding colonies. This may include fencing, modification of nesting
substrate, vegetation clearing in limited areas deemed appropriate for tern nesting, placement
of tern decoys to attract prospecting terns, and creation of islands of vegetation or tile shelters
to provide cover for chicks.
The MHCP Subregional Plan will not directly impact this species because it requires no take of
individuals or nests, including by harassment, of this species. In addition, the foraging areas in
the estuarine habitat is 100 percent conserved, but only 18 percent of beach habitat will be
conserved. Overall, 970 acres (96 percent) of suitable least tern habitat (estuarine, beach, salt
pan, and mudflat vegetation) will be conserved throughout the MHCP planning area. Impacts
2.
3.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 160 -
should be minimized through the no-net-loss of wetlands and conditions for estuarine species
pdicies.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934’acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve since Caltrans and the Federal Highway
Administration is not a participant to this MHCP. Any impacts that may occur in the future in these
right-of-ways due to projects such as road widening would be analyzed and permitted under a different
mechanism than the MHCP.
A small amount of additional habitat in the lagoons are technically not in the mapped area of the
preserve, however, no projects are planned for this area by the City and 100 percent conservation due
to MHCP standards for avoidance, minimization, and mitigation of wetland impacts assure no-net-loss
of lagoon wetland habitat. However, impacts can occur to such wetland communities as described in
section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated according to
section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there
could be a temporal loss of such functions and values. The MHCP conditions for estuarine species and
fact that all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due
to these standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine,
salt marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, indirect effects will be
minimized because any areas proposed for disturbance would be avoided where MHCP species or
their nests are know or found to be present. All of the suitable California least tern nesting habitat on
artificial tern nesting islands and salt pans in the lagoons is included within the preserve. The preserve
includes nearly all of the open water in the lagoons, which may serve as tern foraging habitat. Thus,
because there will be no-net-loss of foraging area, and the quality of foraging habitat will not be
significantly degraded due to the conditions for estuarine species, no direct impacts to California least
tern are expected from implementing the MHCP nor the HMP.
Indirect Effects
Indirect impacts have the potential to cause significant adverse affects to least terns within the Subarea.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets, and
habitat degradation, as generally explained and applicable in the “General Indirect Effects” section.
Also, indirect impacts to the Least tern could result from loss of roosting sites due to disturbance from
adjacent habitat development, and increases in human disturbances at beach and coastal areas.
Specifically, indirect impacts to the least tern could result from increases in human use of beach and
coastal areas, associated with conversion of agricultural areas to urban uses at the proposed Hub Park
at the southeast corner of Agua Hedionda Lagoon and the farmland at the northeast comer of
Batiquitos Lagoon.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 161
Indirect effects to least terns may result from degradation of water quality in the lagoons.
Contamin'ants that may affect aquatic organisms (including tern prey) in the lagoons may be carried to
the lagoon by storm water runoff from throughout the watershed. Developed areas are sources of non-
point source pollution. Development also increases the amount of impervious surface in the
watershed, increasing the velocity and voIume of storm water runoff, thus exacerbating conveyance of
non-point source pollution in storm water runoff. Therefore, development throughout Carlsbad may
affect least terns and their lagoon habitat.
The Subarea and MHCP plans require the following measures to conserve California least terns:
1. The major and critical population at Batiquitos Lagoon shall be managed by the California
Department of Fish and Game to control predators, control weed growth on nesting areas, and
protect against detrimental edge effects from adjacent development, recreational impacts, and
other direct and indirect impacts. Incidental take of the species or occupied habitat during the
breeding season is prohibited except as specifically authorized on a case-by-case basis. The
long-term management plan shall address enhancement of other potential Least Tern nesting
areas, such as Buena Vista Lagoon, including nesting sites and water quality.
No take of individuals or active nests are allowed for this species.
Management will restrict human access in active nesting areas during the breeding season
(April 1 through September 15) by fencing and signage. Management will also control other
threats to the species, including off-road vehcle activity; changes in nesting substrates and
vegetative structure at nesting sites; inundation of colonies by high tides or freshwater; and
predation of adults and nests by domestic animals (e.g., dogs and cats), introduced predators
(e.g., red fox), or artificially enhanced populations of natural predators (e.g., gulls, raccoons,
and skunks).
Mitigation for any impacts to occupied habitat must include enhancement of habitat to induce
the initiation of new breeding colonies. This may include
fencing, modification of nesting substrate, vegetation clearing in limited areas
deemed appropriate for tern nesting, placement of tern decoys to attract
prospecting terns, and creation of islands of vegetation or tile shelters to provide
cover for chicks.
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the California least tern) dependent on
estuarine habitats. These measures are intended to minimize indirect impacts to terns and other
estuarine species. Measures include regulation of adjacent land use, recreational access,
mosquito control, noise, vehicle access, potential pollutants, access during breeding season,
camping and picnicking; area-specific management measures including fencing, animal and
plant pest control, habitat enhancement and/or creation, trash removal, erosion control,
maintenance of tidal flushing; monitoring of covered species populations, biodiversity, habitat
area, effect of recreation on wildlife, pest animal and plant populations, use by migratory birds,
and success of restoration efforts; and development of public awareness program including
public participation in management, development of community outreach programs, and
improvement of trails and facilities to focus public access.
2.
3.
4.
5.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 162 -
In addition, management will begin initially for all of the locality points for this species since it occurs
in the lagbons which will be managed by California Department of Fish and Game. However, indirect
effects are expected to continue to possibly preclude California least terns from nesting on ocean
beaches which are not in the FPA and will not be managed as part of the MHCP.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will indirectly affect this species
as described above. No &rat impacts are expected from the MHCP Subregional Plan or City’s
Subarea Plan due to 100 percent conservation at the coastal lagoons and because direct impacts to
individuals, nests, and young will be avoided. This species will benefit from the no-net-loss of
wetlands, wetland buffer and critical locations policies. The MHCP Subregional Plan and City’s
Subarea Plan will provide monitoring and management of this species that will detect and minimize
negative impacts that are affecting California least terns. Additionally, this species will benefit from a
foraging aspect by the connected preserve system that will be managed and monitored in the City and
throughout the MHCP in perpetuity. This Preserve will be adaptively managed, per the measures
included in the MHCP Subregional Plan, which will further reduce the indirect effects and benefit the
species. After reviewing the current status of this species, the environmental baseline for the action
area, the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional and the City’s Subarea Plans are not likely to jeopardize the
continued existence or recovery of this species.
Amount or Extent of Take
No take of California least tern individuals or nests will occur as a result of the MHCP Subregional
and City’s Subarea Plans due to the the MHCP condition of coverage, no-net-loss of wetland policy,
protection of all tern nesting areas, and conditions for estuarine species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 163
Empidonax traillii extimus (Southwestern willow flycatcher)
Status of the SDecies
Listing Status
The southwestern willow flycatcher was federally listed as endangered on February 27, 1995 (60 FR
10694). Additionally, the California Department of Fish and Game lists this species as endangered.
Critical habitat was designated on July 22, 1997 (US. Fish and Wildlife Service 1997). A correction
notice was published in the Federal Register on August 20, 1997 to clarify the lateral extent of the
designation (U.S. Fish and Wildlife Service 1997). However, on May 11,2001, the 10” circuit court
of appeals set aside designated critical habitat in those states under the 10” circuit’s jurisdiction (New
Mexico). The Service decided to set aside critical habitat designated for the southwestern willow
flycatcher in all other states (California, and Arizona) until the economic analysis is re-assessed. The
Service published a proposed critical habitat designation for southwestern willow flycatcher on
October 12,2004 (69 FR 60706)..
Species Description
Empidonax traillii extimus, a relatively small, insectivorous songbird, is approximately 15 centimeters
(5.75 in) in length. Both sexes of E. t. extimus have graysh-green back and wings, whitish throats,
light gray-olive breasts, and pale, yellowish bellies. The song is a sneezy “fitz-bew” or “fitz-a-bew”
and the typical call is a breathy “whit” (e.g., Unitt 1987). E. t. extimus is a recognized subspecies of
the willow flycatcher (Empidonax traillii). Although previously considered conspecific with the alder
flycatcher (Empidonax alnorum), E. traillii is distinguishable from that species by morphology
(Aldrich 1951), song type, habitat use, structure and placement of nests (Aldrich 1953), eggs
(Walkinshaw 1966), ecological separation (Barlow and MacGillivray 1983), and genetic distinctness
(Seutin and Simon 1988). In turn, E. t. extimus is one of five subspecies of the willow flycatcher
currently recognized (Hubbard 1987, Unitt 1987, Browning 1993). The willow flycatcher subspecies
are distinguished primarily by differences in color and morphology. Although the subspecific
differences in color have been termed “minor” (Unitt 1987), P.E. Lehman (recognized expert field
biologist, pers. comm.) has indicated that E. t. extimus in California is distinguishable in the field from
other forms of willow flycatchers that might be present (in migration) within the breeding range of the
former. Unitt (1987) and Browning (1993) concluded that E. t. extimus is paler than other willow
flycatcher subspecies. Preliminary data also suggest that the song dialect of E. t. extimus is
distinguishable from other willow flycatchers.
Distribution
The breeding range of the flycatcher includes most of the southwestern United States (Unitt 1987,
Browning 1993) with data from 1993 to 2001 indicating that flycatcher breedmg territories ranged
from Arizona (36 percent), California and New Mexico (26 percent each), Nevada (7 percent),
Colorado (4 percent), and Utah (1 percent) (Sogge et al. 2003). Past records of breeding in Mexico are
few and confined to extreme northern Baja California and Sonora (Howell and Webb 1995).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 164
Flycatchers winter in Mexico, Central America, and northern South America (Howell and Webb
1995).
Habitat Afinity
The southwestern willow flycatcher is restricted to willow-dominated riparian habitats, especially areas
with abundant large trees, frequently in close proximity (i.e., seldom farther than a few dozen meters)
to surface water or saturated soil (Sogge and Marshall 2000). Riparian habitat provides both breeding
and foraging habitat for the species. The flycatcher nests in thickets of trees and shrubs approximately
4 to 7 meters (13 to 23 ft) or more in height with dense foliage from approximately 0 to 4 meters (0 to
13 ft) above ground. The nest site plant community is typically even-aged, structurally homogeneous
and dense (Brown 1988, Sedgewick and Knopf 1992). This species usually nests in the upright fork of
a shrub but occasionally nests on horizontal limbs within trees and shrubs (Terres 1980). Historically,
the willow flycatcher nested primarily in willows and mule fat with a scattered overstory of
cottonwood (Grinnell and Miller 1944). Following more recent changes in riparian plant communities
in the region, the species still nests in willows where available but is also known to nest in thickets
dominated by tamarisk and Russian olive (Brown 1988). Typically, sites selected as song perches by
male willow flycatchers show higher variability in shrub size than do nest sites and often include large
central shrubs. Fragmented riparian zones with large distances between willow patches and individual
willow plants are not selected for either nesting or singing (Sedgewick and Knopf 1992). Flycatchers
are generally not found nesting in narrow strips of riparian vegetation less than approximately 33 feet
wide (Sogge and Tibbetts 1994, Sogge and Marshall 2000). Flycatchers are site tenacious, but have
beenknown to disperse on average 25 miles within a dramage (Greg Beaty, USFWS, pers. comm.
2004). Stuhes have shown that movements within drainages are most common, with a mean &stance
moved of 8.7 miles and that between-year movements between drainages may be less common (US.
Fish and Wildlife Service 2002). However, this could be a byproduct of the study locations.
Migrating willow flycatchers use habitats similar to breeding flycatchers, but will also use desert
washes, oases, and open canyon woodlands near watercourses (Small 1994).
Life History
The southwestern willow flycatcher is a diurnally active species that begins singing at a predawn hour
while within the territory (San Diego Natural History Museum 1995). The flycatcher is an insectivore
that forages within and above dense riparian vegetation, taking insects on the wing or gleaning them
from foliage (U.S. Fish and Wildlife Service 1995). This species also forages in areas adjacent to nest
sites which may be more open (US. Fish and Wildlife Service 1995).
Males typically arrive in southern California at the end of April and females arrive approximately one
week later. The southwestern willow flycatcher has a home range that is larger than the defended
territory. This species initiates territorial defense in late May. Territory size varies from 0.59 to 1.33
acres (0.24 to 0.45 ha). Adults depart from the breeding territory in mid-August to early September
(San Diego Natural History Museum 1995). The migration routes and destination of the southwestern
willow flycatcher are not well understood. The species has been reported to sing and defend winter
territories in Mexico and Central America. The southwestern willow flycatcher most likely winters in
Mexico, Central America, and perhaps northern South America, however, the habitats it uses on the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 165 -
winteringpounds are unknown (U.S. Fish and Wildlife Service 1995). Two individual southwestern
willow flycatchers banded on breeding territories have been recaptured in Costa Rica (Kronkiewicz
and Sogge 2001).
Southwestern willow flycatchers typically raise one brood per year (U.S. Fish and Wildlife Service
1995). The clutch size ranges from two to five; the average clutch size is 3.4 eggs in coastal southern
California. These species usually have a monogamous mating system within one nesting season
although not all territorial males are mated (San Diego Natural History Museum 1995). The
southwestern willow flycatcher fledgling leaves the nest at age 12-15 days in early July (U.S. Fish and
Wildlife Service 1995) and usually disperses from the natal temtory at age 26-30 days. About 25
percent of adults return to their territory from the previous year and at least 20 percent of juveniles
return to the natal area which is usually two to four kilometers from the natal territory. Adults usually
depart from their breeding territory between 12 August and 4 September (San Diego Natural History
Museum 1995).
Population Trend
Although the breeding range extends through six states, Kus and Sogge (2003) noted that southwestern
willow flycatchers have declined to the point of near extinction as urbanization and burgeoning human
populations have resulted in widespread loss and degradation of riparian habitat. In California, there
has been a 95 percent reduction of riparian habitat over the last century and flycatchers are now absent
as a breeding species from the Central Valley of California, where they were once common (Harris et
al. 1987). Flycatchers have been dramatically reduced in number along the lower Colorado River,
which historically probably supported one of the largest flycatcher populations in the Southwest (Unitt
1987).
Sogge et al. (2003) reported only 986 territories located among 221 sites, rangewide within the United
States using data from 1993 to 2001, many of which consisted of unpaired males. Over the range of
the species, most (82 percent) breeding sites are small, both in terms of population size (five or fewer
territories) and habitat patch size (Sogge et al. 2003). Only 18 percent of the sites rangewide are over
5 territories. Seven of these sites (populations) consist of 20 or more territories and only two sites
have 50 or more territories, one of which is the upper San Luis Rey River (near Lake Henshaw) in San
Diego County, which is outside of the project area and action area (U.S. Fish and Wildlife Service,
unpub. data). Small breeding sites are vulnerable to extirpation; 61 of the 65 sites from which
flycatchers were extirpated since 1993 were composed of five or fewer territories. Even the "larger"
sites of 50 or more territories are vulnerable to catastrophic events (e.g., fire, disease, or floods) and
flood control/water supply projects.
Threats
The major threats to the species are the destruction, modification, or curtailment of its habitat and nest
parasitism by the brown-headed cowbird (U.S. Fish and Wildlife Service 1995). Changes in riparian
plant communities have resulted in the degradation and elimination of nesting habitat for the willow
flycatcher which has reduced the range, dstribution, and population size of this species (U.S. Fish and
Wildlife Service 1995). Loss and modification of southwestern riparian habitats has occurred from
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 166
urban and agricultural development, water diversion and impoundment, channelization, livestock
grazing, off-road vehicle and other recreational uses, and hydrological changes resulting from these
and other land uses. It is estimated that 91 percent of historic riparian habitat has been lost in
California due to widespread destruction.
In October and November of 2003, southern California experienced significant wildfire activity. The
fires were distinguishable into 15 areas and burned a total of approximately 743,439 acres in Los
Angeles, hverside and San Bemardino, San Diego, and Ventura Counties.
It is unclear how much habitat occupied by least Bell’s vireo and southwestern willow flycatcher
burned in the recent fires because our location data is biased to areas with proposed projects (those
where surveys were necessary), could represent duplicative data, and/or could be mapped as a large
polygon without the details of number of individual birds. However, 1 11,725 acres of riparian habitat
exist within Los Angeles, Riverside and San Bernardino, San Diego, and Ventura Counties and the
fires bumed 5,668 acres (5 percent) of this riparian habitat. The most significant impacts occurred in
San Diego (3,186 acres), San Bemardino (1,304 acres), and Ventura (1,116 acres) Counties due to the
Cedar, Old, and Simi fires. For example, the Cedar fire burned 2,314 acres of riparian habitat in San
Diego County.
It is assumed that no individual vireos or flycatchers were harmed directly by these fires since the birds
are migratory and were not in the areas that burned when the fires occurred. The 2004 nesting season
would substantially be adversely affected by the temporal loss of at least 1,104 acres of suitable habitat.
Four. of the fifteen fires burned 1,104 acres of least Bell’s vireo critical habitat, which represents
approximately 3 percent of all critical habitat for the least Bell’s vireo. The Verdale and Simi fires
burned approximately 427 acres of critical habitat unit 2. This represents 10 percent of critical habitat
-within this unit. The Cedar fire burned approximately 63 acres of critical habitat unit 7, which
represents 7 percent of critical habitat within this unit. The OtayMne fire burned approximately 614
acres of critical habitat unit 9, which represents 96 percent of critical habitat within this unit.
It is expected that these areas will recover and again provide suitable habitat for vireo or flycatcher,
albeit a longer process to become suitable flycatcher habitat. However, the degree to which this
disturbance will increase non-native invasive wetland species such as Arundo and tamarisk is
unknown, but should the fires result in more Arundo and/or tamarisk in these areas, there could be a
net loss of suitable habitat until a restoration program is initiated and successful.
Considerable threats to flycatcher habitat in the lower San Luis Rey River persist. The largest most
immediate threat is flood control operation and maintenance activities in the flood control portion of
the channel. Such activities could significantly impact and degrade the riparian vegetation to the point
that flycatchers would not persist nesting in the area. Other ongoing threats include large homeless
encampments (which have been known to result in fires and the direct destruction of vegetation), the
presence of exotic vegetation including Arundu donax, natural disturbance (e.g., fires or floods),
groundwater pumping projects, and illegal fills. However, these threats to the San Luis Rey River are
not unique and are an existing problem to the survival and recovery of the flycatcher throughout its
range.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 167
Critical Habitat
The specific biological and physical features, otherwise referred to as the primary constituent elements,
essential to the conservation of the Southwestern willow flycatcher are: (1) Nesting habitat with trees
and shrubs that include, but are not limited to, willow species and boxelder; (2) Dense riparian
vegetation with thickets of trees and shrubs ranging in height from 6 to 98 feet with lower-stature
thickets of (6 through 13 feet tall) found at higher elevation riparian forests and tall-stature thickets at
found at middle- and lower- elevation riparian forests; (3) Areas of dense riparian foliage at least from
the ground level up to approximately 13 feet above ground or dense foliage only at the shrub level, or
as a low, dense tree canopy; (4) Sites for nesting that contain a dense tree andor shrub canopy (the
amount of cover provided by tree and shrub branches measured from the ground) (i.e. a tree or shrub
canopy with densities ranging from 50 percent to 100 percent); (5) Dense patches of riparian forests
that are interspersed with small openings of open water or marsh or shorter/sparser vegetation, that
creates a mosaic that is not uniformly dense. Patch size may be as small as 0.25 acres or as large as 175
acres; and (6) A variety of insect prey populations, including but not limited to, wasps and bees
(Hymenoptera); flies (Diptera); beetles (Coleoptera); butterflies/moths and caterpillars (Lepidoptera);
and spittlebugs (Homoptera).
The following Recovery Units are proposed as critical habitat for the flycatcher: 1) coastal California,
2) Basin and Mojave, 3) lower Colorado River, 4) Gila, and 5) Rio Grande. There are 21 management
units associated with these five recovery units. The Service proposed stream segments in 21
Management Units found in the 5 Recovery Units named above as critical habitat for the southwestern
willow flycatcher. These stream segments occur in southern CA, southern NV, southwestern UT, AZ,
NM, and south-central CO.
In the proposed critical habitat rule for southwestern willow flycatcher, the Service stated that there
were areas, due to the wide diversity and condition of habitat across the birds range and complexity of
the flycatchers' needs, where it was necessary to consider other factors. The other factors included: (1)
The unique nature of the Coastal California Recovery Unit because of the high connectivity across the
entire Recovery Unit and fragmented nature of the habitat; (2) management units where habitat is
limited; and (3) key migratory habitat. In these instances, the Service relied on Recovery Plan
recommendations and conservation goals, habitat needs of the flycatcher, as well as expert opinion.
The Service further states in the propose rule that unlike the other Recovery Units in the flycatcher's
range, flycatcher populations in California exist on a greater number of streams, and are almost all
located in close proximity to one another. Because of this, the selection of stream segments in
California was further scrutinized to determine which areas provided those locations essential for the
flycatcher and possessing the greatest degree of stability. In all four Management Units, the Service
selected the dominant streams with the greatest number of territories (Santa Ynez, Santa Ana, Santa
Margarita and San Luis Rey Rivers) in addition to many other stream segments to allow for population
connectivity, metapopulation stability, growth, dynamic river processes, and protection against
catastrophic loss.
Recovery Plan
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 168
The Service published a final Recovery Plan for the Southwestern Willow Flycatcher on
March 5, i002, which identifies the protection, restoration, and creation of habitat as necessary to
conserve this species. The Plan specifically identifies 6 Recovery Units and 32 Management Units that
should be managed to meet these objectives in a manner sufficient to promote stable or increasing
flycatcher populations. Each Recovery Unit is expected to serve as a metapopulation for the
flycatcher. In functioning metapopulations, increases or decreases in one population may affect other
populations. Thus, it is important to meet and maintain recovery objectives in each Recovery and
Management Unit, each of which may influence adjacent units (U.S. Fish and Wildlife Service 2002).
The Coastal California Recovery Unit, which includes the San Luis Rey River, extends across 10
southern California counties and represented 19 percent of the known flycatcher territories rangewide
from 1993 and 2001 (Sogge et al. 2002). Flycatcher populations in California are small, widely
isolated with very high percentages of unpaired males and have between only 1 and 5 territories for 90
percent of the sites (Sogge et al. 2003). There are only two relatively "large" populations within the
Coastal California Recovery Unit: the lower Santa Margarita River (17 to 18 territories annually from
1999 to 2001) and the upper San Luis Rey River (46 to 50 territories annually from 1999 to 2001)
(Kus et al. 2003). However, the Santa Margarita River population has not substantially increased over
the years even though riparian habitat has increased. In looking at the entire San Luis Rey River, it has
the largest population in California and is the only area in the State experiencing a recent increase in
numbers of breeding flycatchers.
A Population Viability Analysis (PVA) was conducted as part of the Recovery Plan for the flycatcher.
The PVA found that metapopulations appear to be the most stable and secure in those areas where a
largenumber of sites of substantial size are highly connected. There are only three such areas
throughout the species' range that meet this criteria: Coastal California, Gila, and Rio Grande. In
addition, the PVA found that the greatest benefit within a metapopulation should occur if sites are less
than 15 lun apart, each with 10 to 25 territories. Sites less than 15 km apart assure a high likelihood of
connectivity. Once a threshold of about 25 territoriedsites is reached, the benefit of increasing the
number of birds diminishes. This risk-spreading strategy reduces the likelihood that catastrophic
events (e.g. fire, flood, disease) will negatively impact all sites (U.S. Fish and Wildlife Service 2002).
Such a strategy may be even more important with the unknown risk from infectious diseases such as
West Nile Virus.
Within the Coastal California Recovery Unit, northern San Diego County is one of two areas that has
the potential to support a metapopulation, as described above. There are three larger populations: the
lower Santa Margarita River (-18 pairs); the upper San Luis Rey River (-50 pairs); and the lower San
Luis Rey River (-12 pairs). In addition there are several smaller populations within the area. These
populations are relatively close to each other: the lower reaches of the San Luis Rey River and the
Santa Margarita River are less than 15 km apart and each of them is approximately 20-30 km from the
upper San Luis Rey population. Limited data from banding studies on the lower San Luis Rey River
and Santa Margarita River within Marine Corps Base Camp Pendleton suggest dispersal of flycatchers
does occur at least to a limited extent due to their close proximity (Barbara Kus USGS pers. com.
2004).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 169 -
Because of this, the Recovery Plan identifies the San Luis Rey River as a specific river reach where
recovery ifforts should be focused. Within the action area (the lower San Luis Rey River), a growing
population of flycatchers exists (see attached figure). There were 3 known territories in 2000, 8 known
territories in 2001, 10 known territories in 2002, and approximately 10 to 13 territories of flycatchers in
2003. They are predominately located near Whalen Lake and Guajome Lake. However, others have
been identified near the confluence of the San Luis Rey River and Moosa Creek and near agriculture
ponds and water that has ponded in excavation pits within the river.
The Recovery Plan identifies guidelines that should be applied to projects to ensure recovery of the
flycatcher. These guidelines include preventing the loss of flycatcher habitat, however, if such
temporary impacts, permanent loss, or degradation is imminent, the guidelines recommend habitat
replacement, permanent protection, and management within the same Management Unit. It also states
that loss of flycatcher habitat should be replaced with creation of habitat at a relatively high ratio since
there is a high degree of uncertainty as to whether flycatchers will colonize created habitat. The
Recovery Plan also states that cowbird trapping should not be used to offset actions that may result in
loss, fragmentation, or modification of occupied or potential habitat. In addition, recent studies show
that cowbird trapping has a much less significant benefit to flycatcher productivity when compared to
vireo productivity in southern California (B. Kus, USGS, pers. corn., 2004).
Environmental Baseline
The MHCP identifies critical locations for flycatcher along the San Luis Rey River near and upstream
from Guajome Lake and on Pilgrim Creek near Foss Lake. Within the portion of the San Luis Rey
River within the MHCP planning area, suitable nesting habitat for the flycatcher is limited to a few
areas due to the lack of open water and large blocks of mature riparian habitat. These areas consist of
riparian vegetation in proximity to Whelan Lake and the perennial water near surrounding 1-5 of the
San Luis Rey River, Guajome Lake, and in the upper San Luis Rey River (i.e., below Lake Henshaw
Dam and above the Escondido Diversion Canal) where water flows year-round. Foss Lake has
potential to provide such habitat but for unknown reasons has not been known to be used by nesting
flycatchers. Pilgrim Creek has limited potential to provide habitat for flycatchers because it is dry and
surrounded by development. Scattered (probably non-breeding) observations have been recorded in
other riparian areas (e.g., Macario Canyon in Carlsbad). It is likely that small numbers of flycatcher
move through the MHCP planning area, including the City, during spring and fall migration.
Flycatchers were observed nesting in the flood control portion of the San Luis Rey River in 1999,
however, flycatchers are difficult to identify except during a small window in the spring when they
vocalize. Therefore they may have been present in the lower San Luis Rey River, but unobserved prior
to 1999. Focused survey efforts for the flycatcher detected a total of five individuals, but no evidence
of breeding activity within the flood control channel. Although this area is a flood control channel,
maintenance of the channel has not occurred to date. During the 2000 breeding season, a total of nine
flycatchers were observed, within the flood control channel, including five confirmed resident
flycatchers and four migradtransient individuals of unknown subspecies. The five resident
flycatchers consisted of two breeding pairs and one single male, all located near Whelan Lake. In
2002, two nesting pairs were again confirmed in approximately the same territories near Whelan Lake
within the Corps flood control channel. Upstream of these two pairs, within the action area, four
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 170 -
territories ,were identified near Guajome Lake; two territories were identified within the San Luis Rey
River around the confluence with Moosa Creek; and two territories were identified in the San Luis Rey
River approximately 2 miles upstream of the 1-15. In 2003, within the Corps flood control channel,
one flycatcher pair moved upstream into the active channel while a second pair remained near Whelan
Lake, on the edge of the active channel. A third male was observed within the active channel, but its
breeding status was unknown. Upstream within the action area, in 2003, one territory was mapped at
Guajome Lake and two in the San Luis Rey hver near the agricultural pond just east of the 1-15.
All of the above territories are considered as one population of flycatchers that range currently from 10
to 13 flycatcher territories due to their proximity within 25 miles of one another. This population is
considered separate from the population of flycatchers near Lake Henshaw. Although the locations in
the lower San Luis Rey River are spread out, the core population is associated with permanent water
sources and large wide mature riparian vegetation within the San Luis Rey River near Whalen Lake
and Guajome Lake.
Within the City, the following areas are likely to provide suitable habitat (i.e., with abundant mature
willows and surface water in summer) for Southwestern willow flycatchers: 1) the Sherman property
along Buena Vista Creek, 2) the City’s proposed Lake Calavera mitigation bank, 3) a State-owned area
of riparian forest northeast of the upper end of Agua Hedionda Lagoon, and 4) the riparian forest along
Encinitas Creek, in Green Valley. Presently, there are no known populations of flycatchers in the
Subarea, however there have been a few historical sightings southeast of Aqua Hedionda, north of
Palomar Airport Road.
The MHCP planning area is within the coastal California recovery unit for proposed critical habitat
and solely within the San Diego management unit of this recovery unit. There are approximately 895.8
acres of flycatcher critical habitat in the MHCP planning area. More specifically, all of the critical
habitat is within the San Luis Rey River in the City of Oceanside. The proposed critical habitat in the
MHCP planning area is predominantly high quality flycatcher habitat used by flycatchers for foraging
and dispersal. A few of the proposed critical habitat areas are occupied by flycatchers. The quality of
the habitat is high mostly due to the lack of flood control maintenance activity within the San Luis Rey
River flood control channel. However, ongoing threats persist as described above in the threats section
of this evaluation. The longest two stream segments the Service is proposing (San Luis Rey and Santa
Margarita Rivers) as critical habitat also contain the largest numbers of flycatcher territories in the San
Diego Management Unit. There is no critical habitat for the flycatcher designated within the City’s
planning area.
Effects of the Action
Direct Effects
No direct impacts to flycatcher nests, eggs, or young are expected, from the MHCP Subregional Plan
and the City’s subarea plan, since the MHCP requires the following condition for coverage: Projects
shall to the maximum extent practicable avoid impacts during the breeding season of the flycatcher
(May 1 to September 15). Projects that cannot be conducted without placing equipment or personnel
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 171 -
in or adjacent to sensitive habitats shall be timed to ensure that habitat is removed prior to the initiation
of the brekding season.
Direct impacts to flycatchers are expected to be minimal since of the 2,665 acres of riparian habitat in
the MHCP planning area, 1,996 acres (75 percent) are within the FPA. In addition, the MHCP has
standards for avoidance, minimization, and mitigation of wetland impacts to assure no-net-loss of
wetlands within the planning area. However, impacts can occur to such wetland communities as
described in section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated
according to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP,
although there could be a temporal loss of such functions and values. The MHCP also conserves all
major populations, critical areas, and point localities of flycatchers. However, the flood control
operation and maintenance activities in the San Luis Rey River could adversely affect such areas. If
such impacts occur, the effects of the MHCP and City’s subarea plan would need to be reanalyzed with
a new species baseline.
The FPA in the City conserves 494 acres (86 percent) of riparian vegetation and 25 acres (86 percent)
of oak woodland. Therefore, it can be anticipated that 2 acres (9 percent) of oak woodland and 80
acres (14 percent) of riparian could be impacted as a result of this plan. However, as stated above,
mitigation will occur to ensure no-net-loss of wetland function and value. Of the four areas listed
above with good potential to support flycatchers in Carlsbad in the future, all except the Sherman
property are included in the preserve. The Sherman property is a Standards Area in the HMP.
Standards for development within Local Facilities Management Zone 25 (which includes the Sherman
property) include:
“Conservation of 75 percent of the Sherman property is required to provide adequate
connectivity within the regional gnatcatcher corridor. Align future Marron Road to minimize
impacts to sensitive biological resources and disruption of wildlife movement. Conserve
wetland habitats and set development back at least 100 feet .... Conserve and enhance riparian
vegetation along Buena Vista Creek with 200-foot buffers supporting natural vegetation
between wetland habitats and development. Prohibit fill or development within the existing
100 year flood plain except where required for Circulation Element roads, Drainage Master
Plan facilities, or other essential public infrastructure. Use sensitive design of any road or
utility crossing of Buena Vista Creek.”
A biological constraints analysis for the Sherman property (Pacific Southwest Biological Services
2000) indicates that the site supports 50.02 acres (37.3 percent of the site) of southern arroyo willow
riparian forest. The zone-specific standards above would allow development of up to 33.5 acres (66.9
percent of the potential flycatcher habitat on site) of circulation element roads, drainage master plan
facilities, or other essential public infrastructure within potential flycatcher habitat. Though the City’s
no-net loss of wetlands policy ensures that riparian forest, riparian woodland, and riparian scrub
habitats will be replaced if impacted in the plan area, temporal loss of habitat, and degradation of
habitat quality are possible.
Zndirect Eflects
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 172 -
Indirect impacts are anticipated with the implementation of the MHCP Subregional Plan and the City’s
subarea pian, and have the potential to cause significant adverse effects to the flycatchers within the
action area. These indirect impacts include habitat fragmentation, edge effects, noise effects,
disruption of the natural fire regime, changes in hydrology from adjacent development, increased
lighting, and the proliferation of exotic species, as generally explained and applicable in the “General
Indirect Effects” section.
Specifically, indirect impacts to the flycatcher could result from the degradation of riparian habitats,
including increases in adverse edge effects (such as cowbird nest parasitism) and changes in the
hydrology or water quality. In addition, establishment of Marron Road, the Rancho del Or0
interchange, or other circulation element roads near potential flycatcher habitat would increase the
potential for traffic-related mortality of flycatchers.
The MHCP Subregional Plan requires a basis for the conservation of this species and its associated
habitats by requiring the following conditions be met before a City could receive coverage:
1. As part of the project review process (e.g. CEQA) for individual projects within the MHCP
area, a qualified biologist possessing a section 10(a)l(A) research permit for this species must
survey all areas containing suitable habitat (riparian woodlands and forests) using approved
survey protocols. Surveys shall be conducted when impacts could occur as a result of indirect
impacts by placement of the project in or adjacent to potential habitat or through creation of
suitable conditions for brown-headed cowbirds (e.g., agricultural fields, livestock presence,
woodland parks, roadsides). Surveys shall occur prior to any proposed impact regardless of
location inside or outside of the FFA.
Nesting southwestern willow flycatchers shall be treated consistent with the Critical Population
Policy (Appendix D) and impacts totally avoided. Although southwestern willow flycatcher is
not an MHCP Narrow Endemic, wintering localities and confirmed vagrants shall be treated
consistent with the Narrow Endemics Policy (Appendix D), including the following: (a)
maximum avoidance of impacts, to the degree feasible while maintaining reasonable use of the
property; (b) for unavoidable impacts, species-specific mitigation designed to minimize
adverse effects to species viability and to contribute to species recovery; and (c) no more than 5
percent gross cumulative loss of suitable habitat inside the FPA or 20 percent gross cumulative
loss outside the FPA.
Occupied habitat within the FPA shall be managed to restrict activities that could degrade
willow flycatcher habitat, including livestock grazing, human disturbance, clearing or alteration
of riparian vegetation, brown-headed cowbird parasitism, and insufficient water levels leading
to loss of riparian habitat and surface water. Area-specific management directives shall include
measures to provide appropriate successional habitat, cowbird control, and specific measures
to protect against detrimental edge effects, and will remove invasive exotic species (eg.
Arundo donax). Human access to flycatcher-occupied habitat will be restricted during the
breeding season (May 1 - September 15) except for qualified researchers or land managers
performing essential preserve management, monitoring, or research functions.
Projects having direct or indirect impacts to the southwestern willow flycatcher shall adhere to
the following measures to avoid or reduce impacts:
2.
3.
4.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 173 -
a. The removal of native vegetation and habitat shall be avoided and minimized to the
maximum extent practicable. Determination of adequate avoidance and minimization
of impacts shall be consistent with Sections 3.6 and 3.7 of the MHCP Plan. Deviations
from these guidelines shall require written concurrence of USFWS and CDFG. For
temporary impacts, the work site shall be returned to preexisting contours and
revegetated with appropriate native species. All revegetation for temporary and
permanent impacts shall occur at the rations specified in Section 4.3 of the MHCP
plan. Revegetation specifications shall ensure creation and restoration of riparian
woodland vegetation to quality that eventually is expected to support nesting
Southwestern willow flycatchers, in the opinion of experts on this species, recognizing
that it may take decades to achieve this state. All revegetation plans shall be prepared
and implemented consistent with Appendix C (Revegetation Guidelines) and shall
require written concurrence of USFWS and CDFG. If written objections are not
provided by the wildlife agencies within 30 days of receipt of written request for
concurrence by the local jurisdiction, then the deviation may proceed as approved by
the local agency. The wildlife agencies shall provide written comments specifying
wildlife agency concerns.
Projects shall be carried out consistent with Appendix B of the MHCP Volume 2
(Standard Best Management Practices) .
Projects shall to the maximum extent practicable avoid impacts during the breeding
season of the Flycatcher (May 1 to September 15). Projects that cannot be conducted
without placing equipment or personnel in or adjacent to sensitive habitats shall be
timed to ensure that habitat is removed prior to the initiation of the breeding season.
Construction noise levels at the riparian canopy edge shall be kept below 60 dBA Leq
(measured as Equivalent Sound Level) from 5 a.m. to 11 a.m. during the peak nesting
period of March 15 to July 15. For the balance of the dayheason, the noise levels shall
not exceed 60 decibels, averaged over a l-hour period on an A-weighted decibel (&A)
(i.e., 1 hour Leq/dBA). Noise levels shall be monitored, and monitoring reports shall
be provided to the jurisdictional city, USFWS, and CDFG. Noise levels in excess of
this threshold shall require written concurrence from USFWS and CDFG within 30
days of receipt of request for written concurrence from the local jurisdiction and may
require additional minimizatiodmitigation measures.
Brown-headed cowbirds and other exotic species which prey upon the flycatcher shall
be removed from the site. For new developments adjacent to preserve areas that create
conditions attractive to brown-headed cowbirds, jurisdictions shall require monitoring
and control of cowbirds.
Biological buffers of at least 100 feet shall be maintained adjacent to occupied
Flycatcher habitat, measured from the outer edge of riparian vegetation. Within this
100-foot buffer, no new development shall be allowed, and the area shall be managed
for natural biological values as part of the preserve system. Buffers less than 100 feet
shall require written concurrence of the USFWS and CDFG within 30 days of receipt
of request for written concurrence from the local jurisdiction.
Suitable unoccupied habitat preserved within the FPA shall be managed to maintain or mimic
effects of natural fluvial processes (e.g., periodic substrate scouring and depositions).
b.
c.
d.
e.
f.
5.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 1 74
6. Ngtural riparian connections with upstream riparian habitat shall be maintained to ensure
linkage to suitable occupied and unoccupied habitat within the County MSCP and City of San
Diego MSCP Subarea Plans.
In addition, management will begin initially for all areas that once had documented southwest willow
flycatchers and any new populations will be managed per the MHCP standards.
Eflects to Critical Habitat
The entire wetland portion of the San Luis Rey River throughout the City of Oceanside is within the
FPA. However, only 831.6 acres of 895.8 acres of flycatacher proposed critical habitat are within the
FPA. This is mostly due to the County land within Guajome Park not being within the MHCP
planning area because the City of Oceanside does not have any authority over such land. However,
some adjacent upland habitat, which can provide foraging and dispersal habitat for the flycatcher and is
necessary for buffering the San Luis Rey River, are not in the FPA. As a result, some impacts to
flycatcher proposed critical habitat may occur from the MHCP Subregional Plan. However, the plan
requires 100-foot biological buffers to the San Luis Rey River and avoidance of wetland impacts as
described above.
The plan acknowledges the U.S. Army Corps of Engineers San Luis Rey flood control project that is
currently in formal consultation under section 7 of the Act with the Service. This project could have
significant impacts to flycatcher proposed critical habitat, however, the project is not a part of the
MHCP. However, if significant vegetation removal occurs as a result of the San Luis Rey River flood
control activities, formal consultation on this species and its critical habitat would need to be reinitiated
and reevaluated with a new biological baseline. This could affect the coverage of this species for all
Cities within the MHCP.
No flycatcher critical habitat has been designated within the City of Carlsbad, so no impacts will occur
from the City’s subarea plan.
Conclusion
We anticipate the proposed action will directly and indirectly effect the southwestern willow flycatcher
as described in the analyses above. The avoidance, minimization, and/or mitigation measures included
in the MHCP Subregional Plan and the City’s Subarea Plan will reduce any impacts that may occur to
this species. This Preserve will be adaptively managed, per the measures included in the MHCP
Subregional Plan and City’s Subarea Plan, which will further reduce the indirect effects and benefit the
species. After reviewing the current status of this species, the environmental baseline for the action
area, the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan and the City’s Subarea Plan is not likely to jeopardize the
continued existence of this species.
We anticipate the proposed action will adversely affect flycatcher proposed critical habitat. However,
critical habitat would remain functional and ensure conservation of the species for the following
reasons: 1) most of the critical habitat occurs within the FPA (93 percent); 2) the MHCP Subregional
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 175
Plan requires no-net-loss of wetland function and values; 3) the MHCP Subregional Plan requires
southwestkm willow flycatcher populations to receive narrow endemic species protection standards; 4)
the MHCP Subregional Plan requires occupied habitat within the FPA to be managed to restrict
activities that could degrade southwestem willow flycatcher habitat; 4) the MHCP Subregional Plan
requires all impacts to be mitigated fully; and 5) the MHCP Subregional Plan requires breeding season
restrictions, noise control, removal of exotic species, and biological buffers of at least 100 feet shall be
maintained adjacent to occupied southwestern willow flycatcher habitat, measured from the outer edge
of riparian vegetation. Thus, after reviewing the status, environmental baseline for the action area, and
the effects of the proposed action and the cumulative effects on southwestem willow flycatcher
proposed critical habitat, it is the Service’s biological opinion that the Subregional MHCP Plan is not
likely to adversely modify critical habitat proposed for the flycatcher. No southwestern willow
flycatcher critical habitat has been proposed within the City of Carlsbad, so no impacts will occur from
the City’s subarea plan.
Amount or Extent of Take
The Service anticipates that an unknown number of southwestern willow flycatcher could be taken in
the form of harm within a maximum of 0.4 acres of oak woodland (20 percent of 2 acres) and 16 acres
of riparian vegetation (20 percent of 80 acres) as a result of the City’s subarea plan. The incidental
take is expected to be in the form habitat loss because time-of-year restrictions will prevent direct
impacts to occupied nests. The amount of incidental take is expected to be low (not more than 1
individual) because of the wetland protection standards, treatment of the flycatcher as a narrow
endemic, and the lack of species presence in the City. This level of anticipated take is not likely
jeopardize the continued existence or recovery of the species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 176
Vireo bellii pusillus (Least Bell’s vireo)
Status of the SDecies
Listing Status
The least Bell’s vireo was federally listed as endangered on May 2, 1986 (51 FR 16474), and State
listed as endangered in California on October 2, 1980. A draft recovery plan was prepared for this
species in March 1998 (U.S. Fish and Wildlife Service 1998). Critical habitat was designated for the
least Bell’s vireo on February 2, 1994 (59 FR 34982), at 10 areas encompassing about 15,200 hectares
(38,000 ac.) in Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside, and San Diego
Counties.
Species Description
Vireo bellii pusillus is a small migratory songbird. It is olive-gray above and whitish on its underparts
with two dull white wing stripes and dull white to olive narrow margins on the outer border of its
wings and tail. Males and females are identical in plumage. V. b. pusillus is easily distinguished by its
song, a rapid bubbling series of rough notes, increasing in tempo and intensity toward a rapid climax.
Phrases of the song are alternatively slurred upward and downward. Eggs are on average 17.5
millimeters (0.7 in.) long, and dull white, often with fine brown, black, or reddish-brown dots
concentrated on the larger end (Brown 1993).
I V. b. pusillus is in the family Vireonidae, and is one of four subspecies of Vireo bellii (Bell’s vireo)
that have been recognized. Although all subspecies are similar in behavior and life history, they are
isolated from one another on both the breeding and wintering grounds (Hamilton 1962).
Distribution
The least Bell’s vireo formerly was found in valley bottom riparian habitats from Tehama County,
California, southward (but locally) to northwestern Baja California, Mexico. It ranged from near the
Pacific coast, in some areas, to as far east (inland) as the Owens Valley, Death Valley, and along the
Mojave River in California (Grinnell and Miller 1944). Except for a few outlying pairs, the subspecies
is currently restricted to southern California south of the Tehachapi Mountains and northwestern Baja
California (Garrett and Dunn 1981). Least Bell’s vireo breeding pairs currently occur in Monterey,
San Benito, Inyo, San Bernardino, Ventura, Los Angeles, Orange, hverside, and San Diego Counties,
California. The highest reported concentration is in San Diego County along the Santa Margarita
River (Small 1994). According to Grinnell and Miller (1944) 1,200 meters (4,000 ft.) is the upper
elevational limit to least Bell’s vireo Occurrence in coastal southern California.
Habitat Afinity
The least Bell’s vireo primarily occupies riparian habitats that typically feature dense cover within 1 to
2 meter (3 to 7 ft) of the ground and a dense, stratified canopy. It inhabits low, dense riparian growth
along water or along dry parts of intermittent streams. The understory is typically dominated by
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 177 -
sandbar willow (Salix hindsiana), mule fat (Baccharis salicifolia), young individuals of other willow
species s&h as arroyo willow (Salk lasiolepis) or black willow (Salix gooddingii), and one or more
herbaceous species (Salata 1983a, 1983b, Zembal 1984, Zembal et al. 1985). Important overstory
species include mature arroyo willows and black willows. Other overstory species that may contribute
to vireo habitat include cottonwoods (Populus spp.), western sycamore (Platanus racemosa), and coast
live oak (Quercus agrifolia). It primarily nests in small, remnant segments of vegetation typically
dominated by willows and mule fat but may also use a variety of shrubs, trees, and vines. Nests are
typically built within 1 meter (3 ft) of the ground in the fork of willows, wild rose (Rosa culifomica),
mule fat, or other understory vegetation (Franzreb 1989). Cover surrounding nests is usually a
moderately open midstory with an overstory of willow, cottonwood, sycamore, or oak. Crown cover is
usually more than 50 percent and contains occasional small openings. The most critical structural
component to least Bell’s vireo breeding habitat is a dense shrub layer at 0.6 to 3 meters (2 to 10 ft)
above the ground (Franzreb 1989). The birds forage in riparian and adjoining chaparral habitat (Salata
1983b).
Critical Habitat
In 1994, the Service designated areas encompassing approximately 38,000 acres in Santa Barbara,
Ventura, Los Angeles, San Bemardino, Rwerside, and San Diego Counties, California, as critical
habitat for the least Bell’s vireo (59 FR 4845). Approximately 49 percent of the vireo population in
the United States occurred within these 10 areas in 1994 (2,071 territories throughout the U.S. in
2000). The primary constituent elements of least Bell’s vireo critical habitat are defined as riparian
woodland vegetation that generally contains canopy and shrub layers, and includes some associated
upland habitats. The 10 vireo critical habitat areas are the Santa Ynez River in Santa Barbara County,
the Santa Clara River in Los Angeles and Ventura Counties, the Santa Ana River in Riverside and San
Bemardino Counties, and Coyote Creek, the upper Santa Margarita fiver (the lower Santa Margarita
hver was not designated and is on military land), San Luis Rey River, San Diego River, Sweetwater
River, Jamul-Dulzura Creeks, and Tijuana River in San Diego County. The three largest populations
of vireo within the 10 critical habitat areas are the Santa Ana River with 382 territories in 2000, the
San Luis Rey River with 233 territories in 2000, and the Tijuana River with 168 territories (the lower
Santa Margarita River was not designated critical habitat). These three areas combined represent 38
percent of the vireo territories within the United States.
All 10 areas are threatened by unauthorized clearing activities, placement of fill materials, and exotic
species. In addition, all but Coyote Creek in Anza Borrego Desert State Park and Sweetwater River,
which is already channelized, are threatened by flood control, water transfers, and channelization and
&version projects. More specifically, the Santa Ynez River is threatened by water diversions,
agncultural and urban development, and wetland draining. The Santa Clara River is most immediately
threatened by a 20,000 unit housing development and construction of two bridges throughout a
majority of this critical habitat area. The Santa Ana River continues to be threatened by two extensive
water conservation projects which have periodic impacts by flooding the habitat, the ongoing large
Santa Ana River Mainstem flood control project, Caltrans highway widening and bridge replacement
projects, large-scale human recreation (including an active airport on Corps-owned lands) and an
increasing human population and presence in or adjacent to the River. In San Diego County Coyote
Creek is threatened by cattle grazing, adjacent equestrian facilities, off-road vehicles, road projects,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 178 -
and state bills to re-establish a herd of feral horses in ha-Bomgo Desert State Park (SB1294) and
constructibn of a road running along Coyote Canyon within the boundaries of the Anza-Bomgo
Desert State Park (SB1338); the upper Santa Margarita River is threatened by development and
agriculture, the San Luis Rey and San Diego Rivers are threatened by agriculture, sand and gravel
mining, recreation, residentiaYcommerciaYindustrial development, transportation, wastewater
treatment, water supply projects, and flood control projects; the Sweetwater River is protected from
development but still faces indirect impacts from recreation; Jamul-Dulzura Creeks are threatened by
sand and gravel mining, water supply projects, and flood control projects and channelization; and the
Tijuana River is continually threatened by increasing disturbance and destruction of riparian habitat
from illegal off-road vehicle activity, vehicle activity by border patrol, and horseback riding.
Life History
The least Bell’s vireo exhibits year-round diurnal activity and is known to be a nocturnal migrant
(Brown 1993). This subspecies feeds primarily on insects and spiders, and rarely on fruit (Brown
1993). Insects consumed include true bugs, beetles, bees, wasps, ants, snails, grasshoppers, moths, and
butterflies (Terres 1980). The vireo forages primarily within willow (Salk spp.) stands or associated
riparian vegetation with forays into non-riparian vegetation including chaparral and oak woodlands
later in the breedmg season (Gray and Greaves 1984, Salata 1983b, Kus and Minor 1987). Individuals
travel between 3 and 61 meters (10 and 200 ft) while foraging, with the majority of these destinations
occurring within 30 meters (98 ft) of the edge of riparian vegetation (Kus and Minor 1987). Least
Bell’s vireo forage in all vertical vegetation layers from 0 to 20 meters (0 to 66 ft) but most feeding is
concentrated in the lower vegetation layers between 0 to 6 meters (0 to 20 ft) (Kus and Minor 1987,
Salata 1983b). Feeding behavior largely consists of collecting prey from leaves or in bark crevices
while perched or hovering, and less frequently by capturing prey by aerial pursuit (Salata 1983a,
1 98 3 b) .
Least Bell’s vireo are mainly monogamous, however, some individuals of both sexes are sequentially
polygamous within the breeding season (Greaves 1987). Male vireos contests and establishes breeding
territories (Barlow 1962) which range in size from 0.2 to 3.0 hectacres (0.5 to 7.4 ac.) (Gray and
Greaves 1984, Collins et al. 1992) with most averaging between 0.4 and 1.2 hectacres (1 and 3 ac.)
(U.S. Fish and Wildlife Service 1998). Territories in Bell’s vireo are maintained by threat and physical
confrontation early in the breeding season, and vocal warnings later in the season (Barlow 1962).
The breeding season for least Bell’s vireo extends from mid-March to mid- or late-September (U.S.
Fish and Wildlife Service 1986). A majority of the birds arrive from the Mexican wintering areas by
the end of March, and depart by end of August (Zeiner et al. 1990). Most breeding vireos depart the
breeding grounds by the third week of September, and only very few are found wintering in the United
States (Garrett and Dunn 1981, Salata 1983b). Nests are typically suspended in forked branches of
many different riparian species with no clear preference for any particular species (Nolan 1960, Barlow
1962, Gray and Greaves 1984). Least Bell’s vireo nests are usually placed between 0.9 and 1.5 meters
(3.0 and 4.9 ft.) from the ground with a range between 0.2 and 3.6 meters (0.7 and 11.8 ft.) (Dudek and
Associates 2000b). Females probably select the nesting sites but both genders participate in nest
construction (Barlow 1962). Nests appear to only be used once with new ones constructed after nest
failure or for successive broods (Greaves 1987). Between 2 to 5 (typically 3 or 4) eggs are laid shortly
after nest construction (U.S. Fish and Wildlife Service 1998). A typical clutch is incubated by both
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 179 -
parents for about 14 days with the young remaining in the nest for another 10-12 days (Pitelka and
Koestner i942, Nolan 1960, Barlow 1962). Least Bell’s vireo may produce two broods of young and
occasionally up to four per season, although it is thought that most are capable of successfully raising
only one brood (Franzreb 1989).
Bandng records have documented Bell’s vireo that have lived approximately seven years, however,
maximum life-span is probably longer (Brown 1993). Over two different time periods, within the
same population, Greaves and Gray (1991) found that only a small percentage of the vireos were older
than 3 and 4 years (8 percent and 15 percent). Survival rates measured as average nesting success has
been recorded for (US. Fish and Wildlife Service 1998). In a study of nesting success conducted in
several large drainages in southern California, the average percentage of nests to successfully produce
fledglings ranged from 46 percent (on the Santa Ana River) to a high of 74 percent (on the western
portion of the San Luis Rey River) (U.S. Fish and Wildlife Service 1998). Beyond one year,
survivorship increases averaging approximately 47 percent (U.S. Fish and Wildlife Service 1998).
Predation is common in least Bell’s vireo owing in part to the close proximity between nest and
ground (Franzreb 1989). Nest predation among least Bell’s vireo has been reported as high as 45
percent in the San Luis Rey river to as low as 8 percent on the San Diego hver (Salata 1983b).
Additional long-term research is needed over long periods of time to determine dispersal
characteristics of least Bell’s vireo (U.S. Fish and Wildlife Service 1998). Fledgling Bell’s vireo
expand their dispersal distances from about 10 meters (33 ft.) the first day to approximately 60 meters
(197 ft) several weeks after fledging (Hensley 1950, Nolan 1960). This distance has been shown to
increase to approximately 1.6 kilometer (1 mi.) during the same breeding season (Gray and Greaves
1984). Studies by Kus and Greaves have provided estimates of extra-watershed dispersal rates and
distances for least Bell’s vireo, with approximately 20 percent dispersing outside their natal drainages
over distances of up to 210 kilometer (130 mi.) (U.S. Fish and Wildlife Service 1998). Data collected
by Kus also suggests that males are more likely to disperse from their natal sites than females (U.S.
Fish and Wildlife Service 1998).
Population Trend
No other passerine (perching songbird) species in California is known to have declined as dramatically
as the least Bell’s vireo (Brown 1993). The narrow and limited nature of the habitat of the least Bell’s
vireo makes the subspecies more susceptible to major population reductions than the other subspecies
of Bell’s vireo. Intensive surveys between 1977 and 1985 of virtually all potential breeding habitat
were conducted (Gaines 1977, Goldwasser 1978, Goldwasser et al. 1980)’ resulting in occurrences at
only 46 of over 150 fomer localities. Once common, the vireo populations had decreased
substantially by the late 1980’s due to loss and degradation of habitat as well as from brown-headed
cowbird (Molothrus ater) parasitism (Goldwasser et al. 1980).
The regional population has increased from 300 pairs in 1986 to 1,500 pairs in 1996, primarily due to
the management of local cowbird populations (Kus 1998). Although the vireo has begun to recover
and approximately 2,000 least Bell’s vireos pairs were on territories in 1998, data indicate that the
United States breeding population in 1999 apparently declined. Population declines were noted at
Marine Corps Base, Camp Pendleton, the Prado Basin, and at other locales throughout the range of the
species in 1999 (U.S. Fish and Wildlife Service, unpublished data). The reason for this apparent,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 180 -
recent population decline is unknown. However, observed increases in the well-studied Prado Basin
population during the 2001 breeding season (Pike et al. 2001) and the detection of vireos at sites in
2002 where they had been absent for 25+ years (e.g., Santa Ana River Mouth) (U.S. Fish and Wildlife
Service, unpublished data) suggest that the vireo numbers may once again be on the rise.
Elsewhere in the subregion, major areas of suitable vireo habitat occur in Oceanside (at the San Luis
Rey River, Guajome Park, the Foss Lake/Pdgrim Creek area, and Loma Alta Creek).
Threats
Causes for decline of the least Bell’s vireo include destruction of habitat, river channelization, water
diversions, lowered water tables, gravel mining, agricultural development, and cowbird parasitism.
Vireos are known to be sensitive to many forms of disturbance including noise, night lighting, and
consistent human presence in an area. Excessive noise can cause vireos to abandon an area. Greaves
(1989) hypothesized that the lack. of breeding vireos in apparently suitable habitat was due to human
disturbances (e.g., bulldozers, off-road vehicles, and hiking trails). He further suggested that buffer
zones between natural areas and surrounding degraded and disturbed areas could be used to increase
the suitability of some vireo habitat. It appears that vireos nesting in areas containing a high proportion
of degraded habitat have lower productivity (e.g., hatching success) than those in areas of high quality
riparian woodland (Pike and Hays 1992). Additionally, widespread habitat losses have fragmented
most remaining populations into small, disjunct, widely dispersed subpopulations (Franzreb 1989). As
much as 90 percent of the original extent of riparian woodland in California has been eliminated, and
most of the remaining 10 percent is in a degraded condition (Smith 1977, Dah1 1990). Oberbauer
(1990) reported a 61 percent loss of riparian habitat for San Diego County. Habitat fragmentation
negatively affects abundance and distribution of neotropical migratory songbirds, in part by increasing
incidence of nest predation and parasitism (Small and Hunter 1988, Yahner and DeLong 1992).
Management programs aimed at reducing numbers of cowbirds have been considered very successful
at maintaining some local populations (Small 1994). Infectious disease is also a real threat due to the
potential for entire bird populations to be killed from diseases such as the West Nile Virus.
In October and November of 2003, southern California experienced significant wildfire activity. The
fires were distinguishable into 15 areas and burned a total of approximately 743,439 acres in Los
Angeles, Rtverside and San Bernardino, San Diego, and Ventura Counties.
It is unclear how much habitat occupied by least Bell’s vireo and southwestern willow flycatcher
burned in the recent fires because our location data is biased to areas with proposed projects (those
where surveys were necessary), could represent duplicative data, andor could be mapped as a large
polygon without the details of number of individual birds. However, 11 1,725 acres of riparian habitat
exist within Los Angeles, Riverside and San Bernardino, San Diego, and Ventura Counties and the
fires burned 5,668 acres (5 percent) of this riparian habitat. The most significant impacts occurred in
San Diego (3,186 acres), San Bernardino (1,304 acres), and Ventura (1,116 acres) Counties due to the
Cedar, Old, and Simi fires. For example, the Cedar fire burned 2,314 acres of riparian habitat in San
Diego County.
It is assumed that no individual vireos or flycatchers were harmed directly by these fires since the birds
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 181 -
are migratory and were not in the areas that bumed when the fires occurred. The 2004 nesting season
would su6stantially be adversely affected by the temporal loss of at least 1,104 acres of suitable habitat.
Four of the fifteen fires burned 1,104 acres of least Bell’s vireo critical habitat, which represents
approximately 3 percent of all critical habitat for the least Bell’s vireo. The Verdale and Simi fires
bumed approximately 427 acres of critical habitat unit 2. This represents 10 percent of critical habitat
within this unit. The Cedar fire burned approximately 63 acres of critical habitat unit 7, which
represents 7 percent of critical habitat within this unit. The OtayMne fire bumed approximately 614
acres of critical habitat unit 9, which represents 96 percent of critical habitat within this unit.
It is expected that these areas will recover and again provide suitable habitat for vireo or flycatcher,
albeit a longer process to become suitable flycatcher habitat. However, the degree to which this
disturbance will increase non-native invasive wetland species such as Arundo and tamarisk is
unknown, but should the fires result in more Arundo andor tamarisk in these areas, there could be a
net loss of suitable habitat until a restoration program is initiated and successful.
The largest most immediate threat to the vireo is flood control operation and maintenance activities in
the flood control portion of the channel. Such activities could significantly impact and degrade the
riparian vegetation to the point that flycatchers would not persist nesting in the area. Other ongoing
threats include large homeless encampments (which have been known to result in fires and the direct
destruction of vegetation), the presence of exotic vegetation including Arundo donax, natural
disturbance (e.g., fires or floods), groundwater pumping projects, and illegal fills. However, these
threats to the San Luis Rey River are not unique and are an existing problem to the survival and
recovery of the flycatcher throughout its range.
Recovery Plan
In March 1998, a draft recovery plan for the vireo was prepared by the Service. The Plan describes a
strategy for reclassification, recovery, and delisting. Instrumental to this strategy is securing and
managing riparian habitat within the historical breedmg range of the vireo, annual monitoring and
rangewide surveys, and research activities necessary to monitor and guide the survival and recovery of
the vireo population range wide. Criterion 1 of the Plan identifies the San Luis Rey River as one of 14
populatiodmetapopulation units that should be managed and protected to support stable or increasing
vireo populations/metapopulations, consisting of several hundred or more breeding pairs. A priority 1
recovery task includes protecting and managing riparian and adjacent upland habitats within the vireo’s
historical range and more specifically developing a management plan for the San Luis Rey River
which addresses the major threats of agriculture, flood control, water supply projects, sand and gravel
mining, recreation, residentialkommercialhndustrial development, transportation, wastewater
treatment projects, and unauthorized placement of fill materials, clearing, and herbicide activities (U.S.
Fish and Wildlife Service 1998).
Environmental Baseline
The MHCP planning area includes 2,665 acres of riparian habitat (Table 3-3 in MHCP Volume 1).
Vireos have been documented in Oceanside, Carlsbad, Encinitas, and Esconhdo. However, the only
major population occurs in the San Luis Rey RiverPilgrim Creek within the City of Oceanside. This
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 182
population is considered a major population and critical location within the MHCP. There are
approxim&ely 2,429 acres of vireo critical habitat in the MHCP planning area. More specifically, all
of the critical habitat is within the San Luis Rey River in the City of Oceanside.
-
’
The City includes 574 acres of riparian habitat. There is no critical habitat for the vireo designated
within the City’s planning area. Major areas of suitable vireo habitat in the City include the Sherman
property along Buena Vista Creek (5 territorial males; Helix 1999), the City’s Lake Calavera
mitigation bank, a State-owned area of riparian forest northeast of the upper end of Agua Hedionda
Lagoon, Macario Canyon extending southeast of the upper end of Agua Hedionda Lagoon, and the
riparian forest along Encinitas Creek, in Green Valley. Vireos have been recorded in all of these areas
except the Lake Calavera mitigation bank (U.S. Fish and Wildlife Service GIs data). In 1998, one
new population along Aqua Hedionda Creek west of El Camino Real was documented (Varanus
1997). Also, one pair of vireos were detected at the proposed intersection of College Boulevard and
Cannon Road, persisted at that location through the breeding season and nested successfully (Calavera
Hills Phase II Biological Opinion, FWS Consultation No. 1-6-01-F-1597). Construction of the road
intersection eliminated the habitat of this pair. An additional vireo was detected once, north of the
College Boulevard and Cannon Road intersection territory mentioned above. At least one territorial
male vireo was observed in June 2003 by several USFWS personnel in riparian vegetation along lower
Encinas Creek (Peter Beck, USFWS, pers. corn., 2003). In 2002, a vireo was documented within
approximately 200 m of the mouth of Encinas Creek (EDAW 2002). In addition, vireos have been
recorded on the La Costa Greens property, at the La Costa golf course, and north of Calle Barcelona
approximately 600 meters east of El Camino Real. Suitable riparian habitat can be found along
portions of some major and minor water courses within the Subarea and may support undocumented
populations of least Bell’s vireo. Additional areas of riparian vegetation not included in the City’s
preserve that may potentially support vireos include:
1. a strip of riparian woodland and southern riparian scrub approximately 400 feet northeast of
the intersection of College Boulevard and El Camino Real: this is a standards area in LFMZ
15;
the portion of Calavera Creek extending from the upper end of the northeastern “panhandle” of
Robertson Ranch, along the northwest side of the trailer park;
an area of southern willow scrub approximately 100 feet south of the intersection of Palomar
Airport Road and Armada Drive; and
a strip of open water and southern riparian scrub approximately 600 feet west of the Pacific
Ocean, extending southlsoutheast from Cannon Road.
2.
3.
4.
The MHCP planning area contains 2,429 acres of vireo critical habitat; all of which is located in and
around the San Luis Rey River. Thus, no critical habitat has been designated within the City of
Carlsbad. The San Luis Rey River critical habitat area (U.S. Fish and Wildlife Service 1994)
encompasses about 1,698 acres of riverine and floodplain habitats and adjacent coastal sage scrub,
chaparral, and other upland plant communities along approximately 22 miles of the River (73 1 acres of
the 2,429 are developed). This area extends from the Pacific Ocean to the town of Pala.
The critical habitat in the MHCP planning area is predominantly high quality vireo habitat occupied by
vireos. The population of vireos in the lower San Luis Rey River supports approximately 3 10 vireo
pairs, making the this the third largest vireo population in the United States and second largest
population within vireo critical habitat. This is mostly due to the lack of flood control activity within
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 183
the San Luis Rey flood control channel.
Considerable threats persist in the San Luis Rey River throughout the MHCP planning area. These
include the following (which are components of the baseline andor cumulative effects): 1) the
vegetation in the river is more susceptible to washing out during a flood because the control levees
constrict flood waters and increase the velocity and scouring force; 2) indirect effects such as pets,
garbage, invasive plants, and increased predation exist due to the construction of numerous housing
and commercial developments adjacent to the river; 3) fragmentation of the river has increased due to
the construction of bridges, State Route 76, and arterial roads; 4) large homeless encampments that
have been known to result in fires and direct destruction of vegetation (as described in annual
monitoring and cowbird trapping reports); 5) the presence of exotic vegetation, including Arundu
dunax, that can invade native riparian vegetation; 6) natural disturbances such as fires or floods, which
can temporarily destroy riparian vegetation; 7) groundwater pumping projects that can increase the
depth to groundwater thereby altering survival, growth, competition, and successional patterns in
riparian vegetation; and 8) illegal fills that destroy riparian vegetation. Though all the critical habitat
areas are facing significant threats and the three critical habitat areas with the largest populations of
vireos are actively threatened by flood control, recreation, and development pressures, all critical
habitat areas, which act as populatiodmetapopulation units, should be managed and protected to
support stable or increasing vireo populations/metapopulations (U.S. Fish and Wildlife Service 1998).
Effects of the Action
Direct Effects
No direct impacts to vireo nests, eggs, or young are expected from the MHCP Subregional Plan and
the Carlsbad subarea plan, since the MHCP requires the following condition for coverage: Projects
shall to the maximum extent practicable avoid impacts during the breeding season of the least Bell’s
vireo (generally March 15 - September 15). Projects that cannot be conducted without placing
equipment or personnel in or adjacent to sensitive habitats shall be timed to ensure that habitat is
removed prior to the initiation of the breeding season (generally before March 15).
Direct impacts to vireos are expected to be minimal since of the 2,665 acres of riparian habitat in the
MHCP planning area, 1,996 acres (75 percent) are within the FPA. In addition, the MHCP has
standards for avoidance, minimization, and mitigation of wetland impacts to assure no-net-loss of
wetlands within the planning area. However, impacts can occur to such wetland communities as
described in section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated
according to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP,
although there could be a temporal loss of such functions and values. The MHCP also,conserves 85
percent of known vireo locations and 93 percent of vireo locations in the BCLA. However, the flood
control operation and maintenance activities in the San Luis Rey River could adversely affect such
areas. If such impacts occur, the effects of the MHCP and City’s subarea plan would need to be
reanalyzed with a new species baseline. In addition, the MHCP has standards for avoidance,
minimization, and mitigation of wetland impacts to assure no-net-loss of wetlands within the planning
area. The MHCP also has species specific standards for vireos which consist of the following (MHCP
Volume 2):
1. As part of the project review process (e.g., CEQA) for individual projects within the MHCP
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 184
area, a qualified biologist possessing a Section lO(a)l(A) research least Bell’s Vireo permit for
t6s species must survey all areas containing potentially suitable habitat (riparian vegetation
communities) using approved survey protocols. Surveys shall occur prior to any proposed
impact regardless of location inside or outside of the FPA. Surveys shall be conducted when
impacts could occur as a result of inhrect impacts by placement of the project in or adjacent to
suitable habitat or through creation of suitable conditions for brown-headed cowbirds (e.g.,
agricultural fields, livestock presence, woodland parks, and roadsides).
Any take, both inside and outside of the FPA, shall be consistent with the conditions outlined
herein. Projects that impact least Bell’s vireo populations outside the FPA shall be required to
ensure sufficient management to maintain these populations.
Occupied habitat within the FPA shall be managed to restrict activities that could degrade least
Bell’s vireo habitat, including livestock grazing, human disturbance, clearing or alteration of
riparian vegetation, brown-headed cowbird parasitism, and insufficient water levels leading to
loss of riparian habitat and surface water. Area-specific management directives shall include
measures to provide appropriate successional habitat, cowbird control, and specific measures
to protect against detnmental edge effects, and will remove invasive exotic species (e.g.,
Arundo donax). Initiate cowbird trapping when cowbird parasitism rates exceed lopercent or
as recommended by monitoring results. Restrict human access to vireo-occupied habitat during
the breeding season (March 15 to September 15) except for qualified researchers or land
managers performing essential preserve management, monitoring, or research functions.
Projects having direct or indirect impacts to the least Bell’s vireo within the MHCP planning
area shall adhere to the following measures to avoid or reduce impacts:
a)
2.
3.
4.
The removal of native vegetation and habitat shall be avoided and minimized to the
maximum extent practicable. Determination of adequate avoidance and minimization
of impacts shall be consistent with Sections 3.6 and 3.7 of the MHCP plan. Deviations
from these guidelines shall require written concurrence of the USFWS and CDFG. For
temporary impacts, the work site shall be returned to preexisting contours and
revegetated with appropriate native species. All revegetation for temporary and
permanent impacts shall occur at the ratios specified in Section 4.3 of the MHCP plan,
with a minimum 3: 1 ratio for recreation of occupied or potential vireo habitat.
Revegetation specifications shall ensure creation and restoration of riparian woodland
vegetation to vireo quality. All revegetation plans shall be prepared and implemented
consistent with Appendix C (Revegetation Guidelines) and shall require written
concurrence of the USFWS and CDFG. If written objections are not provided by the
wildlife agencies within 30 days of receipt of written request for concurrence by the
local jurisdiction, then the deviation may proceed as approved by the local agency.
The wildlife agencies shall provide written comments specifylng wildlife agency
concerns.
Projects shall be carried out consistent with Appendix B (Standard Best Management
Practices).
Projects shall to the maximum extent practicable avoid impacts during the breeding
season of the least Bell’s vireo (generally March 15 - September 15). Projects that
cannot be conducted without placing equipment or personnel in or adjacent to sensitive
habitats shall be timed to ensure that habitat is removed prior to the initiation of the
breeding season (generally before March 15).
Construction noise levels at the riparian canopy edge shall be kept below 60 dBA Leq
b)
c)
d)
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 185 -
(Measured as Equivalent Sound Level) from 5 a.m. to 11 a.m. during the peak nesting
period of March 15 to July 15. For the balance of the dayheason, the noise levels shall
not exceed 60 decibels, averaged over a 1- hour period on an A-weighted decibel
(dBA) (i.e., 1 hour Les/dBA). Noise levels sha 11 be monitored and monitoring reports
shall be provided to the jurisdictional city, the USFWS, and the CDFG. Noise levels in
excess of this threshold shall require written
concurrence from the USFWS and CDFG and may require additional
minimizatiodmitigation measures.
Brown-headed cowbirds and exotic species detrimental to least Bell’s vireo shall be
removed from the site. For new developments adjacent to preserve areas that create
conditions attractive to brown-headed cowbirds, jurisdictions shall require monitoring
and control of cowbirds.
Biological buffers of at least 100 feet shall be maintained adjacent to occupied least
Bell’s vireo habitat, measured from the outer edge of riparian vegetation. Within this
100- foot buffer, no new development shall be allowed, and the area shall be managed
for natural biological values as part of the preserve system. Buffers less than 100 feet
shall require written concurrence of the USFWS and CDFG within 30 days of receipt
of written request for concurrence by the local jurisdiction.
Suitable unoccupied habitat preserved within the FPA shall be managed to maintain or mimic
effects of natural fluvial processes (e.g., periodic substrate scouring and deposition).
Natural riparian connections with upstream riparian habitat shall be maintained to ensure
linkage to suitable occupied and unoccupied habitat within the County MSCP and City of San
Diego MSCP Subarea Plans.
e)
f)
5.
6.
Of the 574 acres of riparian habitats supporting or potentially supporting least Bell’s vireo in the City,
approximately 498 acres (87 percent) are located within preserve areas, along with 95 percent of the
known point locations for this species. Therefore, approximately 76 acres (13 percent) of riparian
habitat may be impacted. Of an estimated 619 acres of vireo habitat located in biological core and
linkage areas, approximately 546 acres (88 percent) are expected to be conserved in preserve areas,
with potential impacts to 73 acres (12 percent). However, all impacts would be in the form of
temporal loss due to the no-net-loss of wetland policy.
Of the five major areas of suitable vireo habitat in Carlsbad listed above, all except the Sherman
property are included in the hardline preserve. The Sherman property is a Standards Area in the HMP.
Standards for development within Local Facilities Management Zone 25 (which includes the Sherman
property) include:
“Conservation of 75 percent of the Sherman property is required to provide adequate
connectivity within the regional gnatcatcher corridor. Align future Marron Road to minimize
impacts to sensitive biological resources and disruption of wildlife movement. Conserve
wetland habitats and set development back at least 100 feet .... Conserve and enhance riparian
vegetation along Buena Vista Creek with 200-foot buffers supporting natural vegetation
between wetland habitats and development. Prohibit fill or development within the existing
100 year flood plain except where required for Circulation Element roads, Drainage Master
Plan facilities, or other essential public infrastructure. Use sensitive design of any road or
utility crossing of Buena Vista Creek.”
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 186
A biologiFal constraints analysis for the Sherman property (Pacific Southwest Biological Services
2000) indicates that the site supports 50.02 acres (37.3 percent of the site) of southern arroyo willow
riparian forest. The zone-specific standards above would allow development of up to 33.5 acres (66.9
percent of the potential vireo habitat on site) of circulation element roads, drainage master plan
facilities, or other essential public infrastructure within potential vireo habitat. Though the City’s no-
net loss of wetlands policy ensures that riparian forest, riparian woodland, and riparian scrub habitats
will be replaced if impacted in the plan area, temporal loss of habitat, and degradation of habitat
quality are possible.
-
Indirect Effects
Indirect impacts are anticipated with the implementation of the MHCP Subregional Plan and the City’s
Subarea plan, and have the potential to cause significant adverse affects to the least Bell’s vireos within
the action area. These indirect impacts include habitat fragmentation, edge effects, noise effects,
disruption of the natural fire regime, changes in hydrology from adjacent development, increased
lighting, and the proliferation of exotic species, as generally explained and applicable in the “General
Indirect Effects’’ section.
Specifically, indirect impacts to the least Bell’s vireo could result from the degradation of riparian
habitats, adverse edge effects (including increased cowbird nest parasitism) and changes in the
hydrology or water quality.
The MHCP Subregional Plan provides measures to avoid and minimize such indirect effects as
described above. In addition, the City’s Subarea plan requires the following additional measures to
further minimize indirect impacts to vireos:
1. Manage preserve areas to minimize activities that would degrade riparian habitats, restrict the
alteration or clearing of riparian vegetation, control exotic invasive vegetation, control
cowbirds and predators, and maintain hydrology and water quality in riparian habitats. Restrict
activities in Vireo-occupied habitat during the breeding season, including no clearing of habitat
(April 15 to September 15). Where appropriate, restore or enhance riparian habitat suitable for
vireos and other sensitive riparian species.
Incidental take of the species or occupied habitat during the breeding season (March 15 to
September 15) is prohibited except as specifically authorized on a case-by-case basis. The
long-term preserve management plan shall provide area specific management directives for
known or potential Least Bell’s Vireo nesting areas, including specific adaptive management
measures to control brown-headed cowbirds, provide appropriate successional habitat, provide
upland buffers for known populations, minimize night lighting, minimize noise impacts, and
protect riparian areas against detrimental edge effects from adjacent development, recreational
impacts, and other direct and indirect impacts.
2.
In addition, management will begin initially for approximately half of the areas that have or once had
documented least Bell’s vireo and any new populations will be managed per the MHCP standards.
Effects to Critical Habitat
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 187 -
The entire wetland portion of the San Luis Rey River throughout the City of Oceanside is within the
FPA. Hiwever, only 1,120 acres our of 2,429 acres of vireo critical habitat are within the FPA. This
is partly due to the course mapping units used in the critical habitat designation process. However,
some adjacent upland habitat which can provide foraging and dispersal habitat for the vireo and is
necessary for buffering the San Luis Rey River are not in the ITA. As a result, some impacts to vireo
critical habitat may occur from the MHCP Subregional Plan. However, the plan requires 100-foot
biological buffers to the San Luis Rey River and avoidance of wetland impacts as described above.
The plan acknowledges the U.S. Army Corps of Engineers San Luis Rey flood control project that is
currently in formal consultation under section 7 of the Act with the Service. This project could have
significant impacts to vireo critical habitat, however, the project is not a part of the MHCP. However,
if significant vegetation removal occurs as a result of the San Luis Rey River flood control activities,
formal consultation on this species and its critical habitat would need to be reinitiated and reevaluated
with a new biological baseline. This could affect the coverage of this species for all Cities within the
MHCP.
No vireo critical habitat has been designated within the City of Carlsbad, so no impacts will occur
from the City’s subarea plan.
Conclusion
We anticipate the proposed action will directly and indirectly effect the least Bell’s vireo described in
the analyses above. The avoidance, minimization, and/or mitigation measures included in the MHCP
Subregional Plan and City’s Subarea Plan will reduce any impacts that may occur to this species. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan and
City’s Subarea Plan which will further reduce the indirect effects and benefit the species. We have
concluded that the City’s HMP will have no affect on vireo critical habitat, but the MHCP Subregional
Plan may adversely affect vireo critical habitat. However, the plan assures that impacts will be
minimized and mitigated appropriately. Thus, after reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the Subregional MHCP Plan and the City’s HMP is
not likely to jeopardize the continued existence or recovery of this species.
We anticipate the proposed action will adversely affect vireo critical habitat. However, critical habitat
would remain functional and ensure conservation of the species for the following reasons: 1) most of
the critical habitat occurs within the FPA (66 percent); 2) the MHCP Subregional Plan requires no-net-
loss of wetland function and values; 3) the MHCP Subregional Plan requires projects that impact least
Bell’s vireo populations outside the FPA to ensure sufficient management to maintain these
populations; 4) the MHCP Subregional Plan requires occupied habitat within the FPA to be managed
to restrict activities that could degrade least Bell’s vireo habitat; 4) the MHCP Subregional Plan
requires all impacts to be mitigated fully; 5) the MHCP Subregional Plan requires breeding season
restrictions, noise control, removal of exotic species, and biological buffers of at least 100 feet shall be
maintained adjacent to occupied least Bell’s vireo habitat, measured from the outer edge of riparian
vegetation. Thus, after reviewing the status, environmental baseline for the action area, and the effects
of the proposed action and the cumulative effects on vireo critical habitat, it is the Service’s biological
opinion that the Subregional MHCP Plan is not likely to adversely modify critical habitat designated
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 188 -
for the vireo. No least Bell’s vireo critical habitat has been designated within the City of Carlsbad, so
no impact‘s will occur from the City’s subarea plan.
Amount or Extent of Take
The Service anticipates that an unknown number of least Bell’s vireo could be taken in the form of
harm within a maximum of 76 acres of riparian vegetation as a result of the City’s subarea plan. The
incidental take is expected to be in the form of habitat loss because time-of-year restrictions will
prevent direct impacts to occupied nests. The amount of incidental take is expected to be low (not
more than 3 individuals) because of the wetland protection standards and the very limited number of
least Bell’s vireo known to occur within the City. This level of anticipated take is not likely jeopardize
the continued existence or recovery of the species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 189
PuZiuptiZa, caZifornica califonica (Coastal California gnatcatcher)
Status of the Smcies and Critical Habitat
Listing Status
The Service listed the coastal California gnatcatcher as threatened on March 30, 1993 (58 FR 16742).
In conjunction with the listing decision, the Service issued a special rule, pursuant to section 4(d) of the
Act, defining the conditions under which take of the gnatcatcher would not be a violation of section 9
(58 FR 65088-65096). This special rule recognized the State’s Natural Community Conservation
Planning (NCCP) Program, and several local governments’ ongoing multi-species conservation
planning efforts (e.g., the Multiple Species Conservation Plan [MSCP]) that intend to apply Act
standards to activities affecting the gnatcatcher. An interim process was established whereby
jurisdictions actively involved in NCCP planning would be allowed to develop up to five percent of
the remaining coastal sage habitat for projects that were consistent with the NCCP conservation
guidelines (California Departmen.t of Fish and Game and California Resources Agency 1993).
Critical Habitat
A final determination of critical habitat for the gnatcatcher was published in the Federal Register on
October 24, 2000 (U.S. Fish and Wildlife Service 2000). This determination was litigated in the U.S.
District Court, Central District of California. On June 11,2002, the U.S. District Court for the Central
District of California granted the Service’s request for a remand of the coastal California gnatcatcher
critical habitat designation so that we could reconsider the economic impact associated with
designating any particular area as critical habitat. The Court ordered us to publish a new proposed rule
by April 11,2003. In a subsequent order the Court held that the critical habitat designated for the
gnatcatcher should remain in place until such time as a new, final regulation becomes effective.
Critical habitat for this species was re-proposed on April 24,2003 (U.S. Fish and Wildlife Service
2003).
Currently designated critical habitat for the gnatcatcher includes 513,650 acres of Federal, state, local,
and private land in Los Angeles, Orange, Riverside, San Bemardino, and San Diego Counties, and has
been divided into 13 Critical Habitat Units (U.S. Fish and Wildlife Service 2000). Approximately
120,040 acres (or 25 percent) of the total 513,650 acres of gnatcatcher critical habitat, and 5 of the 13
Critical Habitat Units occur within San Diego County (U.S. Fish and Wildlife Service 2000). The re-
proposed critical habitat rule for the gnatcatcher includes 495,795 acres of Federal, state, local, and
private land, of which approximately 124,805 acres (25 percent) are located within San Diego County
(U.S. Fish and Wildlife Service 2003).
The primary constituent elements of gnatcatcher critical habitat, as described in both the final and re-
proposed critical habitat rules, are those habitat components that are essential for the primary
biological needs of foraging, nesting, rearing of young, intra-specific communication, roosting,
dispersal, genetic exchange, or sheltering (Atwood 1990). Primary constituent elements are provided
in (1) undeveloped areas, including agricultural lands, that support or have the potential to support,
through natural successional processes, various types of sage scrub, or (2) undeveloped areas that
support chaparral, grassland, or riparian habitats where they occur proximal to sage scrub and where
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 190
they may .be utilized by gnatcatchers for the biological needs of dispersal and foraging, and (3)
undeveloped areas, including agricultural areas, that provide or could provide connectivity or linkage
between or within larger gnatcatcher core areas, including open space and disturbed areas that may
receive only periodic use.
Distribution
The coastal California gnatcatcher occurs on coastal slopes in southern California, from southern
Ventura southward through Palos Verdes Peninsula in Los Angeles County through Orange,
Riverside, San Bernardino and San Diego Counties into Baja California to El Rosario, Mexico, at
about 30 degrees north latitude (Atwood 1991). In 1990, Atwood reported that ninety-nine percent of
all gnatcatcher locality records occurred at or below an elevation of 984 feet (ft). In 1992, Atwood and
Bolsinger reported that, of 324 sites of recent occurrence, 272 (84 percent) were located below 820 ft
in elevation, 315 (97 percent) were below 1,640 ft, and 324 (100 percent) were below 2,460 ft. Since
that time, additional data collected at higher elevations shows that this species may occur as high as
3,000 ft and that more than 99 percent of the known gnatcatcher locations occurred below 2,500 ft
(U.S. Fish and Wildlife Service 2000).
Habitat Afinity
Gnatcatchers typically occur in or near coastal sage scrub habitat. Coastal sage scrub is patchily
distributed throughout the range of the gnatcatcher, and the gnatcatcher is not uniformly distributed
witlun the structurally and floristically variable coastal sage scrub vegetation community. Rather, the
subspecies tends to occur most frequently within California sagebrush- (Artemisia califomica)
dominated stands on mesas, gently sloping areas, and along the lower slopes of the coast ranges
(Atwood 1990). An analysis of the percent gap in shrub canopy supports the hypothesis that
gnatcatchers prefer relatively open stands of coastal sage scrub (Weaver 1998). The gnatcatcher occurs
in high frequencies and densities in scrub with an open or broken canopy while it is absent from scrub
dominated by tall shrubs and occurs in low frequencies and densities in low scrub with a closed canopy
(Weaver 1998). Territory size increases as vegetation density decreases and with distance from the
coast, probably due to food resource availability.
Gnatcatchers also use chaparral, grassland, and riparian habitats where they occur adjacent to sage
scrub (Campbell et al. 1998). The use of these habitats appears to be most frequent during late
summer, autumn, and winter, with smaller numbers of birds using such areas during the breeding
season. These non-sage scrub habitats are used for dispersal, but data on dispersal use are largely
anecdotal (Campbell et al. 1998). Probable dispersing gnatcatchers have been documented in
vegetation dominated by such species as Brassica spp. (wild mustard), annual grasses, Salsola tragus
(Russian thistle), Bacchan's salicifolia (mule fat), Salk spp. (willow), and Tamarix spp. (salt cedar)
(Campbell et ai. 1998). Linkages of habitat along linear features such as highways and power-line
corridors may be of significant value in linlung populations of the gnatcatcher (Famolaro and Newman
1998). Although existing quantitative data may reveal relatively little about gnatcatcher use of these
other habitats, these areas may be critical during certain times of year for dispersal or as foraging areas
during drought conditions (Campbell et al. 1998). Breeding territories have also been documented in
non-sage scrub habitat. Campbell et al. (1998) discuss likely scenarios explaining why habitats other
than coastal sage scrub are used by gnatcatchers including food source availability, dispersal areas for
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 191
juveniles, temperature extremes, fire avoidance, and lowered predation rate for fledglings.
Life History
The California gnatcatcher is primarily insectivorous, nonmigratory, and exhibits strong site tenacity
(Atwood 1990). Diet deduced from fecal samples resulted in leaf- and plant-hoppers and spiders
predominating the samples. True bugs, wasps, bees, and ants were only minor components of the diet
(Burger et al. 1999). Gnatcatcher adults selected prey to feed their young that was larger than expected
given the dstribution of arthropods available in their environment. Both adults and young consumed
more sessile than active prey items (Burger et al. 1999).
The California gnatcatcher seems to become highly territorial by late February or early March each
year, as males become more vocal during this time period (Mock et al. 1990). In southwestern San
Diego County the mean breeding.season territory size ranged from 12 to 27 ac per pair and non-
breeding season territory size ranged from 12 to 42 ac per pair (Preston et al. 1998). During the non-
breeding season, gnatcatchers have been observed to wander in adjacent territories and unoccupied
habitat increasing their home range size to approximately 78 percent larger than their breeding territory
(Preston et al. 1998).
The breeding season of the gnatcatcher extends from mid-February through the end of August, with
the peak of nesting activity occurring from mid-March through mid-May. The gnatcatcher’s nest is a
small, cup-shaped basket usually found 1 to 3 ft above the ground in a small shrub or cactus. Clutch
sizes range between three and five eggs, with the average being four. Juvenile birds associate with
their parents for several weeks (sometimes months) after fledging (Atwood 1990). Nest building
begins in mid-March with the earliest recorded egg date of March 20 (Mock et al. 1990).
Post-breeding dispersal of fledglings occurs between late May and late November. Nest predation is
the most common cause of nest failure (Gnshaver et al. 1998). Gnatcatchers are persistent nest
builders and often attempt multiple broods, which is suggestive of a high reproductive potential. This
is, however, typically offset by high rates of nest predation and brood parasitism (Atwood 1990). Nest
site attendance by male gnatcatchers was determined to be equal to that of females for the first nest
attempt and then decline to almost a third of female nest attendance for later nesting attempts
(Sockman 1998).
Gnatcatchers typically live for two to three years, although ages of up to five years have been recorded
for some banded birds (Dudek and Associates 2000b). Observations indicate that gnatcatchers are
highly vulnerable to extreme cold, wet weather (Mock et al. 1990). Predation occurs in greater
proportion in the upper and lower third of the nest shrub. Predation is lower in nests with full clutch
sizes (Sockman 1997). Potential nest predators are numerous, and include snakes, raccoons, and
corvids (Grishaver et al. 1998). The California gnatcatcher also is known to be affected by nest
parasitism of the brown-headed cowbird (Muluthms ater). Nest parasitism apparently has resulted in
earlier nesting dates of the gnatcatcher which may help compensate for the negative effect of
parasitism (Patten and Campbell 1998). However, the gains in nest success from decreased nest
parasitism appear to be negated by increased nest abandonment due to predation before cowbirds have
migrated into an area (Braden et al. 1997).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 192 -
The natal,dispersal, for a nonmigratory bird, such as the gnatcatcher, is an important aspect of the
biology of the species (Galvin 1998). The mean dispersal distance of gnatcatchers banded in San
Diego County is reported at less than 1.9 miles (mi), however, birds were also documented moving up
to 6 mi from their natal territory (Bailey and Mock 1998). Although the mean dispersal distances that
have been documented above are relatively low, dispersal of juveniles is difficult to observe and to
document without extensive banding studies. Therefore, it is likely that the few current studies
underestimate the gnatcatcher’s typical dispersal capacity (Bailey and Mock 1998). Juveniie
gnatcatchers are apparently able to traverse highly man-modified landscapes for at least short distances
(Bailey and Mock 1998). Natural and restored coastal sage scrub habitat along highway corridors is
used for foraging and nesting by gnatcatchers and may serve important dispersal functions (Famolaro
and Newman 1998). Typically, however, the dispersal of juveniles requires a corridor of native
vegetation which provides foraging and cover opportunities to link larger patches of appropriate sage
scrub vegetation (Soul6 1991). These dispersal corridors may facilitate the exchange of genetic
material and provide a path for recolonization of areas from which the species has been extirpated
(Soul6 1991, Galvin 1998).
Population Trend
The gnatcatcher was considered locally common in the mid-l940’s, but by the 1960’s this subspecies
had declined substantially in the United States owing to widespread destruction of its habitat (Atwood
1990). By 1980, Atwood (1980) estimated that no more than 1,000 to 1,500 pairs remained in the
United States. In 1993, at the time the gnatcatcher was listed as threatened, the Service estimated that
approximately 2,562 pairs of gnatcatchers occurred in the United States. Of these, 30 pairs occurred in
Los Angeles County, 757 pairs occurred in Orange County, 261 pairs occurred in Riverside County,
and 1,514 pairs occurred in San Diego County (U.S. Fish and Wildlife Service 1993a). In October
1996, the total number of gnatcatchers in the United States was estimated at 2,899 pairs with two-
thirds occurring in San Diego County (U.S. Fish and Wildlife Service 1996), after subtracting out all
gnatcatcher pairs authorized for take under Habitat Loss Permits, approved Natural Community
Conservation Plans, Habitat Conservation Plans, and section 7 consultations. These population
estimates were intended to represent a coarse approximation of the number of gnatcatchers in southern
Cahfomia. Confidence intervals have not been calculated for these estimates and therefore, we can not
be sure of their precision.
Threats
The loss, fragmentation, and adverse modification of habitat are the principal reasons for the
gnatcatcher’s federally threatened status (U.S. Fish and Wildlife Service 1993a). The amount of
coastal sage scrub available to gnatcatchers has continued to decrease during the period after the listing
of the species. It is estimated that up to 90 percent of coastal sage scrub vegetation has been lost as a
result of development and land conversion (Westman 1981a,b; Barbour and Major 1977), and coastal
sage scrub is considered to be one of the most depleted habitat-types in the United States (arkpatrick
and Hutchinson 1977, O’Leary 1990). The elimination of nearby habitat may artificially increase
populations in adjacent preserved habitat; however, these population surpluses may be lost in
subsequent years due to crowdmg and lack of resources (Scott 1993). In addition, agricultural use,
such as grazing and field crops, urbanization, air pollution, and the introduction of non-native plants
have all had an adverse impact on extant sage scrub habitat. A consequence of urbanization that is
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 193 -
contributing to the loss, degradation, and fragmentation of coastal sage scrub is an increase in wildfires
due to anthropogenic ignitions. Wgh fire frequencies and the lag period associated with recovery of
the vegetation may significantly reduce the viability of affected subpopulations (Dudek and Associates
2000b). Furthermore, nest-parasitism by the brown-headed cowbird and nest predation threaten the
recovery of the gnatcatcher (Atwood 1980, Unitt 1984).
Early studies suggested that the California gnatcatcher is highly sensitive to the effects of habitat
fragmentation and development activity (Atwood 1990; ERCE 1990; Ogden unpublished data). The
loss of coastal sage scrub vegetation has been associated with an increasing degree of habitat
fragmentation, which reduces habitat quality and promotes increased levels of nest predation and
brood parasitism, and ultimately, increased rates of local extinction (Wilcove 1985, Rolstad 1991,
Saunders et al. 1991, Soule et al. 1988, 1992). Although the published literature on this subject is
based on studies in forested landscapes, the ecological implications of these studies are applicable to
other landscape types such as coastal sage scrub.
An important corollary of habitat .fragmentation is reduction of opportunity for successful natal
dispersal. Dispersal of gnatcatchers is critical to demographic and genetic soundness of the
population, and to population persistence of gnatcatchers in the fragmented habitat characteristic of
coastal southern California. Landscape connectivity enhances population viability for many species,
and, until recently, most species lived in well-connected landscapes (Beier and Noss 1998). Well-
designed studies offer strong evidence that corridors provide sufficient connectivity to improve the
viability of populations in habitats connected by corridors (Beier and Noss 1998). For relatively
sedentary bird species such as gnatcatchers, connectivity of habitat patches is probably the most
important landscape feature for maintaining species diversity of native biota (Soule et al. 1988).
Comdors counteract the effects of fragmentation, and should eliminate or minimize the attrition of
species over time by facilitating dispersal and recolonization (Willis 1974, Diamond 1975, Brown and
Kodric-Brown 1977, Frankel and Soule 1981, Soule and Simberloff 1985, Noss and Harris 1986,
Forman and Godron 1986, Diamond et al. 1987, Noss 1987). Linkages that support resident
populations of animals are more likely to function effectively as long-distance dispersal conduits for
those species (Bennett 1990).
In addition to development and land conversion, the recent Occurrence of large-scale wildfires
throughout southern California likely temporally reduced the amount of gnatcatcher habitat available
throughout the species’ range. For example, in October 2003, severe wildfires throughout southern
California resulted in the temporal loss of approximately 24,786 acres (21 percent) of designated
gnatcatcher habitat in San Diego County, and approximately 39,418 acres (10 percent) of designated
gnatcatcher critical habitat in the northern extent of the species’ range, which includes Orange,
Riverside, Los Angeles, San Bernadino and Ventura Counties (Figure 4); this loss represents an overall
temporal perturbation of 64,204 acres (12 percent) of designated critical habitat across the species’
range. These fires likely impacted several known source populations of gnatcatchers in San Diego
County.
Atwood et al. (1998) and Bontrager et al. (1998) found that extensive wildfires result in adverse
impacts to gnatcatcher populations within unburned areas, as well as within the bum area, due to
increased mortality resulting from excessive competitive interactions between resident birds within
unbumed areas and birds displaced by the fires. Studies conducted after the 1993 Laguna Fire in
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 194 -
Orange County (Wirtz et al. 1995, Bontrager et al. 1998, Beyers and Wirtz 1995, Atwood et al. 1998)
suggest that post-fire gnatcatcher population recovery is likely dependant on the amount of suitable
vegetation remaining within the burned area, as well as the presence of gnatcatcher source populations
in close proximity to areas affected by the fire. Furthermore, Beyers and Wirtz (1995) found that
following a fire, regrowing coastal sage scrub will not be recolonized by gnatcatchers until total shrub
cover approaches 50 percent, which is expected to take a minimum of 4 to 5 years. Due to the scope
and intensity of the recent Southern California fires, the areas affected are expected to take several
years to fully recover; therefore, any remaining gnatcatcher source populations, and remaining
gnatcatcher habitat, are important to the survival and recovery of the species.
Rangewide Conservation Needs of the Gnatcatcher
Based on the threats analysis above, the gnatcatcher has the following needs to survive and recover:
1. Functional habitat needs to be maintained in large, interconnected blocks sufficient to support
viable, interconnected populations. In some cases such areas may need to be enhanced and/or
created.
2. Gnatcatcher habitat needs to be protected from changes in natural fire regimes as a result of fire
suppression or increased fire frequency due to anthropogenic ignitions. Gnatcatcher habitat
needs to be managed to adequately mitigate those effects, should they occur.
3. The quality of gnatcatcher habitat needs to be maintained at high levels via management of
exotic plant and animal species (e.g., the brown-headed cowbird and feral cats).
Environmental Baseline
MHCP Planning Area
Currently, there are 9,152 acres of suitable gnatcatcher habitat in the MHCP planning area.
Gnatcatcher habitat is found in all of the participating MHCP cities. The MHCP tentatively estimates
the gnatcatcher population within the MHCP study area at 400 to 600 pair. The MHCP database (May
1999 update) currently includes 539 point locality records in the MHCP cities. This represents a
significant increase over the previous number of records included in the Public Review Draft MHCP
(378 points), largely due to incorporating new records from the San Diego Bird Atlas project. The Bird
Atlas data are less spatially biased than other survey data (e.g., from CEQA reports), which tend to
disproportionately cover properties proposed for development. Therefore, the current MHCP database
represents a more complete and less biased overview of species distribution in the study area.
Inspection of the overall distribution of gnatcatcher database points throughout the study area, the
density of points in well surveyed areas, and the overall high level of survey coverage in the MHCP
cities suggests that roughly 400 occupied gnatcatcher locations represent a reasonable, minimum gross
estimate of gnatcatcher pairs in the MHCP plan area in an “average” year, and that about 600 or more
pairs could occupy the MHCP plan area in an optimal year.
There are major populations and critical locations of gnatcatchers in Carlsbad, Escondido, Oceanside,
and San Marcos. Major populations occur at the proposed Carlsbad municipal golf course/Macario
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 195
canyon, Holly Springs/Calavera area, the La CostdUrriversity Commons area, north Oceanside
adjacent ti Camp Pendleton, Bemardo Mountain, San Pasqual Valley, Kit Carson Park, and the Quail
fills area. Critical population locations include the Calavera Lake/Calavera Highlands area, the La
CostaKJniversity Commons area, and north Oceanside adjacent to Camp Pendleton. Critical linkage
areas include the regional stepping-stone corridor through Oceanside, east Carlsbad, and southwest San
Marcos (see figure on page 4-338 of MHCP Volume 2).
The limited number of majorhitical gnatcatcher populations within the MHCP planning area
(described above) are isolated from each other. Genetic exchange may still occur via the few
remaining critical linkage areas. Gnatcatcher population reductions and fragmentation of gnatcatcher
habitat within the planning area are a direct result of increased urbanization. Because the participants
in the MHCP are incorporated cities located withm, or in close proximity to, the coastal portion of San
Diego County, it is expected that increased development pressures within these areas will continue.
HMP Planning Area
The HMP planning area is estimated to contain 100 to 150 pairs of gnatcatchers. Survey information
used in the development of the HMP resulted in 214 broadly distributed point localities for
gnatcatchers in the plan area. However, point locations do not necessarily reflect the current numbers
or distribution of gnatcatchers in Carlsbad. Most point locations are the result of project-specific
surveys that are patchily distributed in space and time. Some areas possibly supporting gnatcatchers
have never been surveyed, which may give the impression that the area is not occupied. Other sites
may have been surveyed more than once, and the repeated detections of gnatcatchers on the site over
multiple years may create the impression of greater gnatcatcher density on the site than actually occurs.
Other point locations may represent gnatcatchers that occurred historically in habitat that no longer
exists or has been degraded to the extent that it supports fewer or no gnatcatchers, creating the
impression that the City is capable of supporting a number or distribution of gnatcatchers that it
actually cannot. Large areas of the City without records of gnatcatcher occurrence (e.g., the between
Buena Vista and Agua Hedionda lagoons, west of El Camino Real) likely represent areas from which
gnatcatcher habitat was eliminated by urban or agricultural development prior to initiation of
widespread surveys for the gnatcatcher.
Conclusions that can be drawn from the distribution of gnatcatcher point locations in Carlsbad are (1):
that suitable gnatcatcher habitat is or was broadly distributed over the City, and (2): that gnatcatchers
occur, or occurred, or have the potential to occur, within much of this habitat, and thus, much of the
City. Within Carlsbad, major populations of gnatcatchers are found in the La Costa area in the
southeast, the Carlsbad Municipal Golf Course/Macario Canyon area in central Carlsbad, and the
Holly Springs/Calavera area in the northeast. Multiple gnatcatcher locations are also associated with
scattered coastal sage scrub patches in the northern portion of Carlsbad near Buena Vista Creek,
central Carlsbad between Palomar Airport Road and Batiquitos Lagoon, and the Fieldstone
Northwest/Rancho Carillo area of east-central Carlsbad. The Calavera Butte /Lake CalaverdCarlsbad
Highlands area in northeastern Carlsbad, and the La Costa /University Commons area of southeast
Carlsbad and San Marcos, are considered critical populations in the MHCP.
The HMP area includes 3,315 acres of coastal sage scrub and 3,790 acres of other habitat types that
may be used by gnatcatchers for biological needs such as breeding, foraging, or dispersal, or drought
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 196 -
refugia (Atwood et al. 1998; Campbell et al. 1998), including 968 acres of chaparral, 392 acres of
southern maritime chaparral, 574 acres of riparian habitat, and 1,856 acres of grassland.
A relatively large proportion of the potential gnatcatcher habitat in the City is considered of high
quality. The MHCP planning process modeled suitable gnatcatcher habitat throughout the planning
area. Modeling results show that the Carlsbad Subarea contains the most high-value habitat in the
MHCP area in comparison to other subareas. Based on the Gnatcatcher Habitat Evaluation Model the
Carlsbad area contains a total of 1,392 acres of high value, 263 acres of medium value, and 572 acres
of low value habitat for the gnatcatcher. Although individual habitat patches may be of high quality,
gnatcatcher habitat in Carlsbad is generally highly fragmented, consisting of isolated or narrowly
connected patches, with a high edge-to-area ratio. The City is located in a highly urbanized area and is
approximately 65 percent developed. Because of existing patterns of development and continued
agricultural use, there is a high degree of habitat fragmentation. None-the-less, gnatcatchers may still
persist in these areas. A review of gnatcatcher survey results in small patches of coastal sage scrub in
Oceanside indicated that gnatcatcher occupancy is persistent in small patches in coastal areas (Spencer
1997). Some of the smallest patches, that had been isolated for an average of 19 years, and some for
over 50 years, still had populations of gnatcatchers in them. In addition, a recent unpublished report by
the Service (Winchell and Doherty 2002), found that patch size was not a good predictor of occupancy
by gnatcatchers.
The MHCP identifies a “stepping stone corridor” that extends north and south across the Cities of
Oceanside and Carlsbad. From a regional habitat perspective, undeveloped areas in the coastal cities
of Carlsbad and Oceanside may serve as an integral “stepping stone linkage” connecting populations of
gnatcatchers in Orange and Riverside counties with populations to the south and east of Carlsbad.
These stepping stones may play an important role in keeping the overall metapopulation of
gnatcatchers intact and viable by maintaining genetic and demographic connectivity between other
larger habitat areas.
Existing hardline, proposed hardline, and proposed standards areas in the HMP were formulated with
the objectives of preserving suitable habitat for proposed covered species, and providing linkages to
allow habitat connectivity for the species. These linkages may provide connectivity with other hardline
areas within the Subarea, or to other habitat outside of the Subarea and MHCP, as described above
(under Project Description, Core and Linkage FPAs).
There are two primary north south linkages through Carlsbad. Along the eastern edge of the City,
Core areas 7, 5, and 3 along with links C and D encompass the regional stepping-stone corridor. Core
area 7 and its associated hardline area is the only preservation area, within the City of Carlsbad, that
will provide direct connectivity outside of the MHCP. Much of the preserve in this area has already
been conserved as part of the FieldstoneNillages of La Costa HCP (City of Carlsbad 1995). The
second north-south corridor occurs closer to the coast, west of El Camino. Link F (hardline and
standards areas) connects conserved lands in Core area 8 (Batiquitos Lagoon) to lands north of
Palomar Airport Road in Core area 4, of which the majority of lands are proposed hardline areas.
What remains of Link F is predominately existing open space that was set aside as part of the Aviara
development. A few small areas are proposed standard areas and will be subject to the HMP.
One of the largest blocks of habitat in the HMP is Core Area 3, where critical blocks of coastal sage
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 197 -
scrub are densely occupied by a critical population of gnatcatchers and other sensitive species. This
area connicts to core areas in Carlsbad via linkage C and D. About two thirds of this area has already
been conserved and/or developed as part of the Calavera Heights project. This project was permitted
prior to the ID". However, this area has an extension of Cannon Road proposed through it which, if
built, may have significant adverse affects to wildlife movement. The permit includes a special
condition to address this issue (see effects of the action).
The interface between the Cities of Carlsbad and Oceanside occurs at Buena Vista Creek through the
Sherman property and the Kelly-Bartman property in the City of Carlsbad. This area is a critical link
in the regional wildlife corridor, being planned to allow for movement of gnatcatchers, and other
species, between core habitat areas on Camp Pendleton and in northern Carlsbad. This corridor
extends southward from the Kelly-Bartman and Sherman properties on the northern border of the City,
through the Calavera Hills development, the Calavera Preserve and environs, the Holly Springs,
Cantarini, Mandana, and Kat0 properties, the Tchang property, Carlsbad Raceway and Palomar Forum
project sites, Rancho Carrillo open space, and out of the plan area into the adjacent unincorporated area
of San Diego County, approximately 0.6 mi north of the relatively extensive open space associated
with Villages of La Costa.
The Kelly-Bartman property is one of only two locations where gnatcatchers have the potential to
travel from suitable habitat in Oceanside to undeveloped habitat in Carlsbad, and is thus extremely
important to gnatcatcher conservation within the subregion. The site was approved for development
prior to the HMP. The open space remaining on-site will only be approximately 50 feet wide.
Although the corridor will be severely restricted in this location, it is only for a short distance. The
baseline condition for the Sherman Property is also constrained, in that the City of Carlsbad's
circulation element includes the extension of Marron Road through the site. This road has not been
permitted, however, and therefore will be addressed as part of the HMP (see effects of the action). A
special term and condition associated with the development of such a road has been added to the
permit to help avoid adverse effects to this corridor.
As mentioned above, several larger projects proceeded with their own individual permits, ahead of the
HMP because the permitting was delayed due to the Coastal Commission's review. The procession of
these projects further contributes to the fragmentation in the City, however, the patches of habitat
across the City of Carlsbad remain within the known dispersal distance for the gnatcatcher. The text
and figures of the ID" were not updated to reflect those projects already permitted; however, the
acreage of impacted versus conserved, by habitat type, in Table 8 of the HMP, was updated for all
projects except the Carlsbad Oaks North project (due to timing of approval - too close to the
reproduction date of the HMP addendum 2).
Conservation Needs of the Gnatcatcher in the Action Area
MHCP
Based on the current status of the gnatcatcher and its habitat within the MHCP planning area, the
gnatcatcher has the following needs in the action area relative to its range-wide survival and recovery:
1. The regionally critical stepping-stone corridor that connects core populations of gnatcatchers
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 198 -
within the MHCP planning area to core populations of gnatcatchers north and south of the
planning area needs to be maintained and managed. Conservation of this critical stepping-
stone corridor will maintain the viability of the species within the planning area by providing a
pathway for genetic exchange between core populations.
2. Critical populations of gnatcatchers and large blocks of gnatcatcher habitat capable of
supporting large concentrations of gnatcatchers, both within and adjacent to the planning area,
need to be maintained and managed. In some cases such areas may need to be enhanced.
3, Gnatcatcher habitat needs to be protected from the deleterious edge effects that result from
urbanization (e.g., introduction of exotic plants and animals, changes in natural fire regimes)
and managed to adequately mitigate those effects, should they occur.
Based on the current status of the gnatcatcher and gnatcatcher habitat within the HMP planning area,
the gnatcatcher has the following needs in this portion of the action area relative to its range-wide
survival and recovery:
1. Critical linkage areas that connect gnatcatcher habitat within the HMP planning area to areas
outside of the planning area (e.g., Sherman Property), thereby providing a pathway for genetic
exchange, need to be maintained and managed.
2. Critical populations of gnatcatchers, and large blocks of gnatcatcher habitat capable of
supporting large concentrations of gnatcatchers within the planning area need to be maintained
and managed. In some cases such areas may need to be enhanced.
3. Gnatcatcher habitat within the planning area needs to be protected from the deleterious edge
effects that result from urbanization (e.g., introduction of exotic plants and animals, changes in
natural fire regimes) and managed to adequately mitigate those effects, should they occur.
Critical Habitat
The MHCP and HMP planning areas are located within Critical Habitat Unit 3. The October 2000
final rule to designate critical habitat for the gnatcatcher identified Critical Habitat Unit 3 as
containing core gnatcatcher populations and gnatcatcher habitat of high to moderate value (as
described in the San Diego Association of Governments’ “Gnatcatcher Habitat Evaluation Model”,
dated March 24, 1999). In addition, the April 2003, re-proposal to designate gnatcatcher critical
habitat has identified Critical Habitat Unit 3 as biological linkage habitat connecting a source
population of gnatcatchers within Critical Habitat Unit 6 (Marine Corps Base Camp Pendleton), to
smaller, more fragmented populations of gnatcatchers within Units 4 (Fallbrook Naval Weapons
Statioh) and 5 (northern San Diego County), and to source populations of gnatcatchers within Unit 1
(MSCP preserve areas) (U.S. Fish and Wildlife Service 2003).
Within the planning areas for the MHCP and the HMP, some lands designated as critical habitat for
the gnatcatcher are also included in the April 2003, re-proposal. In some cases, lands designated as
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 199 -
critical habitat are not included in the re-proposal and some lands not previously designated as critical
habitat ar6 being proposed for designation. The analysis considered herein under formal consultation
involves all lands within the action area included in the 2000 critical habitat designation. We are
conferencing on lands within the action area currently proposed as critical habitat over and above those
currently designated.
MHCP
Approximately 20,385 acres of gnatcatcher critical habitat are designated within the MHCP planning
area. Of this, 12,710 acres (62 percent) are within the FPA. Most of the differences in spatial
distribution between the FPA and the critical habitat are due to the coarse mapping scale used by the
critical habitat mapping process (UTM grid) as compared to the refined scale used by the F'PA
mapping process (Parcel lines). However, Veteran's memorial cemetery in the City of Oceanside and
various parcels within southern San Marcos are not within the FPA, but possess important habitat for
gnatcatcher breeding, foraging and dispersal, and as such are designated critical habitat.
Approximately 22,676 acres of gnatcatcher critical habitat are proposed within the MHCP. Of this,
14,240 acres (63 percent) are within the FPA. Again, most of the differences in spatial distribution
between the FPA and the critical habitat are due to the coarse mapping scale used by the critical habitat
mapping process (UTM grid) as compared to the refined scale used by the FPA mapping process
(Parcel lines). In addition, most of the areas proposed as critical habitat overlap those areas designated
as critical habitat in the October 2000 designation. The differences in the two proposals include the
deletion of approximately 368 acres (29 acres within the FPA) designated as critical habitat in 2000.
These lands were the subject of a section 7 consultation or were in development prior to the
publication of the 2003, re-proposal. We consulted with the Corps, pursuant to section 7 of the Act, on
impacts to the gnatcatcher and its designated critical habitat within the boundaries of the University
Commons project in the City of San Marcos (biological opinions 1-6-00-F-2285 and 1-6-00-F-2703),
and construction of this project is currently underway. In addition, a portion of the San Elijo Hills
project in the City of San Marcos was developed prior to the publication of the proposed rule, and as a
result, is no longer proposed as critical habitat.
Additions to the October 2000, designation include approximately 2,656 acres (1,558 acres within the
FPA) that are proposed as critical habitat for the gnatcatcher. These areas are: (1) Lux Canyon in the
City of Encinitas; (2) a portion of La Mirada Canyon in the City of Vista; and (3) three smaller
unnamed parcels of land located in the northern, central, and eastern portions of the City of Encintas.
All of these areas are located within existing hardline preserves (100 percent conservation), with the
exception of the three small parcels in the City of Encinitas which are identified as softline preserve
areas (67 percent conservation).
Approximately 7,072 acres of gnatcatcher critical habitat are designated within the HMP planning area.
Of this, 4,229 acres (60 percent) are within the FPA. Most of the differences in spatial distribution
between the FPA and the critical habitat are due to the coarse mapping scale used by the critical habitat
mapping process (UTM grid) as compared to the refined scale used by the FPA mapping process
(Parcel lines).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 200 -
Approximately 7,338 acres of gnatcatcher critical habitat are proposed within the HMP. Of this, 4,258
acres (58 percent) are within the FPA. Again, most of the differences in spatial distribution between
the FPA and the critical habitat are due to the coarse mapping scale used by the critical habitat
mapping process (UTM grid) as compared to the refined scale used by the FPA mapping process
(Parcel lines). In addition, most of the areas proposed as critical habitat overlap those areas designated
as critical habitat in the October 2000, designation.
However, approximately 312 acres (41 acres in the FPA) proposed as critical habitat for the
gnatcatcher were not included in the October 2000, designation. These areas include: (1) the entire
Carlsbad Oaks North project area; (2) the Dawson Los Monos Reserve; (3) two small portions of the
existing hardline preserve within the Calavera Heights project area (approved by the city in 1993); (4)
a small portion of the existing hardline preserve along Encino Creek (adjacent to Costco); and (5) a
small portion of the existing hardline preserve in south eastern La Costa. All of these areas, except for
the Carlsbad Oaks North project site, will be 100 percent conserved under the City’s HMP. The
Carlsbad Oaks North project is subject to a section 7 consultation with the Corps (biological opinion 1-
6-00-F-2874), and therefore, is not being permitted through the HMP. In addition, approximately 34
acres (2 acres within the FPA) designated as critical habitat in 2000 were not included in the April
2003 proposed critical habitat designation because they are associated with the Calavera Heights
development project, where construction has begun.
Effects of the Action on the Gnatcatcher
Direct Effects
The MHCP Subregional plan requires that the following conditions (see MHCP Volume 2) be met by
individual cities, to receive coverage, for the gnatcatcher:
1.
2.
3.
4.
5.
Conserve at least 5,580 acres (61 percent) of the extant coastal scrub (including coastal sage
scrub, maritime succulent scrub, coastal bluff scrub, and mixed coastal sage scrub/chapmal
vegetation communities) within the MHCP plan area.
Conserve at least 55 percent (2,780 acres) of the remaining high- value breeding habitat and 60
percent (963 acres) of the remaining moderate-value breeding habitat in the MHCP plan area,
as determined using the MHCP habitat suitability model.
Conserve at least 68 percent (5,185 acres) of the coastal scrub that lies within the BCLA, and
conserve at least 64 percent of the high- value breeding habitat (2,551 acres) and 78 percent of
the moderate-value breeding habitat (891 acres) that lies within the BCLA.
Conserve at least 62 percent of known gnatcatcher localities (333 of 539 points), including 69
percent of the locations within the BCLA (295 of 43 1 points).
Restore and enhance at least 338 acres of coastal sage scrub in critical locations to increase
breeding habitat and improve functionality of a “stepping-stone” linkage through the MHCP
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 201
6.
7.
8.
9.
10.
11.
12.
pl~ area.
Conserve 400 to 500 acres of core gnatcatcher breeding habitat in the unincorporated area
southeast of the MHCP plan area, but contiguous with and contributing to the stepping-stone
comdor across the plan area. The gross acreage conserved may be larger than this to include
400 to 500 acres of gnatcatcher breeding habitat. The core area must be capable of supporting
at least 16 to 23 pairs of breeding gnatcatchers during good years, as determined by appropriate
habitat evaluations and verified by future monitoring.
Implement an adaptive management program to comprehensively monitor and manage
gnatcatcher habitat and populations throughout the preserve system. Increased coordination of
monitoring and management may improve knowledge of species’ requirements and habitat
quality in the study area.
Take of occupied gnatcatcher habitat must be mitigated according to approved MHCP
(Volume I, Section 4.3) or subarea plan ratios using one or more of the following measures:
(a) conservation of occupied gnatcatcher habitat inside the BCLA or in the
unincorporated core area;
(b) conservation of linkage areas identified by the MHCP as critical to regional gnatcatcher
population connectivity (whether or not such areas are currently occupied by
gnatcatchers or vegetated with coastaI sage scrub); or
restoration of gnatcatcher habitat within critical breeding or linkage areas identified by
the MHCP.
(c)
Carlsbad-Abide by all specific conditions and standards listed in the Carlsbad HMP,
including core area contributions, restoration obligations, reserve configuration standards, and
mitigation obligations. Ensure continued functionality of the gnatcatcher stepping-stone
linkage across the city, and especially at its boundaries with adjoining cities.
Encinitas-Ensure at least 67 percent conservation of coastal sage scrub within the city’s
sphere of influence via conservation standards to apply when properhes are proposed for
annexation to the city. Standards must ensure that the conserved areas are contiguous and
contribute substantially to the gnatcatcher core area and preserve design.
Escondido-mtigate take of occupied gnatcatcher habitat by conservation of occupied
gnatcatcher habitat elsewhere within the city (e.g., in or adjacent to the San Pasqual Valley),
elsewhere within the MHCP plan area, or within the unincorporated core area.
Oceanside-Conserve at least 664 acres of existing coastal sage scrub in the city, and restore
or enhance at least 164 additional acres of coastal sage scrub. Within the city’s designated
Wildlife Corridor Planning Zone, conserve at least 480 acres of biological open space in a
configuration that accommodates continued movement by California gnatcatchers between
State Route 78 and the San Luis Rey River. Of this 480-acre total, conserve at least 210 acres
of existing gnatcatcher breeding habitat (coastal sage scrub), and increase the net amount of
viable breeding habitat within the zone by at least 145 acres through restoration of disturbed,
developed, or annual grassland habitats to coastal sage scrub in key locations (Note: Acreages
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 202 -
13.
14.
15.
conserved and restored within the Wildlife Corridor Planning Zone count towards the 664 total
cdastal sage scrub and 164 total restoration acreage requirements for the city.) Conserve 120
acres of contiguous biological open space on the western portion of the city-owned El Corazon
property, including at least 45 acres west of the San Diego Gas and Electric transmission
easement and 75 acres along Garrison Creek on the northern portion of the property, as
detailed in the Oceanside Subarea Plan.
San Marcos-Maintain an average minimum width of 1,OOO feet for the linkage across
southwest San Marcos (University Commons area) between the unincorporated core area and
east Carlsbad. Restore or enhance at least 30 acres of high quality coastal sage scrub (not
including restoration requirements for the San Marcos Landfill) in the southwestern portion of
the city to increase habitat contiguity for gnatcatcher breeding and dispersal. (Note: The
County of San Diego must restore an additional 79.3 acres on the San Marcos Landfill, but this
is not considered an obligation of the City of San Marcos or the MHCP.)
Solana Beach-No specific conditions.
Vista-Conserve at least 67 percent of coastal sage scrub within the BCLA.
Implementation of the MHCP will adversely affect the gnatcatcher through the loss of approximately
38 percent of known point locations and 39 percent of the extant coastal sage scrub. However,
approximately 9 percent of the coastal sage scrub that will be lost is within areas that were not
considered to be biologically viable in the long terrn. Some critical locations will be substantially
impacted on already constrained properties; however, most major populations and other critical
locations will be substantially conserved. The MHCP will adversely affect the conservation needs of
the gnatcatcher by reducing the size of core population areas within the study area and the stepping-
stone corridor will be further constrained by development. However, edge effects will be minimized
through the management and monitoring required by the MHCP.
The FPA will conserve a minimum of 5,580 acres (61 percent) of the extant coastal sage scrub, 62
percent of known point locations, and 59 to 60 percent of the estimated carrying capacity within the
MHCP planning area. This results in conservation of 55 percent of the remaining high value
gnatcatcher habitat (2,780 acres), 60 percent of moderate value habitat (963 acres), and 63 percent of
low value habitat (1,531 acres). Of those areas that are within the BCLA and therefore are considered
to contribute the most to preserve viability, approximately 64 percent of the high value habitat and 78
percent of the medium value habitat will be conserved. In addition, the MHCP includes an additional
338 acres of coastal sage scrub restoration and an addtional400 to 500 acres of conservation in the
gnatcatcher core area. Thus, the FPA will contribute to meeting the conservation needs of the
gnatcatcher through the conservation and management of substantial portions of the major and critical
population areas within the MHCP study area, and the additional conservation and management of
core breeding gnatcatcher habitat in the adjacent unincorporated area. In addition, some losses will be
partially offset by population increases expected as a result of restoration, enhancement, and
management.
Although there will be a net loss of coastal sage scrub within MHCP, what remains will be sufficient
to continue to support gnatcatchers, within the action area, and to maintain the stepping-stone corridor
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 203 -
through the area. In addition, because the lands will be actively managed, monitored, and restored, the
overall cokervation function for the gnatcatcher should improve.
The HMP, with the permit’s special conditions (see project description), is consistent with the
conditions of coverage outlined above for the MHCP. Of the 3,315 acres of coastal sage scrub (the
gnatcatcher’s primary habitat) and 3,790 acres of other gnatcatcher habitat types, the HMP would
allow impacts to 1176 acres (35 percent) of coastal sage scrub, 292 acres (30 percent) of chaparral, 50
acres (13 percent) of southern maritime chaparral, 80 acres (14 percent) of riparian habitat, and 1149
acres (62 percent) of grassland. Conversely, 2139 acres (65 percent) of coastal sage scrub, 676 acres
(70 percent) of chaparral, 342 acres (87 percent) of southern maritime chaparral, 494 acres (86 percent)
of riparian habitat, and 707 acres (38 percent) of grassland will be Conserved. These patches are all
within the known dispersal distance (for gnatcatchers) of each other and will continue to function as a
stepping stone corridor through the City of Carlsbad.
Two critical gnatcatcher populations are located in the planning area (Core Areas 3 and 7). In Core
Area 3, which is the primary stepping stonehreedmg area in the Carlsbad-Oceanside corridor,
approximately 70 percent of the gnatcatcher locations included in the MHCP database will be
conserved. Approximately two thirds of this area has already been permitted and developed (see
baseline discussion), therefore the effects of this action are minimal. The HMP will ensure that the
long-term management and monitoring of these areas is consistent with the goals and objectives of the
MHCP. The remaining third of Core Area 3 is subject to this permit and includes the hard lined areas
of Holly Springs and Cantarini. Approximately 60 percent of the coastal sage scrub on these projects
sites will be conserved and 26 acres of coastal sage scrub will be impacted. The proposed
configuration will increase the edge-to-ma ratio in the remaining habitat and further constrain the
existing corridor. Approximately 8 acres of grasslands will be restored to coastal sage scrub, and the
land will be managed and monitored in perpetuity as part of the HMP, ensuring the preserve in this
area will continue to act as a stepping stone corridor.
Core Area 7, which has one of the largest populations of gnatcatchers within the MHCP, is
predominately comprised of the FieldstoneNillages of La Costa HCP (see baseline discussion);
therefore, the effects of this action are minimal. The proposed hardline Shelley project is the only area
subject to the HMP in this area. Shelley is predominately non-native grasslands and has no
gnatcatchers on site. Therefore, there will be no direct effects to gnatcatchers in this area of the City
from issuance of this permit. The area will be managed and monitored consistent with the standards
set forth in the MHCP and the HMP.
In addition to the two critical populations described above, there is also a major population in central
Carlsbad (Core Area 4). About half of this area is already conserved in and around Agua Hedionda
Lagoon. The remaining area is almost entirely proposed hardline projects. Within Core Area 4,
approximately 43 percent of the known gnatcatcher locations will be conserved in preserve areas. This
area includes the proposed municipal golf course and environs, which had a population of
approximately 15 pairs estimated in 1998, as well as Hub and Veterans Parks, and Kelly Ranch. The
HMF will cover these projects. Approximately 1,000 acres will be conserved in Core Area 4, of which
about 300 acres is Coastal sage scrub. The remaining acreage is predominately wetlands. This area
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 204
will contribute to the westerly north south linkage, as well as provide breeding habitat for the
gnatcatcher. Outside of these major/critical gnatcatcher population areas, additional known
gnatcatcher pairs are expected to be conserved in smaller patches of coastal sage scrub.
With regards to linkages, and as described above in the environmental baseline, the Kelly-Bartman
property has already been approved by the City. However, the Kelly-Bartman property is one of two
locations where gnatcatchers have the potential to travel from suitable habitat in Oceanside to
undeveloped habitat in Carlsbad. Due to the standards of the plan on the Sherman property, it is
expected that gnatcatchers, and other species, can continue to persist in this area and move through to
Oceanside. However, if built, the proposed Marron Road extension may have significant adverse
affects to wildlife movement. A busy roadway can cause direct mortality, and negatively influence the
ability of wildlife to obtain food and shelter, find a mate, raise young and prevent young from
dispersing (see Foreman and Alexander 1998, for an overview). Additionally, construction and
operational noise and lighting may preclude animal use of habitats adjacent to the road. We have
proposed to include a special condition to Carlsbad’s permit that will require further analysis and
design considerations (i.e. sound berms, bridges, and fencing) if the road is proposed for construction.
Through that process, we will work with the City to ensure that the connectivity through the site is
maintained. In addition, the City has committed to increasing the width of the portion of the corridor
on the adjacent property (driving range) if there is a request for a different use on the property.
The Holly Springs development would constrict an important regional habitat linkage that is currently
approximately 1,OOO meters wide to approximately 190 meters. Although significantly smaller than
what exists today, the remaining corridor will not preclude gnatcatcher dispersal. In addition, due to
the habitat conserved and managed surrounding the Holly Springs property, the on-site preserve should
continue to host gnatcatchers and allow gnatcatchers and other animals to disperse through the
property.
Also of concern in this area, is the proposed extension of Cannon Road, which could have significant
adverse affects to wildlife and wildlife movement, if built without specific design features to minimize
impacts to wildlife movement. These impacts would be similar to those described above for Marron
Road. The HMP includes this road in its circulation element. As with Marron Road, we have
proposed a special condition to Carlsbad’s permit for Cannon Road, that will ensure that these design
features are included in the project if the road gets built.
Although not ideal, patches of habitat (both small and large) that are located within dispersal distance
of each other have been shown to function as dispersal corridors for gnatcatchers. For example, in
Orange County, a bird that was banded at Crystal Cove State Park was observed at Newport - Banning
Ranch. This bird had to traverse a highly developed urban area to reach the Ranch (Will Miller, pers.
corn). Preliminary data from a study in San Diego County has documented banded birds crossing
Interstate 8 between patches of habitat. Based on these observations, as well as the studies cited above
in the species account, we anticipate that the stepping stone corridor that is proposed through Carlsbad
and the MHCP will continue to allow for genetic exchange and dispersal of birds, and that the patches
of habitat throughout the City will continue to support breeding pairs of gnatcatchers
The exact number of gnatcatchers that will be adversely affected by the Subarea plan is unknown. The
gnatcatchers found in areas cleared for development would be harmed by elimination of a portion of
their habitat. If the loss of habitat occurs during the breeding season, direct impact is expected to occur
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 205
through the death of adult birds, interruption of courtshp, nest building, destruction of eggs, and
disturbanie or death of unfledged young. To address this issue, the HMP requires no clearing of
occupied habitat between March 1 and August 15. However, in order to have no impacts to nesting
birds, eggs, or chicks, no clearing of occupied and potentially occupied habitat should occur between
February 15 and August 31; therefore we have proposed to include this restriction as a special term and
condition on Carlsbad’s permit.
Direct impacts to gnatcatchers may also result from the allowance of activities in preserve areas, such
as construction and use of trail networks, roads, other recreational use areas, fire management
techniques, and landscaping of adjacent properties. The draft OSMP addresses potential uses in the
preserve and includes measures to minimize the effects from these uses which the City has committed
to implementing.
If habitat is removed during the non-breeding season, impacts to adult gnatcatchers are still expected
due to the elimination of necessary foraging and sheltering areas for gnatcatchers. The removal of
1,231 acres gnatcatcher habitat is substantial because it reduces the ability for individuals to find
alternate, suitable habitat to forage.
Territory size of an animal (e.g., a gnatcatcher) is the result of a dynamic equilibrium between the
animal’s need for spatially distributed resources (e.g., food, water, shelter, nest sites, mates), the energy
the animal expends in acquisition and defense of those resources (Brown 1964, Carpenter et al 1983,
Gill and Wolf 1975, Myers et al 1979). It follows logically that reductions in habitat area may injure
or kill individuals.
Variable gnatcatcher breeding and post-breeding season territories and home range areas reflect the
changing size needed to meet the particular breeding, feeding, and sheltering requirements of the
species at any given part of the year. For example, Bontrager (1991) notes an 82 percent increase in
home-range size during the aon-breeding season, Preston et al. (1998), found a 78 percent increase in
post-breeding home range size, and Braden et aE. (1994) found an 86 percent increase in home range
size during the non-breeding season (when food resources are less abundant). Therefore, reduction of
available habitat will harm individual gnatcatchers by reducing the available resources for individual
gnatcatcher survival. Gnatcatchers need large non-breeding season territories for adequate sheltering
opportunities to reduce predation and increase survival.
The HMP will contribute to meeting the conservation needs of the gnatcatcher through substantial
conservation of major/critical populations in Core Areas 3,4, and 7, as well as the conservation of
several known gnatcatcher pairs in smaller patches of coastal sage scrub. The HMP will protect, in
perpetuity, approximately 3,315 acres of coastal sage scrub, along with approximately 3,790 acres of
other gnatcatcher habitat. In addition, these lands will be actively managed and monitored to minimize
detrimental effects from the adjacent development. Approximately 188.57 acres of land will also be
acquired within the gnatcatcher core area, through implementation of the HMP, of which 29.4 acres
have already been acquired. These lands are critical to the conservation of the gnatcatcher within San
Diego County. The HMP also includes approximately 104 acres of habitat restoration and
enhancement that will improve linkages.
Although there will be a net loss of coastal sage scrub within the HMP, what remains will be
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 206 -
sufficient to continue to support gnatcatchers, within the action area, and to maintain the stepping-
stone coGdor through the area. In addition, because the lands will be actively managed, monitored,
and restored, the overall conservation function for the gnatcatcher should improve.
Indirect Egects
MHCP and HMP
Indirect impacts have the potential to cause significant adverse affects to the gnatcatchers within the
action area. These indirect impacts include night lighting, human disturbance, depredation by
domestic pets, and habitat degradation, as generally explained and applicable in the “General Indirect
Effects” section.
The elimination of gnatcatcher habitat may result in displaced gnatcatchers seeking suitable habitats
elsewhere, with the potential for these gnatcatchers to attempt to establish territories in areas that are
already occupied. Gnatcatchers displaced from impacted areas by habitat destruction, and gnatcatchers
already occupying areas to which displaced gnatcatchers may emigrate, may have depressed lifetime
reproductive success due to disruptive effects of overcrowding in response to habitat loss. Atwood et
al. (1998) observed elevated populations of gnatcatchers in intact habitat adjacent to recently burned
habitat. Their observations suggest that some gnatcatchers relocated to adjacent habitat upon
destruction of the habitat they occupied.
However, elevated gnatcatcher populations in habitat adjacent to impacted habitats persisted for only
one breeding season, after which populations in refugia declined. Hagan et al. (1996) hypothesized
that such influxes of immigrants resulting from adjacent habitat loss may increase territorial
interactions such that reproductive success is temporarily reduced. Because gnatcatchers have a
lifetime breeding expectancy of only one to two years (Atwood et d. 1998b, Bontrager unpubl. data),
such effects could have important ramifications for dynamics of the gnatcatcher population within this
relatively isolated habitat fragment. Survival and reproductive success of displaced gnatcatchers
would probably be affected by the density of gnatcatchers in the intact habitat.
Additional development in the MHCP is expected to facilitate human access to sensitive habitat
resulting in habitat degradation and accumulation of trash that may attract predators that may prey on
gnatcatchers. Development within the MHCP study area may also result in increased potential
changes in fire frequency (e.g., suppressiodfuel modification), and invasion of the area by exotic flora
and fauna. Lighting from residential use and street lights may adversely affect adjacent habitat areas
and lead to increased predation of native species.
Indirect impacts could adversely affect the conservation needs of the gnatcatcher through the increase
in edge effects resulting from increased human intrusion, habitat degradation, night lighting, and
predation by domestic pets. However, a majority of the gnatcatcher points within the HMP are within
areas that initially will be managed and monitored consistent with the MHCP (Volume 3) which
provides the framework for management and monitoring that must occur within each city and
throughout the MHCP planning area. Tn addition, ultimately all preserved lands that are part of the
MHCP and HMP will require management actions, monitoring, and some land use restrictions
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 207
consistent with the MHCP (Volume 3) to minimize adverse indirect effects from surrounding
development, recreational use, and fragmentation.
Adaptive management and monitoring is a key component of MHCP and the HMP to ensure that
indirect effects are addressed to maintain a viable Gnatcatcher population in the action area, and
ensure that the stepping-stone comdor continues to function. As described in the project description,
the OSMP includes specific measures to address the above mentioned effects. As an example, fencing
and signs will be constructed in key areas around the reserve to minimize human intrusion into
sensitive areas, and rangers will patrol the area. These areas will then be monitored. If it is determined
that additional, or different, management activities are needed, then the management plan will be
revised accordingly. Provided the OSMP is fully implemented, it should be sufficient to minimize
indirect impacts and provide, in part, for a viable Gnatcatcher population in the action area as well as
allow for dispersal via the stepping-stone corridor.
Surnmm of HMP Effects to the Gnatcatcher
The HMP and the permit provide a basis for the conservation of this species and its associated habitats
by requiring the following:
1. Within Standards Areas, 75 percent of gnatcatchers shall be conserved. The long-term
preserve management plan shall provide area-specific management directives for all conserved
gnatcatcher locations and any other potential habitat, including specific measures to address
control of domestic pets, to reduce other edge effects, to minimize disturbance during the
nesting season, and to reduce the potential for habitat degradation due to unplanned fire.
Adaptive management may include measures to maintain or improve overall habitat quality,
including vegetation structure.
2. No clearing of occupied habitat may occur between February 15 and August 3 1.
3. Management Recommendations: Manage preserve areas to minimize edge effects, control
cowbirds and predators, prevent livestock overgrazing, and restrict human disturbance.
Prepare and implement a fire management program for preserve areas as part of the detailed
management plan. Where opportunities arise, enhance and restore coastal sage scrub within
preserve areas, with priority given to creation of Gnatcatcher breeding opportunities within
constrained linkages.
In order to minimize impacts to coastal California gnatcatcher, California rufous-crowned
sparrow, and orange-throated whiptail (Cnernidophorus hyperythrus beldingi) to the maximum
extent practicable, the Permittee shall ensure that if the City of Carlsbad proceeds with plans to
construct Cannon Road Reach 4, the extension of Melrose Drive through the Shelley Property,
or Marron Road through the Sherman Property, the Permittee shall consult with the Service
and California Department of Fish and Game on the preparation of a draft Environmental
Impact Report to ensure that all potential alternatives to construction of these roads are fully
considered. Any alternatives that include the construction of these roads shall meet the
following standards unless otherwise agreed to by the Service and California Department of
Fish and Game due to new information from scientific studies:
4.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 208 -
A,wildlife movement study that gathers wildlife movement data for at least one full year shall
be conducted preceding the design of any road undercrossings.
Noise within the underpasses shall be less than 60 dBA during the time of day that animals use
it. Sound walls shall be considered along portions of the road that pass over underpasses in
order to reduce noise levels, as increased traffic volume may decrease the frequency at which a
species uses the underpasses.
Shield corridors from artificial lighting. Use skylight openings within the underpass to allow
for vegetative cover within the underpass.
Design underpasses or culverts to be at least 30 feet wide by 15 feet high with a maximum 2: 1
length to width ratio. A more important variable is the openness of the underpass, which takes
into consideration the height, width, and length of the underpass (H*W/L). The openness
value shall be greater than 0.6.
Avoid co-locating human trails with wildlife movement corridodcrossings. Underpasses
shall be situated along primary travel routes away from areas containing noise and light
pollution and serve only wildlife needs since human presence andor recreational activities can
deter wildlife activity.
In order to prevent “at-grade” crossing attempts by the target species, fencing shall be installed
to complement the underpasses. Fencing shall be used to funnel wildlife away from at-grade
road crossings and toward undercrossings. Fencing shall be at least 8 feet high (measured from
the ground up) and placed along portions of the road that bisect the natural open space to
prevent end runs. Coyotes and deer are infamous for end runs, which means they will continue
to shift their movements to go around the end of a fence instead of using an underpass.
Furthermore, the fencing shall also have mesh that is less than 10 cm x 15 cm and be seated at
least 15 cm into the ground to prevent the animals from exploiting any weaknesses, which
would allow them access to the road. Finally, the fencing shall be installed to “funnel” the
animals towards each underpass by using wing fencing on both sides of the culvert.
Screen undercrossing openings with natural vegetation. Native vegetation shall surround all
underpass entrances and replace any proposed rock fill slope protection.
To maximize the width of the culvert available for wildlife movement, the water drainage area
in the base of each culvert shall be as narrow as possible and placed to the side, rather than the
center. Concrete V-ditches shall be eliminated to allow for natural stream flows, which
provide the elements critical for the movement of sensitive reptile and amphibian species.
5. In order to minimize impacts to coastal California gnatcatcher, California rufous-crowned
sparrow, and orange-throated whiptail to the maximum extent practicable, the Permittee shall
ensure that any opportunities to maintain and/or widen a corridor of habitat between Carlsbad
and Oceanside are fully considered. This includes the Permittee upholding the City of
Carlsbads agreement that should the driving range adjacent to the KellyBartman property be
proposed for a different use, that the City will ensure an on-site corridor is established on the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 209
dnving range property.
In addition, management will begin initially for a majority of the areas with documented coastal
California gnatcatchers and any new populations will be managed per the MHCP standards.
However, some important linkage areas for gnatcatchers will not be managed initially, but rather once
additional funding, such as through a regional funding source, is available.
Although there will be a net loss of coastal sage scrub within MJXP and the HMP, what remains will
be sufficient to continue to support gnatcatchers, within the action area, and to maintain the stepping-
stone corridor through the area. In addition, because the lands will be actively managed, monitored,
and restored, the overall conservation function for the gnatcatcher should improve.
Effects of the Action on Gnatcatcher Critical Habitat
Numerically, approximately 62 percent (12,7 10 acres) of the designated gnatcatcher critical habitat and
63 percent (14,240 acres) of the proposed gnatcatcher critical habitat within the MHCP planning area
is located within the FPA, and 38 percent (7,675 acres) of designated gnatcatcher critical habitat and
37 percent (8,436 acres) of proposed gnatcatcher critical habitat is located outside of the FPA.
However, as stated above, most of the differences in spatial distribution between the FFA and the
critical habitat are due to the come mapping scale used by the critical habitat mapping process (UTM
grid) as compared to the refined scale used by the FPA mapping process (Parcel lines). After taking
this into account, it is anticipated that approximately 90 percent of the designated and proposed critical
habitat within the MHCP planning area is located within the FPA.
A majority of gnatcatcher critical habitat within the FPA will be conserved. It is difficult to determine
an exact number of acres of gnatcatcher critical habitat that will be conserved within the FPA.
However, it is reasonable to assume a majority of gnatcatcher critical habitat will be conserved (over
75 percent) because hardline preserves provide 95 to 100 percent conservation, most other FPA lands
provide for 67 percent conservation, and very few provide only 50 percent conservation. In addition,
the MHCP standards for coastal sage scrub and the gnatcatcher species, and each City’s draft subarea
plan standards as analyzed in the Final EIS for The MHCP - Alternative 2, ensure that impacts to the
FPA will be avoided, minimized, and mitigated. Such measures include siting development in the
least damaging area and ensuring corridors and connectivity to off-site preserves are maintained. In
addition, conserved critical habitat within the FPA will be subject to the following
avoidancdminimization measures which will maintain and/or improve the quality of the habitat and
ensure its long-term viability:
1. Preserved areas will be managed to minimize edge effects, control cowbirds and predators,
prevent livestock overgrazing, and restrict human disturbance.
2, Where opportunities arise, coastal sage scrub within preserved areas will be enhanced and
restored, with priority given to creation of gnatcatcher breeding opportunities within
constrained linkages.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 210
3. 400-500 acres of core gnatcatcher breeding habitat, all of which is both designated and
prbposed gnatcatcher critical habitat will be conserved in the unicorporated area southeast of
the MHCP plan area, but contiguous with and contributing to the stepping-stone corridor
across the plan area. Thls habitat will be managed and monitored using the same methods that
will be used in preserved areas within the MHCP plan area.
The portion of designated and proposed critical habitat outside of the FPA would not be conserved.
Therefore, it is assumed that no more than 10 percent of the designated and proposed critical habitat
within the MHCP would be lost. Although there is a net loss of critical habitat, the overall
conservation function of the critical habitat unit in the MHCP area will continue to be met. Most of
what will be lost is areas that do not have constituent elements, but were included within critical
habitat due to the size of the mapping units. The small areas that will be lost, that does have
constituent elements, will be offset through the preservation, management, and monitoring of equal or
higher value lands, within the same unit, thus maintaining the conservation function of the critical
habitat unit. In addition, because MHCP includes management, monitoring, and restoration of coastal
sage scrub, it is anticipated that the conservation function may improve within the unit over time.
Numerically, approximately 60 percent (4,229 acres) of the designated gnatcatcher critical habitat and
58 percent (4258 acres) of the proposed gnatcatcher critical habitat within the HMP planning area is
located within the FPA, and 40 percent (2,843 acres) of designated gnatcatcher critical habitat and 42
percent (3,080 acres) of proposed gnatcatcher critical habitat is located outside of the FPA. However,
as stated above, most of the differences in spatial distribution between the FPA and the critical habitat
are due to the coarse mapping scale used by the critical habitat mapping process (UTM grid) as
compared to the refined scale used by the FPA mapping process (Parcel lines). After taking this into
account, it is anticipated that approximately 90 percent of the designated and proposed critical habitat
within the HMP planning area is located within the FPA.
Approximately 69 percent of the FPA is existing hardline preserve, and approximately 22 percent of
the FPA is proposed hardline preserve. Critical habitat within these two areas will be 100 percent
conserved. Critical habitat within the remaining 9 percent of the FPA will be no less than 67 percent
conserved. In addition, conserved critical habitat within the FPA will be subject to the following
avoidancehinimization measures which will maintain andor improve the quality of the habitat and
ensure its long-term viablity:
1. Mapped gnatcatcher locations within conserved habitat will be conserved.
2. Preserved areas will be managed to minimize edge effects, control cowbirds and predators,
prevent livestock overgrazing, and restrict human disturbance.
3. A fire management program will be prepared and implemented for preserve areas as part of a
detailed management plan.
4. Where opportunities arise, coastal sage scrub within preserved areas will be enhanced and
restored, with priority given to creation of gnatcatcher breeding opportunities within
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 21 1
cqnstrained linkages.
The portion of designated and proposed critical habitat outside of the FPA would not be conserved.
Therefore, it is assumed that no more than 10 percent of the designated and proposed critical habitat
within the HMP would be lost. As stated above for the MHCP, although there is a net loss of critical
habitat, the overall conservation function of the critical habitat unit in the HMP area will continue to be
met. Most of what will be lost is areas that do not have constituent elements, but were included within
critical habitat due to the size of the mapping units. The small areas that will be lost, that do have
constituent elements, will be offset through the preservation, management, and monitoring of equal or
higher value lands, within the same unit, thus maintaining the conservation function of the critical
habitat unit. In addition, because the HMP includes management, monitoring, and restoration of
coastal sage scrub, it is anticipated that the conservation function may improve within the unit over
time.
Cumulative Effects
Gnatcatcher
We anticipate that a wide range of activities will be determined to affect the gnatcatcher within the
action area. Such activities include, but are not limited to, urban development, illegal off-road vehicle
use, hiking and equestrian use, illegal trash dumping, road improvements, and utility projects.
Unincorporated County and other jurisdictions which have habitat allowance remaining under the 4(d)
rule (i.e., Escondido and Encinitas) will continue to permit habitat loss in accordance with NCCP
guidelines and the 4(d) special rule. Habitat loss in these jurisdictions has the potential to further
depress gnatcatcher populations and degrade (but not preclude) connectivity between biological core
areas and must meet the criteria established by the NCCP Conservation Guidelines (California
Department of Fish and Game and California Resources Agency 1993) in the MHCP and HMP and
the MSCP preserve to the south and east.
Unauthorized grading and filling of habitat would continue to affect the long-term viability of the
gnatcatcher in a regional context. In recent years, there have been several incidents of illegal grading
of habitat within the City of San Marcos and adjacent lands within adjacent cities and unincorporated
areas of the County of San Diego. Illegal grading, as well as trespassing by vehicles, equestrians,
hikers, and pets is expected to continue to occur.
Proposed hardline and proposed standards areas in the HMP were formulated with the objectives of
preserving suitable habitat for proposed covered species, and providing linkages to allow habitat
connectivity for the species. Theses linkages may provide connectivity with other hardline areas
within the Subarea, or to other habitat outside of the Subarea and The MHCP, as described above
(under Project Description, Core and Linkage FPAs). Populations located north and south of Palomar
Airport Road have the potential to be connected through the preservation of lands associated with Link
F (hardline and standards areas) and Core area 4, of which the majority of lands are designated as
proposed hardline areas.
MHCP and the HMP include monitoring and management which will minimize, in part, the
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 212 -
cumulativ9 effects described above. As an example, the reserves will be patrolled by rangers which
will have the authority to write citations for illegal activities such as trespassing and illegal dumping. It
is anticipated that because the lands will be actively managed and monitored, impacts will be detected
and addressed more quickly and efficiently than currently occurs, thus improving the overall quality of
the habitat. Establishment of the preserve, along with management and monitoring should be
sufficient to maintain the gnatcatcher population within the action area and the stepping-stone corridor
that currently exists across the action area. r
Critical Habitat
We anticipate that a wide range of activities will be determined to affect gnatcatcher critical habitat
within the action area. Such activities include, but are not limited to, urban development, illegal off-
road vehicle use, hiking and equestrian use, illegal trash dumping, road improvements, and utility
projects. Unincorporated County and other jurisdictions without approved Subarea Plans will continue
to permit habitat loss in accordance with NCCP guidelines and the 4(d) special rule. Habitat loss in
these jurisdictions has the potential to further depress gnatcatcher populations and degrade (but not
preclude) connectivity between biological core areas and must meet the criteria established by the
NCCP Conservation Guidelines (California Department of Fish and Game and California Resources
Agency 1993) in the MHCP and HMP and the MSCP preserve to the south and east. Unauthorized
grading and filling of habitat would continue to affect the long-term viability of the gnatcatcher in a
regional context. In recent years, there have been several incidents of illegal grading of habitat within
the MHCP and HMP study areas and unincorporated areas of the County of San Diego. Illegal
grading, as well as trespassing by vehicles, equestrians, hikers, and pets is expected to continue to
occur. These activities have the potential to adversely affect the conservation needs of the gnatcatcher
through the loss of critical habitat, as well as the reduction of core population size, further constriction
of linkages, and increased deleterious edge effects. However, the extensive management and
monitoring associated with the MHCP and HMP will help reduce the potential for such illegal
activities in the preserve areas and address any such impacts that may still occur.
Implementation of the MHCP and the HMP has the potential to preserve portions of critical habitat
currently located outside the FPA through application of conditions and standards to private, non-
Federal projects requesting coverage for the gnatcatcher. Although there may be a net loss of critical
habitat, because MHCP and the HMP include management, monitoring, and restoration of coastal sage
scrub, it is anticipated that the conservation function of the critical habitat unit may improve over time.
Conclusion
After reviewing the current status of the gnatcatcher, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biologcal opinion that the
project, as proposed, is not likely to jeopardize the continued existence of the gnatcatcher, and is not
likely to destroy or adversely modify designated and proposed critical habitat for the gnatcatcher. We
reached our non-jeopardy conclusion for the following reasons:
1. The majority (61 percent) of relatively large blocks of habitat occupied by major populations of
the gnatcatcher within the HMP planning area will be preserved and managed to avoid,
minimize, and mitigate the deleterious edge effects that result from urbanization. Given that
similar configurations of habitat created about 50 years ago within the City of Oceanside
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 213 -
cqntinue to support gnatcatchers without the benefit of such a management program, it is likely
that the preserved populations will persist.
Critical linkage areas that connect preserved gnatcatcher habitat within the HMP planning area
to habitat areas outside of the planning area (e.g., withm the City of Oceanside) will be
preserved, in part, and managed under the HMP such that they are likely to be functional.
The management program that will be implemented under the HMP is expected to enhance the
function of preserved habitat (relative to the existing condition) by addressing the factors that
cause deleterious edge effects associated with urbanization.
2.
3.
We reached our non-adverse modification conclusion for the following reasons:
1.
2.
3.
4.
5.
About 90 percent of designated critical habitat is expected to be preserved within the HMP
planning area.
Mapped gnatcatcher locations within preserved critical habitat will be conserved.
Preserved critical habitat areas will be managed to minimize edge effects, control cowbirds and
predators, prevent livestock overgrazing, and restrict human disturbance.
A fire management program will be prepared and implemented for preserved critical habitat
areas.
Where possible, coastal sage scrub within preserved critical habitat will be enhanced and
restored, with priority given to creation of gnatcatcher breeding habitat within linkage areas.
On this basis, the conservation function (demographic support and dispersal) of critical habitat within
the HMP planning area is likely to be maintained or enhanced.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual coastal California gnatcatchers
within a maximum of 1,176 acres of coastal sage scrub could be taken as a result of implementing the
HMP. The incidental take is expected to be in the form of harm through the loss of occupied habitat.
Take of chicks, eggs, and nests will be minimized by avoiding impacts to habitat during the coastal
California gnatcatcher breeding season. For the reasons explained above under the conclusion^'
section, this level of anticipated take is not likely to jeopardize the continued existence of the species
nor adversely modify its critical habitat.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 214
Zcteria virens (Yellow-breasted chat)
Status of the Swcies
Listing Status
The yellow-breasted chat is not a federally listed species. However, this species is on the State of
California Department of Fish and Game’s list of Species of Special Concern.
Species Description
The yellow-breasted chat is a large (approximately 25 grams), robustly-built wood warbler (Eckerle
and Thompson 2001). It has a large blackish bill with a strongly curved culmen, and a moderately
long tail. From the forecrown to the end of the tail, the upper parts are olive green to grayish olive.
The chin, throat, and breast are yellow, the belly and undertail coverts are dirty white. The face is
grayish with black lores, a bold white supercilium and submoustachial stripe, and a white eye crescent
on the lower eyelid. Sexes are similar, but the female is slightly duller, with gray lores. During the
breeding season, females have a pink mouth lining, while that of the males is black. Legs and feet are
dark gray-
Distribution
The yellow-breasted chat’s breeding range extends across most of the eastern U. S., and patchily from
the eastern front of the Rocky Mountains to the Pacific coast, throughout much of the western U.S. and
into Mexico (Kaufman 1996). The winter range of this migratory species extends from central Mexico
south into Central and South America.
Grinnell and Miller (1944) reported that chats bred over the entire length and breadth of California
exclusive of higher mountains and coastal islands, and were more numerous toward the interior. In
migration, chats were similarly widespread, but less restricted to riparian habitat.
In San Diego County, riparian woodlands of the coastal lowlands, especially along portions of the San
Luis Rey, Santa Margarita, and San Diego Rivers, and along Las Pulgas and Jamul Creeks, contain
breeding chats (Unitt 1984). Reports of chats also exist from the foothills of regons of eastern San
Diego County, although these individuals may have been migrants (Unitt 1984). Many other areas of
dense riparian vegetation in San Diego County support chats.
Habitat Afinity
In Northern California, the yellow-breasted chat occurs in well-developed riparian habitats (Harris,
1991). Nesting habitat consists of very dense scrub; brushy thickets; and briery tangles (usually
willows, blackberry, and grapevines), which are generally adjacent to streams, ponds, or swamps
(Zeiner et al., 1990; Kaufman, 1996). Yellow-breasted chat habitat preferences are very similar to
those of the least Bell’s vireo, and they frequently occur sympatrically. This species prefers various
types of edge habitat, including grass-shrub, shrub-forest, and water-shrub. Occasionally, they will nest
in dry overgrown pastures and in upland thickets along the margins of wooded areas (Kaufman, 1996).
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 215
In the miTed native and exotic riparian woodland in the lower Colorado River Valley, 16 of 28 yellow-
breasted chat nests were placed in saltcedar (Tarnank ramosissim) (S. Lynn, Point Reyes Bird
Observatory, unpubl. data). Brown and Trosset (1989) report that chats nest in tamarisk and native
shrubs in proportion to the occurrence of the different types of vegetation. Territory size is up to 4
acres (Brown, 1985). Dennis (1958) noted that nesting chats never occupied habitat patches less than
3 acres. Habitat preference for shrubby thickets in nonforested areas may be related to inclusion of
berries and fruit in their diet (Kaufman, 1996).
Life History
Diets consist of small invertebrates throughout summer and fruits and berries when available (Eckerele
2001). Prey is either gleaned from the foliage or from the ground.
The yellow-breasted chat is a seasonal migrant between southern Canada and Northern Mexico.
Spring migrants begin to arrive in southern California in late April. The fall migration patterns are not
well understood, but it is believed that these chats do not leave until late August.
Nesting occurs low to the ground (0.5 - 1 meter) withn dense thickets (Eckerele 2001). The nest type
is an open cup and consists of grasses, weed stems, leaves, bark, pine needles, and sometimes roots
and hair (Eckerele). Construction is done entirely by the female. The clutch consists of 3-6 cream-
colored eggs with brown, chestnut, pale gray and purple speckling. The female incubates for
approximately 1 ldays. Both parents feed the nestlings. Young fledge at approximately 8 days.
Occasionally two broods occur per year.
Population Trend
Small (1994) reports that the species has declined throughout California. The loss of riparian forests
and nest parasitism by the introduced brown-headed cowbird have been implicated as the primary
contributors to this decline (Small 1994). Along the north coast, populations are thought to be
relatively stable, not having suffered from similar declines (Remsen, 1978). Habitat loss on wintering
grounds in South America may have also played a role in the observed decline of this species.
California BBS data from 1966-1998 shows a nonsignificant increasing trend of 1.1 percent per year
(P = 0.27), along with sub-interval trends of 4.7 percent (P = 0.18) from 1966-1979 and 4.4 percent
(P = 0.61) from 1980-1999. However, this data exhibits several deficiencies, includmg low abundance
(less than 1.0 birddroute), low sample size (less than 14 routes), imprecision (3 percent-year change
would not be detected over the long term), and possible inconsistency in trend over time (sub-intewal
trends were significantly different [Pc 0.051 from each other) (Sauer et al. 1999). BBS data should
therefore be interpreted with extreme caution (Ricketts et al. 2000).
Threats
Population declines are associated with the loss of suitable habitat and brown-headed cowbird nest
parasitism. As much as 90 percent of the original extent of riparian woodland in California has been
eliminated, and most of the remaining 10 percent is in a degraded condition (Smith 1977, Dah1 1990).
Oberbauer (1990) reported a 61 percent loss of riparian habitat for San Diego County. Habitat
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 216 -
fragmentqtion negatively affects abundance and distribution of neotropical migratory songbirds, in part
by increasing incidence of nest predation and parasitism (Small and Hunter 1988, Yahner and DeLong
1992). Potential nest predators in California include Western Scrub Jays (Aphelocoma califomica),
woodrats (Neotorna sp.), rats (Rattus sp.), racoons (Procyon lotor), and several species of snakes.
Environmental Baseline
Within the MHCP planning area, most riparian woodland habitat is expected to support this species.
Yellow-breasted chats have been documented in Oceanside at the San Luis Rey River and in central
Oceanside, in Encinitas at lower Escondido Creek, and in Escondido at Kit Carson Park. Major areas
of suitable yellow-breasted chat habitat occur in Oceanside at the San Luis Rey Rwer, Guajome Park,
the Foss LakePilgrim Creek area, and Loma Alta Creek. There are many records of chats from these
areas (except Guajome Park), and a few records from riparian vegetation associated with Encinitas
Creek in Encinitas. The San Luis Rey River and Pilgrim Creek are critical locations and also support
major populations of this species.
The City includes 574 acres of riparian habitat. Major areas of suitable chat habitat in the City include
the Sherman property along Buena Vista Creek (5 temtorial males; Helix 1999), the City’s Lake
Calavera mitigation bank, a State-owned area of riparian forest northeast of the upper end of Agua
Hedlonda Lagoon, Macario Canyon extendmg southeast of the upper end of Agua Hedionda Lagoon,
and the riparian forest along Encinitas Creek, in Green Valley.
Biological resource information used in formulating the MHCP indicates that yellow-breasted chats
have been recorded in the City of Carlsbad at Macario Canyon, the Tchang property, and at the east
end of Batiquitos Lagoon. Chats have also been encountered along Encinas Creek near Hidden Valley
Road (P. Beck, USFWS, pers. comm.), and along Encinitas Creek in Green Valley (John Martin,
USFWS, pers. obs.). Suitable habitat (supporting willow/mulefat riparian) can be found along portions
of some major and minor water courses within the Subarea and may contain undocumented
populations of Yellow-breasted chat.
Effects of the action
Direct Egects
The MHCP Subregional Plan requires the following conditions be met for a city to receive coverage
for this species:
1. Manage suitable unoccupied habitat preserved within the FPA to maintain or mimic effects of
natural fluvial processes (e.g., periodc substrate scouring and deposition to rejuvenate riparian
vegetation).
Maintain biological buffers of at least 100 feet adjacent to occupied habitat, measured from the
outer edge of riparian vegetation.
Reserve areas will be managed to avoid and minimize clearing and alteration of riparian
vegetation, invasion of exotic plants and trees into the native riparian system, human
disturbance, brown-headed cowbird parasitism, insufficient maintenance of water levels
leading to loss of riparian habitat, and predation of adults and nests by domestic animals.
2.
3.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 217 -
4. As mitigation for project impacts, enhance or restore yellow-breasted chat habitat consistent
with management of other sensitive riparian bird species. Enhancement may include providing
sufficient water flow to ensure sustained willow growth, restriction of human activities within
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 218 -
th~ habitat during the breeding season, removal of invasive plant species, and predatorkowbird
control.
Protect upland buffers around riparian habitat. Buffer areas should be a minimum
of 50 feet and up to 100 feet wide.
5.
Direct impacts to yellow-breasted chat are expected to be minimal since, of the 2,665 acres of riparian
habitat in the MHCP planning area, 1,996 acres (75 percent) are within the FPA. In addition, the
MHCP has standards for avoidance, minimization, and mitigation of wetland impacts to assure no-net-
loss of wetlands within the planning area. However, impacts can occur to such wetland communities
as described in section 3.6 of MHCP Volume 1. Since such impacts would need to be fully mitigated
according to section 4.4.2 of MHCP Volume 1, no-net-loss of function or value will occur in MHCP,
although there could be a temporal loss of such functions and values. The MHCP also conserves 90
percent of known yellow-breasted chat locations. However, the flood control operation and
maintenance activities in the San Luis Rey River could adversely affect such areas. If such impacts
occur, the effects of the MHCP and City’s subarea plan would need to be reanalyzed with a new
species baseline. In addition, the MHCP has standards for avoidance, minimization, and mitigation of
wetland impacts to assure no-net-loss of wetlands within the planning area. Because habitat
requirements and potential threats to this species are very similar to the those for the least Bell’s vireo,
measures incorporated into the MHCP Subregional Plan to protect least Bell’s vireo are expected to
benefit yellow-breasted chats as well.
Of the 574 acres of riparian habitats supporting or potentially supporting yellow-breasted chat in
Carlsbad, approximately 498 acres (87percent) are located within preserve, along with 95 percent of
the known point locations for this species. Therefore, approximately 76 acres (13 percent) of riparian
habitat may be impacted. Of an estimated 619 acres of chat habitat located in biological core and
linkage areas, approximately 546 acres (88 percent) are expected to be conserved in preserve areas,
with potential impacts to 73 acres (12 percent).
Of the five major areas of suitable vireo habitat in Carlsbad listed above, all except the Sherman
property are included in the preserve. The Sherman property is a Standards Area in the HMP.
Standards for development within Local Facilities Management Zone 25 (which includes the Sherman
property) include:
“Conservation of 75 percent of the Sherman property is required to provide adequate
connectivity within the regional gnatcatcher corridor. Align future Marron Road to minimize
impacts to sensitive biologcal resources and disruption of wildlife movement. Conserve
wetland habitats and set development back at least 100 feet .... Conserve and enhance riparian
vegetation along Buena Vista Creek with 200-foot buffers supporting natural vegetation
between wetland habitats and development. Prohibit fill or development within the existing
100 year flood plain except where required for Circulation Element roads, Drainage Master
Plan facilities, or other essential public infrastructure. Use sensitive design of any road or
utility crossing of Buena Vista Creek.”
A biological constraints analysis for the Sherman property (Pacific Southwest Biological Services
2000) indicates that the site supports 50.02 acres (37.3 percent of the site) of southern arroyo willow
riparian forest. The zone-specific standards above would allow development of up to 33.5 acres (66.9
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 219
percent of the potential vireo habitat on site) of circulation element roads, drainage master plan
facilities, or other essential public infrastructure within potential vireo habitat. Though the City’s no-
net loss of wetlands policy ensures that riparian forest, riparian woodland, and riparian scrub habitats
will be replaced if impacted in the plan area, temporal loss of habitat, and degradation of habitat
quality are possible.
Additional areas of riparian vegetation not included in Carlsbad’ s preserve that may potentially support
chats include:
1.
2.
3.
4.
a strip of riparian woodland and southern riparian scrub approximately 400 feet northeast of
the intersection of College Boulevard and El Camino Real;
The portion of Calavera Creek extending from the upper end of the northeastern “panhandle”
of Robertson Ranch, along the northwest side of the trailer park
an area of southern willow scrub approximately 100 feet south of the intersection of Palomar
Airport Road and Armada Drive; and
a strip of open water and southern riparian scrub approximately 600 feet west of the Pacific
Ocean, extending southkoutheast from Cannon Road.
Because habitat requirements and potential threats to this species are very similar to the those for the
least Bell’s vireo, measures incorporated into the City’s Subarea Plan to protect least Bell’s vireo are
expected to benefit yellow-breasted chats as well.
Zndirect Effects
Indirect impacts have the potential to cause significant adverse effects to the yellow-breasted chats
within the action area. These indirect impacts include habitat fragmentation, edge effects, noise
effects, disruption of the natural fire regime, changes in hydrology from adjacent development,
increased lighting, and the proliferation of exotic species, as generally explained and applicable in the
“General Indirect Effects” section.
Specifically, indirect impacts to the yellow-breasted chat could result from the degradation of riparian
habitats, adverse edge effects (including increased cowbird nest parasitism) and changes in the
hydrology or water quality.
The Subarea plan and MHCP provide a basis for the conservation of this species and its associated
habitats by requiring the following:
1. Incidental take of the species or occupied habitat during the breeding season is prohibited
except as specifically authorized on a case-by-case basis. The long-tern preserve management
plan shall provide area specific management directives for known or potential Yellow-breasted
Chat nesting areas, including specific adaptive management measures to control brown-headed
cowbirds, provide upland buffers for known populations, and protect riparian areas against
detrimental edge effects from adjacent development, recreational impacts, and other direct and
indirect impacts.
Manage suitable unoccupied habitat preserved within the FPA to maintain or mimic effects of
natural fluvial processes (e.g., periodic substrate scouring and deposition to rejuvenate riparian
vegetation).
Maintain biological buffers of at least 100 feet adjacent to occupied habitat, measured from the
2.
3.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 220
ovter edge of riparian vegetation.
Reserve areas will be managed to avoid and minimize clearing and alteration of riparian
vegetation, invasion of exotic plants and trees into the native riparian system, human
disturbance, brown-headed cowbird parasitism, insufficient maintenance of water levels
leading to loss of riparian habitat, and predation of adults and nests by domestic animals.
As mitigation for project impacts, enhance or restore yellow-breasted chat habitat consistent
with management of other sensitive riparian bird species. Enhancement may include providing
sufficient water flow to ensure sustained willow growth, restriction of human activities within
the habitat during the breeding season, removal of invasive plant species, and predatorkowbird
control.
Protect upland buffers around riparian habitat. Buffer areas should be a minimum
of 50 feet and up to 100 feet wide.
4.
5.
6.
Once again, because habitat requirements and potential threats to this species are very similar to the
those for the least Bell’s vireo, measures incorporated into the plan to protect least Bell’s vireo are
expected to benefit yellow-breasted chats as well. In addition, management will begin initially for
approximately half of the areas with documented yellow-breasted chats and any new populations will
be managed per the MHCP standards. However, some important linkage areas for yellow-breated
chats and gnatcatchers will not be managed initially, but rather once additional funding, such as
through a regional funding source, is available.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will directly and indirectly effect
the yellow-breasted chat as described in the analyses above. The avoidance, minimization, and/or
mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any
impacts that may occur to this species. This Preserve will be adaptively managed, per the measures
included in the MHCP Subregional Plan and City’s Subarea Plan which will further reduce the indirect
effects and benefit the species. Thus, after reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the Subregional MHCP Plan and the City’s Subarea
Plan is not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an unknown number of yellow-breasted chats could be taken in the form
of harm within a maximum of 76 acres of riparian vegetation as a result of the City’s subarea plan.
The incidental take is expected to be in the form of habitat loss. The amount of incidental take is
expected to be low because of the wetland protection standards. This level of anticipated take is not
likely jeopardize the continued existence or recovery of the species..
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 22 1
Aimophilq mficeps canescens (Southern California rufous-crowned sparrow)
Status of the Species
Listing Status
The southern California rufous-crowned sparrow is a California Department of Fish and Game special
concern species with a CNDDB rank of G4T2T3S2S3. A. mficeps (full species) is also on the
Audubon Society’s state watch list for California. This species is not federally listed.
Species Description
Aimophila mficeps canescens is a small bird with a small bill. The wing and tail are longer and the
bill smaller than the similar A. r. mficeps. A. r. canescens are distinguished by the distinctly bicolored
bill with yellow-orange lower mandible. Upper parts are chestnut with grayish-buff streaking and the
underparts are brown with a grayish wash (Collins 1999).
Distribution
The rufous-crowned sparrow (species) is largely a resident species and occurs in central California,
northcentral Arizona, southwestern New Mexico, southeastern Colorado, northwestern and central
Oklahoma, south discontinuously to southern Baja California and mainland Mexico. East of the
Rocky Mountains, it winters from central and southern Oklahoma to northern Texas and south into
Mexico (Terres 1980). The current range and distribution of the southern California subspecies is
extremely restricted to a narrow belt of semiarid coastal sage scrub and sparse chaparral from Santa
Barbara south to the northwestern comer of Baja California, Mexico. (Grinnell and Miller 1944, Bent
1968, Zeiner et al. 1990, Unitt 1984).
Habitat Afinity
Optimal habitat for the southern California rufous-crowned sparrow consists of sparse, low brush or
grass, on hilly slopes preferably interspersed with boulders and rock outcrops (Grinnell and Mdler
1944, Bent 1968, Unitt 1984, Ehrlich et al. 1988, Root 1988). Some observers have noted a preference
for south-facing slopes and an affinity for California sagebrush (Artemisia califomica) over other
vegetative types (Gnnnell and Miller 1944, Bent 1968, Root 1988). It also colonizes grass that grows
as a successional stage following brush fires (Unitt 1984) and may occur on steep, grassy slopes
without shrubs if rock outcrops are present (Zeiner et al. 1990).
Life History
The rufous-crowned sparrow is diurnally active throughout the year (Zeiner et al. 1990). All
rufous-crowned sparrow activities are focused on and around the ground, usually in the area of dense
vegetative cover (Grinnell and Miller 1944, Bent 1968, Root 1988). The southern California rufous-
crowned sparrow forages on the ground in herbage and in leaf-litter beneath shrubs, gleaning from the
ground and foliage. It also gleans the foliage of live oak, foraging predominantly on insects during the
breeding season. During other times of the year its diet includes seeds, grasses, and forb shoots (Bent
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 222 -
1968). Rufouscrowned sparrows are relatively secretive, seeking cover in shrubs, rocks, and grass and
forb patchks, conceahng their nest on the ground at the base of a grass tussock or shrub or about 0.3 to
1 meter above the ground (Terns 1980). The nest is cuplike and made of twigs, bark strips, grasses,
and is lined with hair of deer, horses, and grasses (Terres 1980). This species breeds from mid-March
to mid-June with the peak of its breeding activity in May. Rufous-crowned sparrows are monogamous
and breeding territories may occur in groups (Pemberton 1910). Clutch size is generally 2-5 eggs.
Incubation is accomplished by the female only, but altricial young are tended by both parents (Harrison
1978). The rufous-crowned sparrow may occur in family groups postbreeding (Ehrlich et al. 1988).
Home range in southern California is approximately 1.5 hectacres (3.7 ac), with a coastal sage scrub
territory averaging 2.0 acres (Cody 1974, Bent 1968). The species is not gregarious and is generally
found in groups composed of no greater than five or six (Bent 1968) which exist in scattered
metapopulations across patchy landscapes. Eggs and nestlings are preyed upon by snakes and small
mammals (Bent 1968). Friedmann (1971) reported the first record of cowbird parasitism in this
species.
Population Trend
Fragmentation of suitable scrub habitat adversely affects the relative abundance of rufous-crowned
sparrows. They are more abundant in larger patches of suitable coastal scrub habitat than in smaller,
more fragmented patches (Bolger et al. 1997). From 1966 to 1991 there were significant increases in
Southern California (5.0 percent), Arizona (3.1 percent), and the entire western US. (3.6 percent).
However, between 1982 and 1991 populations declined in Texas (-8.1 percent) and the Osaga
Plain-Cross Timbers physiographic region (-5.8 percent). The overall trend for US. populations
between 1966 and 1995 was stable (Collins 1999). This data is for Airnophila mficeps. No data are
available specifically for the coastal subspecies, A. r. canescens.
Threats
The loss of coastal sage scrub for agriculture and urban development has reduced the available habitat
for this resident species (Bent 1968, Unitt 1984). Other stressors include a range of avian, mammalian
and reptilian predators, both native and domestic, that find the ground-nesting habit of this bird an easy
target (Bent 1968). Bolger et al. (1997) studied the 20-most common bird species within a 260 square-
kilometer area of coastal San Diego County in relation to edge and fragmentation sensitivity. The
rufous-crowned sparrow was found to be one of four species whose abundance is most reduced by
presence of edgedfragmentation.
Environmental Baseline
Within the MHCP planning area, southern California rufous-crowned sparrows are expected to occur
throughout the planning area in relatively large blocks of coastal sage srub. Southern California
rufous-crowned sparrows have been documented in Carlsbad, Encinitas, Escondido, Oceanside, and
San Marcos. Suitable habitat exists in all of the MHCP participating cities, however, no major
populations or critical locations for this species exists in the MHCP planning area.
Southern California rufous-crowned sparrows in the Subarea have been documented at La Costa
Rtdge, adjacent to Bressi Ranch and the Raceway property, east of Calavera Hills, west of La Costa
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 223 -
Greens, qd north and south of Palomar Airport Road (College Avenue). Population numbers are not
available at these locations. The presence of this species elsewhere in the Subarea is also unknown
due to a lack of survey effort. Nevertheless, documented observations indicate that this species occurs
within the Subarea. The majority of southern California rufous-crowned sparrows appear to be located
within the MSCP area near Lake Hodges, where larger unfragmented habitat is available.
Within the Subarea there are approximately 3,315 acres of coastal sage scrub and 1,856 acres of
grassland. Only a percentage of this habitat may be suitable for southern California rufous-crowned
sparrow based on their affinity to open scrub habitat and grassy slopes with scattered boulders. The
Subarea plan does not differentiate to this level, therefore the amount of available suitable habitat is
unknown.
Existing hardline, proposed hardline, and proposed standards areas are part of the Subarea Plan with
the intention of preserving suitable habitat for the southern California rufouscrowned sparrow among
other species. These areas are also intended to provide linkages and promote connectivity through
proposed and existing preservation areas throughout the Subarea.
Effects of the Action
Direct Efects
The MHCP Subregional Plan requires the following condition be met for a city to receive coverage for
this species: Manage reserve areas by controlling factors detrimental to southern California rufous-
crowned sparrow habitat, including livestock overgrazing, fire prevention and management methods,
presence of brown-headed cowbirds, and unnaturally abundant predators. As a mitigation option for
project impacts on southern California rufous-crowned sparrow habitat, restore coastal sage scrub
habitats in disturbed areas adjacent to occupied habitat.
Direct impacts to the southern California rufous-crowned sparrow are expected from the MHCP
Subregional Plan through habitat loss from development. However, the FPA will conserve a
minimum of 5,580 acres (61 percent) of the extant coastal sage scrub, 67 percent of known location
points within the MHCP planning area. Sixty eight percent of those areas that are within the BCLA
and therefore are considered to contribute the most to preserve viability. In addition, the MHCP
includes an additional 338 acres of coastal sage scrub restoration and an additional 400 to 500 acres of
conservation in the gnatcatcher core area which should also benefit southern California rufous-
crowned sparrow.
The Subarea plan proposes potential impacts to approximately 1,196 acres (36 percent) of coastal sage
scrub and 1,149 acres (62 percent) grassland habitats. The exact number of southern California rufous-
crowned sparrows that will be adversely affected by the Subarea plan is unknown. However, any
southern California rufous-crowned sparrows found in areas cleared for development would be harmed
by elimination of a portion of their habitat. If the loss of habitat occurs during the breeding season,
direct impact is expected to occur through the death of adult birds, interruption of courtship, nest
building, destruction of eggs, and dsturbance or death of unfledged young. If clearing or grubbing of
native vegetation is avoided between February 15 and August 31 there should be no impacts to nesting
birds, eggs, or chicks.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 224 -
Direct impacts to southern California rufous-crowned sparrow may also result from the allowance of
activities in preserve areas, such as construction and use of trail networks, roads, other recreational use
areas, fire management techniques, and landscaping of adjacent properties.
Indirect Effects
Indirect impacts have the potential to cause significant adverse affects to the southern California
mfous-crowned sparrow within the action area. These indirect impacts include night lighting, human
disturbance, depredation by domestic pets, and habitat degradation, as generally explained and
applicable in the “General Indn-ect Effects” section.
Specifically, research has suggested that development which has occurred in and adjacent to rufous-
crowned sparrow habitat and their associated territories may impact the abundance of this species.
Bolger et. al. (1997) documented that of the 20 scrub related species monitored, the rufous-crowned
sparrow had the most pronounced landscape (development) sensitivity. Incidence of the species was
low and showed a sharp decline between 100 and 500 meters of an edge, while it was abundant and
appeared to be a habitat generalist in larger patches in the landscape (Bolger et. al. 1997). The
abundance of this species in areas where fragmentation and edge effects are not as pronounced (Lake
Hodges) reflects this concept. Implementation of the MHCP Subregional Plan and City’s Subarea
Plan will result in adverse indirect impacts by the creation of fragmented habitat and increased edges.
Within the City of Carlsbad, core area 7 and it’s associated hardline area appears to the only
preservation area that will provide connectivity outside of the MHCP. The lands associated with Core
7 are currently or were historically under Section 7 consultation with the Service. Therefore, these
areas will not be associated with this baseline analysis. Existing populations located north and south of
Palomar Airport Road have a minimal amount of linkage corridor to provide for sufficient dispersal of
this species to the southeast (Core area 7). Conservation areas extending to the north of this population
area may provide a linkage to potential habitat at the Calavera Hills Preserve. However, the corridor(s)
are fragmented which may induce edge effects to the species.
The following conservation measures, as part of the Subarea plan, may help minimize these effects:
Manage preserve areas to minimize edge effects, control cowbirds and predators, prevent
livestock overgrazing, and restrict human disturbance. Prepare and implement a fire
management program for preserve areas as part of the detailed management plan. Where
opportunities arise, enhance and restore coastal sage scrub within preserve areas, with priority
gwen to creating of breeding opportunities within constrained linkages.
The long-term preserve management plan shall provide area specific management directives
for known or likely locations of Rufous-crowned Sparrow, including specific adaptive
management measures to protect against detrimental edge effects from adjacent development,
recreational impacts, and other direct and indirect impacts.
In addition, management will begin initially for a majority of the areas with documented California
rufous-crowned sparrows and any new populations will be managed per the MHCP standards.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 225
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will directly and indirectly affect
this species through habitat loss from development. However, 5,580 acres (61 percent) of the southern
California rufous-crowned sparrow habitat is within the FPA, 338 acres of coastal sage scrub habitat
will be restored, and 400 to 500 acres will be preserved in the gnatcatcher core area. The MHCP
Subregional Plan and City’s Subarea Plan will provide monitoring and management of this species that
will detect and minimize negative impacts that are affecting southern California rufous-crowned
sparrows. Additionally, this species will benefit from the connected preserve system that will be
managed and monitored in the City and throughout the MHCP in perpetuity. This Preserve will be
adaptively managed, per the measures included in the MHCP Subregional Plan, whch will further
reduce the indirect effects and benefit the species. After reviewing the current status of this species,
the environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s Subarea
Plan are not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual southern California rufous-crowned
sparrow within a maximum of 1,176 acres (35 percent) of coastal sage scrub and 292 acres of
chaparral could be taken in the form of harm as a result of the City’s subarea plan. The incidental take
is expected to be in the form of habitat loss. However, take of chicks, eggs, and nests will be
minimized by avoiding impacts to habitat within the Preserve during a majority of the southern
California rufous-crowned sparrow breeding season because it overlaps with the coastal California
gnatcatcher breeding season restriction. This level of anticipated take is not likely to jeopardize the
continued existence and recovery of the species.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 226
Passerculvs sandwichensis beldingi (Belding’s savannah sparrow)
Status of the Swcies
Listing Status
Belding’s savannah sparrow is not federally listed, but was listed as endangered under the State’s
Endangered Species Act by the California Department of Fish and Game on January 10, 1974.
Species Description
Passerculus sandwichensis beldingi is a small (1 1.0-15.5 cm in total length) emberizine sparrow.
They are sexually monomorphic in plumage with a streaky brown-to-gray nape, back and rump, a thin
brownish central crown stripe, and yellowish lores. The auricular area and submoustachial stripe are
also streaky brown. The throat, breast and belly are whitish to pale beige generally with brown streaks
and often a small central spot. The bill is horn colored, and the legs and feet are dull pinkish-gray.
Compared to other subspecies of savannah sparrow, P. s. beldingi is darker and more heavily marked,
with a longer, more slender bill msing and Beadle 1996).
Distribution
Belding’s savannah sparrows are distributed along the coast from Santa Barbara County, California,
south to northern Baja California, Mexico. Populations can be found at most estuaries and lagoons
throughout San Diego County. The Subarea has populations of Belding’s savannah sparrows at Buena
Vista Lagoon, Aqua Hedionda Lagoon, and Batiquitos Lagoon.
Habitat Afinity
Belding’s savannah sparrows are year-round residents, restricted to salt marshes, mud flat, and low
coastal strand vegetated habitats. They frequent areas dominated by Salicornia (pickleweed),
Allenrolfeu, Suaeda, Atriplex, and Distichlis and prefer to nest in the mid- to upper-littoral zones of
coastal salt marshes (Wheelwright and Rising 1993).
Life History
The Belding’s savannah sparrow is one of the 17 subspecies of P. sandwichensis (Wheelwright and
Rising 1993) all of which have the same basic pattern and habits (Wheelwright and Rising 1993).
Savannah sparrows are diurnally active throughout the year. Their diet is predominantly composed of
invertebrates during the breeding season. Small seeds tend to form a less significant part of their diet
during the breeding season than at other times of the year (Wheelwright and Rising 1993). They
scratch and glean on the ground, and pick food directly from low plants (Bent 1968). Cover is largely
provided by herbage in grasslands, wet meadows, Salicomia wetlands, and by associated scattered
shrubs and rocks. Savannah sparrows require dense ground cover in breeding season. In winter, they
seek similar cover in a variety of moist and dry grasslands, croplands, and in low vegetation along
beaches and shorelines. They nest in a hollow on ground and are usually concealed by overhanging
vegetation. They build cup nests of grasses, sedges and Salicomia, with an inner lining of fine grasses,
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 227
rootlets, apd hairs (Harrison 1978). Savannah sparrows have been observed bathing and drinking
(Nonis 1960, Bartholomew and Cade 1963), but can survive on a diet of seeds without drinking water
(Bartholomew 1972). In winter they occupy moist and dry grasslands, but prefer dense, short ground
cover. Savannah sparrows will also use low vegetation in croplands as well as beaches and shorelines.
Although Belding’s savannah sparrows are generally non-migratory, wintering populations of other
forms arrive on their wintering grounds from August to October, depending upon the subspecies, and
depart in April or May. Montane breeding populations of other savannah sparrow subspecies mostly
move downslope to winter. Savannah sparrows breed from April into July, with a peak in May and
June. They lay 2-6 eggs per clutch and often have two broods. Incubation lasts 10-13 days and the
altricial young fledge in 7-14 days. Incubation and brooding are accomplished mostly by the female
(Bent 1968, Harrison 1978, Ehrlich et al. 1988). Savannah sparrows are subject to predation by hawks,
snakes, and small mammals. They may be semicolonial, polygynous, roost in small groups on ground,
or form small flocks in winter, especially in saline emergent wetlands (Ehrlich et al. 1988).
Population Trend
A year-round resident in San Diego County, the Belding’s savannah sparrow population in the County
has increased from 651 pairs in 1977 to 1,105 pairs in 2001 (Zembal and Hoffman 2002). The
population in the County is expected to continue to increase due, in part, to the Batiquitos Lagoon
habitat enhancement project. However, statewide censuses of Belding’s savannah sparrows reveal
wide fluctuations in local population sizes, with local extinctions occurring in some years (Zembal et
al. 1988).
Threats
Belding’s Savannah sparrow populations historically declined due to destruction, fragmentation, and
alteration of their saltmarsh habitat. This species may also be impacted by human disturbance and
predation by introduced domestic and exotic predators (Zembal et al. 1987). Recent studies suggest
that exchange of individuals between saltmarshes is low and is reflected in genetic differences between
populations ([A. Powell pers. corn.] in Ogden Environmental 1998).
Environmental Baseline
Within the MHCP planning area, Belding’s savannah sparrow are expected to occur throughout the
planning area in salt marshes. Belding’s savannah sparrows have been documented in all four lagoons:
Agua Hedionda, Batiquitos Buena Vista and San Elijo lagoons. 280 acres of suitable habitat (southern
coastal salt marsh and mudflat vegetation) exists in the following MHCP participating cities: Carlsbad,
Encinitas, Oceanside, and Solana Beach. In 2001, Zembaland Hoffman recorded the following
number of nesting pairs in MHCP lagoons: 6 at Buena Vista, 22 at Agua Hedionda, 66 at Batiquitos,
and 75 at San Elijo lagoon. Salt marsh habitat within Agua Hedionda, Batiquitos, and San Elijo
lagoons are considered major populations and critical locations for this species in the MHCP planning
area.
The City includes approximately 15 1 acres of coastal salt marsh habitat in and along Buena Vista,
Agua Hedionda, and Batiquitos lagoons. In addition to coastal salt marsh in Carlsbad, the subregion
supports approximately 133 acres of suitable habitat, at the mouth of the San Luis Rey River (4 acres),
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 228
and the remainder at San Elijo Lagoon. Belding’s savannah sparrow populations have been
document6d in all salt marshes in the Subarea (Buena Vista Lagoon, Aqua Hedionda Lagoon, and
Batiquitos Lagoon). Recent surveys indicate that local populations are experiencing an overall
increase as within the Subarea. Between 1973 and 2001 surveys indicated a population increase from
37 territories to 94 territories (Zembel, et. al. 2001). Specifically, during 2001, surveys found 6
breeding pairs at Buena Vista Lagoon, 22 breeding pairs at Aqua Hedionda Lagoon, and 66 breeding
pairs at Batiquitos Lagoon (Zembel, et. al. 2001). The Subarea population represents approximately
three percent of the total California population and approximately nine percent of the San Diego
County population.
Effects of the Action
Direct Efects
The MHCP Subregional Plan requires the following conditions be met for a city to receive coverage
for this species:
1.
2.
3.
4.
5.
As part of the project review process (e.g., CEQA) for individual projects within the MHCP
area, a qualified biologist possessing a Section lO(a)l(A) research permit for this species must
survey all areas containing potentially suitable habitat (salt marsh, mudflats, and coastal
strands) using approved survey protocols. Surveys shall occur prior to any proposed impact
regardless of location inside or outside of the FPA. Surveys shall be conducted when impacts
could occur as a result of direct or indirect impacts by placement of the project in or adjacent to
occupied or potentially suitable habitats.
Implement wetland mitigation standards that require a minimum 4: 1 replacement ratio for
unavoidable impacts to occupied habitat for this species, with particular emphasis on restoring
upper marsh zones preferred by this species. Control recreational use by humans within
pickleweed habitats to reduce trampling.
Manage occupied areas to control activities that degrade Belding’s Savannah sparrow habitat,
including human disturbance, filling and diking of salt marsh habitat, predation of adults and
nests by introduced feral and domestic animals (e.g., dogs and cats), adverse changes in water
level, water quantity and quality, and introduction of pesticides and other contaminants into
preserve wetlands.
As mitigation for project impacts, enhance, restore, or create salt marsh habitat within the
preserve to allow for the expansion of Belding’s Savannah sparrow populations into new
locations.
Protect upland buffer areas to minimize edge effects. Buffer areas should be a minimum of 50
feet and up to 100 feet wide where possible.
The MHCP Subregional Plan will have little to no direct impacts to Belding’s savannah sparrow
because all of the lagoons where the species occurs and where the major populations and critical
locations are located, will be 100 percent conserved. Only 74 percent of the location points throughout
the MHCP planning area are within the preserve areas. However, this species is provided even greater
protection through the conditions for estuarine species in Appendix E of MHCP Volume 2 and the no-
net-loss of wetland policy.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 229
and coast@ salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve. There are no projects proposed for this area,
however, impacts may occur in the future in the right-of-ways due to projects such as road widening
which would be beyond the control of the City. Such impacts would be analyzed and permitted under
a different mechanism than the MHCP. 339 acres of southern coastal salt marsh and freshwater marsh
vegetation communities constitute potential habitat for white-faced ibis. A small amount of additional
habitat in the lagoons are also technically not in the mapped area of the preserve, however, no projects
are planned for this area by the City and 100 percent conservation due to MHCP standards for
avoidance, minimization, and mitigation of wetland impacts assure no-net-loss of lagoon wetland
habitat. However, impacts can occur to such wetland communities as described in section 3.6 of
MHCP Volume 1. Since such impacts would need to be fully mitigated according to section 4.4.2 of
MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there could be a
temporal loss of such functions and values. The MHCP conditions for estuarine species and fact that
all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due to these
standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine, salt
marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, direct take of animal
species is expected to be minimized because any areas proposed for hsturbance would be avoided
where MHCP species or nests are known or found to be present.
Indirect Eflects
Indirect impacts have the potential to cause significant adverse effects to Belding’s savannah sparrows.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets, and
habitat degradation, as generally explained and applicable in the “General Indirect Effects” section.
The positioning of the Belding’s savannah sparrow’s preferred nesting habitat (upper marsh areas
associated with pickleweed) may render it more vulnerable to indirect threats than are other marsh
birds. These upper, peripheral areas of the marsh tend be closer to developed areas, and more likely to
be used for recreational access in and throughout marsh areas. Human disturbances resulted in
flushing by Beldmg’s savannah sparrows anywhere between e5 to 100 meters with most birds flushing
between 20 to 40 meters (White 1986). Belding’s savannah sparrows are highly site-tenacious birds
and therefore will return to their territory in a matter of time. However, tenacity can be detrimental to a
species if nesting success is low in an area year after year. Also, flushing during nesting may induce
nest abandonment (Massey 1979). Specifically, indirect impacts to Belding’s savannah sparrow could
result from increases in human use of beach and coastal areas, associated with conversion of
agricultural areas to urban uses at the proposed Hub Park at the southeast comer of Agua Hedionda
Lagoon and the farmland at the northeast corner of Batiquitos Lagoon. The presence of machinery in
the lagoons can also pose a threat to this subspecies, as their presence and noise production can alter
foraging, breeding and nesting habits.
Urban run-off may also increase as a result of implementing the MHCP Subregional and City’s
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 230 -
Subarea Plan. In addition to increased peak flows, increase in impervious surfaces associated with
urbanizatibn can result in: 1) stream bed scouring and habitat degradation; 2) shoreline erosion and
stream bank widening; 3) loss of aquatic species; 4) decreased baseflow (USEPA 1999). Run-off may
pose numerous threats to the environment as discussed in the “General Indirect Effects” section.
Specific to Belding’s savannah sparrows, habitat degradation, impacts to water resources and changes
in prey availability may have indirect impacts to the subspecies. Alterations to the hydraulic regime of
salt marshes and degradation of water quality (dredging, non-point source run-off) may result in type
conversion of SaZicomia salt marsh by allowing fresh water-tolerant plant species to displace
SaZicomia. Water quality may affect nutritional quality of the salt marsh plants, altering abundance
and diversity of salt marsh insects preyed upon by sparrows (Vince and Valiela 1981). Contaminants
that may affect aquatic organisms in the lagoon may be carried to the lagoon by storm water runoff
from throughout the watershed. Developed areas are sources of non-point source pollution.
Development also increases the amount of impervious surface in the watershed, increasing the velocity
and volume of storm water runoff, thus exacerbating conveyance of non-point source pollution in
storm water runoff. Therefore, development throughout the MHCP planning area may affect
Belding’s savannah sparrows and their lagoon habitat.
The Subarea plan provides a basis for the conservation of this species and its associated habitats by
requiring the following:
1.
2.
3.
4.
5.
6.
7.
The long-term preserve management plan shall provide area specific management directives
for the major nesting areas at Agua Hedionda and Batiquitos Lagoons, including specific
adaptive management measures to address water quality and protect against detrimental edge
effects from adjacent development, recreational impacts, and other direct and indirect impacts.
As part of the project review process (e.g., CEQA) for individual projects within the MHCP
area, a qualified biologist possessing a Section 10(a)l(A) research permit for this species must
survey all areas containing potentially suitable habitat (salt marsh, mudflats, and coastal
strands) using approved survey protocols. Surveys shall occur prior to any proposed impact
regardless of location inside or outside of the ITA. Surveys shall be conducted when impacts
could occur as a result of direct or indirect impacts by placement of the project in or adjacent to
occupied or potentially suitable habitats.
Implement wetland mitigation standards that require a minimum 4: 1 replacement ratio for
unavoidable impacts to occupied habitat for this species, with particular emphasis on restoring
upper marsh zones preferred by this species. Control recreational use by humans within
pickleweed habitats to reduce trampling.
Manage occupied areas to control activities that degrade Belding’s Savannah sparrow habitat,
including human disturbance, filling and dlking of salt marsh habitat, predation of adults and
nests by introduced feral and domestic animals (e.g., dogs and cats), adverse changes in water
level, water quantity and quality, and introduction of pesticides and other contaminants into
preserve wetlands.
As mitigation for project impacts, enhance, restore, or create salt marsh habitat within the
preserve to allow for the expansion of Belding’s Savannah sparrow populations into new
locations.
Protect upland buffer areas to minimize edge effects. Buffer areas should be a minimum of 50
feet and up to 100 feet wide where possible.
Appendlx E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the Belding’s savannah sparrow)
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 23 1 -
dependent on estuarine habitats. These measures are intended to minimize indirect impacts to
rails and other estuarine species. Measures include regulation of adjacent land use, recreational
access, mosquito control, noise, vehicle access, potential pollutants, access during breedmg
season, camping and picnicking; area-specific management measures including fencing,
animal and plant pest control, habitat enhancement andor creation, trash removal, erosion
control, maintenance of tidal flushing; monitoring of covered species populations, biodiversity,
habitat area, effect of recreation on wildlife, pest animal and plant populations, use by
migratory birds, and success of restoration efforts; and development of public awareness
program including public participation in management, development of community outreach
programs, and improvement of trails and facilities to focus public access.
Management measures will focus on minimizing edge effects; controlling invasive, nonnative plants;
maintaining salt marsh hydrology and water quality; and protecting salt marsh habitat from physical
disturbances. Management measures may also include a predator control program and the
enhancement or restoration of salt marsh habitat. The long-term preserve management plan shall
provide area-specific management hrectives for the major nesting areas at Agua Hedionda and
Batiquitos Lagoons, including specific adaptive management measures to address water quality and
protect against detrimental edge effects from adjacent development, recreational impacts, and other
direct and indirect impacts. Such management will begin initially for all areas with documented
Belding’s savannah sparrows except one and any new populations will be managed per the MHCP
standards.
Conclusion
We anticipate the MHCP Subregional Plan and the City’s Subarea Plan will directly and indirectly
affect this species as described above. However, all of the lagoon habitat which includes the major
populations and critical locations will be 100 percent conserved. The Belding’s savannah sparrow will
also benefit from the conditions for estuarine species and the no-net-loss of wetland policies. The
MHCP Subregional Plan and City’s Subarea Plan will provide monitoring and management of this
species that will detect and minimize negative impacts that are affecting Belding’s savannah sparrow.
The City and California Department of Fish and Game will provide management and monitoring
initially for all but one location point of this species and once funding is available, will manage and
monitor all locations. Additionally, this species should benefit from the connected preserve system
that will be managed and monitored in the City and throughout the MHCP in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan, which
will further reduce the indirect effects and benefit the species. After reviewing the current status of this
species, the environmental baseline for the action area, the effects of the proposed action, and the
cumulative effects, it is the Service’s biological opinion that the h4HCP Subregional Plan and the
City’s Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual Belding’s savannah sparrows could
be taken in the form of harm in association with temporary habitat loss due to lagoon maintenance or
enhancement projects as a result of the City’s subarea plan. However, this number is expected to be
low (no more than two) because the City will be conserving 100 percent of the species habitat, both
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 232
major populations and critical locations will be conserved, and the conditions for estuarine species, no-
net-loss of wetlands, and critical location policies will be implemented.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 233
Passerculps sandwichensis rostrutus (Large-billed savannah sparrow)
Status of the Species
Listing Status
The large-billed savannah sparrow is a California Department of Fish and Game special concern
species, but is not federally listed.
Species Description
Passerculus sandwichensis rostratus is one of 17 subspecies of P. sandwichensis. In general, this
subspecies differs from other subspecies of savannah sparrow in its larger size, paler general
coloration, less distinct marlungs, less breast streaking, and larger bill (Rising and Beadle 1996). In
basic plumage the nape, back and rump are brownish or grayish, and streaked to varying degrees. The
crown is usually with a pale beige stripe, except the salt marsh populations (Wheelwright and Rising
1993). They have a thin yellow eye stripe. Wing bars are absent. Throat, breast, and belly are whitish
to beige with brown streaking. Juvenal plumage is similar with little or no eye stripe and heavier
brown strealung on the breast.
Distribution
This subspecies breeds along the Sea of Cortez, Mexico (Grinnell and Miller 1944) especially in the
marshes in the delta of the Colorado River (Unitt 1984). Some large-billed savannah sparrows are
resident, but others migrate (now rarely) north or northwest to California or south along both coasts of
Baja California, Mexico (Wheelwright and Rising 1993). The large-billed savannah sparrow is a
winter visitor to the Salton Sea and the southern Pacific coast of California.
Habitat Afinity
Large-billed savannah sparrows generally winter in salt marsh, mud flats, and low coastal strand
vegetation, however they can be found in a variety of open habitats, including sparsely vegetated
habitats on xeric islands (Wheelwright and Rising 1993). They frequent areas dominated by
Salicomia (pickleweed), Allenrolfeu, Suaedu, Atriplex, and Distichlis (Wheelwright and Rising 1993),
but formerly occupied a variety of habitats in southern California including beaches, wharves, and city
streets, in addition to marshes (Unitt 1984).
Life History
As a species, savannah sparrows are diurnally active throughout the year. They eat mostly grass and
other seeds, insects, snails, and spiders. Invertebrates predominate in breeding season and seeds are
more important remainder of year. They scratch and glean on the ground, and pick food directly from
low plants (Bent 1968). Cover is largely provided by herbage in grasslands, wet meadows, Salicomia
wetlands, and by associated scattered shrubs and rocks. Savannah sparrows require dense ground cover
in breeding season. In winter, they seek similar cover in a variety of moist and dry grasslands,
croplands, and in low vegetation along beaches and shorelines. They nest in a hollow on ground and
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 234
are usually concealed by overhanging vegetation. They build cup nests of grasses, sedges and
Salicomia, with an inner lining of fine grasses, rootlets, and hairs (Harrison 1978). Savannah sparrows
have been observed bathing and drinking (Norris 1960, Bartholomew and Cade 1963), but can survive
on a &et of seeds without drinking water (Bartholomew 1972). They breed mostly in dense, moist
grasslands, wet meadows, and Salicomia wetlands, with or without scattered shrubs or clumps of tall
herbs. In winter they occupy moist and dry grasslands, but prefers dense, short ground cover.
Savannah sparrows will also use low vegetation in croplands as well as beaches and shorelines.
Wintering populations arrive from August to October, depending upon the subspecies, and depart in
April or May. Montane breeding populations mostly move downslope to winter. Savannah sparrows
breed from April into July, with a peak in May and June. They lay 2-6 eggs per clutch and often have
two broods. Incubation lasts 10-13 days and the altricial young fledge in 7-14 days. Incubation and
brooding are accomplished mostly by the female (Bent 1968, Harrison 1978, Ehrlich et al. 1988).
Savannah sparrows are subject to predation by hawks, snakes, and small mammals. They may be
sernicolonial, polygynous, roost in small groups on ground, or form small flocks in winter, especially
in saline emergent wetlands (Ehrlich et al. 1988).
Population Trend
Grinnell and Miller (1944) noted that this subspecies was “common within restricted winter habitat.”
However, by the late 1970s and early 1980s, Garrett and Dunn (1981) noted that this subspecies had
become “rare to uncommon” at the Salton Sea, and almost unrecorded on the coast. They also noted
that this subspecies might have been overlooked to some extent. Unitt (1984) also noted that this
subspecies was once common but has “virtually ceased to occur on the coast of California” probably
due to “radical habitat changes in the Colorado Delta.” Currently, the subspecies occurs in very small
numbers along the coast (e.g., 3 were recorded on the San Diego Audubon Christmas Bird Count in
2002; National Audubon Society 2002).
Threats
The large-billed savannah sparrow’s decline is attributed to breeding habitat alteration in the Gulf of
California and lower Colorado River, as well as modification of wintering habitats in California (Unitt
1984).
Environmental Baseline
Within the MHCP planning area, large-billed savannah sparrow are expected to occur throughout the
planning area in salt marsh, mudflat, and low coastal strand vegetation during the winter. There are no
documented locations for large-billed savannah sparrow in the MHCP planning area. 280 acres of
suitable habitat (southern coastal salt marsh and mudflat vegetation) exists in the following MHCP
participating cities: Carlsbad, Encinitas, Oceanside, and Solana Beach. There are no major populations
within the MHCP planning area, however, the Agua Hedionda, Batiquitos, and San Elijo lagoons are
considered critical wintering locations for this species in the MHCP planning area.
The City includes approximately 151 acres of coastal salt marsh habitat in and along Buena Vista,
Agua Hedionda, and Batiquitos lagoons. In addition to coastal salt marsh in Carlsbad, the subregion
supports approximately 133 acres of suitable habitat, at the mouth of the San Luis Rey River (4 acres),
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 235
and the remainder at San Elijo Lagoon.
The current status of this subspecies is not fully known within the Subarea. We anticipate that the
large-billed savannah sparrow occurs in very small numbers in and around southern coastal salt marsh
habitats in the Subarea.
Effects of the Action
Direct Efects
The MHCP Subregional Plan has no conditions of coverage for this species. However, this species
will benefit from the conditions of coverage for the Belding’s savannah sparrow. The MHCP
Subregional Plan will have little to no direct impacts to large-billed savannah sparrow because all of
the lagoons where the species occurs and where the critical locations are located, will be 100 percent
conserved. In addition, this species is provided even greater protection through the conditions for
estuarine species in Appendix E of MHCP Volume 2 and the no-net-loss of wetland policy.
Buena Vista, Agua Hedionda, and Batiquitos Lagoons support approximately 934 acres of estuarine
and coastal salt marsh habitat (151 acres of coastal salt marsh habitat and 783 acres of estuarine
habitat). Of this amount, approximately 917 acres (98 percent) are in the preserve [777 acres of
estuarine (99 percent) and 140 acres (93 percent) of coastal salt marsh]. There are approximately 5.5
acres of open water in Batiquitos Lagoon and 3 acres of open water in Agua Hedionda Lagoon
associated with the Interstate 5 right-of-way, which are not included in the preserve since the City does
not have ultimate control of these areas. The State Route 101 and railroad rights-of-way across Buena
Vista Lagoon are also not included in the preserve. There are no projects proposed for this area,
however, impacts may occur in the future in the right-of-ways due to projects such as road widening
which would be beyond the control of the City. Such impacts would be analyzed and permitted under
a dfferent mechanism than the MHCP. 339 acres of southern coastal salt marsh and freshwater marsh
vegetation communities constitute potential habitat for white-faced ibis. A small amount of additional
habitat in the lagoons are also technically not in the mapped area of the preserve, however, no projects
are planned for this area by the City and 100 percent conservation due to MHCP standards for
avoidance, minimization, and mitigation of wetland impacts assure no-net-loss of lagoon wetland
habitat. However, impacts can occur to such wetland communities as described in section 3.6 of
MHCP Volume 1. Since such impacts would need to be fully mitigated according to section 4.4.2 of
MHCP Volume 1, no-net-loss of function or value will occur in MHCP, although there could be a
temporal loss of such functions and values. The MHCP conditions for estuarine species and fact that
all the lagoons are in the coastal zone, also provide more protection to the lagoon areas. Due to these
standards, any losses would only be temporal and no net decrease in lagoon habitat (estuarine, salt
marsh, etc.) would occur as a result of the City’s Subarea Plan. In addition, direct take of animal
species is expected to be minimized because any areas proposed for disturbance would be avoided
where MHCP species or nests are known or found to be present.
Indirect Efects
Indirect impacts have the potential to cause significant adverse effects to large-billed savannah
sparrows. These indirect impacts include night lighting, human disturbance, depredation by domestic
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 236 -
pets, and habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
The large-billed savannah sparrow is a subspecies related to the Belding’s savannah sparrow and
shares common biological traits including general life history and habitat affinity. The subspecies
differ by physical appearance and migratory behavior. Belding’s savannah sparrows are year-round
residents, while large-billed savannah sparrows are winter visitors. Because of their biological
similarity, plan impacts to large-billed savannah sparrows are expected to be similar to impacts to
Belding’s savannah sparrows. Human disturbance resulted in flushing by savannah sparrows
anywhere between <5 to 100 meters with most birds flushing between 20 to 40 meters mte 1986).
Savannah sparrows are highly site-tenacious birds and therefore will return to their territory in a matter
of time. However, tenacity can be detrimental to a species if nesting success is low in an area year
after year. Also, flushing during nesting may induce nest abandonment (Massey 1979). Specifically,
indirect impacts to the large-billed savannah sparrow could result from increases in human use of
beach and coastal areas, associated with conversion of agricultural areas to urban uses at the proposed
Hub Park at the southeast comer of Agua Hedionda Lagoon and the farmland at the northeast comer of
Batiquitos Lagoon. The presence of machinery in the lagoons can also pose a threat to species, as their
presence and noise production can alter foraging, breeding and nesting habits.
Urban run-off may also increase as a result of implementing the MHCP Subregional Plan and City’s
Subarea Plan. In addition to increased peak flows, increase in impervious surfaces associated with
urbanization can result in stream bed scouring and habitat degradation, shoreline erosion and stream
bank widening; loss of aquatic species, and decreased baseflow (USEPA 1999). Run-off may pose
numerous threats to the environment as discussed in the “General Indirect Effects” section, Specific to
savannah sparrows, habitat degradation, impacts to water resources and changes in prey availability
may have indirect impacts to the subspecies. Alterations to the hydraulic regime of salt marshes and
degradation of water quality (dredging, non-point source run-off) may result in type conversion of
Sulicomiu salt marsh by allowing fresh water-tolerant plant species to displace Salicomia. Water
quality may affect nutritional quality of the salt marsh plants, altering abundance and diversity of salt
marsh insects preyed upon by sparrows (Vince and Valiela 198 1). Contaminants that may affect
aquatic organisms in the lagoon may be carried to the lagoon by storm water runoff from throughout
the watershed. Developed areas are sources of non-point source pollution. Development also
increases the amount of impervious surface in the watershed, increasing the velocity and volume of
storm water runoff, thus exacerbating conveyance of non-point source pollution in storm water runoff.
Therefore, development throughout Carlsbad may affect large-billed savannah sparrows and their
lagoon habitat.
The Subarea plan provides a basis for the conservation of this species and its associated habitats by
requiring the following:
1. The long-term preserve management plan shall provide area specific management directives
for the potential nesting areas at Agua Hedionda and Batiquitos Lagoons, including specific
adaptive management measures to address water quality and protect against detrimental edge
effects from adjacent development, recreational impacts, and other direct and indirect impacts.
Appendix E (Conditions for estuarine species) of the MHCP includes measures that must be
implemented to ensure coverage of species (including the large-billed savannah sparrow)
dependent on estuarine habitats. These measures are intended to minimize indirect impacts to
2.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 237 -
rails and other estuarine species. Measures include regulation of adjacent land use, recreational
access, mosquito control, noise, vehicle access, potential pollutants, access during breeding
season, camping and picnicking; area-specific management measures including fencing,
animal and plant pest control, habitat enhancement and/or creation, trash removal, erosion
control, maintenance of tidal flushing; monitoring of covered species populations, biodiversity,
habitat area, effect of recreation on wildlife, pest animal and plant populations, use by
migratory birds, and success of restoration efforts; and development of public awareness
program including public participation in management, development of community outreach
programs, and improvement of trails and facilities to focus public access.
We anticipate that this subspecies will benefit from management measures required for coverage of
Belding’s savannah sparrow.
Management measures will focus on minimizing edge effects; controlling invasive, nonnative plants;
maintaining salt marsh hydrology and water quality; and protecting salt marsh habitat from physical
disturbances. Management measures may also include a predator control program and the
enhancement or restoration of salt marsh habitat. The long-term preserve management plan shall
provide area-specific management directives for the potential nesting areas at Agua Hedionda and
Batiquitos Lagoons, including specific adaptive management measures to address water quality and
protect against detrimental edge effects from adjacent development, recreational impacts, and other
direct and indirect impacts. Such management will begin initially for all lagoons in the City by the
California Department of Fish and Game.
Conclusion
We anticipate the MHCP Subregional Plan and the City’s Subarea Plan will directly and indirectly
affect this species as described above. However, all of the lagoon habitat which includes the critical
locations will be 100 percent conserved. The large-billed savannah sparrow will also benefit from the
conditions for Belding’s savannah sparrow and estuarine species and the no-net-loss of wetland
policies. The MHCP Subregional Plan and City’s Subarea Plan will provide monitoring and
management of this species that will detect and minimize negative impacts that are affecting large-
billed savannah sparrow. The City and California Department of Fish and Game will provide
management and monitoring initially for all the lagoons and any newly found locations. Additionally,
this species should benefit from the connected preserve system that will be managed and monitored in
the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline for
the action area, the effects of the proposed action, and the cumulative effects, it is the Service’s
biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to
jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual large-billed savannah sparrows
could be taken in the form of harm in association with temporary habitat loss due to lagoon
maintenance or enhancement projects as a result of the City’s subarea plan. However, this number is
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 238
expected to be low (no more than two) because the City will be conserving 100 percent of the species
habitat, both critical locations will be conserved, and the conditions for Belding’s savannah sparrow,
estuarine species, no-net-loss of wetlands, and critical location policies will be implemented.
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 239
Cnemidophorus hyperythrus beldingi (Orange-throated whiptail)
Status of the Species
Listing Status
The orange-throated whiptail is a State of California protected and special concern species with a
California Natural Diversity Database rank of G5T2S2. There is no Federal listing for this subspecies.
Species Description
Cnernidophorus hyperythrus beldingi is a moderate-sized gray, reddish brown, dark brown, or black
lizard with five to seven pale yellow or tan stripes (Walker and Taylor 1968, Stebbins 1985, Rowland
1992). The top of the head has a single, fused frontoparietal scale (Rowland 1992), and is yellow-
brown to olive gray (Jennings and Hayes 1994). Undersurfaces are yellowish white, often with gray or
bluish slate on the belly; adults have varying degrees of red-orange wash (Stebbins 1985) that may
occur on all undersurfaces (Rowland 1992). The later is especially prominent on the throat and chest
in breeding males. In hatchlings and juveniles, the tail is a highly visible bright blue (Rowland 1992).
Distribution
The current range includes southwestern California and Baja California. In California, orange-throated
whiptail’s range from the southern edges of Orange County (near Corona del Mar) and San Bemardino
County (near Colton) southward to the Mexican border. They are located on the coastal slope of the
Peninsular Ranges, and extend from near sea level to 1,040 meters (Jennings and Hayes 1994). The
distribution of Reticulitemes hesperus (western subterranean termite), the orange-throated whiptail’s
primary prey item, limits the distribution of the whiptail, where apparently suitable habitat continues.
For example, the Peninsular Mountain Range in Riverside and San Diego Counties where R. hesperus
is limited to its slopes, possibly restricts eastward and altitudinal expansion of the whiptail populations.
Similarly, in San Bernardmo, the restriction of R. hesperus to the lower slopes of the transverse and
Peninsular Mountain Ranges, and their local scarcity, possibly prevents eastward expansion of
whiptails in that county. The fact that R. hesperus are abundant in Los Angeles and Orange counties,
but whiptails are conspicuously absent from these counties, despite the frequency of what appears to be
suitable whiptail habitat, suggests that urban, suburban and agricultural development activities serve, in
part, as effective dispersal barriers @udek and Associates 2000b).
Habitat Afinity
Orange-throated whiptails use chaparral, non-native grassland, coastal sage scrub, juniper woodland
and oak woodland habitats as well as alluvial fan scrub and riparian areas. This subspecies is
presumably tied to perennial vegetation because termites are its major food source (Bostic 1966a).
California buckwheat or flattop buckwheat (Eriogonurn fasciculaturn), a colonizing species of
disturbed, sandy soils, is an important indicator of favorable habitat for whiptails (McGurty 1981,
Rowland 1992). The presence of California buckwheat generally indicates a particular amount of
inter-shrub spacing (10 to 40 percent bare ground cover) apparently required for foraging and
thermoregulatory behavior of this subspecies (McGurty 198 1, Rowland 1992). California buckwheat
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 240
is known to commonly occur in both coastal sage scrub and chaparral. California sagebrush
(Artemisia‘ culifomicu), black sage (Salvia melliferu), and white sage (Salvia upiuna) are some of the
other plant species that may fill the perennial plant requirement for the whiptail. Friable soil appears to
be a necessary requirement for excavating burrows and hiding eggs (Bostic 1965). Soil grain size
preference data clearly suggest that whiptails choose only the two finest grain sizes in which to bury
(Brattstrom 1989). However, the whiptail may choose to bury in loose soil aprons brought up from the
sub-surface by rodents, in an otherwise large grain exposure (Brattstrom 1989).
Life History
Bostic (1966a) found that Orange-throated whiptails feed primarily on prey of a secretive nature and
low activity (e.g., ants), depending primarily on chemo-reception when hunting such prey. When
hunting prey of intermediate or high activity (e.g., Lepidopterans), vision is most often employed. In
San Diego County and Baja California, Mexico, the subterranean termite, Reticulifemzes hesperus
comprises over 85 percent of all prey consumed. Bostic’s (1966a) data indicates that termites
comprised 72 percent-92 percent of the whiptail diet, with peak consumption occurring simultaneously
with the swarming of reproductives in April. In late summer, when termites migrate deep into the soil
to avoid high surface temperatures, alternate prey items dominate the whiptail’s &et. No significant
differences in diet between the sexes or between adults and juveniles was found (Bostic 1966a). The
most important alternate prey item for the orange-throated whiptail is the spider (Armedia), which was
found by Bostic (1966a) to be the next most abundant prey item after termites. Additional alternate
prey items, listed in order of importance are: Orthopterans, cockroaches (Bluttidae), short-horned
grasshoppers (Acrididae), long-homed grasshoppers, crickets; Lepidopterans, pyralid moths
(Pyrulidae) and their larvae; Neuropterans, antlion larvae; adult Coleopterans, their larvae and pupae,
ground beetles (Carabidae) and darkling beetles (Tenebrionidae); and Homopterans, leafhoppers
(Cicudellidae) and planthoppers (Fulgoridae).
Whiptails are diurnal, but they are also bimodal, spending the warmest portion of the day in shade or
an underground retreat mlstead 1957). During relatively low early morning temperatures, whiptails
move slowly while foraging and frequently stop to bask (Bostic 1966b). During this time, whiptail
activity is confined to open or sparsely covered grass areas between bushes. Bashng becomes
infrequent and of short duration as mid-morning temperatures increase and foraging largely occurs in
shaded or semi-shaded areas around bushes, with travel in open areas occumng very rapidly (Bostic
1966a). Few whiptails are observed foraging as mid-day temperatures increase. Most retreat to cooler
areas (e.g., rodent burrows, shade beneath bushes, or they excavate shallow retreats in the substrate).
Adult whiptails usually enter into hibernation in late July through most of September, while immatures
enter into hibemation in December (Bostic 1966a). Hibernation, and likely oviposition sites, occur on
well isolated, south facing slopes (Jennings and Hayes 1994). Unlike several species in the genus
Cnemiduphurus, orange-throated whiptails do not reproduce parthenogenetically. Males are
reproductively active from the first week of April through the first week of July based on the presence
of enlarged testes during this period. Whiptails were generally found to reach maturity in the spring
following hatching in the previous summer based on examination of the gonads and accessory
reproductive structures of the dissected lizards. In yearlings, reproductive potential is lower than in
adults of two years of age or older. Bostic (1966~) estimated average clutch size to be 2.3 eggs. It
appears that adult females (2 years of age or older) deposit one clutch of eggs in June and another in
Carlsbad Subarea Plan Biological and Conference Opinions (WS-SDG-847.4) 24 1 -
mid-July Postic 1966~). In contrast, one clutch per season is probably the rule for yearlings which
deposit their eggs in late June through mid-July (Bostic 1966~).
Bostic (1965) recorded an average home range of 0.1 1 acre for adult orange-throated whiptails, which
is considerably smaller than the average home ranges of larger species of Cnemidophoms @udek and
Associates 2000b). Females have significantly larger home ranges than males. The mean home range
size for females was approximately 2.1 times larger than the mean home range for males.
Consequently, female home ranges extensively overlap and superimpose with each other as well as
overlap male ranges. “Overlap, but not superimposition of male home ranges was also recorded”
(Bostic 1965).
Population Trend
Cooper et al. (1973) reviewed the status of C. h. beldingi in California in the course of an assessment
of the Santa Margarita Ecological Reserve and environs, and concluded that this taxon was depleted.
McGurty’s (1980) data suggested that C. h. beldingi had been extirpated from 60 percent of its historic
range at the time of his survey (Le., 1980). Jennings and Hayes (1994) compared McGurty’s data to
aerial photographs in 1990 and estimated that 75 percent of the historic range of C. h. beldingi no
longer supported this subspecies. The population trend of orange throated whiptails in the Subarea and
MHCP is unknown due to a lack of survey effort.
Threats
Habitat destruction is likely the major cause of the decline of orange-throated whiptail populations.
Despite what appears to be abundant suitable whiptail habitat, urban and agricultural development may
serve as effective dispersal barriers (Bostic 1966b). Argentine ants (Zrdomyrmex humilis) are an
invasive exotic species known to displace many native insects, and may influence the food base of
orange-throated whiptails (Jennings and Hayes 1994). Excessive ,prescribed burning can lead to
increased exposure to predation due to mdfication of the canopy profile, and can ultimately lead to
type conversion from coastal sage scrub and chaparral to non-native grassland (McGurty 1981). In
addition, repeated reduction of normally abundant woody fuels has a direct effect on western
subterranean termite (Reticulitermes hespems) presence, the nearly exclusive food-prey source of
orange-throated whiptails. Further threats include irreversible habitat destruction resulting from
land-filling or artificial channelization of natural drainage bottoms, which likely serve as foraging and
dispersal areas for this species (Jennings and Hayes 1994).
Environmental Baseline
Within the MHCP Subregional Plan, orange-throated whiptails have been documented in Oceanside,
Carlsbad (Carlsbad Highlands, Aviara, and east La Costa), north and south Encinitas, and southwest
and east Escondido (near Harmony Grove and San Pasqual Valley). There are no major populations or
critical locations in the MHCP planning area, although substantial populations are expected throughout
some of the larger blocks of habitat in northeast Escondido, north Oceanside, and south San Marcos.
Within the City of Carlsbad, approximately 7,390 acres of the habitat within the Subarea have the
potential to support orange-throated whiptails based on this subspecies’ habitat affinities. Portions of
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 242 -
these habitat types may not be suitable for this subspecies (i.e. >50 percent vegetative cover in sage
scrub), thirefore the amount of suitable habitat will likely be less. Population estimates and location
data have not been completed for this subspecies due to a lack of survey effort. However, observations
of orange-throated whiptails have been documented within the Subarea in Core Areas 5 and 7, and
Linkage F and are likely to occur in Core Area 3.
Effects of the Action
Direct Efects
The MHCP Subregional Plan will directly impact this species and has no conditions of coverage for
this species. Sixty percent (55 of 92) known location points will be conserved by the MHCP.
However, orange-throated whiptail are not well represented by species points, thus our analysis must
use suitable habitat as the unit of measure. The MHCP Subregional Plan will conserve 12,163 acres
(66 percent) of the primary orange-throated whiptail habitat of which 71 percent is within the BCLA.
The City of Carlsbad‘s preserve design provides for conservation of 3,157 acres (52 percent) of
suitable habitat, with anticipated with anticipated impacts to 1,518 acres (48 percent) of habitat as a
result of this plan. Direct effects to this subspecies will result from the elimination of suitable habitat
with an unknown number of orange-throated whiptails present.
Indirect Efects
Indirect impacts are anticipated and have the potential to cause significant adverse effects to orange-
throated whiptails. These indirect impacts include night lighting, human disturbance, depredation by
domestic pets, and habitat degradation, as generally explained and applicable in the “General Indirect
Effects” section.
Specifically, this subspecies may be particularly susceptible to Argentine ants. In addition to possible
depredation on the orange-throated whiptail by the ants, the ants also likely depredate the termites upon
which the whiptail depends.
Implementation of the MHCP and City’s Subarea Plan may also indirectly affect this subspecies by
increasing the amount of lighting within the planning area. City lights are known to upset the behavior
of snakes and other nocturnal animals (Lieberman 2002) and may have adverse impacts to this
subspecies near developed areas.
Other indirect effects to this subspecies may result from an increase in road-kill impacts as
development and associated road networks fragment portions of the orange-throated whiptails habitat.
Fragmentation of the orange-throated whiptail’s habitat can induce dispersal of the subspecies. This
subspecies could also be impacted by collection for pets. The Subarea plan provides a basis for the
conservation of this subspecies and its associated habitats. Specifically, Table 9 of the Subarea plan
states:
0 Manage preserve areas to restrict activities that would degrade habitat; control
predators. If opportunities arise, consider establishing a relocation program (possibly
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 243
in Core Area 3 or 7) to initiate new populations or enhance and maintain existing
populations. Provide management measures which facilitate movement between
populations within the City as well as to regional linkages.
0 Conserve approximately 2,000 acres of coastal sage scrub, 700 acres of chaparral and
350 acres of southern maritime chaparral where this species may occur.
W Maintain linkages between populations in Core Area 7 and areas to the southeast.
In addition, management will begin initially for approximately half of the areas that have or once had
documented orange-throated whiptails and any new populations will be managed per the MHCP
standards.
Conclusion
We anticipate the MHCP Subregional Plan and City’s Subarea Plan will directly and indirectly affect
this species through habitat loss from development. However, 52 percent of orange-throated whiptail
habitat will be conserved by the MHCP and City’s subarea plan combined and there are no major
populations or critical locations of this species in the MHCP planning area. In addition, the MHCP
Subregional Plan and City’s Subarea Plan will provide monitoring and management of this subspecies
that will detect and minimize negative impacts that are affecting orange-throated whiptail. This
species should also benefit from the connected preserve system that will be managed and monitored in
the City and throughout the MHCP in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline for
the action area, the effects of the proposed action, and the cumulative effects, it is the Service’s
biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to
jeopardize the continued existence or recovery of this species.
Amount or Extent of Take
The Service anticipates that an undetermined number of individual’orange-throated whiptails within a
maximum of 1,176 acres of coastal sage scrub, 292 acres of chaparral, and 50 acres of southern
maritime chaparral could be taken in the form of harm as a result of the City’s subarea plan. The
incidental take is expected to be in the form of habitat loss. However, mortality to the species will be
minimized by avoiding impacts to habitat within the Preserve during the breeding season due to the
coastal California gnatcatcher utilizing similar habitat. This level of anticipated take is not likely to
jeopardize the continued existence and recovery of the species.
244 -
SPECIES-BY-SPECIES EVALUATIONS
SPECIES &OM TABLE 2: These are species which the City will not receive coverage for
immediately upon approval of their permit. The City’s coverage is contingent on Other MHCP
Subarea Plans being Permitted as described for each species below.
Acanthomintha ilicifolia (San Diego thorn-mint)
Status of the Species
Listing Status
San Diego thornmint was federally listed as threatened on October 13, 1998 (63 FR 54938), and
State listed as endangered in January 1982. Critical habitat has not been proposed for this
species, and a recovery plan has not been prepared. A detailed account of the status, distribution,
taxonomy, ecology, and reproductive characteristics of San Diego thornmint is presented in the
final rule, which is hereby incorporated by reference (US. Fish and Wildlife Service 1998a).
The State of California Department of Fish and Game has listed this species as endangered in
January 1982. The California Native Plant Society has placed this species on list 1B with a R-E-
D (Rarity-Endangerment-Distribution) code of 2-3-2, and a California Natural Diversity Data
Bank ranking of GlS1.1.
Species Description
Acanthomintha ilicifolia is an annual aromatic herb in the Lamiaceae (mint) family. A. ilicifolia
is a low annual, with stems branching from the base or sometimes simple, 5-15 centimeters. The
leaves are 5-15 millimeters long, cuneately narrowed; bracts orbicular or broadly cordate; calyx
5 millimeters long; corolla 12 millimeters long, white except the lobes of the lower lip rose and
the palate cream color; upper lip erect, 3-4 millimeters long, entire, strongly concave and
somewhat galeate; lower lip spreading, 5-6 millimeters long, 3-lobed, bearing a tuft of prominent
hairs toward the base within; anther bearing stamens 2, the upper pair abortive; anthers minutely
papillate, otherwise glabrous; styles glabrous (Abrams 195 1). A. ilicifolia can be distinguished
from other members of the genus by its flower, which has hairless anthers and style. The tubular,
two-lipped corollas (petals) are white with rose markings on the lower lip. The only other
Acanthomintha species occurring in southern California (A. obovata) has 4 fertile, woolly, or
pubescent anthers and is known from Ventura County north (Bittman 1991).
Distribution
San Diego thornmint is a clay soil endemic (Beauchamp 1986, Bittman 1991) found only in San
Diego County, California south to San Telmo in northern Baja California, Mexico. In San Diego
County, the species is known from Carlsbad and San Marcos south to Sweetwater and Otay
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Mesa, and east to Alpine (Beauchamp 1986, U.S. Fish and Wildlife Service 1998a). In the
Subarea, populations are found north of Palomar Airport, south and east of Agua Hedionda, La
Costa area. Bittman (1991) reported the elevational range for this species as 25 to 3500 feet (8 to
1000 m), however, J.D. Jokerst reported that it occurred below 900 meters.
Habitat AfSinity
San Diego thornmint is generally associated with vernal pools, grassland habitats, and widely
scattered, discrete open patches in coastal sage scrub and chaparral. San Diego thornmint occurs
on heavy, vertisol clay substrates, which are often derived from metavolcanic substrates (Munz
1974, Bittman 1991, US. Fish and Wildlife Service 1998b). It is also associated with gabbro
soils which are derived from igneous rock and may occur in calcareous marine sediments (U.S.
Fish and Wildlife Service 1998b).
Life History
San Diego thornmint flowers from April to May (Munz 1974, Bittman 1991) and remains erect
and retains its distinct shape well into the dry season (Reiser 1996). San Diego thornmint is an
outcrosser that is insect pollinated (Wyatt 1983) and may rely on animal vectors, in part, for seed
dispersal (Ogden 2000). While this annual can be raised from seed, suitable friable clay
microhabitats are uncommon and place strict limitations on the establishment of new populations
(Reiser 1996).
Population Trends
About 40 percent of the 52 historic populations in the United States have been extirpated (U.S.
Fish and Wildlife Service 1998a). Currently there are about 150,000-170,000 individuals in 32
populations in the United States, ranging from Carlsbad and San Marcos east to Alpine and south
to Otay Mesa in San Diego County (Bittman 1991, Reiser 1996, U.S. Fish and Wildlife Service
1998a, Ogden 2000). This species occupies an estimated 156 hectares (400 acres). About 60
percent of the reported individuals are concentrated in four populations (Sycamore Canyon,
Slaughterhouse Canyon, and two populations on Viejas Mountain). Other populations occur in
Carlsbad, Encinitas, San Marcos, Sycamore Canyon, Poway, the Lake Hodges area, El Capitan,
and Jamul (Ogden 2000). At least nine sites in Baja California are known to have recently
supported San Diego thornmint, however, the current status of the species in Mexico is uncertain.
Threats
San Diego thornmint populations are adversely affected by trampling and off-road vehicle traffic,
including bicycles (U.S. Fish and Wildlife Service 1998a). It is susceptible to local extirpation
by catastrophic fire and surface disturbance (Ogden 2000) and is threatened by development,
agriculture, grazing, and competition by non-native plant species (U.S. Fish and Wildlife Service
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199 8 a).
Environmental Baseline
San Diego thornmint is found in all of the cities within the MHCP except Solana Beach. There
are 22 locations points known within the MHCP planning area. Major populations occur in
Carlsbad, as described below, in Encinitas at Quail Botanical Gardens and Lux Canyon and
vicinity, in San Marcos and Vista at San Marcos West, and Escondido. This is a total of eight
major population areas within the MHCP. In addition to these major populations, there is one
population of San Diego thornmint in the City of Carlsbad that was recently discovered on the
preserve associated with the Villages of La Costa (the Greens) property (pers. comm. Markus
Spiegelberg). One other population exists on county property northeast of the intersection of
Palomar Airport Road and El Camino Real, completely surrounded by the City of Carlsbad.
Of the five major populations in the City of Carlsbad, two occur on properties that have been
previously permitted; the other three are addressed by the plan. Each of the populations is made
up of a varying quantity of point locations. The northem-most population is located southwest of
the intersection of El Camino Real and College Boulevard (El Camino Real / College Blvd.).
This population is in close proximity to a hardline preserve area, however the point location is
located outside the preserve. Further investigation is needed to verify the existence of San Diego
thornmint in this preserve area. The second population is located to the southeast of the
intersection of Palomar Airport Road and Aviara Parkway (South Palomar Airport Road). This
population is made up of two point locations, both of which are not located within the preserve
design. The third population is located partially on the Carlsbad Raceway property and partially
in San Marcos (San Marcos West). Although San Diego thornmint was found on this site in
1986, it was not found in a 2001 survey. If the San Diego thornmint is still extant at this
location, it is likely in the preserve or in the City of San Marcos adjacent to the Carlsbad
Raceway property. A fourth population is located at the intersection of El Fuerte Street and
Rancho Pancho Road (North Alga Road). The status of this population is unknown at this time.
The fifth is located in the southeastern portion of the City of Carlsbad (Olivenhain). Whereas the
other populations contain closely grouped point locations, this population contains dispersed
point locations.
All of the point locations in the Olivenhain population are on previously permitted projects.
Point locations in this population have been lost to development at the intersection of La Costa
Avenue and Rancho Santa Fe Road. Another point location for San Diego thornmint occurs just
outside the preserve area between Calle Barcelona and Saucedal Via. The status of this point
location is unknown. The third subpopulation within this population is located to the south of La
Costa Canyon High school. It is made up of six point locations, two of which fall outside the
preserved area and are thought to be extirpated. The other four point locations are within the
preserve, but their current status is unknown.
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San Diego thornmint is restricted to calcareous marine sediments, clay or gabbro-derived soils
and are a5sociated with coastal sage scrub, chaparral, and grassland. The existing amount of
coastal sage scrub, chaparral, and grassland is quantifiable; however, it is difficult to estimate the
amount of habitat available for San Diego thornmint. Often patches of the appropriate habitat are
too small and localized to show up on soil or vegetation maps and therefore cannot be measured.
It is possible that other populations of San Diego thornmint will be found in the Carlsbad
subarea.
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Effects of Action
Direct Effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1.
2.
3.
4.
5.
6.
7.
- The major populations and critical locations of San Diego thorn-dnt in Carlsbad and San
Marcos must be conserved at a level consistent with the critical location policy and
managed as part of the preserve system.
Fire management plans must be implemented for all conserved populations to protect
them from frequent or high-intensity fires and fire suppression activities. Fire
management plans should include emergency access plans for conserved areas to protect
populations from fires and disturbances associated with fire suppression.
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist must survey for this species in all potential habitat
areas.
The MHCP narrow endemic policy must be applied to any population of this species,
including those already known and any found in the future.
Declining populations must be enhanced and damaged habitat restored, if determined
necessary through monitoring.
If not already established in the region by another entity, the MHCP management
program must establish a seed bank as a guarantee against extinction and to provide
source materials for conservation and research activities. A seed bank must be
established within 15 years of permit issuance. Collections should be based on
established guidelines and subject to seed availability. Collected seed should be stored at
an established seed bank facility (e.g. Rancho Santa Ana Botanic Garden or San Diego
Wild Animal Park).
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
The MHCP Subregional Plan will directly impact San Diego thornmint in all of the cities it
currently occurs except Encinitas and Escondido which will conserve all the known point
locations at 100 percent. A majority of the known species points occur within the FPA (70
percent) and will be conserved at levels of 95 to 100 percent. Points that fall outside the FPA
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will be conserved at least 80 percent due to the narrow endemics policy. The City of Oceanside is
expected to conserve 95 percent of the two locations points within the City. The City of San
Marcos is’ expected to conserve 90 percent of the four location points currently known in the
City. The City of Vista is expected to conserve at least 80 percent of the two location points
currently known in the City. Overall, 91 percent of the major populations and critical locations
of this species in the study area will be conserved under the current FPA design and all critical
locations will be 100 percent conserved. Of the eight major populations, five will be entirely
conserved within the FPA ( north of Alga Road, Quail Botanical Gardens, Lux Canyon and
vicinity, and Escondido). In addition, the MHCP Subregional Plan will conserve 3,403 acres (52
percent) of San Diego thorn-mint suitable habitat (calcareous marine sediments, clays, or gabbro-
derived soils in coastal sage scrub, chaparral and grassland).
In the City of Carlsbad, two of the three populations of San Diego thornmint located in the
subarea, but not yet permitted, will be directly impacted. These two populations (El Camino
RealKollege Boulevard and South Palomar Airport Road) do not occur in preserve areas, but
because this plant is a narrow endemic they will be impacted at no greater than 20 percent. The
third population (North Alga Road) occurs in a preserve area and will not be directly impacted.
Any additional populations found will be preserved according to the narrow endemic policy.
However, the City of Carlsbad would not receive coverage for this species until the City of San
Marcos has a valid 10(a)l(B) permit for their Subarea Plan from the Service with this species is
covered or the major and critical population in the major amendment area of San Marcos is
preserved and managed in perpetuity. In addition, the City of Carlsbad will also not receive
coverage for this species until documentation is provided that assures the above conditions,
including management and monitoring of this species in perpetuity throughout the City,
according to MHCP Volume 3 standards, can be met among the signatories to the IA (City,
Service, and/or Department). Thus, development that would adversely affect this species could
not be permitted under Carlsbad’s HMP until such coverage is received by the City. The process
for initiating coverage for species in Table 2 requires the City to document in writing that the
necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
Indirect Efsects
The populations on small or narrow preserves will encounter several potential adverse affects to
San Diego thornmint such as increased traffic from humans and their pets, run-off water and
restricted habitat for pollinators. Of these threats, increased run-off water may pose the greatest
risk to this plant. Run-off water from development could wash adjacent soils or fill into the area
where the thornmint grows, thus altering the soil conditions. The MHCP Subregional Plan
requires surveys for this species in all areas containing suitable habitat. This will insure that any,
as of yet undiscovered populations of San Diego thornmint, will be found. These indirect
impacts would be avoided and minimized by monitoring and management of this species
according to MHCP standards. However, the City would not be able to initially fund or gain
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access for management and monitoring for nearly all of the critical locations and all but two of
the other occurrences in the City until a regional funding source, or some other additional funds,
are available. Because of this, coverage for this species is not being proposed until the City of
Carlsbad can document they have access and the funds available to manage and monitor this
species as described in the MHCP Volume 3 and the OSMP.
-
Conclusion
We have concluded that the MHCP Subregional Plan and City’s Subarea Plan will directly
impact San Diego thorn-mint throughout the MHCP planning area by habitat loss from
development. However, overall 9 1 percent of all known location points, major populations, and
critical locations will be conserved and 52 percent of San Diego thorn-mint habitat will be
conserved. In addition, the MHCP Subregional Plan assures that no more than 80 percent of any
population will be impacted outside of the FPA due to the narrow endemics policy. All
remaining populations of San Diego thorn-mint will be monitored and managed consistent with
the MHCP Management and Monitoring Plan (Volume 3) and coverage for this species to the
City does not begin until the City of San Marcos receives a lO(a)(l)(B) permit with this species
covered and the City of Carlsbad can provide documentation to the Service and Department that
adequate access and funding is available. Thus, the plan will detect and minimize any negative
impacts that are affecting San Diego thorn-mint. The avoidance, minimization, andor mitigation
measures included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any
impacts that may occur to this species. This species will also benefit from the habitat that the
MHCP Subregional Plan will preserve in perpetuity. This Preserve will be adaptively managed,
per the measures included in the MHCP Subregional Plan and the City’s Subarea Plan which will
further reduce the indirect effects and benefit the species. After reviewing the current status of
this species, the environmental baseline for the action area, the effects of the proposed action,
and the cumulative effects, it is the Service’s biological opinion that the MHCP Subregional Plan
and the City’s Subarea Plan are not likely to jeopardize the continued existence or recovery of
this species.
Ambrosia pumila (San Diego ambrosia)
Status of the Species
Listing Status
San Diego ambrosia was listed as endangered on July 2,2002 (67 FR 44372). This species is
also on the California Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-
Distribution) code of 3-3-2, and a California Natural Diversity Data Bank ranlung of GlS1.1
Species Description
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San Diego Ambrosia is a clonal, perennial herb in the Asteraceae (sunflower) family. They arise
from a branched system of rhizome-like roots (U.S. Fish and Wildlife Service 1999d). This
rhizomatk perennial habit results in groupings of aerial stems, often termed clones, that are, or
at least were at one time, all attached to one another. The aerial stems are 0.5 to 3 decimeters (2
to 12 inches) rarely to 5 decimeters (20 inches) tall and densely covered with short hairs. The
leaves are 3 to 4 times pinnately divided into many small segments and are covered with short,
soft, gray-white, appressed hairs. The fruiting heads are enclosed by cup-like structures that have
no spines, although some reports note a few vestigial spines. A. pumila may be distinguished
from other species of Ambrosia in the area by its leaves which are twice divided, involucres (cup-
like structures) lacking hooked spines, and lack of longer stiff hairs on the stems and leaves (U.S.
Fish and Wildlife Service 1999d).
Distribution
San Diego ambrosia is distributed from western Riverside County and western San Diego
County, California, south in widely scattered populations along the west coast of Baja California,
Mexico, to the vicinity of CaboColonet (Munz 1974, Reiser 1996). Additional populations
occur in the central highlands of Baja California in the vicinity of Laguna Chapala near Catavinia
(Reiser 1996). Some remnant populations have been found in urbanized places such as National
City (Reiser 1996). It has also been reported from two areas in Oceanside (near El Camino Real
and near Mission Boulevard in east Oceanside).
Habitat Aflnity
San Diego ambrosia occurs in open habitats in coarse substrates near drainages, and in upland
areas on clay slopes or on the dry margins of vernal pools. It also occurs in a variety of
associations that are dominated by sparse grasslands or marginal wetland habitats such as river
terraces, pools, and alkali playas (Munz 1974, Reiser 1996). Reiser (1996) noted that San Diego
ambrosia may also occur in creek beds and willow woodlands lacking tree canopies. Dudek and
Associates (1999) found Ambrosia pumila in sandy loam textured soils, that were moderately
acidic (pH ranging from 4.48 to 5.77) and low in salinity. San Diego ambrosia has been reported
from 0-9 percent slopes on sandy or clay loams (Boling, L. 1988). At Mission Trails Regional
Park in San Diego, Ambrosia pumila occurred upon slope angles ranging from 0 to 18 percent
with the vast majority of plants occurring at slope angles of less than 5 percent (Dudek &
Associates, Inc. 1999). San Diego ambrosia generally occurs at low elevations (i.e., less than 180
meters in San Diego County) (Payne 1996). Commonly associated species include Nasella spp.,
Avena spp., Bromus spp., Centaurea melitensis, Ambrosia psilostachya, Hemizonia fasciculata,
Holocarpha virgata, Distichlis spicata, Eremocarpus setigems, and several vernal pool species.
Life History
Sexual reproduction and seed-set are not considered to be common in this taxon suggesting that
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propagation and dispersal by seed is limited. Because pollen is contained in the downward
facing male cluster and is positioned above female flower heads, Ambrosia pumila may self-
pollinate.’ Perennial Ambrosia species generally produce fewer seeds than annual species and
invest more reproductive resources in below-ground root structures. Several biotechnical reports
from transplantation efforts offer support for the lack of or low seed reproduction in the species
@udek and Associates 2000b). Ambrosia species are probably primarily wind pollinated, but
other vectors (e.g. crawling insects) are a possibility (Payne, pers. Comm. 1998). Propagation is
primarily through extensions of rhizomes indicating that each population could be a single plant
and restricted to the immediate habitat. The species propensity to reproduce asexually suggests
that the most common form of dispersal may be movement of rhizome-like structures either short
distances by growth or longer distance by flood disturbance (Boling, L. 1988, Marquez, V. 1991-
1993, and RECON 1993). Ambrosia pumila also partially relies on animal vectors for seed
dispersal. Ambrosia pumila is sensitive to seasonal conditions and variation resulting in
fluctuations in the above ground biomass. Flowers are generally present from June through
September (Munz 1974).
Population Trend
This species has been reported from 49 occurrences in the United States (CNDDB 2004). Four
were combined with other occurrences, six were based on misidentified specimens, and two that
were based on old collections have not been documented since 1936 (CNDDB 2004). Three
occurrences consist of transplanted plants from other occurrences that were subsequently
partially or totally eliminated (CNDDB 2004). There are, therefore, 34 verifiable native reported
occurrences of this species. Twenty of these (59 percent) have been extirpated since the 1930’s,
nearly all by commercial development and activities associated with highway construction (U.S.
Fish and Wildlife Service 1999d). One occurrence, with a single stem in 1996, is considered
non-viable due to the small size of the occurrence and the high level of disturbance of the site
(CNDDB 2004). Subtracting this non-viable occurrence, there are currently 15 extant native
occurrences of this species. Twelve occurrences are in San Diego County, and three are in
western Riverside County (City of Lake Elsinore 2000).
Threats
The primary threat to San Diego ambrosia is habitat loss due to urbanization, habitat
fragmentation, isolation, and associated impacts from non-native species competition. Nearly all
U.S. populations occur in sites that are disturbed and frequently affected by secondary impacts
(e.g., trampling, non-native plant competition) due to proximity of development and
infrastructure (e.g., roads and utilities).
Environmental baseline:
Within the MHCP, San Diego ambrosia has been found in Oceanside and Escondido. Both the
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City of Oceanside and Escondido have two occurrences. However, the only population known to
persist is near Mission Boulevard in east Oceanside on a property referred to as Jeffries Ranch.
This popilation 1s classified as a major population area and a critical location in MHCP. Habitat
for San Diego ambrosia includes coastal sage scrub, grassland, or disturbed habitat. However, it
is typically associated with upper terraces of rivers and drainages.
There are no populations of San Diego ambrosia in the Carlsbad subarea (CNDDB 2004). It is
possible that there are undiscovered populations within suitable habitat in the Carlsbad subarea.
Effects of Action:
Direct Efects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1.
2.
3.
4.
5.
6.
- The major population and critical location of San Diego ambrosia in Oceanside must be
conserved at a level consistent with the critical location policy and managed as part of the
preserve system.
Fire management plans must be implemented for all conserved populations to protect
them from frequent or high-intensity fires and fire suppression activities.
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist must survey for this species in all potential habitat
areas.
The MHCP narrow endemic policy must be applied to any population of this species,
including those already known and any found in the future.
Declining populations must be enhanced and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restQration may include site-specific habitat improvement
actions. Unless analyses determine that there is no significant genetic variation between
populations, introduced plant materials must be from the parental population or a
population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
The MHCP Subregional Plan will conserve at least 95 percent of the one major population
critical location in Oceanside. The other occurrence in Oceanside is in the FPA and will be
conserved at 95 percent. The two occurrences in Escondido are outside of the FPA and will be
conserved at least 80 percent due to the narrow endemic policy.
The City’s Subarea Plan will have no drect effects to San Diego ambrosia because it is not
known to occur in the Carlsbad subarea. Undiscovered populations of the San Diego ambrosia
could exist in the marsh habitat or the grassland habitat. The plan will preserve 100 percent of
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marsh habitat, but only 38 percent of grassland habitat. If San Diego ambrosia is found in the
subarea it will be preserved per the narrow endemic standards. In addition, the City of Carlsbad
would no; receive coverage for this species until the City of Oceanside has a valid lO(a)(l)(B)
permit for their Subarea Plan from the Service with this species covered or the major and critical
population in the City of Oceanside near Mission Boulevard is preserved and managed in
perpetuity. Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 2 requires the City to document in writing that the necessary
conditions of coverage will be met with written concurrence from the Wildlife Agencies.
-
Indirect Effects
San Diego ambrosia may be wind or insect pollinated, but due to low seed production, it is
generally thought to primarily reproduce asexually by rhizomes. By using asexual reproduction,
populations may be naturally low in genetic diversity. Still it is important that pollen and seeds
can move between populations through a network of connected habitat to allow for genetic
interchange. The implementation of this plan will fragment habitat and prevent animals, that
may have acted as seed dispersal vectors, from moving between the Escondido Oceanside
populations. However, this species will be managed and monitored per the MHCP standards in
Volume 3 to identify if such issues are affecting San Diego ambrosia in the MHCP planning area.
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact San Diego ambrosia in
the Cities of Oceanside and Escondido by habitat loss from development. However, half of the
occurrences will be conserved at 95 percent and the other half will be conserved at least 80
percent. In addition, the one major population and critical location will be conserved at 95
percent. No direct impacts to San Diego ambrosia will occur from the Carlsbad Subarea Plan
because the species is not known to occur in Carlsbad and coverage for this species to the City of
Carlsbad does not begin until the City of Oceanside receives a lO(a)(l)(B) permit with this
species covered. In addition, all new occurrences will be protected by the narrow endemics
policy which assures that no more than 80 percent of any population will be impacted. All
remaining populations of San Diego ambrosia will be monitored and managed consistent with
the MHCP Management and Monitoring Plan (Volume 3), as a result, the plan will detect and
minimize any negative impacts that are affecting San Diego ambrosia. This species will also
benefit from the habitat that the MHCP Subregional Plan will preserve in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan
which will further reduce the indirect effects and benefit the species. After reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan and the City’s Subarea Plan are not likely to jeopardize the continued existence
or recovery of this species.
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Ceanothus verrucosus (Wart-stemmed ceanothus)
Status of the Species
Listing Status
Wartlstemmed Ceanothus is not a state or federally listed species. The California Native Plant
Society has placed this species on list 2 with a R-E-D (Rarity-Endangerment-Distribution) code
of 2-2-1, and a California Natural Diversity Data Bank ranking of G3S2.2.
Species Description
Ceanothus verrucusus is a member of the Rhamnaceae (buckthorn) family. It is also known as
white coast ceanothus. C. verrucosus is an evergreen shrub (<3 meters) with gray to brown
angled twigs with black “warty” bumps. Leaves are arranged alternately. The inflorescence is a
raceme with white flowers and a dark ovary, which can produce a capsule (fruit).
Distribution
Wart-stemmed ceanothus is limited in distribution to western San Diego County and Baja
California, Mexico (Skinner and Pavlik 1994). In San Diego County, it is found on the
immediate coast from Carlsbad south to the U.S.-Mexican border. It also occurs inland towards
San Marcos and Lake Hodges. Within the United States, large populations occur in Carlsbad,
Encinitas, Torrey Pines State Reserve, Carmel Mountain-Carmel Valley, San Marcos, Escondido,
and Point Loma. Smaller populations are known from Kearny Mesa-Clairemont Mesa-Miramar,
Soledad, and Spooner’s Mesa.
.
Habitat Afinity
Wart-stemmed ceanothus occurs in coastal chaparral intermixed with chamise (Adenustoma
fasciculaturn) and mission manzanita (Xylocuccus bicolor). Typically, wart-stemmed ceanothus
is a dominant shrub within the vegetation community where it occurs. It may be particularly
vigorous on north-facing slopes, but can accommodate more xeric aspects. Soil-types used by
this species include Exchequer rocky silt loams, terrace escarpments, and Gaviota fine sand
loams (Reiser 1996).
Life History
It is a highly fire-adapted species whose fire response is seed germination from a persistent seed
bank after exposure to intense heat (e.g., an obligate seeder after fire) (Keeley 1991). Many
species that germinate in profusion immediately after fire may lie as dormant seeds in the soil for
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50-100 years until after a fire, indicative of the great longevity for these species (Keeley 1991).
Seed longevity of the persistent seed bank of Ceanothus spp. is known to exceed 20 years (Quick
and Quick 1961). Dispersal of propagules is during spring and summer which facilitates the
avoidance of flowering and fruiting during the summer and fall drought. The seeds of this
species have less mass than those of species with non-refractory seeds and this possibly reflects
the environmental favorableness of the postfire environment for seedling establishment. In the
absence of fire, or other disturbance, opportunities for population expansion are largely lacking
(Keeley 1991). This species is presumably insect-pollinated (e.g., bees or beeflies, Wyatt 1983;
Conrad 1987). Flowering occurs between January and April.
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Population Trend
Several viry vigorous populations of wart-stemmed ceanothus are extant; however, it is declining
locally on the periphery of the coastal cities in San Diego County (Reiser 1996). Within the
United States, large populations occur in Carlsbad, Encinitas, Torrey Pines State Reserve,
Carmel Mountain-Cannel Valley, San Marcos, Escondido, and Point Loma. Smaller populations
are known from Kearny Mesa-Clairemont Mesa-Miramar, Soledad, and Spooner’s Mesa (Ogden
Environmental et al. 2000).
Threats
Threats to this species include development and associated edge effects (including fuel
modification, fuel suppression, and invasion of nonnative plants).
Environmental Baseline
In the MHCP this species occurs in Carlsbad, Encinitas, San Marcos, and Escondido. There are
seven major populations of wart-stemmed ceanothus throughout the MHCP planning area. The
populations within the MHCP represent the northern extent of the range for this species. The
major populations in Encinitas occurs on the slopes at Green Valley and Lux Canyon. The major
population in San Marcos occurs at Mount Whitney - Double Peak. The major populations in
Escondido occurs at Del Dios and Lake Hodges-San Dieguito River Valley. No critical
populations have been identified in the MHCP planning area. The MHCP planning area contains
9,292 acres of wart-stemmed ceanothus habitat (southern maritime chaparral and southern mixed
chaparral).
Within the Carlsbad subarea there are three major populations; in addition, there is one other
population near the intersection of Aviara Parkway and Palomar Airport Road. The three major
populations are located on the Kelly Ranch property, in central Carlsbad (along Palomar Airport
Road), and on the western slope of Green Valley. Each of the major populations contains several
point locations. This species has been impacted previously north of Agua Hediona Lagoon
(CNDDB data), in the area east of Interstate 5 between Poinsettia Lane and Palomar Airport
Road, on the La Costa Villages (The Greens) property, and in the area southeast of the
intersection of La Costa Ave and El Camino Real (CNDDB data). These projects were
permitted prior to this plan.
Effects of Action
Direct Effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
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1.
2.
The major population in the Mount Whitney-Double Peak area of San Marcos must be
conserved at a minimum of 70 percent of the existing population.
Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent fire and fire suppression activities. Develop fire management guidelines within
conserved areas that incorporate controlled bums (or other fuel reduction methods in
urban areas), while limiting fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
3. .
The majority (75 percent) of species location points are within the FPA throughout the MHCP
planning area. However, any occurrences outside of the PA will receive no protection since
there are no critical populations of this species and the species is not a narrow endemic or
wetland obligate. The City of Encinitas is expected to conserve 28 of 37 (76 percent) location
points and 74 percent of the major populations. The City of Escondido is expected to conserve
41 of 47 (87 percent) location points and 83 percent of the major populations. The City of San
Marcos is expected to conserve 20 of 46 (44 percent) location points and 70 percent of a the
major population at Mount Whitney - Double Peak. The City of Solana Beach is expected to
conserve 4 of 6 location points. Overall, the MHCP will preserve 6,554 acres (71 percent) of
wart-stemmed ceanothus habitat (southern maritime chaparral and southern mixed chaparral)
throughout the MHCP planning area.
In the Carlsbad Subarea Plan, a portion of each of the two northern populations (Kelly Ranch and
central Carlsbad) will be impacted by the plan. We do not have data that give information on the
areal extent of the populations or number of individuals in each population. Instead, we have
point locations where the plants have been reported. For the wart-stemmed ceanothus there are a
total of 37 point locations within the subarea; of these, seven point locations fall outside of the
preserve boundary and it is assumed that they will be impacted. In the central Carlsbad
population five of the point locations that will be impacted are associated with projects that will
occur along Poinsettia Lane and one point location on the north side of Batiquitos Lagoon will be
impacted. There is a single point location that will be impacted on the Kelly Ranch property.
However, the City of Carlsbad would not receive coverage for this species until the City of San
Marcos has a valid 10(a)( 1)(B) permit for their Subarea Plan from the Service with this species
covered. In addtion, the City of Carlsbad will not receive coverage for this species until they
have the legal access and funds available to manage and monitor this species as described in the
MHCP Volume 3 and the OSMP. Thus, development that would adversely affect this species
could not be permitted under Carlsbad’s HMP until such coverage is received by the City. The
process for initiating coverage for species in Table 2 requires the City to document in writing that
the necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
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Indirect Effects
The preseive design will make establishing a natural fire cycle difficult. This may effect the
ability of the wart-stemmed ceanothus to germinate and reproduce (MHCP Vol. 2, p. 4-54). The
long narrow bands of preserved habitat that this plant grows in are adjacent to developed areas,
therefore it would be difficult to conduct controlled bums. However, a fire management strategy
is a condition of coverage for this species. These indirect impacts would be avoided and
minimized by monitoring and management of this species according to MHCP standards.
However, the City would not be able to initially fund or gain access for management and
monitoring for the critical locations and most of the other occurrences in the City until a regional
funding source, or some other additional funds, are available. Because of this, coverage for this
species is not being proposed until the City of Carlsbad can document they have access and the
funds available to manage and monitor this species as described in the MHCP Volume 3 and the
OSMP.
Conclusion
We have concluded that the MHCP Subregional Plan and City’s Subarea Plan will directly
impact wart-stemmed ceanothus throughout the MHCP planning area by habitat loss from
development. However, no critical populations are identified within the MHCP and overall 75
percent of all known location points and 78 percent of all major populations will be conserved.
71 percent of wart-stemmed ceanothus habitat will be conserved. All remaining populations of
wart-stemmed ceanothus will be monitored and managed consistent with the MHCP
Management and Monitoring Plan (Volume 3) and coverage for this species to the City does not
begin until the City of San Marcos receives a lO(a)( 1)(B) permit with this species covered and
the City of Carlsbad can provide documentation to the Service and Department that adequate
access and funding is available. Thus, the plan will detect and minimize any negative impacts
that are affecting wart-stemmed ceanothus. The avoidance, minimization, and/or mitigation
measures included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any
impacts that may occur to this species. This species will also benefit from the habitat that the
MHCP Subregional Plan will preserve in perpetuity. This Preserve will be adaptively managed,
per the measures included in the MHCP Subregional Plan and the City’s Subarea Plan which will
further reduce the indirect effects and benefit the species. After reviewing the current status of
this species, the environmental baseline for the action area, the effects of the proposed action,
and the cumulative effects, it is the Service’s biological opinion that the MHCP Subregional Plan
and the City’s Subarea Plan are not likely to jeopardize the continued existence or recovery of
this species.
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Dudleya viscida (Sticky dudleya)
Status of the Species
Listing Status
Sticky dudleya is not a state or federal listed species. This species is on the California Native
Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 2-2-3, and a
California Natural Diversity Data Bank ranking of G2S2.2.
Species Description
DudZeya viscida, a member of the Crassulaceae (stonecrop) family, is one of about 45 species
within the genus Dudleya (Moran 1960). It is a member of the subgenus Stylophyllum, which
consists of about nine species of succulent perennials with narrow, often round in cross-section,
rosette leaves (Moran 1960, Bartel 1993). It is a small caudex-like sprouting perennial. Leaves
are evergreen, appearing oily and containing a resinous odor. The cyme inflorescence contains
white flowers.
Distribution
Sticky dudleya occurs in Orange, Riverside, and San Diego counties (Skinner and Pavlik 1994).
In San Diego County, the species occurs on Camp Pendleton (San Mateo Creek, Stuart Mesa,
bluffs at the mouth of the Santa Margarita River), Oceanside, Carlsbad, Escondido Creek, San
Dieguito River Valley, and Santa Fe Valley. The Oceanside and Carlsbad locations fall within
the MHCP. In Oceanside this species occurs at the mouth of the San Luis Rey River and in
Carlsbad along San Marcos Creek.
Habitat Afin ity
Sticky-leaved dudleya is found on mesic, mostly north-facing, and often steep, rocky canyon
slopes. Sticky-leaved dudleya is known to occur in chaparral, sage scrub, and coastal bluff scrub
(Skinner and Pavlik 1994). In San Diego County, it has been associated with exposed gabbroic
rock or in very shallow soils and cracks on vertical rock faces (Reiser 1996).
Life History
Sticky dudleya is an herbaceous perennial plant. It flowers between May and June. It is insect
pollinated (e.g., bees, bee flies, Wyatt 1983), and seeds are presumably self-dispersed. This
species may be susceptible to fires.
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Dudleya, as a group, has a fair amount of literature, particularly regarding systematics, genetics,
and distribution. Sticky-leaved dudleya is treated with other species. However, specific studies
of sticky-leaved dudleya regarding reproductive biology, pollination, and seed dispersal appear to
be lacking.
Population Trend
Sticky dudleya population are slowly declining (Reiser. 1996). There are fewer than twenty
occurrences in southeastern Orange, northern San Diego, and southwestern Riverside counties
(Munz 1974; Bartel 1993; CNDDB 2000).
Colonies south of the San Luis Rey River are not being adequately protected with dedicated open
biological space and appropriate buffers.
Threats
The primary threats to this species are road construction (e.g., road widening), development, and
associated edge effects. Sticky dudleya appears to be susceptible to fires and disturbances
associated with fire suppression.
Environmental Baseline
Three populations of sticky dudleya occur in the MHCP. Two of these populations occur in
Oceanside and one occurs in Carlsbad. The population at the mouth of the San Luis Rey River is
considered a major population and critical location. There are 16,980 acres of suitable sticky
dudleya habitat (coastal sage scrub and chaparral) in the MHCP planning area.
The one population that occurs in Carlsbad is considered a major population as well as a critical
location. The Carlsbad population is on the Villages of La Costa property. This project is
already permitted and the population of sticky dudleya is located on the preserved habitat
associated with this property.
Effects of Action
Direct Eflects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. The major population and critical location at the San Luis Rey River in Oceanside must
be conserved at a level consistent with the critical location policy and managed as part of
the preserve system.
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Fire management plans must be implemented for all conserved populations to protect
them from frequent and high-intensity fires and fire suppression activities. If determined
necessary to maintain the population, develop fire management guidelines within
conserved areas that limit fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
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2.
3.
The majority (74 percent) of location points are within the FPA throughout the MHCP planning
area. The current FPA design only protects 74 percent of the population at the San Luis Rey
River mouth, however, the above condition of coverage requires at least 95 percent of the
population be conserved. In addition, the MHCP Subregional Plan conserves 11,140 acres (66
percent) of sticky dudleya habitat.
In the Carlsbad Subarea Plan, the only known population of sticky dudleya is on a project that is
already permitted. Therefore, there are no direct effects anticipated from the implementation of
this plan. The plan conserves 65 percent of existing coastal sage scrub and 70 percent of
chaparral, yet only a small percentage of this habitat likely supports to proper microhabitat for
sticky dudleya. In addition, the City of Carlsbad would not receive coverage for this species until
the City of Oceanside has a valid lO(a)(l)(B) permit for their Subarea Plan from the Service with
this species covered. Thus, development that would adversely affect this species could not be
permitted under Carlsbad’s HMP until such coverage is received by the City. The process for
initiating coverage for species in Table 2 requires the City to document in writing that the
necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
It is possible that populations of sticky dudleya not yet discovered may be impacted, however,
the plan indicates that any newly discovered populations will have area specific management - directives, which will protect against negative impacts.
Indirect Effects
Sticky dudleya may be vulnerable to frequent fires or fire suppression techniques. It is important
that this be taken into account when the fire management plan is developed. Sticky dudleya will
benefit from this plan because the population being preserved is found near Box Canyon. This
area will provide habitat for pollinators as well as a habitat for future expansion by sticky
dudleya. These indirect impacts would be avoided and minimized by monitoring and
management of this species according to MHCP standards. The City will initially provide
management and monitoring for the major and critical population in the City. Any new
occurrences would be managed to MHCP standards as well.
Conclusion
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We have concluded that the MHCP Subregional Plan will directly impact sticky dudleya in the
City of Oceanside by habitat loss from development. However, some of this population is in the
FPA and’the entire population must meet the critical location policy. No direct impacts to sticky
dudleya will occur from the Carlsbad Subarea Plan because the only known location of this
species is within a preserved area and coverage for this species to the City of Carlsbad does not
begin until the City of Oceanside receives a lO(a)( 1)(B) permit with this species covered. All
remaining populations of sticky dudleya will be monitored and managed consistent with the
MHCP Management and Monitoring Plan (Volume 3), as a result, the plan will detect and
minimize any negative impacts that are affecting sticky dudleya. The avoidance, minimization,
and/or mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan will
reduce any impacts that may occur to this species. This species will also benefit from the habitat
that the MHCP Subregional Plan will preserve in perpetuity. This Preserve will be adaptively
managed, per the measures included in the MHCP Subregional Plan which will further reduce the
indirect effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
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Ferocactus viridescens (San Diego barrel cactus)
Status of the Species
Listing Status
San Diego barrel cactus is not a state or federal listed species. The California Native Plant
Society places this species on list 2 with a R-E-D (Rarity-Endangerment-Distribution) code of 1-
3-1, and a California Natural Diversity Data Bank ranking of G4S3.1.
Species Description
Ferocactus viridescens is a member of the Cactaceae (cactus) family. It is a squat, thick ribbed
and heavy spined barrel cactus that scarcely suggests the true barrel form of its near relative, the
desert barrel cactus (Ferocactus cylindraceus) (Lindsay 1963, Dawson 1966). This species
usually only has one stem and is less than one foot tall, but may sometimes form clumps and
grow taller (Lindsay 1963). The spines are ashy-red or yellowish, aging to horn color or gray,
and they have little transverse ridges or striations which mark their daily growth during
development (Lindsay 1963). The four main spines, which are sometimes nearly two inches
long, form a cross, backed by from eight to fifteen radiating secondary spines (Lindsay 1963).
Dawson (1966) noted that the spination on the San Diego barrel cactus has developed remarkably
complete protection against herbivores.
About twenty-eight kinds of barrel cactus are included in the genus Ferocactus, whose name
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means fierce or wild cactus (Lindsay 1963). Only two of these are found in San Diego County,
one along the coast (San Diego or coast barrel cactus; Ferocactus viridescens) and the other in
the desert’(Ca1ifornia or desert barrel cactus; Ferocactus cyEindraceus [= Ferocactus
acanthodes]) (Lindsay 1963, Hickman 1996).
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Distribution
This speiies is found from coastal San Diego County south to near Punta San Telmo in Baja
California, Mexico (Reiser 1996). In San Diego County, the species occurs along the coastal
slope from Oceanside (on a north-facing slope near the mouth of the San Luis Rey River) south
to the U.S.-Mexican border (Reiser 1996). The densest populations in San Diego County are
found on Otay Mesa (Reiser 1996). Reiser (1996) noted that this plant becomes increasingly rare
as one travels northward in the County. The species occurs in Encinitas, Carlsbad, and
Oceanside.
Reiser (1996) also noted that this species becomes increasingly rare as one travels inland.
Niehaus (1977) reported the elevation range of this species as 30-500 ft and noted that it occurs
inland as far as Poway, California. Others have reported inland occurrences of this species, but
they also note that this species seldom occurs more than 20 miles from the coast (Dawson 1966).
Habitat Afinity
Rocky hillside areas with sparse vegetation primarily within coastal sage scrub is preferred. This
species has also been documented in chaparral and grassland habitats.
Life History
The San Diego barrel cactus is insect-pollinated, has fleshy fruits, and the seeds are animal
dispersed (Ogden Environmental et al. 2000). During periods of drought, the folds in the barrel
cactus become deep and the stem is able to contract without crushing the cells (Raven et al.
1992). The folds also house the stomata which are protected from the wind and direct sun as the
stem contracts (Raven et al. 1992). Under extreme drought conditions many of the fine roots are
sloughed off, to prevent water loss to the soil (Raven et al. 1992). Because seedlings of barrel
cactus cannot tolerate extremely high temperatures and prolonged drought, they survive only in
certain years and in protected microhabitats (Raven et al. 1992).
Large succulents like the San Diego barrel cactus have a thick cortex that insulates the vascular
tissue (Thomas 1991). The cortex thickens with age, so older individuals may be more resistant
to fire than younger ones. However, because of the short stature of this species, it may be
particularly susceptible to fire. Humphrey (1974) notes that barrel cactus plants more than one
foot tall are rarely killed by fire because only their spines are combustible; plants less than that
height may suffer up to 75% mortality as a direct result of fire damage to the apical meristem, or
a combination of fire damage to the meristem and post-fire herbivory. The flowering period is
between May and June.
Population Trend
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In 1977, Niehaus noted that the development of coastal areas in San Diego County, “is rapidly
exterminating [San Diego barrel cactus] in the U.S.” Although the species was formerly
widespread within San Diego County, it now persists in numerous, fragmented populations
(Reiser 1996). The once vigorous colonies on Otay Mesa have been particularly impacted
(Reiser 1996). This species continues to persist at Torrey Pines State Reserve, Cabrillo National
Monument, Border Field State Park, and is now protected on portions of the San Diego National
Wildlife Refuge Complex.
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Threats
The primary threats to this species are urbanization, off-road vehicular traffic, horticultural
collecting, and edge effects.
Environmental Baseline
Within the MHCP San Diego barrel cactus occurs within Carlsbad, Encinitas, and Oceanside.
Two populations are considered.major populations and critical locations. They are located in
Oceanside and Encinitas. The population in Oceanside occurs along the north bank of the San
Luis Rey River in a relatively contiguous stand, however, there are no point locality data for this
population. The population in Encinitas occurs in Lux Canyon. There is only one population in
Carlsbad. It is located south of Palomar Airport Road, across the street from the Carlsbad Flower
Fields. San Diego barrel cactus occurs mostly in coastal sage scrub, but also in chaparral and
grassland. It is possible that this species occurs in other locations within the subarea, but not
likely, since the majority of this species’ distribution is to the south of Carlsbad.
Effects of Action
Direct effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. The major population and critical location at Lux Canyon in Encinitas must be conserved
at a level consistent with the critical location policy and managed as part of the preserve
system.
Fire management plans must be implemented for all conserved populations to protect
them from frequent or high-intensity fires and fire suppression activities. If determined
necessary to maintain the population, develop fire management guidelines within
conserved areas that limit fire frequency and emergency access.
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist must survey for this species in all potential habitat
areas. Newly found populations or individuals shall be avoided by the project to the
maximum extent feasible, and any individuals that cannot be avoided shall be salvaged
2.
3.
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and transplanted to a suitable preserve area.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
4.
The MHCP Subregional Plan will conserve 86 percent of the population in Lux Canyon due to
the FPA alone, however, more conservation will occur due to the above condition of coverage
that requires the critical location policy to be applied to this population. Excluding the City of
Oceanside, since there are no point data, a majority (88 percent) of species points occur in the
FPA. It is estimated that over 150 acres of potential habitat will be conserved in the FPA along
the north bank of the San Luis Rey River.
The population of San Diego barrel cactus located in Carlsbad is located in a proposed hardline
preserve which will not be directly impacted from the implementation of this plan. Any new
populations of San Diego barrel cactus found will be avoided, although the plant is not
considered a narrow endemic. To the extent that they can not be avoided, they will be
transplanted to suitable habitat, such as southern maritime chaparral or coastal sage scrub habitat.
However, the City of Carlsbad will not receive coverage for this species until the Cities of
Encinitas and Oceanside have valid lO(a)( 1)(B) permits for their Subarea Plans from the Service
with this species covered. Thus, development that would adversely affect this species could not
be permitted under Carlsbad’s HMP until such coverage is received by the City. The process for
initiating coverage for species in Table 2 requires the City to document in writing that the
necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
Indirect effects
This species can encounter indirect effects such as trampling and increased run-off from nearby
residential development. However, management of the preserve will minimize the indirect
effects to this species by minimizing edge effects, preventing disturbance and protecting against
frequent or catastrophic fires. These indirect impacts would be avoided and minimized by
monitoring and management of this species according to MHCP standards. The City will not be
able to initially provide funding and access for management and monitoring for the one
occurrence mapped in the City. However, since San Diego barrel cactus occurs in coastal sage
scrub, a majority of suitable habitat for this species will be managed initially and any new
occurrences would be managed to MHCP standards as well.
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact San Diego barrel
cactus by habitat loss from development. However, most of the species points are in the FPA
and the major population critical location in Encinitas at Lux Canyon must meet the critical
location policy. Thus, it is expected that at least 86 percent of this population will be protected.
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No direct impacts to San Diego barrel cactus will occur from the Carlsbad Subarea Plan because
the only @own location of this species is within a preserved area and coverage for this species to
the City of Carlsbad does not begin until the Cities of Encinitas and Oceanside receive a
lO(a)( 1)(B) permit with this species covered. All remaining populations of San Diego barrel
cactus will be monitored and managed consistent with the MHCP Management and Monitoring
Plan (Volume 3), as a result, the plan will detect and minimize any negative impacts that are
affecting San Diego barrel cactus. The avoidance, minimization, and/or mitigation measures
included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any impacts that
may occur to this species. This species will also benefit from the habitat that the MHCP
Subregional Plan will preserve in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan which will further reduce the indirect effects
and benefit the species. After reviewing the current status of this species, the environmental
baseline for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not
likely to jeopardize the continued existence or recovery of this species.
Quercus engelmannii Greene (Engelmann oak)
Status of the Species
Listing Status
Engelmann oak is neither a State nor a Federally listed species. This species is on the California
Native Plant Society’s list 4 with a R-E-D (Rarity-Endangerment-Distribution) code 1-2-2, and a
California Natural Diversity Data Bank ranking of G3S3.2.
Species Description
Engelmann oak, a member of Fagaceae (oak) family, was first described by Edward Lee Greene
(1889). It is a spreading evergreen tree, 5-18 meters tall, with a rounded crown, and with gray
bark containing narrow scaly ridges and shallow furrows (Roberts 1995). Leaves are 20-60 mm
long, leathery, flat, longer than broad, with a dull bluish-green upper surface and lower surface
hairy when young becoming glabrous (without hairs) in age. Acorn is 15-25 mm long, cylindric
to broadly elliptic, with a rounded tip, and with fruit maturing in one year.
Distribution
Engelmann oak occurs in the cismontane foothills of Los Angeles, Orange, Riverside, and San
Diego Counties; on Santa Catalina Island (one tree); and in very northern Baja California,
Mexico (Skinner and Pavlik 1994). Over 90% of the remaining stands of this species are
estimated to occur in San Diego County (Pavlik et al. 1991). Engelmann oaks occurs primarily
east of the MHCP study area in San Diego County, from the Santa Margarita Mountains on the
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Riverside County-San Diego County border southward towards Dulzura, and east to the desert
slope. Large populations are found in Pala, Lake Wohlford, Twin Flats, Boden Canyon,
Clevengei Canyon, Escondido, Valley Center, Ramona, and Featherstone Canyon. Large stands
occur in Escondido (Lake Wohlford and Daley Ranch) with smaller stands and/or individual
trees found in Carlsbad (vicinity of Agua Hedionda).
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Habitat Afinity
Englemann oaks grow between dry coastal plains and cold montane areas, within an upper
elevational limit of approximately 4,200 feet and a rainfall minimum of approximately fifteen
inches per year (Scott 1990). Southern oak woodlands with Engelmann oaks are generally
associated with grassland and sage scrub vegetation. Because of the Engelmann oak’s tendency
to grow near basalt caps with an understory of coastal sage scrub and/or grasses consisting of
both introduced genera, such as Brornus, Avena, Hordeum and Avena, and native genera, such as
Stipa, Engelmann oaks have been coined “mesa oaks.” Engelmann oaks also occur in riparian
woodlands, but are typically subdominant to coast live oak (Q. agrifolia) or other typical riparian
trees, such as willows (Salk spp.), cottonwoods (Populus spp.), and sycamores (Platanus
racernosa).
Life History
Engelmann oak is a deciduous tree. Seedlings are fire-tolerant, but mature trees are “fire-
sensitive” (Pavlik et al. 1991). Engelmann oak is wind-pollinated, and seeds (acorns) are both
self- and animal-dispersed. Engelmann oak trees have a life-span of 50 to 150 years, with a few
trees reaching ages of 350 years (Pavlik et al. 1995).
Population Trend
In Los Angeles County in the foothills near Pasadena and Pomona, Engelmann oak has been
nearly extirpated throughout most of its historic range by encroaching urban sprawl (Pavlik et al.
1991). In San Diego County, Engelmann oak populations are relatively abundant (San Diego
County holds 90% of the existing stands) and stable (Reiser 1994).
Threats
Poor reproduction is an apparent problem with this oak. This may be due to a variety of reasons,
foremost of which is cattle overgrazing. Other factors may include herbivory from small
mammals, birds, and insects on the acorns; as well as browsing from deer, and a need for specific
weather conditions to promote optimal seedling establishment. Competition with annual grasses
for soil moisture may also hamper the recruitment of the Engelmann oak (Stephenson and
Calcarone 1999). Accordingly, Engelmann oak stands are devoid of new trees that were
established in the last 75 to 125 years (Pavlik et al. 1995).
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Environmental Baseline
Within the MHCP planning area, small stands and/or individual trees are found in Carlsbad
(vicinity of Agua Hedionda), and larger stands occur in Escondido (Lake Wohlford and Daley
Ranch). Both populations in Escondido are major populations and critical locations. One
population also exists in San Marcos. There are 230 acres of englemann oak woodland in the
MHCP planning area.
There is a single population of Engelmann oak in the Carlsbad subarea. This population is made
up of three subpopulations. These subpopulations are situated in a west to east row between
Palomar Airport Road and Aviara Parkway, roughly following Poinsettia Lane.
Effects of Action
Direct Efiects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1.
2.
3.
All critical locations in Escondido must be substantially conserved in accordance with the
critical location policy and managed as part of the preserve system.
Fire management plans must be implemented for all conserved populations to protect
individual plants and habitat from frequent or high-intensity fires.
Declining populations must be enhanced and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
actions. Unless analyses determine that there is no significant genetic variation between
populations, introduced plant materials must be from the parental population or a
population in proximity.
Impacts to individual trees shall be avoided and minimized to the greatest extent
practicable during project design.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
4.
5.
A majority (83 percent) of species points and englemann oak woodland (82 percent) throughout
the MHCP planning area occur within the FPA. However, the plants outside of the FPA will
benefit from the above condition that impacts to individual trees shall be avoided and minimized
to the greatest extent practicable. The one San Marcos population is already 100 percent
conserved. A majority (85 percent) of the species points and the major populations critical
locations (84 percent) will be conserved in the City of Escondido. This includes 72 percent of
the Lake Wohlford population and 95 percent of the Daley Ranch population.
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Two of the subpopulations that make up the Carlsbad population are outside of the proposed
hardline preserve. These two western subpopulations will likely be directly impacted as a result
of this plh, however, according to the Carlsbad plan (Appendix C, p.C-28) only one of these
populations will be lost. In addition, the City has a no-net-loss of oak woodlands policy and the
MHCP Subregional Plan requires impacts to individual trees be avoided and minimized to the
greatest extent practicable. The eastern subpopulation, near El Camino Real, is located in
proposed hardline preserves and will be conserved. A portion of this population is on the
Villages of La Costa (The Greens) property which was already approved under a separate
10(a)( l)(B) permit. The rest of this subpopulation is on the Manzanita’s Partners property and
within the proposed preserve. However, the City of Carlsbad will not receive coverage for this
species until the City of Escondido has a valid lO(a)(l)(B) permit for their Subarea Plan from the
Service with this species covered. Thus, development that would adversely affect this species
could not be permitted under Carlsbad’s HMP until such coverage is received by the City. The
process for initiating coverage for species in Table 2 requires the City to document in writinglhat
the necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
Indirect Effects
Adult Engelmann oak trees will withstand the indirect effects, however their seedlings will be
venerable to edge effects, such a trampling and other disturbances. There will also likely be
problems with seed dispersal because of the restricted preserve design. These indirect impacts
would be avoided and minimized by monitoring and management of this species according to
MHCP standards. The City will initially provide management and monitoring for two of the
three occurrences in the City and there are no major and critical populations in the City. Any
new occurrences would be managed to MHCP standards as well.
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact Engelmann oak by
habitat loss from development. However, most of the species points are in the FFA and the
major population critical locations in Escondido will be conserved consistent with the critical
location policy. Thus, it is expected that at least 84 percent of this population will be protected.
Direct impacts to Engelmann oak will also occur from the Carlsbad Subarea Plan because at least
one population will be impacted even though there is a no-net-loss of woodland policy.
However, the City of Carlsbad will not receive coverage for this species until the City of
Escondido receives a 10(a)( 1)(B) permit with this species covered. All remaining populations of
Engelmann oak will be monitored and managed consistent with the MHCP Management and
Monitoring Plan (Volume 3), as a result, the plan will detect and minimize any negative impacts
that are affecting Engelmann oak. The avoidance, minimization, andor mitigation measures
included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any impacts that
may occur to this species. This species will also benefit from the habitat that the MHCP
270
27 1
Subregional Plan will preserve in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan which will further reduce the indirect effects
and benefit the species. After reviewing the current status of this species, the environmental
baseline for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not
likely to jeopardize the continued existence or recovery of this species.
27 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 272 -
SPECIES-BY-SPECIES EVALUATIONS
SPECIES OM TABLE 3: These are species which the City will not receive coverage for
immediately upon approval of their permit. The City’s coverage is contingent on access and
funding for management of conserved areas.
Arctostaphylos glandulosa ssp. crassifolia (Del Mar manzanita)
Status of the Species
Listing Status
Del Mar manzanita was Federally listed as an endangered species on October 7, 1996 (61 FR
52370). It is on the California Native Plant Society’s list 1B with a R-E-D (Rarity-
Endangerment-Distribution) code of 3-3-2, and a California Natural Diversity Data Bank ranking
of G5TlS 1.1.
Species Description
Arctostaphylos glandulosa ssp. crassifolia, a member of the Ericaceae (heath) family, was first
described by Jepson (1922) based on a specimen collected in Del Mar, San Diego County in
1906. Jepson (1925) later changed the nomenclature for the species to A. tomentosa var.
crassifolia. Wells (1968) changed the nomenclature for the species back to Arctostaphylos
glandulosa ssp. crassifolia.
The Del Mar manzanita is a medium sized (1-2.5 meters) woody shrub, also referred to as Costa
Baja Manzanita (Wells 1993). It has finely tomentose twigs extending from a reddish-gray and
generally smooth stem. The leaves are a bright green and the flowers occur in a white corolla
(Wells 1986).
Distribution
Del Mar manzanita is restricted to San Diego County and northwestern Baja California, Mexico
(Skinner and Pavlik 1994; US. Fish and Wildlife Servicel996b). In San Diego County, this
species is found on coastal bluffs from Oceanside (south of San Luis Rey River, not mapped)
south to La Jolla (Wells 1986), and inland to San Marcos, Lake Hodges, Los Peiiasquitos
Canyon, and possibly Miramar Reservoir. Large populations of this species occur in the City of
Carlsbad at Agua Hedionda, north of College Boulevard, east of the junction of El Camino Real
and Palomar Airport Road, east and west of El Camino Real between Palomar Airport Road and
Alga Road, and Green Valley-Olivenhain.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Habitat Afinit>,
- 273
Del Mar manzanita is commonly found in southern maritime chaparral with Adenostorna
fasciculatum (chamise) and Ceanothus verrucusus (wart-stemmed ceanothus). Preferred soils
include terrace escarpments and loamy alluvial land of the Huerhuero complex.
Life History
Del Mar manzanita is a burl-forming shrub that is fire-adapted (e.g., it sprouts from the burl,
which is the base of the stem or root-crown, after fire or cutting) (Wells 1986; Conrad 1987).
Despite its fire adaptations, it is adversely affected by frequent burning. Del Mar manzanita
flowers from December to April and is both insect and bird-pollinated (e.g., bees and
hummingbirds; Grant and Grant 1965). Because of the basal burl, and thus the potential for
repeated sprouting, individuals are typically long-lived and populations generally experience
relatively slow rates of individual turnover (Wells 1986). In addition, individuals are expected to
have relatively low seed set (Kelly and Parker 1991).
Population Trend
Del Mar manzanita formerly occurred in about 26 populations throughout its range. Currently,
22 populations are believed to be extant in the United States, and support an estimated 7,100 to
9,700 individuals (U.S. Fish and Wildlife Service 1996b). The majority of Del Mar manzanita
populations have been reduced and fragmented by urban and agricultural development, resulting
in a 50 percent decline in the overall number of stands and number of individuals since 1982.
For example, a population of nearly 500 individuals near San Dieguito Creek and the
surrounding maritime chaparral habitat was cleared and converted to agriculture (U.S. Fish and
Wildlife Service 1996b). Approximately 75 percent of extant individuals are concentrated in six
populations. Four of these populations occur in Carlsbad and Encinitas.
Threats
Threats to this species include agricultural conversion, development, habitat fragmentation, and
edge effects (including fuel modification, fire suppression, trampling, and invasive exotic plants).
Environmental Baseline
Approximately 75 percent of extant individuals are concentrated in six populations, four of
which occur in the MHCP planning area in the Cities of Carlsbad and Encinitas. The major
populations of Del Mar manzanita occur in Carlsbad at Agua Hedionda and Green Valley -
Olivenhain and in Encinitas at Lux Canyon and vicinity, Green Valley - Olivenhain, and Oak
Crest Park. All major populations are considered critical locations.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Within the Carlsbad subarea there are two populations, both of which are considered major
populatio,ns. Both of these populations are composed of several point locations of Del Mar
manzanita. The northern population of Del Mar manzanita is concentrated along El Camino Real
between Palomar Airport Road and Alga Road. This major population includes plants located
near Agua Hedionda, north of College Boulevard, east of the junction of El Camino Real and
Palomar Airport Road, and east and west of El Camino Real between Palomar Airport Road and
Alga Road. This is the most northern population for this species. The majority of the point
locations for this plant are concentrated on La Costa Greens and on properties to the west. Other
point locations in this population are located on the Kelly Ranch property and the City’s
proposed golf course property. The second population is on the border between Carlsbad and
Encinitas in the area referred to as Green Valley-Olivenhain. There are several point locations on
the east facing, chaparral covered slope of Green Valley. This population extends eastward,
along the boundary between Carlsbad and Encinitas. The habitat these two populations occur on
is discontinuous and constrained. However, it is possible that seed moving vectors such as birds
and mammals are able to transport seeds within each of these populations. It is less likely that
seed dispersal vectors are able to transport seeds between these two populations because of
residential and commercial development and the presence of busy roads.
274 -
Effects of Action
Direct eflecfs
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel
reduction methods in urban areas), while limiting fire frequency and emergency access.
The MHCP narrow endemic policy must be applied to any population of this species,
including those already known and any found in the future.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
The MHCP Subregional Plan and the City’s Subarea Plan will directly impact Del Mar
manzanita. However, the majority of the species points are within the FPA and will be
conserved at either 95 or 100 percent. Any points that are outside of the FPA, will be conserved
at a level of 80 percent or greater due to the narrow endemic policy. Additional conservation
may occur through the application of the critical location policy. Overall, 96 percent of the major
populations and critical locations of Del Mar manzanita will be conserved. Of the four major
populations and critical locations, the Oak Crest population in Encinitas will be entirely
conserved, the Agua Hedionda population will be 92 percent conserved, the Green Valley-
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Olivenhain population will be 98 percent conserved, and the Lux Canyon population in Encinitas
will be 95 percent conserved. In addition, 453 acres (72 percent) of suitable habitat (sandstone
substrates in southern maritime chaparral) for Del Mar manzanita will be conserved in the PA.
275 -
According to the Carlsbad Subarea plan, six percent of the known mapped point locations in the
Carlsbad subarea will be impacted by development. Of the 240 acres of the remaining suitable
habitat (southern maritime chaparral occurring on sandstone substrates) for this plant, 37 percent
will be lost to development as a result of this plan. Because this plant is a narrow endemic, the
plants that occur outside the preserved areas will be impacted at no greater than 20 percent.
These loses primarily will occur on the periphery of the northern population. The result will be
that Del Mar manzanita will not be able to expand its range in the City of Carlsbad. However,
the City of Carlsbad will not receive coverage for this species until documentation is provided
that assures the above conditions, including management and monitoring of this species in
perpetuity throughout the City, according to MHCP Volume 3 standards, can be met among the
signatories to the IA (City, Service, andor Department). Thus, development that would
adversely affect this species could not be permitted under Carlsbad’s HMP until such coverage is
received by the City. The process for initiating coverage for species in Table 3 is the same as for
species in Table 2 and requires the City to document in writing that the necessary conditions of
coverage will be met with written concurrence from the Wildlife Agencies.
Indirect eflects
The implementation of this plan will result in the removal of habitat that provided a protective
buffer for the Del Mar manzanita. The removal of this habitat will expose subpopulations of Del
Mar manzanita directly to a wide array of edge effects. This plant relies on fire for its
reproduction. It will be a challenge to mimic natural fire regimes in the habitat matrix that this
plan will create and in such close proximity to developments. This may significantly impede the
ability of the Del Mar Manzanita populations’ ability to avoid extinction. A fire management
plan is an important part of the monitoring and management plan requirements for this species.
The City of Carlsbad would only be able to ensure funding for management and monitoring for
only half of one of the two major and critical populations in the City once this plan is approved.
Thus, significant indirect effects would continue to occur to this species if management and
monitoring to MHCP standards was not conducted initially. Because of this, coverage for this
species is not being proposed until the City of Carlsbad can document they have access and the
funds available to manage and monitor this species as described in the MHCP Volume 3 and the
OSMP.
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact Del Mar manzanita in
the Cities of Carlsbad and Encinitas by habitat loss from development. However, overall 96
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
percent of all known location points, 96 percent of all major populations, 96 percent of all critical
populatiqns, and 72 percent of Del Mar manzanita habitat will be conserved. In addition, the
MHCP Subregional Plan assures that no more than 80 percent of any population will be impacted
outside of the FPA due to the narrow endemics policy. All remaining populations of Del Mar
manzanita will be monitored and managed consistent with the MHCP Management and
Monitoring Plan (Volume 3). Coverage for this species to the City does not begin until the City
of Carlsbad can provide documentation to the Service and Department that adequate access and
funding is available. The avoidance, minimization, and/or mitigation measures included in the
MHCP Subregional Plan and City’s Subarea Plan will reduce any impacts that may occur to this
species. This species will also benefit from the habitat that the MHCP Subregional Plan will
preserve in perpetuity. This Preserve will be adaptively managed, per the measures included in
the MHCP Subregional Plan and the City’s Subarea Plan which will further reduce the indirect
effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
276 -
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Buccharis vanessae (Encinitas baccharis)
- 277
Status of ihe Species
Listing Status
Encinitas baccharis was federally listed as threatened on October 7, 1996 (61 FR 52370). It was
listed as rare in California in July 1982 and later state-listed as endangered in January 1987.
Critical habitat has not been designated for this species, and a recovery plan has not been
adopted. A detailed account of the status, distribution, taxonomy, ecology, and reproductive
characteristics of Encinitas baccharis is presented in the final rule, which is hereby incorporated
by reference. This species is on the California Native Plant Society’s list 1B with a R-E-D
(Rarity-Endangerment-Distribution) code 2-3-3, and a California Natural Diversity Data Bank
ranlung of GISl.l
Species Description
Encinitas baccharis, a member of the Asteraceae (aster) family, was first described by
Beauchamp (1980) from a discovery by the author in October 1976 in southern maritime
chaparral on Eocene sandstones along the north side of Encinitas Boulevard in Encinitas.
Encinitas baccharis is a dioecious broom-like shrub, 0.5 to 1.3 m (1.6 to 4.3 ft) tall. This species
is distinguished from other members of its genus by its filiform leaves and delicate phyllaries
which are reflexed at maturity (Beauchamp 1980).
Distribution
Encinitas baccharis is a San Diego County endemic plant that is now limited to approximately 14
highly restricted populations throughout its range, including Encinitas, Carmel Mountain, Mt.
Israel-Del Dios, 4s Ranch, Mt. Woodson-Iron Mountain, Poway (Van Dam Peak), and Mira
Mesa (Beauchamp 1986; U.S. Fish and Wildlife Service 1996b). Most of these populations are
small, consisting of six or fewer plants and no population is known to contain more than 300
plants (U.S. Fish and Wildlife Service 1996b)
Small populations are found in Encinitas (Lux Canyon) and Escondido. Larger populations can
be found in the vicinity of Mt. Israel and in Carlsbad and Encinitas, on the slopes above Green
Valley.
Ha bitat Afin ity
Encinitas baccharis occurs in southern maritime chaparral and dense southern mixed chaparral.
This species is commonly associated with Adenostoma fasciculatum, Arctostaphylos glandulosa
ssp. crassifolia, Xylococcus bicolor and Yucca schidigera.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Life History
- 278
Encinitas’bacchAs is a dioecious’(i.e., male and female flowers are on separate plants), broom-
like shrub. It is likely a fire-adapted species that is enhanced by fire; however, the exact fire-
response mechanism is not known. It is presumably insect-pollinated (e.g., bees and/or
butterflies, Wyatt 1983), and seeds are presumably wind-dispersed. Flowering occurs between
August and November.
Population Trend
Encinitas baccharis is nearing local extirpation in Encinitas and is endangered by urban
development elsewhere in San Diego County. It is considered one of the rarest shrubs in
Southern California (Reiser 1996). Attempts to transplant this species locally have not been
particularly successful (Reiser 1996). The historic dlstribution of this species included 19 natural
populations scattered from Encinitas east through the Del Dios highlands and Lake Hodges area
to Mount Woodson and south to Poway and Camel Mountain in San Diego County. Fourteen of
these populations are still extant, with the total population estimated at 2,000 individuals. No
population is known to have over 300 individuals and five of these populations have fewer than
six individuals (U.S. Fish and Wildlife Service 1996b).
Threats
The most imminent threat to this species is the destruction or adverse alteration of chaparral
habitat by urban and agricultural development, recreational activities, trampling, and fuel
modification activities. Its restricted distribution, small population sizes, and disproportionate
sex ratios make Encinitas baccharis subject to extinction by stochastic events.
Environmental Baseline
Within the MHCP planning area, this species is known from Carlsbad, Encinitas, and Escondido.
There are two major populations of Encinitas baccharis in the MHCP. One major population is
in Carlsbad and Encinitas on the slopes of Green Valley. This population is considered a critical
location. In addition, a smaller population in Encinitas at Lux Canyon is also considered a
critical location. In Escondido, a major population is found in the vicinity of Mount Isreal.
There are 9,292 acres of potential Encinitas baccharis habitat (southern maritime chaparral and
southern mixed chaparral) in the MHCP planning area.
In addition to the two major populations, there are scattered occurrences in Encinitas and
Carlsbad. These occur in Encinitas, Carlsbad, and Escondido and are made up of 21 point
locations. The majority of these point locations are part of a major population that traverses the
border of Carlsbad and Encinitas along the western slope of Green Valley. This band spans
roughly 4 km from north to south. This species is not widespread despite the fact that it is wind
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 279
dispersed. The range of Encinitas baccharis and Del Mar manzanita overlap in Green Valley,
however, Encinitas baccharis’ range does not overlap with the range of Del Mar manzanita in
central Cblsbad. This indicates that there may be soil or microclimate differences that limit its
range. Other than the Green Valley population, there is one point location in Carlsbad to the
northwest of the intersection of Aviary Parkway and Black Rail Road.
-
Effects of the Action
Direct Efsects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel
reduction methods in urban areas), while limiting fire frequency and emergency access.
The MHCP narrow endemic policy must be applied to any population of this species,
including those already known and any found in the future.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
At least 98 percent of all known locations of this species will be conserved due to the MHCP
Subregional Plan because nearly all location points are within the FPA and any points outside of
the FPA will be conserved at least 80 percent due to the narrow endemic policy. In addition, due
to the critical location policy, a greater percentage will probably be preserved. Overall, 99
percent of the major populations and critical locations will be conserved. This includes 99
percent of the major population and critical location of Encinitas baccharis above Green Valley,
98 percent of the critical location at Lux Canyon, and 100 percent of the population at Mount
Isreal. Overall, 6,554 acres (71 percent) of potential Encinitas baccharis habitat in the MHCP
planning area will be conserved.
In the City of Carlsbad, all of the Encinitas baccharis are within the hardline preserve and will
not be directly impacted by this plan. Existing populations will likely be sustained by
management efforts, however, the preserve design does not allow room for this species to expand
its range. Because this plant is a narrow endemic, new populations of this plant found within the
preserve hardline and softline areas will be completely preserved, and populations found outside
this area will be conserved at a minimum of 80 percent. However, the City of Carlsbad will not
receive coverage for this species until documentation is provided that assures the above
conditions, including management and monitoring of this species in perpetuity throughout the
City, according to MHCP Volume 3 standards, can be met among the signatories to the IA (City,
Service, and/or Department). Thus, development that would adversely affect this species could
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
not be permitted under Carlsbad’s HMP until such coverage is received by the City. The process
for initiating coverage for species in Table 3 is the same as for species in Table 2 and requires the
City to dckument in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
280 -
Indirect Efsects
Indirect effects from development, recreation, and edge effects as described in the general
indirect effects section are expected to adversely affect this species. More specifically, increased
development between Green Valley and the single location at the intersection of Aviary Parkway
and Black Rail will likely make it difficult for pollen to travel between these two populations.
The movement of pollen could be crucial to the survival of this plant because reproduction
requires a male plant and a female plant. Active management and monitoring will help to avoid
this situation and minimize the other indirect effects identified. However, the City would not be
able to initially fund or gain access for management and monitoring for any of the major and
critical populations of this species in the City until a regional fundmg source, or some other
additional funds, are available. .Because of this, coverage for this species is not being proposed
until the City of Carlsbad can document they have access and the funds available to manage and
monitor this species as described in the MHCP Volume 3 and the OSMP.
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact Encinitas baccharis in
the Cities of Carlsbad and Encinitas by habitat loss from development. However, overall 99
percent of all known location points, major populations, and critical locations will be conserved
and 71 percent of Encinitas baccharis habitat will be conserved. In addition, the MHCP
Subregional Plan assures that no more than 80 percent of any population will be impacted outside
of the FPA due to the narrow endemics policy. All remaining populations of Encinitas baccharis
will be monitored and managed consistent with the MHCP Management and Monitoring Plan
(Volume 3). Coverage for this species to the City does not begin until the City of Carlsbad can
provide documentation to the Service and Department that adequate access and funding is
available. The avoidance, minimization, andor mitigation measures included in the MHCP
Subregional Plan and City’s Subarea Plan will reduce any impacts that may occur to this species.
This species will also benefit from the habitat that the MHCP Subregional Plan will preserve in
perpetuity. This Preserve will be adaptively managed, per the measures included in the MHCP
Subregional Plan and the City’s Subarea Plan which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline
for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not
likely to jeopardize the continued existence or recovery of this species.
280
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Brodiaea filifolia (Thread-leaved brodiaea)
- 28 1
Status ofthe Species
Thread-leaved brodiaea (Brodiaea filifolia)
Listing Status
Thread-leaved brodiaea was federally listed as threatened on October 13, 1998 (Federal Register
63: 54975) and was listed as endangered by the State of California in January 1982. Critical
habitat has not been proposed for this species, and a recovery plan has not been prepared. A
detailed account of the status, distribution, taxonomy, ecology, and reproductive characteristics
of thread-leaved brodiaea is presented in the final rule, which is hereby incorporated by
reference.
Species Description
Brodiaeafilifolia is a perennial herb in the Liliaceae (lily family). Each year, if there is adequate
rainfall, one or more narrow leaves emerge from the persistent, under-ground, fibrous-coated
corms. If the plants are mature and conditions adequate, each year the corms may produce a
solitary flower stalk. The flower stalks are 8 to 16 inches tall, extending above the leaves. The
flowers, arranged in an umbel, open between May and June. Each flower has a perianth
composed of six violet petal-like segments, 0.4 to 0.5 inches long, fused at the base and
spreading at their free ends. The three stamens alternate with tapered staminodia that are
appressed to the perianth (Keator 1993). The fruit is a capsule (Munz 1974, Keator 1993)
Brodiaeafilifolia is one of 13 species of Brodiaea, a genus largely restricted to California
(Keator 1993). Thread-leaved brodiaea belongs to the Filifoliae, a subgenus consisting of three
species (Niehaus 197 1). Its closest relative is,Brodiaea orcuttii which occurs sympatrically with
thread-leaved brodiaea in several locations. The two species hybridize (Niehaus 1971, Boyd et
al. 1992). Dudek and Associates (2000) state that this species also hybridizes with Brodiaea
terrestris var. kemensis (dwarf brodiaea) at the Santa Rosa Plateau and with Brodiaea jolonensis
(Jolon brodiaea). Brodiaea filifolia can be distinguished from these other taxa that occur within
its range by its narrow, pointed staminodia, rotate perianth (i.e, saucer-shaped flower), and a thin
perianth tube, which is split by developing fruit (Niehaus 1971, Munz 1974).
Distribution
Brodiaea filifolia is endemic to southwestern cismontane California, ranging from the foothills of
the San Gabriel Mountains at Glendora (Los Angeles County), east to Arrowhead Hot Springs in
the western foothills of the San Bernardino Mountains (San Bernardino County), and south
through eastern Orange and western Riverside Counties to Carlsbad and just south of Lake
28 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Hodges in northwestern San Diego County, California (Munz 1974, Keator 1993). This species
occurs frqm near sea level to 600 meters.
Habitat Afinities
282 -
Thread-leaved brodiaea typically occurs on gentle hillsides, valleys, and floodplains in semi-
alkaline mudflats, vernal pools, mesic southern needlegrass grassland, mixed native-nonnative
grassland and alkali grassland plant communities in association with clay, loamy sand, or
alkaline silty-clay soils (U.S. Fish and Wildlife Service 1998b). In Orange County and San
Diego County, the distribution of thread-leaved brodiaea is highly correlated with clay soils.
Occurrences of this species are frequently found with, or near, vernal pool complexes, such as at
the Santa Rosa Plateau and in the Upper Salt Creek drainage southwest of Hemet in Riverside
County (U.S. Fish and Wildlife Service 1998b).
Life History
The corm is the principal means by which plants of the genus Brodiaea perpetuate themselves
(Niehaus 197 1). By vegetative reproduction, corms from one year are replaced by new corms
each year. The corm of a mature plant often produces two to fifteen cormlets (Niehaus 1971).
Corms are dormant in the summer but begin growing after the first significant fall rains saturate
the soil (Smith 1997). Leaves are likely produced every year growing slowly throughout the
winter and dying back by the time of flowering (Smith 1997). Generally by early summer, next
seasons corms are mature. Young plants may produce only leaves for a few seasons before
corms have enough food stores to be capable of producing flower stalks. Flowering typically
occurs from May to June. Even mature specimens may not flower every year, depending upon
environmental conditions.
Sexual reproduction may occur in "pulses" when the dominant cover of European annuals is
reduced as a result of fire suppression (U.S. Fish and Wildlife Service 1998b). If conditions are
adequate some of the mature corms produce flower stalks. The flowering period lasts for two to
three weeks, and development of the capsules and seeds takes four to eight weeks. All species of
Brodiaea are self-incompatible, requiring cross-pollination to set seed (Niehaus 197 1). Niehaus
(1971) found that a broad spectrum of insects visit Brodiaeu flowers but only tumbling flower
beetles (Mordellidue) and sweat bees (Helictidae) were found to transport pollen between
flowers. On the Santa Rosa Plateau, Gary Bell found that native bees were faithful to specific
Brodiuea species but the European honeybee was not (U.S. Fish and Wildlife Service 1998b).
Upon maturity, the three-lobed fruits split open, revealing many small (2 to 2.5 mm long) black
seeds, which are then dispersed as wind rattles the capsules (Munz 1974). The rate of deposition
and duration of seeds in the soil is unknown. However, it is likely that most of the seeds are
dispersed nearby, and as such, would be scattered among the standing plants at any given
occurrence. Conditions conducive to trigBering natural germination are also unknown.
Seedlings produce contractile roots (roots of specialized form designed to shrink vertically under
conditions of seasonal drying) for the first few years. These roots swell with moisture in the wet
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 283
season creating a space in the softened substrate. As the season progresses the succulent root
dnes and shrinks vertically, drawing the young cormlet down in the soil. This is repeated for a
few years’ until the cormlet reaches the soil level where seasonal moisture is insufficient to
support the contractile root.
Individuals require several years to mature and frequently only a fraction of the mature
individuals flower in a given year: a field study at the Santa Rosa Plateau Preserve revealed an
8: 1 ratio of non-flowering corms to flowering plants and it is estimated that the number of
flowering plants may vary up to tenfold from wet to dry years (Dudek and Associates 2000).
Another study found that only 20 plants bloomed where 8,000 corms were later located (Dudek
and Associates 2000). The size of a particular population of Brodiaea species, as well as other
corm and bulb forming species, is often measured by counting numbers of standing flower stalks.
However, because more plants flower in wet years than dry years, flowering plants likely
represent only a portion of the total population of plants present at any given site. In one
translocation effort, 6-7 flowering corms were dug up and about 19 or 20 more non-flowering
corms were found. In addition to the annual fluctuation in numbers of flowering plants,
seedlings and young plants likely only produce leaves for a few years before they are able to
produce flower stalks. These vegetative plants may go undetected in surveys.
Population Trend
-
Thread-leaved brodiaea is declining throughout much of its range and is still substantially
declining throughout its southern California range. It occupies an estimated 825 acres of suitable
habitat, forty percent of which is reported from a single area (i.e., around Miller Peak in the Santa
Ana Mountains of Riverside County). Forty-eight populations of thread-leaved brodiaea have
been reported. At least nine of these populations have been extirpated, primarily in San Diego
County. Thirty-nine populations are presumed extant. Fifteen of these remaining populations
are clustered in the expanding cities of Vista, San Marcos, and Carlsbad in San Diego County (9
populations) and on the Santa Rosa Plateau in Riverside County (6 populations) (U.S. Fish and
Wildlife Service 1998b). Fewer than 500 individuals have been observed within half of the
populations. Populations exceeding 5,000 flowering stalks have been reported in only six
populations (U.S. Fish and Wildlife Service 1998b).
Threats
This species and its habitat are threatened by habitat destruction and fragmentation from urban
and agricultural development, pipeline construction, alteration of hydrology and floodplain
dynamics, clay mining, excessive flooding, channelization, off-road vehicle activity, trampling
by cattle and sheep, weed abatement, fire suppression practices (including disking and plowing),
and competition from alien plant species (CNPS 2001, U.S. Fish and Wildlife Service 1998b).
Environmental Baseline
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Thread-leaved brodiaea is known from Los Angeles, Orange, Riverside, San Bernardino, and San
Diego counties (Skinner and Pavlik 1994). Of 46 reported populations of this species, 37 are
presume2 extant. Nearly 25 percent of the extant populations occur within the MHCP in the
cities of San Marcos, Oceanside, and Carlsbad. The Service (1998b) has estimated that over the
last 15 years nearly 150 acres of occupied habitat containing 80,000 plants have been eliminated
in San Marcos and Vista.
284 -
Six major population areas for the Thread-leaved brodiaea occur in the MHCP. All of these
major population areas contain critical locations for the thread-leaved brodiaea. A major
populatiodcritical location area occurs in the City of Oceanside and another occurs in the City of
San Marcos. However, a large number of individuals in the City of San Marcos are within a
major amendment area. Four of the major populatiodcritical location areas occur in the City of
Carlsbad. In addition to the six major populatiodcritical locations, there are nine other locations
where this plant is found in the MHCP planning area (three in Oceanside and six in Carlsbad).
One of the populations in Oceanside was recently discovered to be impacted. Apparently, a
significant number of individuals on the west side of El Camino Real north of Mesa Drive were
dug up and removed from the site in April 2004. The perpetrator and cause of this action remain
unknown.
The largest population of this species, in terms of known number of plants expressed in a given
year, is in the City of San Marcos where an estimated 342,000 plants occur on an isolated, 40-
acre parcel. Most populations support fewer than 2,000 individuals.
The Service has formally consulted with the Corps on impacts to thread-leaved brodiaea
associated with development projects in the Cities of San Marcos and Oceanside. The Santalina
Ranch development project in San Marcos will directly impact approximately 14 acres of habitat
occupied by 461 of the 1,961 individuals of brodiaea filifolia on-site. The Taylor property and
the adjacent Darwin Glen property in Oceanside have both been approved for housing
developments. The Darwin Glen had no direct impacts to brodiaea filifolia and the Taylor
property will directly impact approximately 7 1 individual thread-leaved brodiaea are expected to
be directly impacted by the proposed project out of approximately 1,268 on the Taylor property
and approximately 3000 on the Darwin Glen property. The impacted plants will be translocated
elsewhere on the Taylor Estates property, outside the project footprint. The project impacts have
not yet occurred, so there is no information on the success of the translocation effort.
The Service has also formally consulted with the Federal Highway Administration on the
proposed interchange for State Route 78 (SR78) and Las Posas Road in San Marcos. This
population of brodiaea filifolia lies within the State right-of-way along SR78 and consists of two
sub-populations fragmented by SR78 and interspersed with Orcutt’s brodiaea. There are
approximately 378 thread-leaved brodiaea individuals, of which approximately 323 will be
directly impacted by the project. The impacted plants will be transplanted to a site acceptable to
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
the City and the Service. Transplantation efforts will be deemed acceptable when at least 80
percent (245 individuals) of the transplanted thread-leaved brodiaea individuals flower in 2 out
of the la& 3 of the 7 years in correlation with the reference populations. It is too soon to tell the
success of this translocation effort. However, it was expected that the translocation process may
result in an overall loss of up to 20 percent due to the difficulty in salvaging and transplanting
this species
285 -
The four major populatiodcritical location areas in Carlsbad identified in Volume 2 of the
MHCP occur on Calavera Heights, Carlsbad Highlands, Rancho Carillo and a one-acre preserve
in the northwest comer of El Camino Real and College Boulevard. The other populations occur
on Carlsbad Oaks North, Villages of La Costa (the Greens), on HOA lands in southern portions
of Carlsbad that have already been permitted for development, and the proposed Fox-Miller
hardline project. There are two populations reported in the CNDDB that were not included in the
MHCP document. One of these populations was located to the southeast of the intersection of La
Costa Ave. and Rancho Santa Fe Rd.; this population has been extirpated by development. The
other population is located south of Olivenhain Rd. along the lower hillsides to the north and
south of Encinitas Creek. It is possible that this population is still in existence, but no current
information is avaliable. The population on the Fox-Miller property has been documented as
having 19,100 individuals in 2003. This information was not available before the completion of
MHCP Volume 2, thus, it was not identified as a major population or critical location in that
document. However, the information available to-date clearly identifies that this population is a
major population since it is possibly the second largest population in MHCP. It should also be
considered a critical location since it is the largest population in the City of Carlsbad and is in
very close proximity to the one-acre brodiaea preserve. However, the City has already completed
CEQA and final maps for the site using the hardline development boundaries shown in the HMP.
This is problematic since the 2003 data indicates the hardline would directly impact 30 percent of
the population and significantly indirectly impact an additional 20 percent of the population. The
MHCP narrow endemic standard for critical populations requires the populations to be totally
avoided and any newly discovered major and critical populations to be maximally avoided, with
no more than 5 percent gross cumulative loss in the City.
Effects of Action
Direct Efsects
Brodiaea filifolia is a narrow endemic and as such will receive the protection of the narrow
endemic standard which does not allow for more than a 5 percent gross cumulative loss within
the FPA and a 20 percent gross cumulative loss outside of the FPA. In addition, the MHCP
requires the following conditions be met for a City to receive coverage for this species:
1. The major populations and critical locations of thread-leaved brodiaea in Oceanside,
Carslbad, and San Marcos must be conserved at a level consistent with the critical
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 286
location policy and managed as part of the preserve system, regardless of the timing or
method used to pennit take for individual projects or locations.
The MHCP narrow endemic policy must be applied to any populations of this species,
including those already known and any found in the future.
Watershed management plans must be implemented to avoid or minimize adverse
changes to vernal pool watersheds,
Fire management plans mut be implemented for all conserved populations to protect them
from frequent or high-intensity fires and fire suppression activities.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
(e.g. corms) to existing populations, while restoration may include site-specific habitat
improvement activities. Unless analyses determine that there is no significant genetic
variation between populations, introduced plant materials must be from the parental
population or a population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan Volume 3 shall be implemented.
-
2.
3.
4.
5.
6.
Due to the above standards and that 75 percent of the identified point locations are within the
PA, the expected loss of brodiaea filifolia is relatively low. In addition, even though only 27
percent of the species potential habitat (clay soils in grasslands and vernal pools) is conserved
throughout MHCP, surveys must be conducted for this plant in potential habitat at the
appropriate time of year and any new populations will be subject to the narrow endemic policy.
The only populations in areas that have not yet been permitted is on the Fox-Miller property.
The hardline exhibit in the Carlsbad subarea plan for this property would result in the direct loss
of 30 percent and significant indirect loss of an additional 20 percent of the 19,100 individuals
identified in 2003. However, in order to receive coverage for this species the City would need to
meet the conditions for coverage described above, which requires the narrow endemic policy be
followed. In addition, this population would have to meet the major population and critical
location policies as well. Thus, no more than 5 percent gross cumulative loss will occur of the
known brodiaea filifolia individuals on this property. Again, even though only 40 percent of the
species potential habitat (clay soils in grasslands and vernal pools) is conserved in the City,
surveys must be conducted for this plant in potential habitat at the appropriate time of year and
any new populations will be subject to the narrow endemic policy. Thus, development that
would adversely affect this species could not be permitted under Carlsbad’s HMP until such
coverage is received by the City. The process for initiating coverage for species in Table 3 is the
same as for species in Table 2 and requires the City to document in writing that the necessary
conditions of coverage will be met with written concurrence from the Wildlife Agencies.
Indirect Affects
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 287
Indirect effects to both the avoided and translocated thread-leaved brodiaea populations could
occur as a result of reduction in number of appropriate pollinator species, soil erosion, excessive
irrigation’runoff from adjacent residences, trampling by people and dogs, as well as fuel
reduction activities and associated spraying with herbicides. Habitat fragmentation increases
isolation and edge effects between disturbed and undisturbed habitat and can lead to a reduction
in pollination activities, particularly if the isolation caused by habitat fragmentation becomes
greater than the foraging range of pollinators, or if the pollinator population becomes small
enough (Kearns et al. 1998). This would result in diminished population viability because of
reduced seed production and inbreeding depression, increasing the risk of extinction
(Lennartsson 2002). Currently, there is insufficient data on thread-leaved brodiaea pollinators to
determine the degree of their plant specificity (Bell and Rey 1991), but the plant may rely on
relatively species-specific native bees (Federal Register 63: 54976). Thus, this species may be
more vulnerable to pollinator loss than a species that depends on multiple pollinators (Spira
2001). The best means of reversing the decline in a pollinator population is the conservation of
native bee habitat (Richards 1993), and while some native bee species may be able to tolerate
disturbed areas (Saure 1996), multiple types of habitat may be required to provide both foraging
and nesting requirements (Westrich 1996). It is unknown whether the pollinators necessary for
thread-leaved brodiaea will utilize areas in close proximity to the thread-leaved brodiaea
population.
-
The management for thread-leaved brodiaea will incorporate the following measures: 1)
Appropriate National Pollutant Discharge Elimination System (NPDES) erosion control
measures will be taken to reduce the potential for excessive soil erosion and irrigation runoff; 2)
Fencing will be placed between the proposed development and the on-site preserve to minimize
access by people and domestic animals; and 3) Fuel management activities will be conducted
outside the blooming period for the thread-leaved brodiaea and the removal of fuels will be
conducted in such a way as to minimize the ground disturbance. Although not all of the
locations with brodiaea filifolia in the City will be managed initially by the City, the only
substantial location with brodiaea on-site that will not be managed initially is on the Rancho
Carillo property with a major populatiodcritical location of 758 individuals. Two other locations
known to have brodiaea filifolia on-site in the past occur on HOA lands that will also not be
managed initially. However, neither of these locations are considered major or critical for the
species within MHCP and the other three major populations/critical locations will be managed
and monitored per the MHCP standards. The populations on the Fox-Miller property would need
to be managed per MHCP standards before the City would receive coverage for this species.
Conclusion
We have concluded that the MHCP Subregional Plan and the City’s subarea plan will directly
and indirectly impact thread-leaved brodiaea. However, no more than a 5 percent gross
cumulative loss is permitted by the MHCP standards for the populations on the Fox-Miller
property and any new populations would have to meet the narrow endemic policy. In addition,
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
the MHCP will provide monitoring and management of this species that will detect and minimize
negative impacts, that are affecting thread-leaved brodiaea. The City will provide management
and monitoring initially for all but one major population and critical location of this species and
would need to ensure the populations on the Fox-Miller property are managed to MHCP
standards before coverage would begin for the City. In addition, once funding is available, such
as through a regional funding source, the city will manage and monitor all locations.
Additionally, this species should benefit, at least from a pollinator standpoint, from the connected
preserve system that will be managed and monitored in the City and throughout the MHCP in
perpetuity. This Preserve will be adaptively managed, per the measures included in the MHCP
Subregional Plan, which will further reduce the indirect effects and benefit the species.
288 -
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Comarostaphylis diversifolia ssp. diversifolia (Summer holly)
-
Status of 'the SDecies
289
Listing Status
Summer holly is not a state or federally listed species. The California Native Plant Society has
placed this species on list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 2-2-2,
and a California Natural Diversity Data Bank ranking of G3T2S2.2.
Species Description
Comarostaphylis diversifolia ssp. diversifolia is a member of the Ericaceae (heath) family. It is a
large rigidly-branched and burled showy shrub (4 meters). Gray tomentose twigs give way to
often shredding bark. The leaves are alternate and evergreen with clearly rolled under margins.
The flowers are arranged in a raceme and produce a red juicy drupe (REF NEEDED).
Distribution
Summer holly occurs in Orange, Riverside, and San Diego counties, and in Baja California,
Mexico (Skinner and Pavlik 1994). In San Diego County, the species is found along the coast
from Carlsbad to the U.S.-Mexican border, and in inland locations from the San Marcos
Mountains south to Otay Mountain.
Populations of this species are found in Carlsbad (Agua Hedionda), Encinitas (vicinity of Green
Valley and Lux Canyon), San Marcos (Mt. Whitney-Double Peak), and Escondido (Merriam
Mountains and Del Dios).
Habitat Afinity
Summer holly is associated with southern mixed chaparral usually on north-facing slopes (Reiser
1996). This species can be found with well established Toyon and sparse Chamise. This species
occurs in ecosystems highly adapted to fire.
Life History
Summer holly is a fire-adapted shrub that stump-sprouts from the base of the stem or root-crown
after fire or cutting (Wells 1986; Conrad 1987). Because of its capacity for resprouting,
individuals are typically long-lived and populations typically experience relatively slow rates of
turnover of individuals (Wells 1986). It is presumably insect-pollinated and seeds are animal-
dispersed. This species flowers between April and June.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Population Trend
- 290
Summer holly is declining throughout its U.S. range (Reiser 1996). In northern San Diego
County major populations of this species are found in Carlsbad (Agua Hedionda), Encinitas
(vicinity of Green Valley, Lux Canyon), San Marcos (Mt. Whitney-Double Peak), and Escondido
(Del Dios) (Ogden Environmental et al. 2000). It is successfully cultivated for landscaping.
Threats
Threats to this species include development and associated edge effects (including fuel
modification, fuel suppression, and invasion of nonnative plants), as well as gravel mining.
Environmental Baseline
Within the MHCP planning area, summer holly is found in the cities of Carlsbad, Encinitas, San
Marcos and Escondido. There are six major populations of summer holly in the MHCP, none of
which are considered critical locations for this species. Two major populations are in Encinitas
in the vicinity of Green Valley and in Lux Canyon. One major population is in San Marcos at
Mt. Whitney-Double Peak and two major populations are in Escondido in the Merriam
Mountains and Del Dios. There is a total of 8,324 acres of summer holly habitat, chaparral, in
the MHCP planning area.
In 1999,968 acres of chaparral existed in Carlsbad. Currently not all of the chaparral is occupied
by summer holly. There are two major populations of summer holly in Carlsbad. In addition to
these two major populations, there are four other point locations for summer holly in the
Carlsbad subarea. The largest of the two major populations is located in central Carlsbad. This
population stretches from the Carlsbad Oaks North property in the north to Aviara Parkway in
the south. This population is made up of several point locations. About one third of the point
locations that make up this population are on county land and are not considered in the analysis
of this plan. The other major population in Carlsbad is in the Green Valley area and continues
into Encinitas. There are four other locations in Carlsbad where summer holly has been found.
The species occurs east of the Veteran’s Park property, north of Batiquitos Lagoon, on the Bressi
Ranch property, and on the Carlsbad Raceway property. Bressi Ranch, Carlsbad Raceway, and
Villages of La Costa have been previously permitted. On these permitted properties
approximately half of the point locations have been preserved.
Effects of Action
Direct effects
The &CP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
1.
29 1
Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent fires and fire suppression activities. Develop fire management guidelines within
conserved areas that incorporate controlled bums (or other fuel reduction methods in
urban areas), while limiting fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
-
2.
Direct impacts to summer holly will occur as a result of the MHCP Subregional Plan and the
City’s Subarea Plan. Only 60 percent of the summer holly points fall within the FPA, there are
no critical populations of this species in the MHCP planning area, and this species is not
considered a narrow endemic. Thus, all points outside of the FPA should be considered lost.
Direct impacts will occur in all the cities that have summer holly. Of the six major populations,
the Green Valley population in Encinitas and the Del Dios population in Escondido will be
entirely conserved within the FPA. Conservation of the remaining populations includes 88
percent of the Lux Canyon population (Encinitas), 64 percent of the Mt. Whitney-Double Peak
population in San Marcos, and none of the Merriam Mountains population in Escondido. In
addition, an estimated 5,806 acres (70 percent) of potentially suitable habitat will be conserved
throughout the MHCP planning area.
In the City of Carlsbad, approximately half of the point locations in the major population in
central Carlsbad will be lost to development, some of which is due to already permitted projects.
This is a substantial loss for this population. However, all of the point locations in the Green
Valley major population will be preserved within the Carlsbad Subarea Plan. The population
east of the Veteran’s Park property and the population north of Batiquitos Lagoon are in hardline
preserve areas and will be conserved 100 percent. However, the City of Carlsbad will not receive
coverage for this species until documentation is provided that assures the above conditions,
including management and monitoring of this species in perpetuity throughout the City,
according to MHCP Volume 3 standards, can be met among the signatories to the IA (City,
Service, and/or Department). Thus, development that would adversely affect this species could
not be permitted under Carlsbad’s HMP until such coverage is received by the City. The process
for initiating coverage for species in Table 3 is the same as for species in Table 2 and requires the
City to document in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
Indirect effects
Summer holly may be adversely effected by edge effects. Required management and monitoring
will minimize the effects associated with development in close proximity to populations of this
plant. These measures will include a fire management plan that considers the role fire should
play in maintaining this species. The fragmented nature of the preserve design will restrict the
transfer of genetic information, via pollinators and seed dispersal, between the populations of
29 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
summer holly. The MHCP management and monitoring program will help alleviate these
indirect effects. However, the City would not be able to initially fund or gain access for
management and monitoring for half of the one major population of this species in the City until
a regional funding source, or some other additional funds, are available. Because of this,
coverage for this species is not being proposed until the City of Carlsbad can document they have
access and the funds available to manage and monitor this species as described in the MHCP
Volume 3 and the OSMP.
292 -
Conclusion
We have concluded that the MHCP Subregional Plan will directly impact summer holly in all of
the cities it occurs (Carlsbad, Encinitas, San Marcos and Escondido) by habitat loss from
development. However, there are no critical locations of this species in MHCP and only one
major population will be completely lost. The MHCP Subregional Plan preserves 65 percent of
the major populations overall and 70 percent of summer holly habitat. In addition, the MHCP
Subregional Plan. All remaining populations of summer holly will be monitored and managed
consistent with the MHCP Management and Monitoring Plan (Volume 3). Coverage for this
species to the City does not begin until the City of Carlsbad can provide documentation to the
Service and Department that adequate access and funding is available. The avoidance,
minimization, and/or mitigation measures included in the MHCP Subregional Plan and City’s
Subarea Plan will reduce any impacts that may occur to this species. This species will also
benefit from the habitat that the MHCP Subregional Plan will preserve in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan
and the City’s Subarea Plan which will further reduce the indirect effects and benefit the species.
After reviewing the current status of this species, the environmental baseline for the action area,
the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to jeopardize
the continued existence or recovery of this species.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Corethrogyne filaginifolia var. linifolia (Del Mar mesa sand aster)
- 293
Status of ’the SDecies
Listing Status
Del Mar mesa sand aster was proposed as federally threatened on October 1, 1993 along with
five other southern maritime chaparral plant taxa (58 FR 51302). The Service subsequently
received additional information regarding the taxonomic status of Del Mar mesa sand-aster
indicating that this taxon was not distinct from the more widespread Lessingia filaginifolia var.
fiZaginifoZia (Lane 1992, Lane 1993). Based on this new information, the Service determined
that the taxon did not qualify for listing under the Act (61 FR 52402), but added the caveat that,
“the status and/or validity of such taxa may be reevaluated in the future on the basis of new
information” (U.S. Fish and Wildlife Service 1993~). Del Mar mesa sand aster is recognized as a
valid taxon by the California Native Plant Society (CNPS). The CNPS has placed this species on
list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 3-3-3. The Del Mar sand aster
has a CNDDB rank of G4TlS 1 ..I.
Species Description
Corethrogyne filaginifolia var. Zinifolia, is a member of the Asteraceae (sunflower) family. This
taxon was described by H.M. Hall (Hall 1907) based on a specimen collected by Kathrine
Barrndegee at Del Mar, San Diego County in 1906. Hall’s treatment was followed by Canby
(1927) in her treatment of the genus. Ferris (1958) elevated this to a specific rank as c.
Zinifolia (H.M. Hall) Ferris. Ferris followed this in her contribution to the Illustrated Flora of the
Pacific States (Abrams, L., and R.S. Ferris 1960). Floristic treatments (Munz & Keck 1959,
Munz 1974, and Beauchamp 1986) recognize this plant at the varietal rank Corethrogyne
filaginifolia var. linifolia. Lane (1993) merged the genus Corethrogyne with Lessingia and
transferred the Corethrogyne species into Lessingia, but did not recognize most of the
subspecific entities of Corethrogyne filaginifolia. The recent CNPS Inventory (CNPS 200 1)
recognized the Del Mar mesa sand aster as Corethrogynefilaginifolia var. linifolia. We will
follow this treatment of the plant’s status until such time as conclusive studies are available
indicating the subspecific status of Del Mar mesa sand aster.
The Del Mar mesa sand aster is an erect, divaricately branched perennial, 4.5 to 5 decimeters
(dm) (18-20 inches (in)) tall with violet ray flowers and yellow disk flowers. Hall (1907)
differentiated this subtaxon from other subtaxa by the narrow form of the leaf and the persistent
tomentum about the involucre, branches, and leaves. Del Mar mesa sand aster also lacks a
conspicuously glandular involucre.
Distribution
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Del Mar mesa sand aster is a San Diego County endemic plant that occurs along bluffs or brushy
slopes ne,= the coast from Carlsbad southward to Point Loma. The bulk of Occurrences for this
species are clustered around Del Mar. Major Populations of Del Mar mesa sand aster are found
in Carlsbad (Batiquitos, vicinity of Green Valley), Encinitas (Batiquitos, vicinity of Green
Valley, Lux Canyon and vicinity, San Elijo), and Solana Beach (San Elijo).
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Habitat Affinity
Del Mar mesa sand aster is found in sandstone substrates where it is generally associated with
coastal sage scrub or chaparral (including southern maritime chaparral). This species prefers
openings or sandy terraces over dense brush (U.S. Fish and Wildlife Service 1993~).
Life History
Del Mar mesa sand aster is insect pollinated (e.g., bees, butterflies, Wyatt 1983), and seeds
(achenes) are presumably wind and animal dispersed. This taxon appears to be tolerant of some
surface disturbance. Flowering.occurs between June and August.
Population Trend
Historically, this species was known from at least 17 populations. Thirteen of these populations
were extant in 1993 with six relatively large populations and eleven small and considerably
fragmented populations (Hogan 1990 in [ 19931). A small population just north of the University
of California at San Diego was largely eliminated in November 1992 by grading in conjunction
with the widening of John Hopkins Road. Jim Dice (Caltrans, pers. corn., 1992) estimated that
at least 20,000 individuals existed in 1992 (cited in U.S. Fish and Wildlife Service 1993~).
Construction projects have likely impacted populations of Del Mar mesa sand aster since 1992
(U.S. Fish and Wildlife Service 1993c), and Reiser (1996) notes that this species is declining
substantially. However, it is still locally common in the Del MarEncinitas region (Reiser 1996,
Ogden Environmental et al. 2000).
Threats
Del Mar mesa sand aster may be adversely affected by unnatural fire regimes (e.g., frequent fires,
high intensity fires resulting from fire suppression policies), particularly where they result in a
type conversion of native habitat and/or invasion of habitat by nonnative weedy species. A
considerable portion of the historic range of Del Mar mesa sand aster has been eliminated by
urban development within the cities of Carlsbad, Encinitas, and Del Mar, and elsewhere within
northern San Diego County. Remaining populations have been subject to fragmentation,
isolation and edge effects in these areas. This species is also threatened by trampling, non-native
plants, and off-road vehicle activity (U.S. Fish and Wildlife Service 1993~). Development and
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
associated edge effects continue to be the most significant threat to Del Mar mesa sand aster
(Ogden Environmental et al. 2000).
295 -
Environmental Baseline
A large portion of the Del Mar mesa sand aster’s range occurs in the MHCP. There are four
major populations in the MHCP as well as other scattered populations. Within the MHCP, Del
Mar mesa sand aster is found in Carlsbad, Encinitas, Oceanside, Solana Beach, and Vista. The
major populations in Encinitas are found at Batiquitos Lagoon, the vicinity of Green Valley, Lux
Canyon and vicinity, and San Elijo Lagoon. In Solana Beach Del Mar mesa sand aster is found
at San Elijo Lagoon. None of the populations in the MHCP are considered critical at this time.
Del Mar mesa sand aster is generally found on sandstone substrates in coastal sage scrub or
chaparral. An estimated 1,097 acres of this type of habitat occurs in the Carlsbad subarea. Only
a small percentage of this habitat is occupied by Del Mar mesa sand aster. There are likely more
specific requirements needed for this species to persist in an area. Further study is needed to
estimate how much habitat is actually available for this species and what percentage will be
impacted. There are 11 location points in the City of Carlsbad and two major populations. One
of the major populations is also partially in Encinitas on the western slope of Green Valley. In
addition to this population, there are three other populations in Carlsbad. One is in the
southeastern section of Carlsbad near Encinitas Creek, another is in central Carlsbad on either
side of El Camino Real, and the third is north of the Kelly Ranch property. The population north
of Kelly Ranch is the most northern population in the Carlsbad subarea; it is located in a
proposed standards area. However, part of this area appears to have been graded in the past. The
population in central Carlsbad on either side of El Camino Real is partially preserved. On the
east side of El Camino Real it is in the hardline preserve area of Villages of La Costa (The
Greens) which is already permitted, and on the west side of El Camino Real it is in a proposed
standards area. The population in Green Valley is in an existing hardline preserve. The
population in southeastern Carlsbad is located to the southwest of the intersection of Olivenhain
Road and Rancho Santa Fe Road near Encinitas Creek. This population is mapped outside of the
hardline preserve area.
Effects of the Action
Direct Eflects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. Fire management plans must be implemented for all conserved populations to promote
biological goals (e.g. regeneration) while protecting individual plants and habitat from
frequent fires and fire suppression activities. Fire management plans should include
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 296 -
emergency access plans for conserved areas to protect populations from fires and
disturbances associated with fire suppression.
The MHCP Narrow Endemic Policy must be applied to any populations of this species,
including those already known and any found in the future.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
4.
The expected loss of Del Mar mesa sand aster throughout the MHCP Subregional Plan is low
because a majority of the known location points are within the FPA and will be conserved at
levels of 95 percent or 100 percent. Points that fall outside of the PA will be conserved at a
minimum of 80 percent due to the narrow endemic policy. Additional conservation is expected
due to the critical location policy. Of the four major populations of this species that were
identified in the MHCP planning area, the Lux Canyon and San Elijo Lagoon populations in
Encinitas will be entirely conserved (100 percent) in the PA. An estimated 96 percent of the
Green Valley population will be conserved in Carlsbad and Encinitas and 80 percent of the
Batiquitos population will be conserved at 80 percent due to the narrow endemics policy. In
addition to conserved point localities, 1,953 acres (70 percent) of potentially suitable habitat
(sandstone substrates in coastal sage scrub or chaparral, including southern maritime chaparral)
will be conserved.
~ The Carlsbad Subarea Plan will impact one of the four populations of Del Mar mesa sand aster:
the population in the southeastern section of Carlsbad near Encinitas Creek. This plant is
considered a narrow endemic, therefore this population will be impacted at no greater than 20
percent. Any new populations found will be completely conserved (100 percent) if they occur
within the preserve, and conserved at a minimum of 80 percent if they are not in the preserve
area. However, the City of Carlsbad will not receive coverage for this species until
documentation is provided that assures the above conditions, including management and
monitoring of this species in perpetuity throughout the City, according to MHCP Volume 3
standards, can be met among the signatories to the IA (City, Service, and/or Department). Thus,
development that would adversely affect this species could not be permitted under Carlsbad’s
HMP until such coverage is received by the City. The process for initiating coverage for species
in Table 3 is the same as for species in Table 2 and requires the City to document in writing that
the necessary conditions of coverage will be met with written concurrence from the Wildlife
Agencies.
Indirect eflects
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
All of the populations, except for the population in Green Valley, are either on small patches of
native habitat or near the edge of the preserved area. These populations will be vulnerable to
edge effe’cts such as trampling and increased run-off and frequent or extremely hot fire. The
invasion of exotic plants into these native habitats is one of the major threats to this species.
Such indirect effects would be avoided and minimized by the management and monitoring of the
species in the preserve areas according to MHCP standards. However, the City would not be
able to initially fund or gain access for management and monitoring for any of the major and
critical populations of this species and half of the other populations in the City until a regional
funding source, or some other additional funds, are available. Because of this, coverage for this
species is not being proposed until the City of Carlsbad can document they have access and the
funds available to manage and monitor this species as described in the MHCP Volume 3 and the
OSMP.
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Conclusion
We have concluded that the MHCP Subregional Plan will directly impact Del Mar mesa sand
aster in the Cities of Carlsbad and Encinitas by habitat loss from development. However, overall
93 percent of all known location points will be conserved and 70 percent of Del Mar mesa sand
aster habitat will be conserved. In addition, the MHCP Subregional Plan assures that no more
than 80 percent of any population will be impacted outside of the FPA due to the narrow
endemics policy. All remaining populations of Del Mar mesa sand aster will be monitored and
managed consistent with the MHCP Management and Monitoring Plan (Volume 3). Coverage
for this species to the City does not begin until the City of Carlsbad can provide documentation
to the Service and Department that adequate access and funding is available. The avoidance,
minimization, and/or mitigation measures included in the MHCP Subregional Plan and City’s
Subarea Plan will reduce any impacts that may occur to this species. This species will also
benefit from the habitat that the MHCP Subregional Plan will preserve in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan
and the City’s Subarea Plan which will further reduce the indirect effects and benefit the species.
After reviewing the current status of this species, the environmental baseline for the action area,
the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan and the City’s Subarea Plan are not likely to jeopardize
the continued existence or recovery of this species.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Eryngium aristulatum var. parishii (San Diego button-celery)
Status of the SDecies
- 298
Listing Status
San Diego button-celery was federally listed as endangered on August 3, 1993 (58 FR 41391). It
has been listed as endangered in the State of California since July 1979. Critical habitat has not
been designated for this species. A vernal pool recovery plan which included San Diego button-
celery was published in September 1998 (U.S. Fish and Wildlife Service 1998b). This species is
on the California Native Plant Society list 1B with a R-E-D (Rarity-Endangerment-Distribution)
code of 2-3-2, and a California Natural Diversity Data Bank ranking of G5T2S2.1. The MHCP
considers this species to be narrow endemic.
Species Description
Eryngium aristulatum var. parishii is a perennial herb from a persistent tap root. The plant has a
spreading to erect habit, reaching a height of 41 centimeters (16 inches) or more. The stems and
toothed leaves are gray green with spinose lobes, giving it a prickly appearance. Inflorescence
forms on short peduncles (stalks) with few to many-flowered heads. Flowers are white and vary
in length from 1.7 to 2.8 millimeters (Munz 1974).
E. a. parishii, a member of the Apiaceae (carrot) family, was originally described as E. parishii
by Coulter and Rose (1900). Some references have confused E. parishii with E. jepsonii var.
parishii (Jepson 1923). Mathias and Constance (1941 separated E. aristulatum from E. jepsonii
due to morphological characteristics and treated this plant as E. aristulatum var. parishii. E. a.
parishii is separated from E. a. aristulatum by having styles in fruit that are about the same
length as the calyx (outer whorl of protective leaves around the flower) and is separated from E.
a. hooveri by having bractlets (modified leaves) without callused margins (Constance 1996).
Many of the populations identified as E. a. parishii on Camp Pendleton Marine Corps Base are a
recently described new species: E. pendletonensis (Marsden and Simpson 1999). San Diego
button celery is distinguished from E. pendletonensis by a combination of leaf and flower
characteristics.
Distribution
San Diego button-celery occurs in vernal pools from the Santa Rosa Plateau, Riverside County,
California, south to the mesas north of Ensenada, Mesa de Colonet, and San Quintin, Baja
California, Mexico ([K. Marsden, pers. comm., 19971 in U.S. Fish and Wildlife Service 1998b).
In San Diego County it is found in pools on Del Mar Mesa, Mira Mesa, Kearny Mesa, Marine
Corps Air Station, Miramar, Marine Corps Base, Camp Pendleton, and at sites within the cities
of Tierrasanta, San Marcos, Carlsbad, and Ramona; it was extirpated from a site in the city of La
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Jolla (Bauder 1986). San Diego button-celery is also found in the southern portion of San Diego
County on Otay Mesa, near the Lower Otay Reservoir and in Proctor Valley. It also was found
near the Tijuana’Airport, but is believed to be extirpated at this locale. There are no known
herbarium collections of San Diego button-celery from the San Diego Mesa (e.g., Normal
Heights, San Diego State University) (U.S. Fish and Wildlife Service 1998b). The California
Native Plant Society (2001) notes that this plant has been found at elevations from 20-620 meters
above mean-sea-level.
299 -
Habitat Aflnity
San Diego button-celery is associated with white clay bottom vernal pools devoid of hardpans
(U.S. Fish and Wildlife Service 1993b). However, this species is somewhat more tolerant of
peripheral vernal pool habitat than most obligate vernal pool species such as Pogogyne abramsii
(San Diego Mesa mint) with which it sometimes grows (Reiser 1994).
Life History
Most commonly a perennial herb with a persistent tap root, San Diego button-celery is
occasionally an annual under less favorable conditions. San Diego button-celery flowers from
April to June. It reproduces by out crossing and is presumably insect-pollinated (Ogden
Environmental et al. 2000). It is reliant on vernally wet conditions and has developed
mechanisms such as Aerenchyma tissue that promotes gas exchange underwater to cope with this
habitat.
Population Trend
In 1979, San Diego button-celery was known from 65 pool groups; by 1986, this plant remained
in 61 pool groups (U.S. Fish and Wildlife Service 1993b); and by 1998, San Diego button celery
continued to exist in 61 pool groups (U.S. Fish and Wildlife Service 1998b). Although several
sites receive some protection, Reiser (1996) stated that this subspecies is severely declining with
continued losses. Many existing pool groups are remnant colonies of once larger populations and
are subject to various forms of authorized and unauthorized disturbance (U.S. Fish and Wildlife
Service 1993b, Reiser 1996).
Threats
This species is threatened by urbanization and agricultural conversion throughout much of its
range, and by off-road vehicle use, livestock grazing, trampling and competition with non-native
species (U.S. Fish and Wildlife Service 1993b, 1998b).
Environmental Baseline
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
San Diego button-celery is rare within the MHCP, however it occurs more frequently than many
of the other vernal pool species included in this plan. There are two populations located in the
MHCP, 60th of which are considered major populations. One of these populations is located in
San Marcos and the other is in the City of Carlsbad at the Poinsettia Lane Commuter Station.
However, all of the populations in San Marcos are in the major amendment area. Thus, the
conditions of the MHCP for this species will not apply to these areas and adverse affects to these
areas will not be covered by the MHCP plan. However, the pools in San Marcos on the Bent
Avenue property will be conserved. A U.S. Army Corps of Engineers permit (Corps Permit No.
200001 113-TCD) was issued to South Coast Development on December 15,2000, which
required a the long-term preservation of 4.5 acres of vernal pool watershed on the Bent Avenue
property via a recorded conservation easement over the areas to be conserved. In 1993,12
populations of 774 individuals were observed on the Bent Avenue property. It is our
understanding that the conservation easement has not yet been recorded.
300 -
The pools at Poinsettia Lane have been degraded by agriculture and construction of the train
station, however, they continue to function as vernal pool habitat. San Diego button-celery
continues to persist in these pools. The Poinsettia Lane pools and their watersheds occur on both
North County Transit District (NCTD) land and private property associated with the Water’s End
housing development project. The Service formally consulted under section 7 of the Act (1-6-
94-F-9) with the U.S. Army Corps of Engineers on the adverse affects associated with the train
station on this species (U.S. Fish and Wildlife Service, 1994b). In response to this consultation,
NCTD agreed to grant a conservation easement over all the pools on their property to the
California Department of Fish and Game and provide a management plan with an endowment for
the management of the pools. These obligations remain outstanding, however, active progress is
being made. The Water’s End development has agreed to avoid impacts to the vernal pool
watersheds and will provide an easement over the pool watersheds on their property to the City
with California Department of Fish and Game and the US Fish and Wildlife Service as third
party beneficiary. In addition, they are providing $100,000 of funds to the City for an
endowment to manage and monitor the Poinsettia Lane pool watersheds. The California
Department of Fish and Game and the City of Carlsbad will ensure that these pools and their
watersheds are managed to MHCP standards.
There are two other vernal pool complexes in Carlsbad that may provide suitable habitat for San
Diego button-celery, but the species is currently unreported from these two areas. It is possible,
although unlikely, that there are small vernal pool complexes in Carlsbad that have thus far been
undetected which may provide habitat for San Diego button-celery.
Effects of the Action
Direct Eflects
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The MHCP Subregional plan requires the following conditions be met for a city to receive
coverage for this species:
1.
30 1 -
The major population and critical location of San Diego button-celery in San Marcos
must be conserved at a level consistent with the critical location policy and managed as
part of the preserve system. Depending on resolution of conservation for this species in
the San Marcos Major Amendment Area, permits for this species take could be revoked
in the future.
The MHCP Narrow Endemics Policy must be applied to all populations of this species,
including those already known and all found in the future.
All conserved populations must be adequately managed to control edge effects and avoid
adverse changes to vernal pools and their watersheds. Stabilize preserved populations by
removing impacts or potential impacts, and excluding adverse activities within preserve
areas and within the watersheds of vernal pools (e.g., trampling, vehicular or recreational
traffic, illegal dumping, invasive exotic plants, water pollution, alteration of hydrology,
and collecting). Regulate the use of toxic substances (e.g., herbicides, pesticides) and
control nonnative competitive species in the vicinity of vernal pools.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
4.
5.
Applying the above conditions throughout the MHCP planning area will result in a majority of
species points being conserved at a level of 100 percent, since most of the points are in the FPA
and the San Marcos species points need to be conserved consistent with the critical location
policy for narrow endemics. Any new species points identified would need to follow the narrow
endemic policy, which would require no more than 20 percent gross cumulative loss outside of
the FPA.
The City of Carlsbad will not receive coverage for this species until documentation is provided
that assures the above conditions, including management and monitoring of this species in
perpetuity throughout the City and at the Poinsettia Lane Commuter Rail Station, according to
MHCP Volume 3 standards, can be 'met among the signatories to the IA (City, Service, and/or
Department). The single known occurrence of this plant in the City will not be directly impacted
by the implementation of the plan. There is a possibility that new populations of San Diego
button-celery will be found as surveys are conducted on sites with suitable habitat. San Diego
button-celery is a narrow endemic and will be conserved accordingly. Thus, development that
would adversely affect this species could not be permitted under Carlsbad's HMP until such
coverage is received by the City. The process for initiating coverage for species in Table 3 is the
30 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 302
same as for species in Table 2 and requires the City to document in writing that the necessary
conditioqs of coverage will be met with written concurrence from the Wildlife Agencies.
-
Zndirect Efsects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station and increased development near the San Marcos vernal pools
will increase the amount of foot and bicycle traffic in the area. This increase in activity could
lead to trampling of sensitive plants and the introduction of invasive exotic plants. The pools
will be most vulnerable to these impacts during the wet winter and spring months.
As the density of residential housing around these vernal pool complex increases these pools will
become isolated from other vernal pool complexes and the existing matrix of undeveloped
habitat. Pollinators and seed dispersal agents may have insufficient habitat to survive as the
pools become surrounded by development. Due to the spiny bracts that surround the
inflorescence on San Diego button-celery this plant has a much greater chance of being dispersed
by animals than other vernal pool plants. The isolation of these pools will limit the range
expansion of this species from areas in the subarea, such as the pools at the Hieatt property and
the restored pools located along El Camino Real. It will also preclude the transfer of plant
material between the Carlsbad pools and the pools in San Marcos.
In addition, the run-off from adjacent residential development will indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year
round fresh water marsh, whereas not enough water will not provide vernal pool plants the
moisture they need to flower and reproduce. Both pollutants and sediment load will likely
impact the success of these pools and, therefore, the water quality will need to be monitored.
The MHCP Subregional Plan and the City’s Subarea Plan requires the long-term monitoring and
management of these vernal pool complexes.
Conclusion
We have concluded that the proposed action will not directly impact any currently known San
Diego button-celery plants. Although direct impacts to any new populations of San Diego
button-celery could occur throughout the MHCP Subregional Plan, the plans require the narrow
endemic policy to be applied to this species. In addition, since the plans provides assurances that
the known populations and any new populations of San Diego button-celery will be monitored
and managed consistent with the MHCP Management and Monitoring Plan (Volume 3) and
coverage for this species to the City does not begin until documentation that provides these
assurances is provided to the Service and Department, the plan will detect and minimize any
negative impacts that are affecting San Diego button-celery . The avoidance, minimization,
and/or mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan will
reduce any impacts that may occur to this species. Additionally, this species will benefit from
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
the habitat that the City’s Subarea Plan will preserve in perpetuity. This Preserve will be
adaptive17 managed, per the measures included in the MHCP Subregional Plan and City’s
Subarea Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the MHCP Subregional Plan and City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
303 -
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Zva hayesiana (San Diego marsh-elder)
- 304
Status of'the SDecies
Listing Status
San Diego Marsh-elder is not a state or a federally listed species. The California Native Plant
Society places this species on list 2 with a R-E-D (Rarity-Endangerment-Distribution) code of 2-
2-1, and a California Natural Diversity Data Bank ranking of G3S2.2.
Species Description
Zva hayesiana is a member of the Asteraceae (sunflower) family and belongs to the wormwood
genus. It is a perennial shrub growing to less than one meter with brown stems, with simple
leaves with blunt tips, and possesses yellow flowers in a raceme-like inflorescence. This species
is distinguished from other Zva species by its free phyllaries.
Distribution
San Diego marsh-elder is restricted to southwestern San Diego County and northern Baja
California, Mexico (Skinner and Pavlik 1994). In San Diego County, this species occurs from
San Marcos south to the U.S.-Mexican border. Reported localities include San Marcos Creek,
Encinitas Creek, Escondido Creek, San Elijo Lagoon, San Dieguito River Valley, Rancho Santa
Fe, Los Pefiasquitos Canyon, Proctor Valley, Otay River Valley, Tijuana River Valley, and Otay
Mesa, among others (Beauchamp 1986; Ogden 1998). Populations of this species are found in
Carlsbad (San Marcos Creek, Encinitas Creek) and San Marcos (San Marcos Creek, Encinitas
Creek).
Habitat Afinity
San Diego marsh-elder is found in moist or alkaline places in the coastal region, particularly
along intermittent streams. Open riparian canopies and sandy alluvial embankments are common
constituents, as well as,steep watercourses in the southern portion of the County.
Life History
San Diego marsh-elder is a perennial subshrub. It is wind pollinated (Stebbins 1974), and seeds
are self-dispersed. This species is commercially propagated and has been successfully planted in
restoration projects.
Population Trend
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The population of San Diego marsh elder is considered stable, but potentially affected by
modifications and degradation of coastal drainages (Reiser 1996). It is possible that existing
populatidns could be expanded because this plant exhibits rigorous growth. There is also
potential for planned introductions of this species in riparian restoration projects.
305 -
Threats
The primary threats to this species are waterway channelization, development of riparian zones,
and edge effects.
Environmental Baseline
San Diego marsh-elder occurs in riparian areas of Carlsbad, Encinitas, and San Marcos within
the MHCP. Major populations and critical locations of this species occur in San Marcos Creek
and Encinitas Creek in both Carlsbad and San Marcos. There are 165 acres of San Diego marsh-
elder habitat, alkali marsh, in the MHCP planning area and 157 acres of this are within the FPA.
All of the locations of San Diego marsh-elder in the City occur on previously permitted projects.
These populations are primarily found along San Marcos Creek and Encinitas Creek, two of
which are considered major populations and critical locations. Bstorically, three populations
occurred on the Villages of La Costa property and one population occurred on the Rancho Verde
property. One of the three populations that occurred on the Villages of La Costa property was
conserved, the other two are presumed extirpated. The population that occurred on the Rancho
Verde property was conserved and is currently extant.
Effects of the Action
Direct Efsects
The MHCP Subregional Plan requires the following conditions be met by a city to receive
coverage for this species:
1. The major population and critical location along Encinitas Creek in San Marcos must be
conserved in accordance with wetland and critical location policies and managed as part
of the preserve system.
Declining populations must be enhance, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 306 -
Direct impact to San Diego marsh-elder will occur as a result of the MHCP Subregional Plan,
however, the loss is expected to be minimal because the two location points in the City of
Encinitas will be conserved in its entirety (100 percent), one of the populations in the City of San
Marcos will be conserved in its entirety (100 percent), and the other population in the City of San
Marcos will be conserved in accordance with the critical location policy. In addition, 157 acres
of the 165 acres of alkali marsh habitat in the MHCP planning area are within the FPA and all
165 acres will be conserved due to the wetland protection policy.
No direct impacts to San Diego marsh-elder are expected to occur in the City of Carlsbad.
However, the City of Carlsbad would not receive coverage for this species until the Cities of
Encinitas and San Marcos have valid lO(a)l(B) permits for their Subarea Plans from the Service
with this species covered. In addition, the City of Carlsbad will not receive coverage for this
species until they can document they have access and the funds available to manage and monitor
this species as described in the MHCP Volume 3 and the OSMP. Thus, development that would
adversely affect this species could not be permitted under Carlsbad’s HMP until such coverage is
received by the City. The process for initiating coverage for species in Table 3 is the same as for
species in Table 2 and requires the City to document in writing that the necessary conditions of
coverage will be met with written concurrence from the Wildlife Agencies.
Indirect Efsects
These populations will likely be impacted by invasive exotics and increased pedestrian traffic
because they occur near the preserve edge. However, San Diego marsh-elder will benefit from
the management and monitoring outlined in the MHCP and the MHCP and City’s no-net-loss of
wetlands policy. The MHCP and City’s plan will minimize edge effects from trampling,
vehicular traffic, dumping, and invasive exotic species. These plans also recognize the
importance of maintaining the appropriate hydrological conditions. These measures will help to
preserve existing populations of San Diego marsh-elder. Management and monitoring of this
species to MHCP standards will help to avoid and minimize such indirect effects. However, the
City would not be able to initially fund or gain access for management and monitoring for half of
both major and critical populations of this species in the City until a regional funding source, or
some other additional funds, are available. Because of this, coverage for this species is not being
proposed until the City of Carlsbad can document they have access and the funds available to
manage and monitor this species as described in the MHCP Volume 3 and the OSMP.
Conclusion
We have concluded that the MHCP Subregional Plan will directly and indirectly impact San
Diego marsh-elder in the City of San Marcos as described above. However, 75 percent of all
known location points will be conserved and 100 percent of San Diego marsh-elder habitat will
be conserved. In addition, the MHCP Subregional Plan assures that all remaining populations of
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
San Diego marsh-elder will be monitored and managed consistent with the MHCP Management
and Monitoring Plan (Volume 3). Coverage for this species to the City does not begin until the
Cities of Encinitas and San Marcos receive coverage under a valid lO(a)l(B) permit and the City
of Carlsbad can provide documentation to the Service and Department that adequate access and
funding is available. The avoidance, minimization, andor mitigation measures included in the
MHCP Subregional Plan and City’s Subarea Plan will reduce any impacts that may occur to this
species. This species will also benefit from the habitat that the MHCP Subregional Plan ill
preserve in perpetuity. This Preserve will be adaptively managed, per the measures included in
the MHCP Subregional Plan and the City’s Subarea Plan which will further reduce the indirect
effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the MHCP Subregional Plan and the City’s
Subarea Plan are not likely to jeopardize the continued existence or recovery of this species.
307 -
’
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Myosurus minimus ssp. apus (Little mousetail)
Status of the Species
- 308
Listing Status
Little mousetail is neither a State nor a Federally listed species. This species is on the California
Native Plant Society’s list 3 with a R-E-D (Rarity-Endangerment-Distribution) code 2-3-2, and a
California Natural Diversity Data Bank ranking of G5T2QS2.2. Little mousetail is considered a
MHCP narrow endemic species and wetland obligate.
Species Description
Myosurus minimus ssp. apus, a member of Ranunculaceae (buttercup) family, was originally
described by Greene (1885). The nomenclature for the species was revised in by Campbell
(1952) to its currently acceptable taxonomic status. Little mousetail is a small (2-12 centimeters
in height), tufted annual, emerging from fibrous roots. Thread-like, oblanceolate leaves give way
to a peduncle inflorescence with white to green flowers.
There is some confusion regarding the taxonomy for this species. One theory is that little
mousetail is a stabilized hybrid between M. minimus and M. sessilis (Skinner and Pavlik, 1994).
It is difficult to distinguish between little mousetail (M. minimus ssp. apus) and M. sessiZis
(CNDDB).
Distribution
Little mousetail has a relatively widespread distribution, occurring in Butte, Colusa, Solano,
Contra Costa, Alameda, Stanislaus, Kern, Riverside, San Bernardino, and San Diego counties, as
well as in Oregon and Baja California, Mexico (Skinner and Pavlik 1994). The historic
distribution is not well known. In San Diego County, the species is restricted to Camp Pendleton
(Stuart Mesa, Wire Mountain), Carlsbad, Ramona, the mesas north of San Diego, and Otay
Mesa. Within the MHCP planning area, little mousetail only occurs in the Poinsettia Lane vernal
pools in Carlsbad.
Habitat Afinity
Little mousetail occurs in alkaline soil on alkaline substrate under vernally-flooded conditions in
vernal-pool habitats. This cryptic species typically grows in the deeper portions of vernal pool
basins sprouting immediately after the surface water has evaporated. The stature of plants and
population densities of Myosurus minimus change dramatically from wet to dry years. Soils are
mapped as Huerhuero loam for both little mousetail sites near Dillon Road in the southwestern
portion of the county, and for Stewart Mesa in the northwestern portion of the county. Bosanko
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
clays are reported for a site in the Gavilan Hills of Riverside County.
- 309
Little mousetail develops small greenish flowers from April through May on the Santa Rosa
Plateau (Munz 1974). Within the Salt Creek drainage, little mousetail blooms earlier, coinciding
with the rains and cooler temperatures, often in March and April. Stone (1959) found that
members of the genus Myosurus were self-pollinated and that many "biotypes" could co-exist
sympatrically and yet maintain floral isolation, Insects appear to play only a minor role in
reproduction (Stone 1959). Each plant produces about 70 achenes, each with a single seed
(Campbell 1952). Seeds are viable for only a short number of years (Stone 1959).
.
Population Trend
Little mousetail is declining throughout its limited range in southern California (Reiser 1996).
Most southern California populations are relatively small. The two largest concentrations of
little mousetail are on Otay Mesa of San Diego County and at Salt Creek west of Hemet in
Riverside County (Dudek and Associates 2000).
Threats
Threats to this species are many and include vehicular traffic, grazing and trampling by livestock,
land conversion to farming, edge effects, habitat destruction and fragmentation from urban and
agricultural development, pipeline construction, alteration of hydrology and flood plain
dynamics, excessive flooding, channelization, off-road vehicle activity, weed abatement, fire
suppression practices (including discing and plowing), and competition from alien plant species
(U.S. Fish and Wildlife Service 1998b).
Environmental Baseline
Little mousetail occurs at only one location within the MHCP. This location is within the
Carlsbad subarea at the vernal pools at Poinsettia Lane Commuter Station. The status of this
species at the Poinsettia Lane location is unknown at present. This population provides a
stepping stone between populations of little mousetail on Camp Pendleton Marine Corps Base
and populations in the southern part of San Diego County. It is possible that this plant exists at
other vernal pools in the subarea, however, these pools have been surveyed and little mousetail
has not been reported.
Effects of the Action
Direct Efsects
\
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The MHCP Subregional plan requires the following conditions be met for a city to receive
coverage for this, species:
3 10 -
1.
2.
3.
4.
5.
All conserved populations must be adequately managed to control edge effects and avoid
adverse changes to vernal pools and their watersheds. Stabilize preserved populations by
removing impacts or potential impacts, and excluding adverse activities within preserve
areas and within the watersheds of vernal pools (e.g., trampling, vehicular or recreational
traffic, illegal dumping, invasive exotic plants, water pollution, alteration of hydrology,
and collecting). Regulate the use of toxic substances (e.g., herbicides, pesticides) and
control nonnative competitive species in the vicinity of vernal pools.
The MHCP Narrow Endemics Policy must be applied to all populations of this species,
including those already known and all found in the future.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
If not already established by the region by another entity, the MHCP management
program must establish a seed bank as a guarantee against extinction and to provide
source material for conservation and research activities. A seed bank must be established
within 15 years of permit issuance. Collections should be based on established guidelines
and subject to seed availability. Collected seed should be stored at an established seed
bank facility (e.g. Rancho Santa Ana Botanic Garden or San Diego Wild Animal Park).
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
No direct impacts will occur to the one little mousetail population from either the MHCP
Subregional Plan or the City’s Subarea Plan since it occurs in a 100 percent preserve area. In
addition, applying the above conditions throughout the MHCP planning area will result in a
majority of any new species points identified being preserved since the narrow endemic policy is
required, which would require no more than 20 percent gross cumulative loss outside of the PA.
The City of Carlsbad will not receive coverage for this species until documentation is provided
that assures the above conditions, including management and monitoring of this species in
perpetuity throughout the City and at the Poinsettia Lane Commuter Rail Station, according to
MHCP Volume 3 standards, can be met among the signatories to the IA (City, Service, and/or
Department). Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 3 is the same as for species in Table 2 and requires the City to
document in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
3 10
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The single known occurrence of this plant in the City will not be directly impacted by the
implementation of the plan. There is a possibility that new populations of San Diego little
mousetaii will be found as surveys are conducted on sites with suitable habitat. Little mousetail
is a narrow endemic and will be conserved accordingly.
311 -
Indirect Eflects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station will increase the amount of foot and bicycle traffic in the area.
This increase in activity could lead to trampling of sensitive plants and the introduction of
invasive exotic plants. The pools will be most vulnerable to these impacts during the wet winter
and spring months. As the density of residential housing around this vernal pool complex
increases, these pools will become isolated from other vernal pool complexes and the existing
matrix of undeveloped habitat in Carlsbad. Pollinators and seed dispersal agents may have
insufficient habitat to survive as the pools become surrounded by development.
In addition, the run-off from adjacent residential development will indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year-
round fresh water marsh, whereas not enough water will not provide vernal pools plants the
moisture they need to flower and reproduce. Both pollutants and sediment load will likely
impact the success of these pools and, therefore, the water quality will need to be monitored.
The MHCP Subregional Plan and the City’s Subarea Plan requires the long-term monitoring and
management of this vernal pool complex.
Conclusion
We have concluded that the proposed action will not directly impact the one known population
of little mousetail in the MHCP planning area. Although direct impacts to any new populations
of little mousetail could occur throughout the MHCP Subregional Plan, the plans require the
narrow endemic policy to be applied to this species. In addition, since the plans provides
assurances that the known populations and any new populations of little mousetail will be
monitored and managed consistent with the MHCP Management and Monitoring Plan (Volume
3) and coverage for this species to the City does not begin until documentation that provides
these assurances is provided to the Service and Department, the plan will detect and minimize
any negative impacts that are affecting little mousetail. The avoidance, minimization, and/or
mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan will
reduce any impacts that may occur to this species. Additionally, this species will benefit from
the habitat that the City’s Subarea Plan will preserve in perpetuity. This Preserve will be
adaptively managed, per the measures included in the MHCP Subregional Plan and City’s
Subarea Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
that the MHCP Subregional Plan and City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
312 -
3 12
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Navarretia fossalis (Spreading navarretia)
- 313
Status of’the Species
Listing Status
Spreading navarretia was listed as threatened on October 13, 1998 (63 FR 54975). Critical
habitat has not been designated for this species. A vernal pool recovery plan which included
spreading navarretia was completed in September 1998 (U.S. Fish and Wildlife Service 1998b).
Species Description
Navarretia fossalis, a member of the Polemoniaceae (phlox) family, was first described by Reid
Moran (1977) based on a specimen he collected in 1969 near La Misi6n in northwestern Baja
California. It is a low, mostly spreading or ascending, annual herb, 10 to 15 centimeters (4 to 6
inches ) tall. The lower portions of the stems are mostly glabrous. The leaves are soft and finely
divided, 1 to 5 centimeters (0.4 to 2 inches) long, and spine-tipped when dry. The inflorescence
consists of a compact, compound cyme of 15 to 50 small (4.5 to 6.5 millimeters), white flowers
with linear petals. The fruit is an ovoid, 2-chambered capsule (Day 1996, Moran 1977).
There are approximately 30 species in the genus Navarretia, several of which occur within the
range of spreading navarretia. Two of them, Navarretia intertexta (needleleaf navarretia) and
Navarretia prostrata (prostrate navarretia), can occur in similar habitat. Spreading navarretia
can be confused with, and has been misidentified as, prostrate navarretia (Moran 1977).
Spreading navarretia is distinguished by its linear or narrowly ovate corolla lobes, erect habit,
cymose inflorescence, the size and shape of the calyx, and the position of the corolla relative to
the calyx (Day 1996, U.S. Fish and Wildlife Service 1998b).
Distribution
Historical records indicate that spreading navarretia once ranged from as far north as San Luis
Obispo County south to Baja California, Mexico (U.S. Fish and Wildlife Service 1998b). The
current distribution of this species is from northwestern Los Angeles County and western
Riverside County, south through coastal San Diego County, California to San Quintin in
northwestern Baja California, Mexico, from near sea level to 1,300 meters (Day 1996, Munz
1974). In San Diego County, this species is found below 450 meters in Carlsbad, San Marcos,
Ramona, and on Otay Mesa (Ogden Environmental et al. 2000). Spreading navarretia occurs in
the Poinsettia Lane vernal pools in the City of Carlsbad and in the vernal pools within the City of
San Marcos.
Ha b itat Afin i ty
3 13
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Spreading navarretia is primarily associated with vernal pools (Day 1996, U.S. Fish and Wildlife
Service 1,998b). This species occasionally occurs in ditches and other artificial depressions,
which often occur in degraded vernal pool habitat (Moran 1977). Spreading navarretia also
occurs in alkali grassland habitat along the San Jacinto River in Riverside County (US. Fish and
Wildlife Service 1998b).
3 14 -
Life History
Spreading navarretia flowers from May through June. No studies have been conducted for this
species regarding reproduction. Specific data regarding pollinators and seed viability are lacking.
The fruit of this species consists of indehiscent capsules (2 to 3 millimeters) containing 5 to 25
seeds. The seeds become mucilaginous when wet (Moran 1977). Dispersal in this species has
not been studied. After fruiting, this species fades rapidly and can be difficult to detect late in the
dry season or in dry years. The number of individuals of spreading navarretia at a given
population site varies annually in response to the timing and amount of rainfall and temperature.
Population Trend
Spreading navarretia is declining throughout much of its range (Reiser 1996). Fewer than 30
populations exist in the United States, however, nearly 60 percent of these populations are
concentrated in three locations: Otay Mesa in southern San Diego County, along the San Jacinto
River in western Riverside County, and near Hemet in Riverside County (U.S. Fish and Wildlife
Service 1998b). The two largest populations occur in Riverside County and have been estimated
to support 300,000 and 75,000 individuals. However, each of these populations occupies less
than 3 hectares (8 acres) of habitat. The majority of populations contain fewer than 1,000
individuals and occupy less than 0.5 hectare (1 acre) of habitat. The Service estimates that less
than 120 hectares (300 acres) of habitat in the United States is occupied by this species (US. Fish
and Wildlife Service 1998b). In Mexico, spreading navarretia is known from fewer than 10
populations clustered in three areas: along the international border, on the plateaus south of the
Rio Guadalupe, and on the San Quintin coastal plain (Moran 1977).
Threats
Spreading navarretia and its habitat are threatened by habitat destruction and fragmentation from
urban and agricultural development, pipeline construction, road construction, alteration of
hydrology and flood plain dynamics, excessive flooding, channelization, off road vehicle activity,
trampling by cattle and sheep, weed abatement, fire suppression practices (including discing and
plowing), and competition from alien plant species (U.S. Fish and Wildlife Service 1998b).
Edge effects associated with urbanization include alterations in the watershed that may reduce
the source of water and encourage invasion of habitat by upland plant species.
Environmental Baseline
3 14
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Within the MHCP there are two known populations of spreading navarretia; one is found in the
vernal pools in San Marcos and the other is found in Carlsbad at the Poinsettia Lane vernal pools.
Both of these populations are considered to be major populations as well as critical locations.
However, all of the populations in San Marcos are in the major amendment area. Thus, the
conditions of the MHCP for this species will not apply to these areas and adverse affects to these
areas will not be covered by the MHCP plan. However, the pools in San Marcos on the Bent
Avenue property where spreading navarretia were observed in the pools in 1993 will be
conserved. A U.S. Army Corps of Engineers permit (Corps Perrnit No. 200001 113-TCD) was
issued to South Coast Development on December 15,2000, which required a the long-term
preservation of 4.5 acres of vernal pool watershed on the Bent Avenue property via a recorded
conservation easement over the areas to be conserved. It is our understanding that the
conservation easement has not yet been recorded.
315 -
The pools at Poinsettia Lane have been degraded by agriculture and construction of the train
station, however, they continue to function as vernal pool habitat. The status of spreading
navarretia at this site is unknown, however, it is believed that this population is extant. The
Poinsettia Lane pools and their watersheds occur on both North County Transit District (NCTD)
land and private property associated with the Water’s End housing development project. The
Service formally consulted under section 7 of the Act (1-6-94-F-9) with the U.S. Army Corps of
Engineers on the adverse affects associated with the train station on this species (U.S. Fish and
Wildlife Service, 1994b). In response to this consultation, NCTD agreed to grant a conservation
easement over all the pools on their property to the California Department of Fish and Game and
provide a management plan with an endowment for the management of the pools. These
obligations remain outstanding, however, active progress is being made. The Water’s End
development has agreed to avoid impacts to the vernal pool watersheds and will provide an
easement over the pool watersheds on their property to the City with California Department of
Fish and Game and the US Fish and Wildlife Service as third party beneficiary. In addition, they
are providing $100,000 of funds to the City for an endowment to manage and monitor the
Poinsettia Lane pool watersheds. The California Department of Fish and Game and the City of
Carlsbad will ensure that these pools and their watersheds are managed to MHCP standards.
It is possible that this plant exists at other vernal pools in the MHCP planning area, however, no
spreading navarretia was detected during past surveys.
Effects of the Action
Direct Eflects
The MHCP Subregional plan requires the following conditions be met for a city to receive
coverage for this species:
315
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 316
1.
2.
3.
4.
5.
6.
-
The major population and critical location of spreading navarretia in San Marcos must be
conserved at a level consistent with the critical location policy and managed as part of the
preserve system.
All conserved populations must be adequately managed to control edge effects and avoid
adverse changes to vernal pools and their watersheds. Stabilize preserved populations by
removing impacts or potential impacts, and excluding adverse activities within preserve
areas and within the watersheds of vernal pools (e.g., trampling, vehicular or recreational
traffic, illegal dumping, invasive exotic plants, water pollution, alteration of hydrology,
and collecting). Regulate the use of toxic substances (e.g., herbicides, pesticides) and
control nonnative competitive species in the vicinity of vernal pools.
The MHCP Narrow Endemics Policy must be applied to all populations of this species,
including those already known and all found in the future.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
A seed bank must be established as a guarantee against extinction and to provide source
material for conservation and research activities. Collections should be based on
established guidelines and subject to seed availability. Collected seed should be stored at
an established seed bank facility (e.g. Rancho Santa Ana Botanic).
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
Applying the above conditions throughout the MHCP planning area will result in a majority of
species points being conserved at a level of 100 percent, since most of the points are in the FPA
and the San Marcos species points need to be conserved consistent with the critical location
policy for narrow endemics. Any new species points identified would need to follow the narrow
endemic policy, which would require no more than 20 percent gross cumulative loss outside of
the FPA.
The City of Carlsbad will not receive coverage for this species until documentation is provided
that assures the above conditions, including management and monitoring of this species in
perpetuity throughout the City and at the Poinsettia Lane Commuter Rail Station, according to
MHCP Volume 3 standards, can be met among the signatories to the IA (City, Service, and/or
Department). Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 3 is the same as for species in Table 2 and requires the City to
document in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
3 16
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The single known occurrence of this plant in the City will not be directly impacted by the
implementation of the plan. There is a possibility that new populations of spreading navarretia
will be fiund as surveys are conducted on sites with suitable habitat. Spreading navarretia is a
narrow endemic and will be conserved accordingly.
317 -
Indirect Efects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station and increased development near the San Marcos vernal pools
will increase the amount of foot and bicycle traffic in the area. This increase in activity could
lead to trampling of sensitive plants and the introduction of invasive exotic plants. The pools
will be most vulnerable to these impacts during the wet winter and spring months.
As the density of residential housing around this vernal pool complex increases these pools will
become isolated from other vernal pool complexes and the existing matrix of undeveloped
habitat. Pollinators and seed dispersal agents may have insufficient habitat to survive as the
pools become surrounded by development.
In addition, the run-off from adjacent residential development may indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year-
round fresh water marsh, where as not enough water will not provide vernal pool plants the
moisture they need to flower and reproduce. Both pollutants and sediment load will likely
impact the success of these pools and, therefore, the water quality will need to be monitored.
The MHCP Subregional Plan and the City’s Subarea Plan requires the long-term monitoring and
management of these vernal pool complexes.
Conclusion
We have concluded that the proposed action will not directly impact any currently known
spreading navarretia plants. Although direct impacts to any new populations of spreading
navarretia could occur throughout the MHCP Subregional Plan, the plans require the narrow
endemic policy to be applied to this species. In addition, since the plans provides assurances that
the known populations and any new populations of spreading navarretia will be monitored and
managed consistent with the MHCP Management and Monitoring Plan (Volume 3) and coverage
for this species to the City does not begin until documentation that provides these assurances is
provided to the Service and Department, the plan will detect and minimize any negative impacts
that are affecting spreading navarretia. The avoidance, minimization, and/or mitigation measures
included in the MHCP Subregional Plan and City’s Subarea Plan will reduce any impacts that
may occur to this species. Additionally, this species will benefit from the habitat that the City’s
Subarea Plan will preserve in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan and City’s Subarea Plan, which will further
reduce the indirect effects and benefit the species. After reviewing the current status of this
3 17
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
species, the environmental baseline for the action area, the effects of the proposed action, and the
cumulative effects, it is the Service’s biological opinion that the MHCP Subregional Plan and
City’s Subarea Plan are not likely to jeopardize the continued existence or recovery of this
species.
318 -
318
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Orcuttia califomica (California Orcutt grass)
- 3 19
Status of ’the Species
Listing Status
California Orcutt grass was Federally listed as endangered on August 3, 1993 (58 FR 41391) and
was State listed as endangered in California in September 1979. Critical habitat was not
designated for this species. A vernal pool recovery plan, which included California Orcutt grass,
was completed in September 1998 (U.S. Fish and Wildlife Service 1998b). This species is on the
California Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code
of 3-3-2, and a California Natural Diversity Data Bank ranking of G2S2.1. California Orcutt’s
grass is considered a MHCP narrow endemic species.
Species Description
Orcuttia califomica, one of five. species in the genus Orcuttia in the Poaceae (grass) family, was
first collected by Charles Orcutt and described by George Vasey (1886). California Orcutt grass
is a small, annual, bright gray-green grass that reaches about 10 centimeters (4 inches) in height
and secretes a sticky exudate. A secretion on all leaves is first glistening and watery but as the
plant matures the secretion becomes thicker, denser and brownish. This secretion, believed to
aid in water conservation during the warm spring and hot summer months, is aromatic and bitter
tasting and may serve to deter animal predation (e.g., grasshoppers, etc.) (Crampton 1959, Griggs
198 1). Inflorescence consist of seven spikelets arranged in two ranks, with the upper spikelets
overlapping on a somewhat twisted axis. California Orcutt grass is differentiated from other
species in the genus by the following characteristics: teeth of lemma (bract enclosing the floret),
the teeth sharp-pointed or with awns, culms (stems) usually prostrate, caryopsis (fruit); plants
sparingly pilose (bearing soft and straight spreading hairs); and, spikelets remote on the axis
below, crowded toward the apex.
Distribution
The California Orcutt grass was once commonly found in the volcanic terrace and vernal pool
system in Los Angeles, Riverside and San Diego Counties in southern California. Today, most
of these vernal pools systems have been drained and or filled, and resulting changes in local
hydrology patterns have limited this vernal pool-dependent species to only a few locations where
vernal pools have not yet been disturbed. The current range of California Orcutt grass is from the
Carlsberg vernal pool located in Moorpark in Ventura County, south to the vernal pools around
San Quintin, Baja California, Mexico (US. Fish and Wildlife Service 1998b). Its elevational
range is from near sea level to 625 meters (Hickman 1996).
3 19
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
California Orcutt grass is known from a single vernal pool complex (Carlsberg) in Ventura
County apd a single vernal pool complex (Cruzan Mesa) in Los Angeles County. In Riverside
County California Orcutt grass occurs on the Santa Rosa Plateau, in Skunk Hollow, and at a site
near Hemet. This species once occurred near Murrieta Hot Springs (Riverside County), but this
population has been extirpated. In San Diego County, California Orcutt grass is found in two
vernal pools on Marine Corps Air Station (MCAS) Miramar, in four vernal pool complexes on
Otay Mesa, and in the Poinsettia vernal pools in the City of Carlsbad (U.S. Fish and Wildlife
Service 1998b).
320 -
Habitat Afinity
All known Californica Orcutt grass localities are associated with vernal pools (Crampton 1959,
Reeder 1996, California Native Plant Society (CWS) 2001, U.S. Fish and Wildlife Service
1998b). California Orcutt grass tends to grow in the deeper and wetter portions of the vernal
pool basins, but this annual does not show much growth until the basins become somewhat
desiccated (U.S. Fish and Wildlife Service 1993b, Reiser 1996). Griggs and Jain (1983)
observed that the individual plants found in the deeper portions of the pools tend to be more fully
developed and larger than individuals at the pool margins. In Riverside County, this species is
found in southern basaltic claypan vernal pools at the Santa Rosa Plateau, and alkaline vernal
pools at Skunk Hollow and at Salt Creek west of Hemet (Reiser 1996). This species is
considered a wetland obligate.
Life History
California Orcutt grass flowers from April through June (Munz 1974) and appears to be strongly
adapted to wind pollination. Stamens are 2 to 3 centimeters long and the species is protandrous
(i.e., anthers develop before the stigma is receptive). In combination with the protandry, this
species is believed to be an out crosser (Griggs and Jain 1983). Orcuttia floral spikelets are of
indeterminate growth, the duration of which is dependant on the duration of favorable
environmental conditions.
During field observations, Griggs (1 98 1) discovered fungi-covered seeds germinating
approximately two weeks following pool inundation. Griggs (198 1) experimented with various
methods of seed gemination in the laboratory, observing 'that germination only occurred when
fungi covered the seeds (often at a rate of 90 to 100 percent). Studies conducted by Keeley
(1 988) revealed that anaerobic conditions promote germination of California Orcutt grass fruits
but fungicide treatment appears to inhibit germination (fungal growth developed on the seeds in
all other treatments). A dependence on fungus and anaerobic conditions for germination is
consistent with conditions in water-filled vernal pools and may explain how germination is cued
during years of sufficient rainfall (Keeley 1988).
320
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Studies of other Orcuttia species indicate that the number of fruits produced per plant is highly
variable within a population and variation in seed production between seasons can vary by two-
or three-;old. This is not unexpected given the dependence of Orcuttia species on a synchrony of
environmental conditions (timing and duration of rainfall, temperature, etc.) (Griggs and Jain
1983). California Orcutt grass seeds can remain dormant for at least three to four years and
possibly longer, germinating in the spring only after flooding of the vernal pools (Griggs 1981,
Griggs and Jain 1983). California Orcutt grass remains intact and upright upon senescence. The
first heavy rainstorms of the late fall or early winter cause the plants to fall apart, releasing the
fruit formed the previous summer. The fruits either become firmly attached to the muddy surface
of the pool or float to the bottom if the pool is inundated (Griggs 1981). California Orcutt grass
seedlings grow for several weeks submerged, producing leaves that float on the surface. After
the pools have dried California Orcutt grass produces a new set of foliage that will last for one to
two months, until flowering and fruiting have occurred (Griggs 1981, Keeley 1988).
321 -
Population Trend
California Orcutt grass is declining throughout its range and is considered one of the rarest plants
in San Diego County (Reiser 1996). In 1979, this species occurred on Otay Mesa in 7 pool
groups containing 34 vernal pools (U.S. Fish and Wildlife Service 1993b). By 1986, agricultural
plowing had destroyed 11 of these vernal pools. By 1993, California Orcutt grass occurred in
only 2 vernal pool groups, which contained a total of 10 vernal pools. The vernal pools in
Carlsbad at Poinsettia Lane Train Station are currently under a conservation easement that was
dedicated in association with the construction of the Poinsettia Lane Train Station by the North
County Transit District (NCTD) (U.S. Fish and Wildlife Service, Biological Opinion 1-6-94-F-
9). Although these pools are currently protected, they are isolated and surrounded by
development. In 1993, floristic surveys of the vernal pools at Poinsettia Lane indicated that
California Orcutt grass only occurred in about 25 percent of the transects and on less than 1 acre
in one vernal pool complex (Dudek and Associates 1993).
Threats
Loss of vernal pool habitat in the County of San Diego is estimated at 95 to 97 percent (Bauder
1986, Bauder and McMillan 1998). This species is threatened by habitat destruction and
fragmentation from urban and agricultural development, pipeline construction, alteration of
hydrology and flood plain dynamics, excessive flooding, off road vehicle activity, trampling by
cattle, sheep and humans, weed abatement, fire suppression practices (including discing and
plowing), and competition from alien plant species as well as other vernal pool species (U.S. Fish
and Wildlife Service 1998b).
Environmental Baseline
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
A single population of California Orcutt grass exists within the MHCP. This population occurs
within the Carlsbad subarea at the Poinsettia Lane Commuter Rail Station. The vernal pool
complex at this location occurs in a narrow band running north to south along the train tracks.
Both the train tracks and adjacent development have altered the hydrology of this area. The
pools have exotic weeds on their margins and face the threat of run-off from an adjacent
development. The current status of California Orcutt grass at this location is unknown.
California Orcutt grass is found in a limited number of vernal pools that hold water for a longer
than average time period. Because of the rarity of this type of pool, it is not expected that this
species will be found elsewhere in the MHCP.
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Effects of Action
Direct Efects
The MHCP Subregional plan requires the following conditions be met for a city to receive
coverage for this species:
1. All conserved populations must be adequately managed to control edge effects and avoid
adverse changes to vernal pools and their watersheds. Stabilize preserved populations by
removing impacts or potential impacts, and excluding adverse activities within preserve
areas and within the watersheds of vernal pools (e.g., trampling, vehicular or recreational
traffic, illegal dumping, invasive exotic plants, water pollution, alteration of hydrology,
and collecting). Regulate the use of toxic substances (e.g., herbicides, pesticides) and
control nonnative competitive species in the vicinity of vernal pools.
The MHCP Narrow Endemics Policy must be applied to all populations of this species,
including those already known and all found in the future.
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
A seed bank must be established as a guarantee against extinction and to provide source
material for conservation and research activities. Collections should be based on
established guidelines and subject to seed availability. Collected seed should be stored at
an established seed bank facility (e.g. Rancho Santa Ana Botanic Garden).
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
4.
5.
No direct impacts will occur to the one California Orcutt grass population from either the MHCP
Subregional Plan or the City’s Subarea Plan since it occurs in a 100 percent preserve area. In
addition, applying the above conditions throughout the MHCP planning area will result in a
majority of any new species points identified being preserved since the narrow endemic policy is
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
required, which would require no more than 20 percent gross cumulative loss outside of the FPA.
323 -
The City’of Carlsbad will not receive coverage for this species until documentation is provided
that assures the above conditions, including management and monitoring of this species in
perpetuity throughout the City and at the Poinsettia Lane Commuter Rail Station, according to
MHCP Volume 3 standards, can be met among the signatories to the IA (City, Service, and/or
Department). Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 3 is the same as for species in Table 2 and requires the City to
document in writing that the necessary conQtions of coverage will be met with written
concurrence from the Wildlife Agencies.
The single known occurrence of this plant in the City will not be directly impacted by the
implementation of the plan. Any new populations of California Orcutt grass will be treated as a
narrow endemic and conserved accordingly.
Indirect Effects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station will increase the amount of foot and bicycle traffic in the area.
This increase in activity could lead to trampling of sensitive plants and the introduction of
invasive exotic plants. The pools will be most vulnerable to these impacts during the wet winter
and spring months. As the density of residential housing around this vernal pool complex
increases these pools will become isolated from other vernal pool complexes and the existing
matrix of undeveloped habitat in Carlsbad. Pollinators and seed dispersal agents may have
insufficient habitat to survive as the pools become surrounded by development.
In addition, the run-off from adjacent residential development may indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year
round fresh water marsh, whereas not enough water will not provide the California Orcutt grass
the moisture it needs to complete its lifecycle. Both pollutants and sediment load will likely
impact the success of these pools and, therefore, the water quality will need to be monitored.
The MHCP Subregional Plan and the City’s Subarea Plan requires the long-term monitoring and
management of this vernal pool complex.
Conclusion
We have concluded that the proposed action will not directly impact the one known population
of California Orcutt grass in the MHCP planning area. Although direct impacts to any new
populations of California Orcutt grass could occur throughout the MHCP Subregional Plan, the
plans require the narrow endemic policy to be applied to this species. In addition, since the plans
provides assurances that the known populations and any new populations of California Orcutt
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 3 24
grass will be monitored and managed consistent with the MHCP Management and Monitoring
Plan (Volume 3) and coverage for this species to the City does not begin until documentation that
provides these assurances is provided to the Service and Department, the plan will detect and
minimize any negative impacts that are affecting California Orcutt grass. The avoidance,
minimization, and/or mitigation measures included in the MHCP Subregional Plan and City’s
Subarea Plan will reduce any impacts that may occur to this species. Additionally, this species
will benefit from the habitat that the City’s Subarea Plan will preserve in perpetuity. This
Preserve will be adaptively managed, per the measures included in the MHCP Subregional Plan
and City’s Subarea Plan, which will further reduce the indirect effects and benefit the species.
After reviewing the current status of this species, the environmental baseline for the action area,
the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan and City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Pinus torreyana ssp. torreyana (Torrey pine)
- 325
Status of’the Species
Listing Status
Torrey pine is not a state or federal listed species. The California Native Plant Society has placed
this species on list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 3-2-3, and a
California Natural Diversity Data Bank ranking of G2S2.1.
Species Description
Pinus torreyana ssp. torreyana is a member of the Pinaceae (pine) family. P. turreyana ssp.
torreyana is a medium sized tree (<35 meters) with mature bark containing red-brown plates
between irregular furrows. A mature crown is usually open and rounded, supported by numerous
large branches. Needles are arranged in 5 per bundle (15-26 centimeters). The seed cone usually
opens the third season and is able to persist up to fifteen years.
There are two recognized subspecies of Torrey pine, (1) the mainland Torrey pine (Pinus
turreyana ssp. turreyana), which occurs in and near the Torrey Pines State Reserve (TPSR) and,
(2) Santa Rosa Island Torrey pine (Pinus torreyana ssp. insularis), which occurs only on Santa
Rosa Island off the coast of southern California, 175 miles (280 kilometers) northwest of the
mainland population (Esser 1993, Hickman 1996).
Distribution
Torrey pine has one of the most limited geographical ranges in the Pinus genus. Its natural
distribution consists of two disjunct populations: (1) on Santa Rosa Island and (2) on the coast
between San Diego and Del Mar (Biondi et al. 1997). The majority of naturally occurring Torrey
Pine trees on the mainland are protected and managed by TPSR. Healthy populations occur at
both the southern and northern extensions of the Torrey Pines preserve. Vigorous stands are
found north into Crest Canyon in Del Mar. This pine is widely planted in the region and abroad
(e.g., Kenya, New Zealand, etc. [Munz 19741) as an ornamental. Occasionally, planted stands
will generate seedlings such as on the northwestern slope of Carmel Mountain and near Oak
Crest Park in Encinitas. Smaller stands and/or individuals occur in Carlsbad, Encinitas, Del Mar,
Cannel Mountain, and the San Dieguito River Valley.
Habitat Afinity
Torrey pine typically occurs in Torrey pine forest or as inclusions in southern maritime chaparral.
It survives in the closed coniferous forests where fog often creates a much more mesic climate
(Reiser 1996). Local fogs play a very important role in the survival of this species. Loamy
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
alluvial soil is its primary soil make-up.
Life History
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Torrey pine is a wind-pollinated coniferous tree. This taxon may be self-fertile (Ledig 1987) and
apparently possesses extremely low genetic variability (Ledig 1987). Based on its low genetic
variability, it has been suggested that this species could be managed in greatly reduced
populations without seriously damaging its reproductive capacity from a genetic perspective
(Ledig 1987). Small populations would, however, be more susceptible to extirpation from a
variety of factors. Torrey pine is a fire-adapted species for which the frequency and intensity of
fire may be critical for regeneration (Barry 1988).
It regenerates sexually and will not reproduce vegetatively (Ledig 1987, Esser 1993). Torrey
pines begin to produce seed when they are 12 to 18 years old. Cones are pollinated from January
to March and reach maturity in the summer, two and a half years later (McMaster 1980). Cone
opening initiates when seeds are mature. Seed dispersal begins in September after cone-ripening
(Krugman and Jenkinson 1974;Krochmal and Krochmal 1982). Because the Torrey pine seed is
nearly wingless, wind dispersal is negligible (Esser 1993). Birds such as scrub jays aid in seed
dissemination (Ledig and Conkle 1983).
Torrey pines exhibit delayed seed dispersal, a pattern of seed release intermediate between open-
and closed-cone species. In the Torrey Pine State Reserve, Torrey pine cones begin to open
when seeds are mature, but seed fall continues for up to 13 years after cone maturity. McMaster
and Zedler (198 1) found that over 76 percent of available seeds were in cones one or more years
after seed maturity. Seed release accelerates through the fourth year when cones retain 22
percent of seeds, and then levels off or slowly declines (McMaster and Zedler 1981). Over 15
percent of the original seed is retained 11 years following cone maturity (McMaster 1980). At
age 14, cones are mostly open but still retain about 10 percent of seeds (Esser 1993, Hickman
1996).
Seed viability decreases with cone age, but seeds at least partially exposed for 10 years remain
viable (McMaster and Zedler 198 1). Seedling mortality is largely a function of water stress and
is highest in July and August (Esser 1993). Seedling establishment increases with disturbance
such as fire (Esser 1993). Predispersal loss of seed is high in Torrey pines (Esser 1993). Before
dispersal, 6.8 percent of seed is lost to arthropod seed predators within the cone and 4.6 percent
of the seed has already germinated (Esser 1993). Germination of seed in the cone is unique to
Torrey pins in the genus Pinus (McMaster 1980, McMaster and Zedler 1981).
Population Trend
The mainland population of Torrey pines was estimated at 7,000 trees in the 1960s and 1970s
(Critchfield and Elbert 1966, Elbert 1975).
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
In 1988, a bark beetle (Zpspuruconfusus) infestation occurred at TPSR. By 1990, 12 percent of
the adult trees had been killed (Esser 1993). In 1991, the U.S. Forest Service utilized synthetic
pheromines to lure Ips beetles into traps placed on trees (Berson 1992). Only one additional tree
was attacked after the trapping began (Berson 1992).
327 -
Threats
The primary threats to this species are development and insect infestations (the attacks by the
five-spined bark beetle at Torrey Pines State Reserve have apparently been contained by
biological controls and the end of a long drought period (Skinner and Pavlik 1994; Ledig 1996).
The Torrey pine possesses extremely low genetic variability (Ledig 1987), and its seeds are
heavy and nearly wingless, so dispersal is limited (Ledig 1996).
Environmental Baseline
In the MHCP, the majority of point locations (25 of 27) occur in Encinitas. Some of the trees
mapped in Encinitas have been planted. The other two point locations occur in Carlsbad. Within
the MHCP, no major populations or critical locations have been identified for this species. None
of the species points occur in Torrey pine forest habitat, in fact there are no Torrey pine forest
habitat within the MHCP planning area. Rather, the species points occur in southern maritime
chaparral. There are 968 acres of southern maritime chaparral in the MHCP planning area.
Of the two populations in the City, one of these points occurs south of Palomar Airport Road and
is isolated from other populations of this species. This population is at the northern terminus of
this species’ range. The second population is located on the western slope of Green Valley
within a large block of preserved native habitat. This point is part of a sizable population of
Torrey pines that extends into Encinitas. Torrey pine is a species with relatively low genetic
diversity. Individual trees on the periphery of the range may exhibit genetic differences, which
could help the species withstand a disease or infestation. For this reason the Torrey pine
population south of Palomar Airport Road would be significant to the species as a whole, if it
contains unique genetic information. In contrast, if the Torrey pine population in central
Carlsbad was planted it may not have the same importance to the species as a natural population.
A greater amount of research is necessary to determine the value of this point location.
Effects of the Action
Direct Efsects
The MCHP Subregional plan requires the following conditions be met for a city to receive
coverage for this species:
1. Fire management plans must be implemented for all conserved populations to protect
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 328 -
them from frequent or high-intensity fires and fire suppression activities. If determined
necessary to maintain the population, develop fire management guidelines within
conserved areas that limit fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
Direct impacts to Torrey pines will occur as a result of the MHCP Subregional Plan in the City of
Encinitas and Carlsbad, however, the extent of the impacts is expected to be low. The majority
of points (65 percent) are within the FPA and will be conserved at 100 percent in hardline areas
and at the FPA percentage (or mitigation ratio) in softline areas. No conservation will occur
outside of the FPA for this species. In addition to point localities, an estimated 748 acres (77
percent) of potentially suitable habitat will be conserved as a result of the existing preserve
design and preserve policies. More specifically, the City of Encinitas will impact 8 of 25 point
localities (33 percent). The MHCP Subregional Plan identifies the City of Carlsbad as impacting
one of two point localities (50 percent) since only one of the point localities is in the FPA,
however, the Carlsbad subarea plan specifically states that all individuals identified in the
Carlsbad plan will be conserved.
In addition, since the point localities are outside of areas that are currently being managed and
monitored for biological resources, the City of Carlsbad cannot commit to funding such
management and monitoring activities necessary at this time. Thus, the City will not receive
coverage for this species until they have the ability to ensure the appropriate level of management
and monitoring, as described in the MHCP Volume 3 and the OSMP, for these species will occur
in perpetuity associated with the permit. Thus, development that would adversely affect this
species could not be permitted under Carlsbad’s HMP until such coverage is received by the
City. The process for initiating coverage for species in Table 3 is the same as for species in
Table 2 and requires the City to document in writing that the necessary conditions of coverage
will be met with written concurrence from the Wildlife Agencies.
Indirect Efsects
The conserved Torrey pine populations are on the edge of preserved habitat. These populations
will be susceptible to invasion by exotic plants and increased traffic (wallung, domestic animals,
bilung). These edge effects will not likely impact adult trees, however, they may effect the
establishment of seedlings. The degree to which suitable habitat is fragmented after the
implementation of the plan will restrict the ability of Torrey pine to expand its range in the
MHCP planning area. These indirect impacts would be avoided and minimized by monitoring
and management of this species according to MHCP standards. However, the City would not be
able to initially fund or gain access for management and monitoring for any of the known
populations in the City until a regional funding source, or some other additional funds, are
available. Because of this, coverage for this species is not being proposed until the City of
Carlsbad can document they have access and the funds available to manage and monitor this
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
species as described in the MHCP Volume 3 and the OSMP.
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Conclusion
We have concluded that the MHCP Subregional Plan will directly impact Torrey pines in the
City of Encinitas and Carlsbad by habitat loss from development. However, the City’s Subarea
Plan commits to preserving both locations of Torrey Pine. In addition, the MHCP Subregional
Plan assures that all remaining populations of Torrey pine will be monitored and managed
consistent with the MHCP Management and Monitoring Plan (Volume 3). Coverage for this
species to the City does not begin until the City can provide documentation to the Service and
Department that adequate access and funding is available. The avoidance, minimization, and/or
mitigation measures included in the MHCP Subregional Plan and City’s Subarea Plan will
reduce any impacts that may occur to this species. This species will also benefit from the habitat
that the MHCP Subregional Plan ill preserve in perpetuity. This Preserve will be adaptively
managed, per the measures included in the MHCP Subregional Plan and the City’s Subarea Plan
which will further reduce the indirect effects and benefit the species. After reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan and the City’s Subarea Plan are not likely to jeopardize the continued existence
or recovery of this species.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Streptocephalus woottoni (Riverside fairy shrimp)
Status of the Species
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Listing Status
The Riverside fairy shrimp was listed as endangered on August 3, 1993 (58 FR 41391). A vernal
pool recovery plan, which included Riverside fairy shrimp, was published in September 1998
(U.S. Fish and Wildlife Service 1998e). Critical habitat was designated for the species on May
30, 2001 (66 Federal Register 29384); however, this designation was vacated on October 30,
2002, by order of the Federal District Court for the District of Columbia. Critical habitat was re-
proposed on April 27,2004 (69 FR 23024).
Species Description
Streptocephalus woottoni is a small freshwater crustacean in the family Streptocephalidae, of the
order Anostraca. The species was first collected in 1979 by Dr. Clyde Erickson and formally
described as a new species in 1990 (Eng et al. 1990). Mature males are between 13 and 25
millimeters (0.5 to 1.0 in) long. The cercopods (structures that enhance the rudder-like function
of the abdomen) are separate with plumose setae (feathery bristles) along the borders. Mature
females are between about 13 and 22 millimeters (0.5 to 0.87 in) in length. The brood pouch
extends to the seventh, eighth, or ninth abdominal segment. The cercopods of females are the
same as in males. The species most taxonomically similar to S. woottoni is S. seali (Eng et al.
1990). However, in S. woottoni, both the male and the female have the red color of the
cercopods covering the ninth and 30 to 40 percent of the eighth abdominal segments (Eng et al.
1990). No red extends onto the abdominal segments in living S. seali of either sex (Eng et al.
1990). A full description of identifying characteristics for this species is given by Eng et al.
(1990).
Distribution
The Riverside fairy shrimp is believed to have the most restricted distribution of an endemic
California fairy shrimp (Eng et al. 1990, Simovich and Fugate 1992). The northern distribution
limit for the Riverside fairy shrimp is Cruzan Mesa, Los Angeles County and the former
Carlsberg Ranch, Ventura County (U.S. Fish and Wildlife Service 2000b). In Baja California,
Mexico it has been documented at two locations: Valle de Las Palmas, south of Tecate, and
Bajamar, north of Ensenada (Brown et al. 1993). With the exception of the Riverside
populations, all populations are within 15 kilometers of the coast over a north-south distance of
about 140 kilometers (Eriksen and Belk 1999). All known populations lie between 30 and 415
meters in elevation. In San Diego County it is known to occur at Marine Corps Base Camp
Pendleton, City of Carlsbad, one complex at Marine Corps Air Station Miramar, and on Otay
Mesa.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 33 1
Hub itat Afin it ies
Riverside fairy shrimp are restricted to deep (greater than 25 cm in depth) seasonal vernal pools,
vernal pool-like ephemeral ponds, and stock ponds (Eng et al. 1990, U.S. Fish and Wildlife
Service 1993b). They prefer warm-water pools that have low to moderate dissolved solids
(Eriksen and Belk 1999). Pools are generally open and unvegetated with turbid water conditions
and low total dissolved solids, alkalinity, and chloride levels, as evidenced by approximately
neutral pH values (Eng et al. 1990). All known habitat lies within annual grasslands, which may
be interspersed through chaparral or coastal sage scrub vegetation.
Life History
Riverside fairy shrimp are non-selective particle-feeding filter-feeders, or omnivores. Detritus,
bacteria, algal cells, and other items between 0.3 to 100 microns may be filtered and ingested
(Eriksen and Belk 1999). Females produce between 17 and 427 cysts over their lifetime
(Simovich and Hathaway 1997), Presumably because of the ephemeral and unpredictable nature
of the pool resource, few of the available cysts hatch at a time (Eriksen and Belk 1999). Cysts
may hatch when water temperature is at 10" C but develop slowly below 15" C (Eriksen and Belk
1999). Hathoway and Simovich (1996) found that Riverside fairy shrimp hatched in 7 to 12 days
when water temperature was between 10" and 20" C and maturity was noted between 48 to 56
days. The eggs are either dropped to the pool bottom or remain in the brood sac until the female
dies and sinks (U.S. Fish and Wildlife Service 2000b). Eggs may persist in the substrate for
several years. When the pools refill in the same or subsequent rainy seasons, some but not all of
the eggs may hatch (U.S. Fish and Wildlife Service 2000b). Fairy shrimp may be eaten by a wide
variety of species, including beetles, dragonfly larvae, and other arthropods, frog, salamander,
and toad tadpoles, shorebirds, ducks, and even other fairy shrimp.
Population Trends
Many populations of Riverside fairy shrimp have likely been extirpated or have experienced
drastic declines due to the substantial loss of habitat in southern California. The majority of the
vernal pools within the range of the Riverside fairy shrimp were lost prior to 1990 (U.S. Fish and
Wildlife Service 1998b). Substantial losses have occurred in the Otay Mesa area, where over 40
percent of the vernal pools were destroyed between 1979 and 1990. Similar to San Diego
County, vernal pool habitat was once extensive on the coastal plain of Los Angeles and Orange
counties. Unfortunately, there has been a near total loss of vernal pool habitat in these areas
(Keeler-Wolf et al. 1998). Significant losses of vernal pools supporting this species have also
occurred in Riverside County (U.S. Fish and Wildlife Service 2000b).
Threats
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The Riverside fairy shrimp is especially vulnerable to alteration in hydrology, thus the protection
of watersbed function is critical to its survival. Riverside fairy shrimp are also threatened by
urban and agricultural development, modified hydrology due to adjacent road construction, and
illegal trash dumping. Unpredictable natural events such as drought or fire may extirpate the
Riverside fairy shrimp due to its fragmented and restricted range. They are also vulnerable to
contaminants in runoff waters and watershed quality. Low levels of genetic variability may
affect the species’ potential for long term viability (U.S. Fish and Wildlife Service 1993b). With
the long distance isolation between the few remaining pools, gene flow is greatly if not
completely reduced.
332 -
Critical Habitat
As stated above, critical habitat was re-proposed on April 27,2004 for Riverside fairy shrimp.
The proposed rule identified the following primary constituent elements determined essential to
the conservation of Riverside fairy shrimp: 1) Small to large pools or pool complexes that have
the appropriate temperature, water chemistry, and length of time of inundation with water
necessary for Riverside fairy shrimp incubation and reproduction, as well as dry periods
necessary to provide the conditions to maintain a dormant and viable cyst bank. Specifically, the
conditions necessary to allow for successful reproduction of Riverside fairy shrimp fall within
the following ranges: (a) Moderate to deep depths ranging from 10 inches to 5 to 10 feet; (b)
Ponding inundation that lasts for a minimum length of 2 months and a maximum length of 5 to 8
months, i.e., a sufficient wet period in winter and spring months to allow the Riverside fairy
shrimp to hatch, mature, and reproduce, followed by a dry period prior to the next winter and
spring rains; (c) Water temperature that falls within the range of 50 and 77 degrees Fahrenheit;
and d. Water chemistry with low total dissolved solids and alkalinity (means of 77 and 65 parts
per million, respectively), corroborated by pH within a range of 6.4 to 7.1; 2) Associated
watersheds that provide water to fill the pools in the winter and spring months. The size of the
associated watershed varies greatly and cannot be generalized and has been assessed on a case-
by-case basis. Factors that affect the size of the watershed include surface and underground
hydrology, the topography of the area surrounding the pool or pools, the vegetative coverage, and
the soil substrate in the area. Watershed sizes designated vary from a few acres to greater than
100 acres; and 3) Any soil type with a clay component andor an impermeable surface or
subsurface layer known to support vernal pool habitat. The matrix of vernal pools/ephemeral
wetlands, the associated watershed, upland habitats, and underlying soil substrates form
hydrological and ecologically functional units. These features and the lands that they represent
are essential to the conservation of the Riverside fairy shrimp. All lands identified as essential
and proposed as critical habitat contain one or more of the primary constituent elements for the
Riverside fairy shrimp.
Environmental Baseline
Riverside fairy shrimp is only reported from one vernal pool complex in the MHCP at the
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 333
Poinsettia Lane Commuter Rail Station in Carlsbad. The vernal pool complex at this location
occurs in a narrow band running north to south along the train tracks. Both the train tracks and
adjacent hevelopment have altered the hydrology of this area. The pools have exotic weeds on
their margins and face the threat of run-off from an adjacent development. The current status of
Riverside fairy shrimp at this location is unknown. The pools at Poinsettia Lane have been
degraded by agriculture and construction of the train station, however, they continue to function
as vernal pool habitat. The Poinsettia Lane pools and their watersheds occur on both North
County Transit District (NCTD) land and private property associated with the Water’s End
housing development project. The Service formally consulted under section 7 of the Act (1-6-
94-F-9) with the U.S. Army Corps of Engineers on the adverse affects associated with the train
station on this species (U.S. Fish and Wildlife Service, 1994b). In response to this consultation,
NCTD agreed to grant a conservation easement over all the pools on their property to the
California Department of Fish and Game and provide a management plan with an endowment for
the management of the pools. These obligations remain outstanding, however, active progress is
being made. The Water’s End development has agreed to avoid impacts to the vernal pool
watersheds and will provide an easement over the pool watersheds on their property to the City
with California Department of Fish and Game and the US Fish and Wildlife Service as third
party beneficiary. In addition, they are providmg $100,000 of funds to the City for an
endowment to manage and monitor the Poinsettia Lane pool watersheds. The California
Department of Fish and Game and the City of Carlsbad will ensure that these pools and their
watersheds are managed to MHCP standards.
-
There are two other areas in the Carlsbad subarea that support vernal pool habitat, however,
Riverside fairy shrimp have not been reported from these other vernal pool complexes. Riverside
fairy shrimp have also not been reported from San Marcos vernal pools.
Critical habitat for the Riverside fairy shrimp has been re-proposed to include 143 acres in the
MHCP planning area, 8 acres of which are within the FPA. All 8 acres are within the City at the
Poinsettia Lane Commuter Rail Station vernal pool complex. Some of the difference in acreage
between 143 acres and 8 acres is due to a course mapping scale for the critical habitat units.
However, some of the acreage is because the City’s FPA does not completely cover all the vernal
pools and their watersheds at the Poinsettia Lane Commuter Rail Station.
Effects of Action
Direct Effects
No direct effects to the Riverside fairy shrimp are expected from the implementation of the
MHCP Subregional and City’s Subarea Plan because all of the pools that are known to support
Riverside fairy shrimp are 100 percent conserved. In addition, the MHCP no net loss policy for
wetlands includes vernal pool habitat. Therefore, all vernal pools within the MHCP are expected
to be 100 percent conserved. The MHCP also treats Riverside fairy shrimp as a narrow endemic
333
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 334 -
species. Thus, if Riverside fairy shrimp are discovered in other areas in the MHCP planning
area, inclpding the City of Carlsbad, they will be conserved accordingly. More importantly, the
following conditions must be met in order for a City to receive coverage for this species:
1.
2.
3.
4.
5.
All vernal pools and their watersheds within the MHCP study area must be 100 percent
conserved, regardless of occupancy by this species and regardless of location inside or
outside of the FPA, unless doing so would remove all economic uses of a property. In the
event that no project alternative is feasible that avoids all impacts on a particular property,
the impacts must be minimized and mitigated to achieve no net loss of biological
functions and values through strict adherence to the Wetland Avoidance and Mitigation
Criteria (Section 3.6.1 of MHCP Volume 1)’ Standard Best Management Practices
(Appendix B), and Revegetation Guidelines (Appendix C).
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist possessing a Section 10(a)l(A) research permit for this
species must survey all areas containing pools, using approved Riverside fairy shrimp
survey protocol. Surveys shall be conducted when impacts could occur as a result of
direct or indirect impacts by placement of a project in or adjacent to suitable habitat.
Suitable habitat includes vernal pools as well as any other pools (natural or unnatural)
that have potential to support fairy shrimp based on their physical, chemical, and
biological attributes.
All known or newly discovered populations of Riverside fairy shrimp and their habitat,
including pool watersheds (surface and subsurface hydrology that support pool formation)
and adequate adjacent upland habitat to allow for ecosystem processes to maintain this
species, shall be preserved consistent with the Critical Population Policy (Appendix D)
and managed as part of the preserve system.
Management Plans must prohibit and actively exclude any activities that could degrade
vernal pool habitat, including but not limited to threats identified in MHCP Volume 2 for
this species.
All species-specific monitoring identified in the MHCP Volume 3 shall be implemented.
No direct impacts will occur to the only known population of Riverside fairy shrimp at the
Poinsettia Commuter Rail Station vernal pools from either the MHCP Subregional Plan or the
City’s Subarea Plan since it occurs in a 100 percent preserve area. In addition, applying the
above conditions throughout the MHCP planning area will result in all new species points
identified being preserved since the plan requires all pools and their watersheds within the
MHCP planning area to be 100 percent conserved, regardless of occupancy by this species and
regardless of location inside or outside the PA, unless doing so would remove all economic use
of a property.
Once again, the City’s subarea plan will not result in any direct impacts to the only known
population of Riverside fairy shrimp at the Poinsettia Commuter Rail Station vernal pools.
However, the City’s subarea plan will result in direct impacts to one vernal pool watershed on the
334
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 335 -
Hieatt property. In addition, the City of Carlsbad will not receive coverage for this species until
documentation is provided that assures the above conditions (excluding the Hieatt property from
the water‘shed protection condition), including management and monitoring of this species in
perpetuity throughout the City and at the Poinsettia Lane Commuter Rail Station, according to
MHCP Volume 3 standards, can be met among the signatories to the IA (City, Service, and/or
Department). Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 3 is the same as for species in Table 2 and requires the City to
document in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
No direct impacts will occur to the constituent elements for Riverside fairy shrimp proposed
critical habitat from the MHCP Subregional Plan or the City’s Subarea Plan. All of the vernal
pools at the Poinsettia Commuter Rail Station will be 100 percent conserved.
Indirect Efsects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station will increase the amount of foot and bicycle traffic in the area.
This increase in activity could lead to trampling of sensitive plants and the introduction of
invasive exotic plants. The pools will be most vulnerable to these impacts during the wet winter
and spring months. As the density of residential housing around this vernal pool complex
increases, these pools will become isolated from other vernal pool complexes and the existing
matrix of undeveloped habitat in Carlsbad.
In addition, the run-off from adjacent residential development may indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year-
round fresh water marsh, whereas too little water will not provide the Riverside fairy shrimp with
the ponding duration needed to successfully reproduce. Both pollutants and sediment load will
likely impact the success of these pools and, therefore, the water quality will need to be
monitored. However, the MHCP and the City’s HMP would ensure management and monitoring
of all the pools in the MHCP and prohibit and exclude any activities that could degrade vernal
pool habitat.
The MHCP Subregional Plan and City’s Subarea Plan could indirectly adversely affect the
constituent elements of Riverside fairy shrimp proposed critical habitat. The indirect effects are
the same as described above. More specifically, development will occur in the general area that
could adversely affect the hydrology of the vernal pools at this site. The conditions of coverage
for this species and the management and monitoring required for this species will address this
issue and ensure impacts are minimized.
Conclusion
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
We have concluded that no direct impacts will occur to the only known population of Riverside
fairy shrimp at the Poinsettia Commuter Rail Station vernal pools from either the MHCP
Subregional Plan or the City’s Subarea Plan. The MHCP Subregional Plan also protects any new
populations of Riverside fairy shrimp because all vernal pools and their watersheds within
MHCP must be 100 percent conserved regardless of occupancy by this species. In addition, since
the plans provides assurances that the known populations and any new populations of Riverside
fairy shrimp will be monitored and managed consistent with the MHCP Management and
Monitoring Plan (Volume 3) and coverage for this species to the City does not begin until
documentation that provides these assurances is provided to the Service and Department, the plan
will detect and minimize any negative impacts that are affecting Riverside fairy shrimp. The
avoidance, minimization, and/or mitigation measures included in the h4HCP Subregional Plan
and City’s Subarea Plan will reduce any impacts that may occur to this species. After reviewing
the current status of this species, the environmental baseline for the action area, the effects of the
proposed action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan and City’s Subarea Plan are not likely to jeopardize the continued existence or
recovery of this species.
336 -
We anticipate the MHCP Subregional Plan and the City’s Subarea Plan will adversely affect
Riverside fairy shrimp critical habitat. However, only indirect effects are expected and critical
habitat would remain functional and ensure conservation of the species for the following reasons:
1) most of the critical habitat area occurs within the 100 percent preserved area of the Poinsettia
Commuter Rail Station vernal pool complex; 2) the MHCP Subregional Plan requires all vernal
pools and their watersheds to e 100 percent conserved regardless of their occupancy with
Riverside fairy shrimp and regardless of location inside or outside the PA; 3) the MHCP
Subregional Plan requires all vernal pools in the FPA to be managed and monitored to restrict
activities that could degrade Riverside fairy shrimp habitat; and 4) the MHCP Subregional Plan
requires all known or newly discovered populations of Riverside fairy shrimp and their habitat to
be preserved consistent with the critical locations policy of MHCP. Thus, after reviewing the
status, environmental baseline for the action area, and the effects of the proposed action and the
cumulative effects on Riverside fairy shrimp critical habitat, it is the Service’s biological opinion
that the Subregional MHCP Plan is not likely to adversely modify critical habitat proposed for
Riverside fairy shrimp.
336
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 337
Amount or Extent of Take
The Service anticipates that an unknown number of Riverside fairy shrimp could be taken as a
result of the City’s subarea plan. The incidental take is expected to be in the form of impacts to
one vernal pool watershed which could harm or injure Riverside fairy shrimp through changes in
pool hydrology. The amount of incidental take is expected to be low because the wetland
protection standards apply to vernal pools, Riverside fairy shrimp are treated as narrow endemics,
and MHCP Subregional Plan standards require all vernal pools and their watersheds be 100
percent conserved. This level of anticipated take is not likely jeopardize the continued existence
or recovery of the species.
337
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Branchinecta sandiegonensis (San Diego fairy shrimp)
- 338
Status of the SDecies
Listing Status
The San Diego fairy shrimp was federally listed as endangered on February 3, 1997 (62 FR
4925). A vernal pool recovery plan which included San Diego fairy shrimp was published in
September 1998 (U.S. Fish and Wildlife Service 1998e).
Species Description
Branchinecta sandiegonensis, is a small aquatic crustacean (Order: Anostraca) restricted to
vernal pools. B. sandiegonensis was originally described by Fugate (1993) from samples
collected on Del Mar Mesa, San Diego County. Mature individuals lack a carapace (hard outer
covering of the head and thorax) and have a delicate elongate body, large stalked compound eyes,
and 11 pairs of swimming legs (U.S. Fish and Wildlife Service 2000b). Adult male San Diego
fairy shrimp range in size from 9 to 16 millimeters (0.35 to 0.63 in); adult females are 8 to 14
millimeters (0.3 1 to 0.55 in) long. The second pair of antennae in males are greatly enlarged and
specialized for clasping the females during copulation, while the second pair of antennae in the
females are cylindrical and elongate. Refer to Fugate (1993) for a detailed description of the
identifying characteristics of B. sandiegonensis.
Distribution
The San Diego fairy shrimp occurs in vernal pools from Marine Corps Base Camp Pendleton,
inland to Ramona and south through Del Mar Mesa, Proctor Valley, and Otay Mesa, San Diego
County, California. The species has recently been documented in Orange County in the Fairview
Park vernal pools and at Saddleback Meadows (U.S. Fish and Wildlife Service 1997~). In Baja
California, it has been recorded at two localities (Valle de Palmas, south of Tecate and Baja Mar,
north of Ensenada) and a single isolated female was reported from vernal pools in Isla Vista,
Santa Barbara County, California (U.S. Fish and Wildlife Service 1995d).
Habitat Afinities
San Diego fairy shrimp tend to inhabit shallow, small vernal pools and vernal pool-like
depressions (e.g., ruts in dirt roads) with water temperatures of 10-26" C. They are ecologically
dependent on seasonal fluctuations in their habitat, such as absence or presence of water during
specific times of the year, duration of inundation, and other environmental factors that likely
include specific salinity, conductivity, dissolved solids, and pH levels. Gonzalez et al. (1996)
found water chemistry as an important factor in determining the distribution of the San Diego
fairy shrimp.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Critical Habitat
- 339
Critical Gabitat was designated for this species on October 23,2000 (65 FR: 63438). Critical
habitat was then remanded, but not vacated on June 11,2002. Critical habitat was proposed on
April 22,2003 (68 FR 19888). Both the October 23,2000, final designation and the April 22,
2003, proposal identified the following primary constituent elements for the vernal pool basins
and associated watersheds to include, but not be limited to: 1) small to large vernal pools with
shallow to moderate depths that hold water for sufficient lengths of time necessary for San Diego
fairy shrimp incubation and reproduction, but not necessarily every year; 2) associated
watershed(s) and hydrology for vernal pool basins and their related vernal pool complexes; 3)
ephemeral depressional wetlands, flat or gently sloping topography, and any soil type with a clay
component and/or an impermeable surface or subsurface layer known to support vernal pool
habitat. The associated watersheds were stated as essential in maintaining the hydrology of
vernal pools necessary to support San Diego fairy shrimp.
Life History
San Diego fairy shrimp are non-selective particle filter-feeders, or omnivores. Detritus, bacteria,
algal cells, and other items between 0.3 to 100 microns may be filtered and ingested (Eriksen and
Belk 1999). Adult fairy shrimp are usually observed from January to March; however, in years
with early or late rainfall, the hatching period may be extended (U.S. Fish and Wildlife Service
2000b). This species hatches in 3 to 8 days and matures in about 7 to 17 days depending on
water temperature (Hathaway and Simovich 1996). San Diego fairy shrimp may only persist for
about 4 to 6 weeks after hatching (Hathaway and Simovich 1996). The eggs are either dropped
to the pool bottom or remain in the brood sac until the female dies and sinks (U.S. Fish and
Wildlife Service 2000b). Eggs may persist in the substrate for several years. When the pools
refill in the same or subsequent rainy seasons, some but not all of the eggs may hatch (U.S. Fish
and Wildlife Service 2000b). Fairy shrimp may be eaten by a wide variety of species, including
beetles, dragonfly larvae, and other arthropods, frog, salamander, and toad tadpoles, shorebirds,
ducks, and even other fairy shrimp.
Population Trend
The San Diego fairy shrimp is known to occur in most of the vernal pool complexes in coastal
San Diego County (U.S. Fish and Wildlife Service 1998b). Many populations of San Diego fairy
shrimp have likely been extirpated or have experienced drastic declines due to the substantial
loss of habitat in southern California. The majority of the vernal pools within the range of the
San Diego fairy shrimp were lost prior to 1990 (U.S. Fish and Wildlife Service 1998b). The
greatest recent losses of vernal pool habitat in San Diego County have occurred in Mira Mesa,
Rancho Penasquitos, and Kearny Mesa, which accounted for 73 percent of all the pools destroyed
in the region from 1979 to 1986 (Keeler-Wolf et al. 1998). Other substantial losses have
occurred in the Otay Mesa area, where over 40 percent of the vernal pools were destroyed
339
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 340
between 1979 and 1990. Similar to San Diego County, vernal pool habitat was once extensive
on the coptal plain of Los Angeles and Orange counties. Unfortunately, there has been a near
total loss of vernal pool habitat in these areas (Keeler-Wolf et al. 1998).
-
Threats
The San Diego fairy shrimp is especially vulnerable to alteration in hydrology, thus the
protection of watershed function is critical to its survival. San Diego fairy shrimp are also
threatened by urban, agricultural development, modified hydrology due to adjacent road
construction, and illegal trash dumping. Unpredictable natural events such as drought or fire’may
extirpate the San Diego fairy shrimp due to its fragmented and restricted range. They are also
vulnerable to contaminants in runoff waters and watershed quality. Low levels of genetic
variability may affect the species’ potential for long term viability (U.S. Fish and Wildlife
Service 1997~).
Environmental Baseline
There are two locations where San Diego fairy shrimp are found in the MHCP planning area,
both of which are considered major populations and critical locations. One of these populations
is located in San Marcos and the other is in the City of Carlsbad at the Poinsettia Lane Commuter
Station. However, all of the populations in San Marcos are in the major amendment area. Thus,
the conditions of the MHCP for this species will not apply to these areas and adverse affects to
these areas will not be covered by the MHCP plan. However, the pools in San Marcos on the
Bent Avenue property will be conserved. A U.S. Army Corps of Engineers permit (Corps Permit
No. 200001 113-TCD) was issued to South Coast Development on December 15,2000, which
required a the long-term preservation of 4.5 acres of vernal pool watershed on the Bent Avenue
property via a recorded conservation easement over the areas to be conserved. According to
Marie Somovich, San Diego fairy shrimp were present in these pools in 1992. Their current
status is unknown. It is our understanding that the conservation easement has not yet been
recorded.
The pools at Poinsettia Lane Commuter Station are known to have had San Diego fairy shrimp,
but the current status of their occupation is unknown. These pools have been degraded by
agriculture and construction of the train station, however, they continue to function as vernal
pool habitat. The Poinsettia Lane pools and their watersheds occur on both North County Transit
District (NCTD) land and private property associated with the Water’s End housing development
project. The Service formally consulted under section 7 of the Act (1-6-94-F-9) with the U.S.
Army Corps of Engineers on the adverse affects associated with the train station on this species
(US. Fish and Wildlife Service, 1994b). In response to this consultation, NCTD agreed to grant
a conservation easement over all the pools on their property to the California Department of Fish
and Game and provide a management plan with an endowment for the management of the pools.
These obligations remain outstanding, however, active progress is being made. The Water’s End
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
development has agreed to avoid impacts to the vernal pool watersheds and will provide an
easement over the pool watersheds on their property to the City with California Department of
Fish and Game and the US Fish and Wildlife Service as third party beneficiary. In addition, they
are providing $100,000 of funds to the City for an endowment to manage and monitor the
Poinsettia Lane pool watersheds. The California Department of Fish and Game and the City of
Carlsbad will ensure that these pools and their watersheds are managed to MHCP standards.
34 1 -
There are two other vernal pool complexes in Carlsbad that may provide suitable habitat for San
Diego fairy shrimp, but the species is currently unreported from these two areas.
A total of 335 acres of critical habitat was designated for San Diego fairy shrimp within the
MHCP. Of this, 135 acres are within the City of Carlsbad and the remaining 200 acres are within
the City of San Marcos. None of the existing critical habitat in the City of San Marcos is within
the FPA for MHCP and as a result are not included in this analysis.
Critical habitat was proposed on only 119 acres within the MHCP; a majority of which is in the
City of San Marcos. However, once again, none of the proposed critical habitat in the City of
San Marcos is within the FPA for MHCP and as a result are not included in this analysis. In
Carlsbad, 8 acres of critical habitat are within the FPA at the Poinsettia Train Station vernal pool
complex. Some of the difference in acreage between the critical habitat and FPA are due to a
course mapping scale used for critical habitat. There is also a 11 acre spillover from pools on
Marine Corps Base Camp Pendleton. However, some of the difference in acreage is because not
all of the Poinsettia Train Station vernal pool watershed is within the FPA.
The difference in 335 acres of designated critical habitat and 119 acres of proposed critical
habitat within the MHCP planning area is mostly due to the differences in mapping scales used to
designated critical habitat and those used to propose critical habitat. The original designation
used a 250 meter grid cell, where the recently proposed critical habitat used only a 100 meter
grid. However, one area was omitted from proposed critical habitat within the City of Carlsbad
that is currently designated critical habitat. This is the Hieatt property. Thus, our consultation on
designated critical habitat is sufficient for our analysis of effects to proposed critical habitat since
biologically the only difference is that there one less vernal pool complex within the proposed
critical habitat for San Diego fairy shrimp.
Effects of the Action
Direct Effects
No direct effects to the San Diego fairy shrimp are expected from the implementation of the
MHCP Subregional and City’s Subarea Plan because all of the pools that are known to support
San Diego fairy shrimp are either 100 percent conserved or are outside of the scope of the plans
since they are in a major amendment area for the City of San Marcos. In addition, the MHCP no
34 I
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
net loss policy for wetlands includes vernal pool habitat. Therefore, all vernal pools within the
MHCP qe expected to be 100 percent conserved. The MHCP also treats San Diego fairy shrimp
as a narrow endemic species. Thus, if San Diego fairy shrimp are discovered in other areas in the
MHCP planning area, including the City of Carlsbad, they will be conserved accordingly. More
importantly, the following conditions must be met in order for a City to receive coverage for this
species:
1.
342 -
All vernal pools and their watersheds within the MHCP study area must be 100 percent
conserved, regardless of occupancy by this species and regardless of location inside or
outside of the FPA, unless doing so would remove all economic uses of a property. In the
event that no project alternative is feasible that avoids all impacts on a particular property,
the impacts must be minimized and mitigated to achieve no net loss of biological
functions and values through strict adherence to the Wetland Avoidance and Mitigation
Criteria (Section 3.6.1 of MHCP Volume l), Standard Best Management Practices
(Appendix B), and Revegetation Guidelines (Appendix C).
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist possessing a Section lO(a)l(A) research permit for this
species must survey all areas containing pools, using approved San Diego fairy shrimp
survey protocol. Surveys shall be conducted when impacts could occur as a result of
direct or indirect impacts by placement of a project in or adjacent to suitable habitat.
Suitable habitat includes vernal pools as well as any other pools (natural or unnatural)
that have potential to support fairy shrimp based on their physical, chemical, and
biological attributes.
All known or newly discovered populations of San Diego fairy shrimp and their habitat,
including pool watersheds (surface and subsurface hydrology that support pool formation)
and adequate adjacent upland habitat to allow for ecosystem processes to maintain this
species, shall be preserved consistent with the Critical Population Policy (Appendix D)
and managed as part of the preserve system.
Management Plans must prohibit and actively exclude any activities that could degrade
vernal pool habitat including, but not limited to, threats identified in MHCP Volume 2 for
this species.
All species-specific monitoring identified in the MHCP Volume 3 shall be implemented.
2.
3.
4.
5.
No direct impacts will occur to San Diego fairy shrimp due to the MHCP subregional plan or the
City’s subarea plan because: 1) the population of San Diego fairy shrimp at the Poinsettia
Commuter Rail Station vernal pools occurs in a 100 percent preserve area; 2) the San Diego fairy
shrimp in the Bent Avenue pools should be 100 percent conserved due to Corps permit
conditions; and 3) the other pools with San Diego fairy shrimp within the MHCP study area are
within a major amendment area for the City of San Marcos. In addition, applying the above
conditions throughout the MHCP planning area will result in all new species points identified
being preserved since the plan requires all pools and their watersheds within the MHCP planning
area to be 100 percent conserved, regardless of occupancy by this species and regardless of
location inside or outside the FPA, unless doing so would remove all economic use of a property.
342
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 343 -
Once again, the City’s subarea plan will not result in any direct impacts to the population of San
Diego fairy shrimp at the Poinsettia Commuter Rail Station vernal pools. However, the City’s
subarea ilan will result in direct impacts to one vernal pool watershed on the Hieatt property. In
addition, the City of Carlsbad will not receive coverage for this species until documentation is
provided that assures the above conditions (excluding the Hieatt property from the watershed
protection condition), including management and monitoring of this species in perpetuity
throughout the City and at the Poinsettia Lane Commuter Rail Station, according to MHCP
Volume 3 standards, can be met among the signatories to the IA (City, Service, andor
Department). Thus, development that would adversely affect this species could not be permitted
under Carlsbad’s HMP until such coverage is received by the City. The process for initiating
coverage for species in Table 3 is the same as for species in Table 2 and requires the City to
document in writing that the necessary conditions of coverage will be met with written
concurrence from the Wildlife Agencies.
The MHCP Subregional Plan and the City’s Subarea Plan will directly impact one of the
constituent elements for designated San Diego fairy shrimp critical habitat on the Hieatt property.
These impacts include the permanent loss of a portion of one vernal pool watershed. No other
direct impacts will occur to San Diego fairy shrimp critical habitat within the MHCP planning
area and the City of Carlsbad because all of the vernal pools at the Poinsettia Commuter Rail
Station will be 100 percent conserved and any future impacts to the other pools in the City of San
Marcos will not be due to the MHCP Subregional Plan or the City’s subarea plan.
Indirect Efiects
Increased residential development near the Poinsettia Lane vernal pools and increased use of the
Poinsettia Lane Commuter Station and increased development near the Bent Avenue pools in
San Marcos will increase the amount of foot and bicycle traffic in the area. This increase in
activity could lead to trampling of sensitive plants and the introduction of invasive exotic plants.
The pools will be most vulnerable to these impacts during the wet winter and spring months. As
the density of residential housing around these vernal pool complexes increase, these pools will
become isolated from other vernal pool complexes and the existing matrix of undeveloped
habitat in the MHCP planning area.
In addition, the run-off from adjacent residential development may indirectly impact these vernal
pools. The effect of run-off needs to be closely monitored. Too much water could lead to a year-
round fresh water marsh, whereas too little water will not provide the San Diego fairy shrimp
with the ponding duration needed to successfully reproduce. Both pollutants and sediment load
will likely impact the success of these pools and, therefore, the water quality will need to be
monitored. However, the MHCP and the City’s HMP would ensure management and monitoring
of all the pools in the MHCP and prohibit and exclude any activities that could degrade vernal
pool habitat.
343
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 344 -
The MHCP Subregional Plan and City’s Subarea Plan could indirectly adversely affect the
constituent elements of San Diego fairy shrimp proposed critical habitat. The indirect effects are
the same’as described above. More specifically, development will occur in the general area that
could adversely affect the hydrology of the vernal pools at this site. The conditions of coverage
for this species and the management and monitoring required for this species will address this
issue and ensure impacts are minimized.
Conclusion
We have concluded that no direct impacts will occur to the population of San Diego fairy shrimp
at the Poinsettia Commuter Rail Station vernal pools or the Bent Avenue vernal pools from either
the MHCP Subregional Plan or the City’s Subarea Plan. The MHCP Subregional Plan does not
cover the vernal pools in San Marcos within the major amendment area. The MHCP Subregional
Plan does protect all new populations of San Diego fairy shrimp because all vernal pools and
their watersheds within MHCP must be 100 percent conserved regardless of occupancy by this
species. In addition, since the plans provide assurances that the known populations and any new
populations of San Diego fairy shrimp will be monitored and managed consistent with the
MHCP Management and Monitoring Plan (Volume 3) and coverage for this species to the City
does not begin until documentation that provides these assurances is provided to the Service and
Department, the plan will detect and minimize any negative impacts that are affecting San Diego
fairy shrimp. The avoidance, minimization, and/or mitigation measures included in the MHCP
Subregional Plan and City’s Subarea Plan will reduce any impacts that may occur to this species.
After reviewing the current status of this species, the environmental baseline for the action area,
the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan and City’s Subarea Plan are not likely to jeopardize the
continued existence or recovery of this species.
We anticipate the MHCP Subregional Plan and the City’s Subarea Plan will adversely affect
designated and proposed San Diego fairy shrimp critical habitat. Direct effects to one vernal
pool on the Hieatt property in the City of Carlsbad will occur by loss of a portion of its
watershed. However, critical habitat would remain functional and ensure conservation of the
species for the following reasons: 1) most of the critical habitat in Carlsbad occurs within the 100
percent preserved area of the Poinsettia Commuter Rail Station vernal pool complex; 2) the
MHCP Subregional Plan does not cover the vernal pools in San Marcos that are in the major
amendment area; 3) the MHCP Subregional Plan will not directly adversely affect the Bent
Avenue vernal pools in the City of San Marcos; 4) other than the Hieatt property, the MHCP
Subregional plan requires all other vernal pools and their watersheds to be 100 percent conserved
regardless of their occupancy with San Diego fairy shrimp and regardless of location inside or
outside the FPA; 5) the MHCP Subregional Plan requires all vernal pools in the FFA to be
managed and monitored to restrict activities that could degrade San Diego fairy shrimp habitat;
and 6) the MHCP Subregional Plan requires all known or newly discovered populations of San
Diego fairy shrimp and their habitat to be preserved consistent with the critical locations policy
344
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4) 345 -
of MHCP. Thus, after reviewing the status, environmental baseline for the action area, and the
effects of the proposed action and the cumulative effects on San Diego fairy shrimp critical
habitat, it‘is the Service’s biological opinion that the Subregional MHCP Plan is not likely to
adversely modify designated and proposed critical habitat for San Diego fairy shrimp.
Amount or Extent of Take
The Service anticipates that an unknown number of San Diego fairy shrimp could be taken as a
result of the City’s subarea plan. The incidental take is expected to be in the form of impacts to
one vernal pool watershed which could hm or injure San Diego fairy shrimp through changes
in pool hydrology. The amount of incidental take is expected to be low because the wetland
protection standards apply to vernal pools, San Diego fairy shrimp are treated as narrow
endemics, and MHCP Subregional Plan standards require all vernal pools and their watersheds
be 100 percent conserved. This level of anticipated take is not likely jeopardize the continued
existence or recovery of the species.
345
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) -
SPECIES-BY-SPECIES EVALUATIONS
347
SPECIES &OM TABLE 4:
The City has not committed to implementing the necessary conditions as described in MHCP
Volume 2 for the species listed in Table 4 of this biological opinion. Thus, the City has not
requested coverage for these species. As a result, the analysis of effects provided below will
mainly be in the context of the MHCP Subregional Plan. As a result, the amount or extent of
take for the animal species on this list will not estimated. However, each species will be
evaluated to ensure that the City’s lack of participation for these species would not jeopardize the
continued existence or recovery of the species.
Dudleya blochrnuniae ssp. brevifoliu (short-leaved dudleya)
Status of the Species
Listing Status
The Service proposed listing the short-leaved dudleya as threatened in 1993, however, as a result
of protection afforded this taxon under the Multiple Species Conservation Program, the Service
determined that threats to short-leaved dudleya have decreased since it was proposed for listing
and withdrew the proposal to list this species as threatened (Service 1996~). Thus, it has no
federal status, however, the State of California Department of Fish and Game listed this species
as endangered. The California Native Plant Society has placed this species on list 1B with a R-
E-D (Rarity-Endangerment-Distribution) code of 3-3-3. It is a MHCP narrow endemic species.
Species Description
Short-leaved dudleya is an herbaceous succulent perennial. It is a small sprouting perennial herb
in the stonecrop family (Crassulaceae). Short-leaved dudleya can be distinguished from
Blochman’s dudleya by its smaller (7-15 mm) spoon-shaped leaf, and from variegated dudleya by
it white, rather yellow flowers. It produces small rosette leaves from a corn. This tiny plant
resembles the small, hard concretions of its habitat.
Distribution
The entire distribution of this San Diego County endemic plant is approximately 2.5 miles wide
by 7 miles long, in the area between Del Mar and La Jolla (Moran 1950). fistorical occurrences
include Torrey Pines, the rim of La Jolla Canyon, the mesa on the south side of McGonigle
Canyon, the mesa east of Del Mar, Crest Canyon, and Camel Mountain. The species has been
extirpated from the mesa above La Jolla and Del Mar Heights Road, and some other populations
may also be extirpated. This species is not known from the MHCP planning area.
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Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4)
Ha bitat Afin ily
- 348
Short-leaved dudleya is generally found on dry, sandstone bluffs in southern maritime chaparral.
More specifically on Carlsbad gravelly loam (derived from Torrey sandstone). Known
populations are confined to the red sandstone-capped areas of the Linda Vista Terrace, a
distinctive, uncommon habitat marked by thin soils, reddish ironstone concretions, and sparse
vegetation (Moran 1950). Ashy spike moss is one of the few plants that occurs with it in these
openings.
Life History
It is insect-pollinated (e.g., bees or bee flies, Wyatt 1983), and seeds are presumably self-
dispersed. It blooms in the spring.
Population Trends
This species has experienced significant losses in San Diego County, however ,the five known
remaining populations in San Diego County are thought to be stable.
Threats
Threats to short-leaved dudleya include urbanization, edge effects, and vehicular traffic.
Although short-leaved dudleya may have some adaptation to fire, it may be adversely affected by
unnatural fire regimes (e.g., frequent fires, high-intensity fires resulting from fire suppression
policies), particularly where they result in a type conversion of native habitat and/or invasion of
habitat by nonnative weedy species. In addition, this species may be susceptible to soil surface
disturbance. Therefore, effective conservation of short-leaved dudleya would need to include a
fire management plan that protects conserved populations from frequent or high-intensity fires
and from equipment associated with fire suppression activities (e.g., vehicles). Conserved
populations would also need to be protected from trampling or other soil surface disturbance.
Environmental Baseline
There are no known localities in the MHCP database and as a result there are no major
populations or critical locations of short-leaved dudleya in the MHCP study area. Much of the
study area is beyond the known distributional limit of this species, however, there is some
potential for occurrence based on the presence of suitable habitat. The level of survey effort for
this species in the study area is considered relatively low and short-leaved dudleya can be
difficult to find when not in flower.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 349
Effects of Action
Direct Effects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. At least five self-sustaining, distinct populations' must be conserved within the species
geographic range (including 100% of extant populations and the majority of all newly
discovered, naturally occurring populations and artificially initiated populations) before
any incidental take is allowed.
The MHCP narrow endemic policy must be applied to any population of this species,
including those already known and any found in the future.
All conserved populations must be managed for genetic considerations as a
metapopulation.
A fire management plan must be implemented for all conserved populations to protect
them from frequent or high-intensity fires and fire suppression activities.
Declining populations must be enhanced and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populatios, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
As part of the project review process (e.g. CEQA) for individual projects within the
MHCP area, a qualified biologist must survey for this species in all potential habitat
areas.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
3.
4.
5.
6.
7.
There are no known occurrences of short-leaved dudleya in the MHCP planning area. However,
I The five self-sustaining populations do not necessarily need to be within the MHCP study area, but do need
to be situated within the known distributional range of this species and/or within suitable habitat (i.e., MSCP
and MHCP study areas). Self-sustaining populations are defined as those that retain genetic resources necessary
to undergo adaptive evolutionary change (Guerrant 1996). Determination of a viable or self-sustaining
population shall be assessed through long-term monitoring (e.g., 5 to 10 years) and shall include demographic
measures (e.g., the number of individuals or viable seeds in a population is stable or increasing over time) and
genetic measures (e.& changes in overall genetic diversity as measured against a baseline genetic profile)
(Primack 1996; Falk et al. 1996). Self-sustaining populations should contain a minimum of 500 individuals to
reduce the risk of extinction from intrinsic or randomevents, unless research or monitoring indicates that higher
or lower population numbers are appropriate for this species. In addition, self-sustaining populations should
occur within blocks of natural habitat that are large enough (i.e., >50 acres) to support appropriate pollinators
and buffer the conserved population from edge effects.
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Carlsbad Subarea Plan Biological and Conference Opinions (F’WS-SDG-847.4)
there is suitable habitat of which an estimated 472 acres (75 percent) of potentially suitable
habitat for this species will be conserved in the FPA (Table 4-13). This includes some larger
blocks of;ntact habitat (e.g., Green Valley, Lux Canyon). In addition, 95 or 100 percent of any
newly detected localities for this species would be conserved inside the FPA and a minimum 80
percent would be conserved outside the FPA through application of the narrow endemic policy.
Additional conservation could occur through application of the critical location policy.
3 50 -
Indirect Eflects
This plant could be indirectly impacted by the implementation of the MHCP Subregional Plan.
However, the MHCP requires the following conditions be met by a City to receive coverage for
this species: 1) Fire management plans must be implemented for all conserved populations to
promote biological goals (e.g. regeneration), while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled burns (or other fuel reduction
methods in urban areas), while limiting fire frequency and emergency access; and 2) All species-
specific monitoring and management identified in the MHCP Monitoring and Management Plan
(Volume 3) must be implemented. Thus, if this species is found within the MHCP planning area,
indirect impacts will be minimized.
Conclusion
We have concluded that the MHCP Subregional Plan will not directly impact this species since it
is currently not known to occur within the planning area. In addition, any new populations that
are found will be protected by the narrow endemic policy and the conditions for coverage
described in the MHCP Volume 2. In addition, the plan assures that all populations of short-
leaved dudleya discovered will be monitored and managed in a fashion that will detect and
minimize any negative impacts to the species. The avoidance, minimization, andor mitigation
measures identified in the MHCP Subregional Plan will reduce any impacts that may occur to
this species. Additionally, this species will benefit from the habitat that the ITA will preserve in
perpetuity. This Preserve will be adaptively managed, per the measures included in the MHCP
Subregional Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the action of approving the umbrella MHCP plan is not likely to jeopardize the continued
existence of this species. In addition, the City’s lack of coverage for this species is not likely to
jeopardize the continued existence of this species because the City will still implement the
narrow endemic policy and this species is currently not known within the City of Carlsbad.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 35 1
Lotus nuttaallianus (Nuttall’s lotus)
Status of the Species
Listing Status
Nuttall’s lotus is neither a State nor a Federally listed species. This species is on the California
Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code of 3-3-2,
and a California Natural Diversity Data Bank ranking of S 1.1. It is a narrow endemic species
under MHCP.
Species Description
Nuttall’s lotus is an annual plant in the Fabaceae family. It is a glabrous plant with prostrate or
ascending stem and pinnate or palmate, well spaced leaves. Stipules are gland-like and leaflets
are 4 to 10 millimeters long and, oblanceolate to obovate. Nuttall’s lotus may experience yearly
fluctuations in population size. Flowers are insect-pollinated. Although the seed dispersal
strategy of this species is unknown, it is possibly self-dispersed.
Distribution
Nuttall’s lotus is restricted to San Diego County and northern Baja California, Mexico (Skinner
and Pavlik 1994). In San Diego County, this species historically occurred from Camp Pendleton
(north end of the Santa Margarita estuary) southward along the coast to the U.S.-Mexican border.
The species is now known from fewer than 10 locations in the county, including Camp
Pendleton, Oceanside (mouth of the San Luis Rey River), Carlsbad (Batiquitos Lagoon),
Encinitas (San Elijo Lagoon), the San Diego River Flood Control Channel, the D Street Fill and
Marisma de Nacion, Silver Strand, and Border Field State Park. Nuttall’s lotus occurs along the
immediate coast and is associated with flat areas of coastal dunes and coastal scrub habitat.
Habitat Afinity
Nuttall’s lotus is found in coastal dunes and sandy coastal scrub. It ranges in elevation from 0 to
10 meters.
Life History
Nuttall’s lotus is an annual herb that may experience yearly fluctuations in population size. It
blooms from March to June and flowers are insect-pollinated. Although the seed dispersal
strategy of this species is unknown, it is possibly self-dispersed.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 352
Populatiqn Trend
Nuttall’s lotus is declining precipitously; it is now known in California from fewer than 10
occurrences.
Threats
Threats to this species include development, trampling, invasive nonnative plants, land
management activities, and edge effects.
Environmental Baseline
Within the MHCP, the level of survey effort for this species in the planning area is considered
relatively high. Since annual plants germinate in response to specific climatic conditions, this
species could be under represented, however, major populations of Nuttall’s lotus occur in
Oceanside (mouth of the San Luis Rey River), Carlsbad (Batiquitos Lagoon), and Encinitas (San
Elijo Lagoon). All of these populations are considered critical locations.
Effects of Action
Direct Efects
The MHCP will conserve at least 95 percent of point locations (6 of 8 locations are within the
FPA) and at least 92 percent of the critical locations and major populations. Of the three major,
critical populations, one will be entirely conserved within the FPA (Batiguitos Lagoon in
Carlsbad). The remaining two populations show a conservation level of 80 percent (San Luis
Rey River in Oceanside) and 96 percent (San Elijo Lagoon in Encinitas), respectively, when
overlaying the current FPA design on the location points. The critical location near the San Luis
Rey River in Oceanside occurs along a strip of beach habitat outside the FPA, and is potentially
subject to tramping, invasive nonnative plans, land management activities, and edge efects
associated with recreation and development. The population in San Elijo Lagoon in Encinitas
occurs in a relatively large block of habitat, although some plants are found near the edge of this
habitat where they are potentially susceptible to edge effects, including trampling. However, all
three major populations and critical locations must meet the narrow endemic standard which
consists of totally avoiding all narrow endemic populations listed as critical, regardless of
location. Thus, the critical locations at San Elijo Lagoon and the San Luis Rey River must be
100 percent conserved. Thus, no direct impacts to the major critical populations are expected
from this plan and any newly discovered populations would receive the benefit of the narrow
endemic policy.
In addition, the MHCP Subregional Plan requires the following conditions to be met for a City to
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Carlsbad Subarea Plan Biological and Conference Opinions (F’WS-SDG-847.4) 353 -
receive coverage for this species:
1.
2.
3.
4.
5.
- The major population and critical locations along the San Luis Rey River in Oceanside
an‘d at the San Elijo Lagoon in Encinitas must be conserved at a level consistent with the
critical location policy and managed as part of the preserve system.
The MHCP narrow endemic policy must be applied to any populations of this species,
including those already known and found in the future.
If not already established in the region by another entity, the MHCP management
program must establish a seed bank as a guarantee against extinction and to provide
source material for conservation and research activities. A seed bank must be established
within 15 years of permit issuance. Collections should be based on established guidelines
and subject to seed availability. Collected seed should be stored at an established seed
bank facility (e.g. Rancho Santa Ana Botanic Garden or San Diego Wild Animal Park).
Declining populations must be enhanced, and damaged habitat restored, if determined
necessary through monitoring. Enhancement may include introduction of plant materials
to existing populations, while restoration may include site-specific habitat improvement
activities. Unless analyses determine that there is no significant genetic variation
between populations, introduced plant materials must be from the parental population or a
population in proximity.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan shall be implemented.
Typical habitat for this species is coastal dunes (beach) and coastal scrub (coastal bluff scrub);
the percent conservation of these two habitats in the FPA is relatively low (9 acres, 18 percent).
However, 75 percent of the Nuttall’s lotus point localities in the planning area occur within
coastal salt marsh habitat. These locations likely represent inclusions of beach or scrub habitat
within the salt marsh that could not be differentiated due to the scale of vegetation mapping.
Nonetheless, it should be noted that conservation of salt marsh habitat is 272 acres (100 percent)
within the FPA. In addition, if new populations of Nuttall’s lotus are found, they will be
conserved according to the narrow endemic policy. Populations found in preserves will be
completely conserved and any new populations found outside the preserve and standards area
will be conserved at a minimum of 80 percent.
Indirect Effects
This plant could be indirectly impacted by the implementation of this plan. It is currently and
will continue to be vulnerable to edge effects, such as trampling and invasion of exotic species,
and vulnerable to unnatural fire regimes. However, the conditions for coverage of establishing a
seed bank, enhancing declining populations and restoring damaged habitat, and implementation
of all species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) will minimize these effects to ensure species persistence.
Conclusion
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 354 -
We have concluded that the MHCP Subregional Plan will not directly impact the known major
populatiops and critical locations of Nuttall’s lotus due to the application of the narrow endemic
policy and the conditions for coverage described in the MHCP Volume 2. In addition, the plan
assures that all populations of Nuttall’s lotus will be monitored and managed in a fashion that
will detect and minimize any negative impacts to the species. The avoidance, minimization,
andor mitigation measures identified in the MHCP Subregional Plan will reduce any impacts
that may occur to this species. Additionally, this species will benefit from the habitat that the
F’PA will preserve in perpetuity. This Preserve will be adaptively managed, per the measures
included in the MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline
for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the action of approving the umbrella MHCP plan is not likely to
jeopardize the continued existence and recovery of this species. In addition, the City’s lack of
coverage for this species is not likely to jeopardize the continued existence of this species
because the City will still implement the narrow endemic policy.
i
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Tetracoccus dioicus (Parry’s tetracoccus)
- 355
Status of ;he Species
Listing Status
Parry’s tetracoccus is neither a State nor a Federally listed species. This species is on the
California Native Plant Society’s list 1B with a R-E-D (Rarity-Endangerment-Distribution) code
of 3-2-2, and a California Natural Diversity Data Bank ranking of S2.2.
Species Description
Parry’s tetracoccus is a member of the Euphorbiaceae (spurge) family. It is an erect deciduous
spreading shrub 0.5 to 1.5 meters high, the young branches reddish, glabrous, slender. The
leaves are linear 2 to 3 centimeters long with petioles 1 to 2 millimeters long. Parry’s tetracoccus
blooms from April to May (Munz 1975).
Distribution
Parry’s tetracoccus occurs in Orange, Riverside, and San Diego counties, and in Baja California,
Mexico (Skinner and Pavlik 1994). In San Diego County, the species occurs sporadically
throughout the coastal foothills. Representative locations include Fallbrook (Red Mountain
Grade), Agua Tibia Mountains, Rainbow, San Marcos Mountains, Vista, Ramona, Barona
Valley, McGinty Mountain, Sequan Peak, Lee Valley, Dehesa, Tecate Junction, and Jacumba (H.
Wier pers. corn.; Beauchamp 1986). Rieser (1994) reports Parry’s tetracoccus from west of
Twin Oaks Valley Road, in the San Marcos Hills; however, appropriate habitat and soils in this
area occur just north of the MHCP boundary. One location of Parry’s tetracoccus was found in
the MHCP planning area in Escondido.
Habitat Afinity
Parry’s tetracoccus occurs in chaparral and coastal sage scrub and is typically associated with
gabbro soils. It is predominantly found on dry stony slopes in elevations between 165 to 1000
meters.
Life History
Parry’s tetracoccus is a shrugthat is likely a fire-adapted species that may be enhanced by fire;
however, the exact fire-response mechanism is not known. This species is presumably insect-
pollinated (Crepet 1983), and seeds are presumably self-dispersed.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Population Trend
- 356
Parry’s tetracoccus is slowly declining due to the threats identified below.
Threats
Parry’s tetracoccus is threatened by agriculture and residential development. It is particularly
susceptible to orchard expansion where chaparral is being cleared in North San Diego County for
avocados and citrus.
Environmental Baseline
The level of survey effort for this species in the planning area is considered moderate,
particularly in the northeastern portion of the planning area. Parry’s tetracoccus is known to
occur to the east and southeast, in the MSCP planning area and in the County of San Diego’s
unincorporated area. However, only one occurrence of Parry’s tetracoccus is known from the
MHCP planning area and no major populations or critical locations are identified for this species.
However, it has a high potential for occurrence in chaparral and scrub habitats in Escondido and,
possibly, San Marcos.
Effects of Action
Direct Efects
The MHCP Subregional Plan requires the following conditions be met for a city to receive
coverage for this species:
1. Fire management plans must be implemented for all conserved population to promote
biological goals (e.g. regeneration), while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel
reduction methods in urban areas), while limiting fire frequency and emergency access.
All species-specific monitoring and management identified in the MHCP Monitoring and
Management Plan (Volume 3) shall be implemented.
2.
At stated previously, there is only one known occurrence of this species in the MHCP planning
area and it is outside of the PA. Due to an existing development agreement between the
landowner and City of Escondido, this population has been approved for impacts, as noted in
Escondido’s Subarea Plan. The development agreement expires in 2007 at which time
preservation may be possible. However, for purposes of this biological opinion, we are assuming
this location will be impacted. The MHCP will conserve approximately 75 percent of potential
habitat which consists mostly of relatively large habitat blocks in northeast Escondido. If Parry’s
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 357 -
tetracoccus is detected in the future, the MHCP preserve design and avoidance policies are
expected go conserve the majority .of known locations.
Indirect Efsects
This plant could be indirectly impacted by the implementation of the MHCP Subregional Plan.
However, the MHCP requires the following conditions be met by a City to receive coverage for
this species: 1) Fire management plans must be implemented for all conserved populations to
promote biological goals (e.g. regeneration), while protecting individual plants and habitat from
frequent or high-intensity fires and fire suppression activities. Develop fire management
guidelines within conserved areas that incorporate controlled bums (or other fuel reduction
methods in urban areas), while limiting fire frequency and emergency access; and 2) All species-
specific monitoring and management identified in the MHCP Monitoring and Management Plan
(Volume 3) must be implemented.
Conclusion
We have concluded that the proposed action will not substantially impact this species since the
MHCP Subregional Plan is not permitting the loss of the one location identified in MHCP (it was
approved previously by the City of Escondido) and this is not considered a major population or
critical location. Rather, than plan is assuring that at least 75 percent of the potential habitat for
the species will be conserved and fire management and species specific management and
monitoring will be conducted for any identified occurrences. Thus, after reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the action of
approving the umbrella MHCP plan, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because there are no known
occurrences in the City and the City will be conserving all 69 acres of potential habitat.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Euphydryas editha quino (Quino Checkerspot Butterfly)
Listing Status
- 358
On August 4, 1994, the Service published a petition finding in the Federal Register (59 FR
39868) with a proposed rule to list the Quino checkerspot butterfly as endangered. We published
the final rule listing the species on January 16, 1997 (62 FR 2313). We proposed designating
critical habitat for the Quino checkerspot butterfly on February 7,2002 (66 FR 9476), and
finalized the designation on April 15,2002 (67 FR 18356). The draft recovery plan for this
species was issued in January 2001.
Species Description
The Quino checkerspot (Euphydryas editha quino) is a recognized subspecies of Edith’s
checkerspot (E. editha), and is a member of the Nymphalidae family, the brush-footed butterflies,
and the Melitaeinae subfamily, checkerspots and fritillaries. The Quino checkerspot differs from
the other Edith’s checkerspot subspecies in size, wing coloration, and larval and pupal
phenotypes (Mattoni et al. 1997). Among the other subspecies of Edith’s checkerspot, the Quino
checkerspot is moderate in size with a wingspan of approximately 4 cm (1.5 in). The dorsal (top)
side of its wings is covered with a red, black, and cream colored checkered pattern, the ventral
(bottom) side is mottled with tan and gold. Its abdomen generally has bright red stripes across
the top. Quino checkerspot larvae are black and have a row of nine, orange-colored tubercles
(fleshy/hairy extensions) on their back. Pupae are extremely cryptic and are mottled black and
blue-gray .
Distribution
The Quino checkerspot was historically distributed throughout the coastal slope of southern
California, including Los Angeles, Orange, Riverside, San Diego, and San Bernardino counties,
and northern Baja California, Mexico (Mattoni et al. 1997, U.S. Fish and Wildlife Service
database). That distribution included the westernmost slopes of the Santa Monica Mountains, the
Los Angeles plain and Transverse Ranges to the edge of the upper Anza-Borrego desert, and
south to El Rosario in Baja California, Mexico (Emmel and Emmel 1973, Mattoni et al. 1997,
U.S. Fish and Wildlife Service database). Although historical collection records allow for an
estimate of a species’ range, such records usually underestimate the number of historical sites
and extent of local distributions. Collectors tended to frequent well-known sites, and no
systematic or comprehensive surveys for the Quino checkerspot have ever been conducted
(Mattoni et al. 1997).
As recently as the 1950’s, collectors described the Quino checkerspot as occurring on every
coastal bluff, inland mesa top, and lower mountain slope in San Diego County and coastal
northern Baja California. These observations indicate that the Quino checkerspot was
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 359 -
historically widespread throughout the southern California landscape, and occurred in a variety of
vegetation types, including coastal sage scrub, open chaparral, juniper woodland, forblands, and
grasslands. By the 1970s, most of the coastal bluff and mesa habitats in southern California had
been urbanized or otherwise disturbed. However, the butterfly still occupied known habitat
locations inland and at higher elevations including Dictionary Hill, Otay Lakes, and San Miguel
Mountain in San Diego County, and the Gavilan Hills in Riverside County. By the middle
1980’s the species was thought to have disappeared from the known locations; the petition to list
the species in 1988 suggested that it might be extinct. Nonetheless, new populations were
discovered in Riverside County, the butterfly was rediscovered in San Diego County, and the
species continued to survive in northern Baja California, Mexico. Current information suggests
that the butterfly has been extirpated from Los Angeles, Orange, and San Bernardino Counties
and the MHCP planning area.
Habitat Afinities
In southwestern San Diego County, the primary host plants for the Quino checkerspot butterfly
are the dot-seed plantain (Plantago erecta), however Quino checkerspots may use other species
of plantain (Plantago spp.) and annual owl’s-clover (Castilleja exserta) as primary or secondary
host plants. Another apparently important, but only recently documented, primary host plant is
white snapdragon (Antirrhinum coulterianum; Pratt 200 1). The butterflies are generally found in
open areas and ecotone situations which may occur in a number of plant communities, including
grasslands, coastal sage scrub, chaparral, and sparse native woodlands. Open areas within a
given vegetation community seem to be a critical landscape feature for butterfly populations.
Optimal habitat appears to contain little or no invasive exotic vegetation, and especially, a well-
developed cryptogamic crust. In its adult stage, the Quino checkerspot uses a number of
flowering plants as nectar sources.
Life History
The life cycle of Quino checkerspot typically entails one generation of adults per year, with a 4-
to 6-week flight period occurring generally February to May, depending on weather conditions
(Emmel and Emmel 1973, Orsak 1978). During the flight period, adult butterflies move about
and search for nectar sources and mates. Females lay multiple masses of 20 to150 eggs (M.
Singer, C. Parmesan, and G. Pratt unpubl. data) with a single female capable of producing more
than 1,000 eggs. The eggs hatch in about 10 days and the larvae begin to feed immediately. At
lower elevations in San Diego County, the primary host plant for the Quino checkerspot butterfly
is the dot-seed plantain (Plantago erecta), however Quino checkerspots may use other species of
plantain (Plantago spp.) and annual 0~1~s-clover (Castilleja exserta). As the larvae grow, they
periodically shed their slun. Each phase between slun molts is referred to as an “instar” with the
first instar being the first larval stage after hatching.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
As summer approaches the food plants dry out. In their third or fourth instar, larvae enter into an
obligatory diapause. Diapause is a low-metabolic resting state that may last for a year or more,
depending on conditions. Diapause allows larvae to survive the regular seasonal climatic
extremes and also to better survive times of extended adverse conditions, such as drought. After
termination of diapause, larvae become active and feed. They then enter their pupal stage and
within two to six weeks, transform into the adults and emerge as butterflies. The butterflies feed,
disperse, reproduce, and then die.
360 -
Adult Quino checkerspots, and Edith’s checkerspots in general, are sedentary by nature and
generally fly close to the ground. Evidence from the bay checkerspot suggests that long-distance
dispersal is rare (Ehrlich 1961, Brussard and Ehrlich 1970, Ehrlich and Murphy 1981). Bay
checkerspots have been documented to move up to about 4.5 km (2.8 mi) to colonize distant
habitat patches (Harrison 1989). For the Quino checkerspot, many experts familiar with the
species believe that Quino populations separated by more than about 3 km (approximately 2 mi)
may be demographically isolated. However, responses to abiotic factors, such as weather, may
increase the distance butterflies will move (Ehrlich and Murphy 1987). Additionally, adult
Quino checkerspots are known to “hilltop.” Hilltopping is a behavior where male butterflies
form territories on hilltops, ridgelines, and other prominent geographic features in order to locate
mates.
Population Trend
Until as recently as the 1980s, the Quino checkerspot butterfly may have been one of the most
abundant butterflies in coastal southern California. More than 75 percent of the Quino
checkerspot’s historic range has been lost (Brown 1991; Service database), and more than 90
percent of the species’ coastal mesa and bluff habitat, where most historic records are located,
has been destroyed by habitat fragmentation, degradation, and loss (Service database). It is
estimated that Quino checkerspot population density range-wide has been reduced 95 percent by
human-caused impacts. Sources of habitat loss and habitat degradation include competition from
non-native plants, livestock grazing, off-road vehicle activity, and fire management practices.
Additionally, the butterfly larva are susceptible to predation by exotic invertebrates.
Recent studies have shown competitive exclusion by non-native plants may be accelerated by
nitrogen deposition from atmospheric pollution in southern California vegetation communities
(Allen et al. 1997, Eliason and Allen 1997, Padgett and Allen 1999, Padgett et al. 1999). The
non-native weeds may also directly out-compete the native plants, including butterfly host-plant
species. This effect has been documented in a native plant community that supports the Bay
checkerspot butterfly (E. e. bayensis) in the San Francisco Bay area (Weiss 1999). Not only does
the increase in weeds degrade the quality of the native habitat, it may also increase the frequency
or severity of wildfires, further impacting the vegetation community and the wildlife species
inhabiting it.
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36 1 Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Threats
..
The Quinb checkerspot butterfly is threatened primarily by urban and agricultural development,
non-native plant species invasion, off-road vehicle use, grazing, and fire management practices
(Federal Register 62: 2313). These threats destroy and degrade the quality of habitat and result
in the extirpation of local Quino checkerspot populations. Quino checkerspot butterfly
population decline likely has been, and will continue to be, caused in part by enhanced nitrogen
deposition, elevated atmospheric carbon dioxide concentrations, and climate change (Service, in
prep.). Nonetheless, urban development poses the greatest threat and exacerbates all other
threats. Activities resulting in habitat fragmentation or host or nectar plant removal reduce
habitat quality and increase the probability of local Quino checkerspot butterfly population
extirpation and species extinction. Other threats to the species identified in the final listing rule
(Federal Register 62: 2313) include illegal trash dumping and predation. Dumping, a
documented problem for some populations (G. Prattfide Federal Register 67: 18356), is
detrimental because of resulting habitat degradation and destruction. Over-collection by butterfly
hobbyists and dealers is a probable threat, although the magnitude of this activity is unknown.
Stamp (1984) and White (1986) examined the effects of parasitism and predation on the genus
Euphydryas, although it is not clear whether these mortality factors pose a significant threat to
this species. Predation by Argentine ants (Iridomynnex hurnilis) has been observed in colonies of
the butterfly in the laboratory (G. Prattfide Federal Register 67: 18356) and intense predation by
nonnative Brazilian fire ants (Solenopsis invicta) is likely where they co-occur with Quino
checkerspot butterflies (Porter and Savignano 1990). Brazilian fire ants were documented in
1998 in the vicinity of historic Quino checkerspot butterfly habitat in Orange County and have
subsequently been found in Riverside and Los Angeles Counties (California Department of Food
and Agriculture 1999).
Environmental Baseline
Currently, the Quino checkerspot may be locally extirpated from the MHCP area; however,
persistence of Quino habitat provides the opportunity for recolonization (no known localities in
database). There are currently no known major populations or critical locations in the MHCP.
Potential habitat for Quino checkerspot in the region includes vegetation communities with
relatively open areas that typically include patches of plantain (Plantago spp.) and a variety of
adult nectar sources. Owl’s clover (Castilleja spp.) is sometimes used as a secondary larval food
source (D. Faulkner pers. comm.). These habitats include vernal pools, lake margins (Emmel
and Emmel 1973), nonnative grassland, perennial grassland, disturbed habitat, disturbed
wetlands, and open areas within shrub communities (Mattoni et al. 1997).
Effects of Action
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Direct Efsects
362 -
The level’of conservation for this species is difficult to assess because the species is probably
extirpated from the MHCP area, and because the fine-scale at which Quino habitat elements
occur (e.g., populations of larval host plants) are not &stinpished at the MHCP scale of
mapping. Potential habitat will be 100 percent conserved where it occurs within wetlands, such
as vernal pools, lake margins, and disturbed wetlands, based on the no net loss of wetlands
policy. Grasslands are 3 1 percent conserved and shrub community conservation ranges from 44
percent to 82 percent across the MHCP area. Consequently, the Quino habitat occurring in these
ecological communities is expected to be conserved at similar rates. Where specific locations of
Quino habitat are known, they should be 100 percent conserved by avoidance of impacts and
ongoing management and monitoring, consistent with the narrow endemic and critical location
policies.
However, because the FPA for MHCP is unlikely to support a viable population or contribute
significantly to species recovery, a City may only receive coverage for Quino (to cover the
unlikely event that Quino is disc.overed within the planning area) if the City implements actions
to support species recovery outside the planning area. Thus, the following conditions must be
met by a City in order to receive coverage for this species under the MHCP program:
1. All newly discovered populations of Quino east of Interstate 15 shall be treated as critical
populations and avoided until criteria for delisting of the species have been met (Service
2000).
Where impacts cannot be totally avoided, larvae and possibly adults shall be salvaged for
relocation or other purposes under guidance of the wildlife agencies.
Where impacts cannot be totally avoided, they must be mitigated at appropriate MHCP
ratios for the affected vegetation communities in suitable Quino habitat outside of the
planning area, in a location that would help secure contiguous blocks of habitat identified
by the Service as important to species recovery.
2.
3.
Zndirect Efects
If Quino are discovered East of the 1-15 within the planning area, which is considered highly
unlikely, they will be avoided and treated as critical populations. They will receive all of the
benefits of preserve management and monitoring and adjacency standards to ensure the
population is not adversely affected by indirect effects.
Conclusion
We have concluded that the MHCP Subregional Plan will adequately conserve Quino if they are
discovered East of the 1-15 in the planning area by treating any newly discovered populations as
critical and avoiding impacts to such populations and, if they cannot be totally avoided, then
salvaged and mitigated appropriately outside of the planning area. In addition, the species would
be monitored and managed to avoid adverse indirect effects. Thus, after reviewing the current
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the action of
approving the umbrella MHCP plan, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because it is highly unlikely that
the species would be found in the City. Lastly, if the species was found in the City, any direct
impacts would need authority for take from the Service where the Service would analyze whether
the specific action would jeopardize the species.
363 -
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Scaphiopus [Spea] hammondii (Western spadefoot toad)
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Status of 'the Species
Listing Status
The western spadefoot toad is a State of California protected species. There is no Federal listing
for this species.
Species Description
Spea hammondii is a small (approximately 1.0 to1.5 inch), dusky green to gray toad of the family
Pleobatidae. The western spadefoot toad often has four irregular, light-colored stripes on the
back, skin tubercles tipped with orange or red, and a whitish to light gray venter lacking
markings (Stebbins 2003). Spadefoot toads are distinguished from true toads (genus Bufo) by
their vertically elliptical pupils, the presence of a wedge-shaped, glossy black spade on their hind
feet, teeth in their jaws, and rather smooth skin. The vocalization of the western spadefoot toad
is hoarse or snorelike and approximately 1 to 0.50 seconds in duration (Stebbins 2003).
Distribution
Historically, the western spadefoot toad ranged from Redding, California to northwestern Baja
California, Mexico (Stebbins 1985). In California, the species was found throughout the Central
Valley, and in the Coast Ranges and coastal lowlands from San Francisco Bay to Mexico. This
species has been extirpated from many locations within this range; however, the species still
persists in Orange, Riverside, San Diego, and Glenn.counties (Stebbins 2003). The elevational
range of the western spadefoot toad extends from near sea level to 1363 meters (Zeiner et al.
1988).
Habitat Afinity
Western spadefoot toads are primarily found in lowlands, and frequent washes, floodplains of
rivers, alluvial fans, playas, and alkali flats; however, this species also ranges into the foothills
and mountains (Stebbins 2003). This species prefers areas of open vegetation and short grasses,
with sandy or gravelly soil for burrowing. In addition, western spadefoot toads require temporary
rainpools lasting no less than three weeks and with water temperatures ranging from, 2 9"celcius
(C) to < 30°C (Brown 1996, 1997) for successful reproduction and metamorphosis (Jennings and
Hayes 1994).
Life History
The western spadefoot toad is almost completely terrestrial, utilizing aquatic habitats only to
reproduce (Jennings and Hayes 1994). Western spadefoot toads spend the majority of the year
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 365
burrowed in loose soil to a depth of at least one meter (Stebbins 1985). This species generally
becomes active on the surface following relatively warm (r 10-123°C) rains in late winter-spring
and fall; however, sucace activity may occur in any month between October and April if
appropriate climatic conditions are present (Morey and Guinn 1992).
-
Western spadefoot toads can form large (>lo00 individuals), highly vocal breeding aggregations,
although choruses are often smaller. Female western spadefoot toads deposit eggs in irregular,
small cylindrical clusters of 10-42, attached to plant stems or pieces of detritus in temporary rain
pools, or pools that have formed in ephemeral streamcourses (Storer 1925; Stebbins 1985).
Depending on the climatic conditions (Le, amount of rainfall and temperatures), oviposition may
occur between late February and late May (Storer 1925, Burgess 1950, Feaver 1971, Stebbins
1985). Eggs hatch in 0.6-6 days, depending on the temperature (Brown 1967), and larval
development can be completed in 3-1 1 weeks depending on food availability and temperatures
(Burgess 1950; Feaver 1971).
Adult western spadefoot toads can eat roughly 11 percent of their body mass at a single feeding
(Dimmitt and Ruibal 1980b), and can probably acquire enough energy to survive the long annual
dormancy interval (8-9 months) in a few weeks (Jennings and Hayes 1994). The diet of the
westem spadefoot toad is composed of crickets, butterflies, beetles, flies, ants, and earthworms
(Morey and Gullin 1992).
Population Status
Western spadefoot toad population numbers and densities are not currently known because
insufficient data is available on the species’ normal population dynamics and on habitat
characteristics that correlate with density; however, limited available data suggest that spadefoot
populations are sometimes large and may include aggregations of up to 1,000 chorusing males
(Stebbins 195 1; Jennings and Hayes 1994). In addition, current data suggest that approximately
80 percent of historically occupied western spadefoot habitat in the Central Valley and Southern
California has been developed or converted to uses that are incompatible with the species
reproduction and recruitment requirements (Jennings and Hayes 1994). In northern and central
California, habitat loss has been less severe; however, it is estimated that approximately 30
percent of historically occupied habitat in these areas has been developed or converted to uses
that are incompatible with the species reproduction and recruitment requirements (Jennings and
Hayes 1994).
Threats
Because western spadefoot toad habitats (i.e., lowlands, vernal pools) are favored sites for
agricultural and urban development many populations of spadefoot toads have been reduced in
size or extirpated due to extensive habitat loss (Jennings and Hayes 1994). Habitat
fragmentation by urban development, agricultural conversion, and road construction is also a
threat to western spadefoot toad populations throughout California. Although the migratory and
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
spatial requirements of the western spadefoot toad are poorly understood, it is likely that habitat
fragmentqtion will result in smaller, more isolated populations. In addition to habitat loss and
habitat fragmentation, the major threats to western spadefoot toad populations are from vehicle-
related mortality and the introduction of exotic species, including mosquito fish (Gambusia sp.),
other fish species, and bullfrogs (Rana catesbiana), which prey on tadpoles and metamorphs
(Jennings and Hayes 1994)
366 -
Environmental Baseline
Within MHCP there are approximately 3,768 acres of potential habitat, of which approximately
708 acres are within the City2. Habitat includes freshwater, natural floodchannel/streambed, and
freshwater marsh aquatic vegetation communities, and all riparian vegetation communities.
Upland habitats were not quantified. However, portions of these habitat types may not be
suitable for this species (Le. lack of friable soils, ponding water, and/or open vegetation),
therefore the amount of suitable habitat within MHCP and the City will likely be less.
Population estimates have not been completed for this species due to a lack of survey effort.
Within MHCP, western spadefoot toads have been observed at Buena Vista Lagoon, San Marcos
Creek, and Page Creek. No major populations or critical locations were designated.
Effects of the Action
Direct Efsects
Few direct effects to the western spadefoot toad are expected from the implementation of the
MHCP Subregional and City’s subarea plan. The MHCP no net loss policy for wetlands will
substantially benefit this species. Therefore, all wetland functions and values within the MHCP
are expected to be 100 percent conserved. Within the FPA, 3 of 4 known location points will be
conserved. More importantly, the following conditions must be met in order for a City to receive
coverage for this species:
1. As part of the project review process (e.g. CEQA) for individual projects, a qualified
biologist will survey, using approved survey methods, all areas of the property containing
potentially suitable breeding habitat for western spadefoot toad (ephemeral ponds, vernal
pools, washes, riparian areas) or upland foraging habitat (open scrublands, woodlands,
grasslands) that is contiguous with potential breeding habitat. Surveys will also identify
any known or likely movement corridors used by toads, including existing road crossings or
culverts, bridges, or other features used by dispersing toads. They will also identify
locations where road undercrossings and fencing could be created to benefit toads by
2The habitat acreages are from Volume 2 of the MHCP. The HMP has slightly different
numbers for Carlsbad due to recent updates, however for consistency we are using the estimates
in MHCP Volume 2, so that the reader can see the relationship between MHCP and the HMP.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 367
2.
3.
-
reducing roadkill on either new or existing roadways. Surveys shall occur prior to any
proposed impact both inside and outside of the FPA. Surveys shall be conducted when
impacts to western spadefoot toad could occur as a result of direct or indirect impacts by
placement of the project in or adjacent to occupied habitat or through creation of suitable
conditions for nonnative predators (e.g., bullfrogs). All pertinent agencies (including
CDFG, Service, and County of San Diego Vector Control Program) will be informed about
the location of any toad populations.
Although western spadefoot toads is not an MHCP Narrow Endemic, all currently known
or future discovered populations will be treated consistent with the requirements of the
Narrow Endemics Policy, including the following: a) maximum avoidance of impacts to
the degree feasible while maintaining reasonable use of the property; b) for unavoidable
impacts, species-specific mitigation designed to minimize adverse effects to specie viability
and to contribute to species recovery; and c) no more than 5 percent gross cumulative loss
inside the FPA or 20 percent gross cumulative loss outside the FPA.
Projects having direct or indirect impacts to the western spadefoot toad shall adhere to the
following measures to avoid or reduce impacts:
The removal of breeding pools, streams, and adjacent dispersal/adult burrowing areas
shall be avoided to the maximum extent practicable. Determination of adequate
avoidance and minimization of impacts shall be consistent with Sections 3.6 and 3.7
of the MHCP plan. Deviations from these guidelines shall require written
concurrence of the USFWS and CDFG. For temporary impacts, the work site shall be
retumed to preexisting contours and revegetated with appropriate native species. All
revegetation shall occur at the ratios specified in Section 4.3 of the MHCP plan. All
revegetation plans shall be prepared and implemented consistent with Appendix C
(Revegetation Guidelines) and shall require written concurrence of the USFWS and
CDFG. If written objections are not provided by the wildlife agencies within 30 days
of receipt of written request for concurrence by the local jurisdiction, then the
deviation may proceed as approved by the local agency. The wildlife agencies shall
provide written comments specifying wildlife agency concerns.
Projects proposing impacts to occupied habitat during the breeding season (January
through May) shall be required to trap emerged adults and relocate them to
appropriate, conserved habitat areas within the FPA. Trapping of larvae (tadpoles)
and juveniles shall be required if they are found in breeding pools. Captured larvae or
juveniles shall be relocated to appropriate, conserved habitat areas within the FPA.
Projects shall be carried out consistent with Appendix B (Standard Best Management
Practices).
Project-construction vehicle travel shall be limited to daylight hours, as western
spadefoot toad use roadways primarily during nighttime hours. New roads adjacent to
occupied toad habitat shall include provisions for barriers to minimize traffic
mortality. Culverts and fencing designed to funneI toads through culverts shall be
included within the road design to allow safe crossings between potential habitat areas
(including both wetland breeding areas and upland foraging areas). Culverts and
fences will be located to maximize value to toads, unless this is totally precluded by
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 368 -
engineering constraints, in which case the biologically most beneficial design that is
feasible will be implemented.
4.
5.
6.
Projects that cannot be conducted without placing equipment or personnel in sensitive
habitats shall be timed to avoid the breeding season of the western spadefoot toad
when eggs and tadpoles are present.
Silt fencingdrift fence and pitfall traps shall be installed around the impact area
adjacent to occupied western spadefoot toad habitat at least 21 days prior to impact to
minimize access by toads and to allow for removal of western spadefoot toad from the
impact area. A biologist experienced with the identification, handling, and ecology of
toads shall implement and oversee proper execution of the toad exclusion fencing,
relocation efforts, and monitoring. The exclusion fencing shall be maintained until
the completion of all construction activities within or adjacent to occupied western
spadefoot toad habitat. For the duration of construction, the enclosure shall be
surveyed on a daily basis early in the morning and any toads that may have breached
the fencing shall be relocated.
Bullfrogs and other exotic species that prey upon or displace toads should be removed
from the site as part of an ongoing management plan.
Western spadefoot toad populations within the FPA shall be managed to provide adjacent
adult burrowing habitat, control of predatory or competing nonnative species such as
bullfrogs and mosquito-fish, and control of water pollution and nonnative vegetation in the
breeding pools and adjacent burrowing habitat. Activities that may degrade habitat value
will be precluded, including draining of wetlands, mosquito control, livestock grazing, off-
road vehicle activity, and degradation of water quality. Management will actively
coordinate with any pertinent Vector Control programs to develop methods to minimize
impacts on spadefoot toads and their habitat, such as changing the timing of any pesticide
spraying or use of other alternative control techniques.
Wetlands that contain suitable, unoccupied breeding habitat aras within the FPA will be
delineated and protected from development or uses that negatiely affect runoff and ponding
processes to ensure adequate ponding during normal (e.g., not El Nino) rain years. These
areas shall be the recipient areas for relocation efforts for approved projects that impact
occupied western spadefoot toad habitat.
Any wetlands created for mitigation for impacts to wetlands occupied by western spadefoot
toads must be demonstrated to be capable of supporting the species prior to impacts, to
ensure no net loss of occupied breeding habitat.
Direct impacts to spadefoot toads may also result from the allowance of activities in preserve
areas, such as construction and use of trail networks, roads, other recreational use areas, fire
management techniques, and landscaping of adjacent properties.
Indirect Eflects
Indirect impacts are anticipated with the implementation of the MHCP Subregional and City’s
Subarea plans, and have the potential adversely affect western spadefoot toads. These indirect
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
impacts include habitat fragmentation, night lighting, human disturbance, and habitat
degradation, as generally explained and applicable in the “General Indirect Effects’’ section.
369 -
Although the migratory and spatial requirements of the western spadefoot toad are poorly
understood, it is likely that habitat fragmentation, due to urban development and associated road
networks within the planning area, will result in smaller, more isolated populations of this
species. The isolation of populations of western spadefoot toads may reduce movements by
individuals and genetic exchange between populations, resulting in a greater risk of extirpation
within the planning area. This may also result in a reduction in the potential for recolonization of
areas from which the toads have disappeared.
Implementation of the plans may also indirectly affect the western spadefoot toad by increasing
the amount of lighting. Evening lights are known to upset the behavior of snakes and other
nocturnal animals (Lieberman 2002) and may have adverse impacts to this species near
developed areas.
Other indirect effects to the western spadefoot toad may result from an increase in road-kill
impacts as development and associated road networks fragment the species habitat. In addition,
contaminants from road materials, leaks and spills also could adversely impact toads by
contaminating the water in wetlands used by this species for reproduction. Lastly, activities
occurring within the Subarea that produce low frequency noise and/or vibration in or near habitat
for western spadefoot toads may be detrimental to the species. Noise and vibrations may illicit
fossorial species, such as the western spadefoot toad, to break dormancy and emerge from their
burrows, thereby resulting in mortality or reduced productivity.
The Subarea plan does not provide specific conservation measures for this species; however, the
conditions for coverage in the MHCP as described above will substantially reduce the indirect
effects described above. Thus, as a result of the measures incorporated into the MHCP
Subregional Plan, we anticipate few indirect impacts to this species.
Conclusion
As described in the analyses above, we have determined that the MHCP Subregional Plan may
adversely affect the western spadefoot toad. However, the plan assures that impacts to breeding
and upland habitat will be avoided, minimized and mitigated appropriately. After reviewing the
current status of this species, the environmental baseline for the action area, the effects of the
proposed action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
Subregional Plan is not likely to jeopardize the continued existence and recovery of this species.
In addition, the City’s lack of coverage for this species is not likely to jeopardize the continued
existence and recovery of this species because protections will be afforded the species through
the no net loss of wetland policy and the wetland buffer policy.
369
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Bufo califomicus (Arroyo toad)
Status of the SDecies
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Listing Status
The Service listed the arroyo toad as endangered on December 16, 1994 (59 FR 63264) and a
recovery plan was published in July 1999 (U.S. Fish and Wildlife Service 1999e). This species is
considered a species of special concern by the State of California. Critical habitat was designated
on February 7,2001 (66 FR 9414), however, this designation has since been vacated until a new
proposal is submitted. Critical habitat was designated on February 7, 2001 (66 Federal Register
9414); however, this designation was vacated by a Federal Court on October 30,2003, due to an
economic analysis that was not sufficiently broad (See Building Ind. Legal Defense Found. v.
Norton, 231 F. Supp. 100 (D.D.C. 2002)). The Service proposed critical habitat for the arroyo
toad on April 28,2004 (69 FR 23254).
Species Description
B~fo califomicus is a small, dark-spotted toad of the family Bufonidae. The parotoid glands,
located on the top of the head, are oval-shaped and widely separated. A lighdpale area or stripe
is usually present on these glands and on top of the eyes. B. califomicus underside is buff-
colored and usually without spots (Stebbins 1985). Recently metamorphosed individuals will
easily blend with the substrate and are usually found adjacent to water. At the time of listing, the
arroyo toad was described as the “arroyo” subspecies of the southwestern toad (Bufo
rnicroscaphus califomicus). Gergus (1998) recently published genetic justification for the
reclassification of the arroyo southwestern toad as a full species (i.e., arroyo toad [BK~o
califomicus]).
Distribution
The current distribution of the arroyo toad in the United States is from the Salinas River Basin in
Monterey County, south to the Tijuana River and Cottonwood Creek Basin along the Mexican
Border. Arroyo toads are also known from a seemingly disjunct population in the Arroyo San
Simeon River System, about 16 kilometers (10 miles) southeast of San Quintin, Baja California
(Gergus et al. 1997). Although the arroyo toad occurs principally along coastal drainages, it also
has been recorded at several locations on the desert slopes of the Transverse range (Patten and
Myers 1992, Jennings and Hayes 1994). The current elevational range for most arroyo toad
populations in San Diego County is about 300 to 1,400 meters (1,000 to 4,600 feet), although
they were historically known to extend into the lower portions of most river basins (U.S. Fish
and Wildlife Service 1999e).
Records exist for the San Luis Rey River in the immediate vicinity of Bonsall and on Camp
Pendleton as well as locations in the MSCP planning area.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 371
Ha bitat Afin ily
Arroyo toads require shallow, slow-moving streams, and riparian habitats that have natural
flooding regimes which maintain areas of open, sparsely vegetated, sandy stream channels and
terraces (US. Fish and Wildlife Service 1999e). Stream order, elevation, and floodplain width
are important factors in determining the size and long-term viability of a population of arroyo
toads (Sweet 1992, Barto 1999, Griffin 1999). Streams with the greatest potential to support
self-sustaining populations are typically of a high stream order (i.e., 3d to 6* order), at low
elevations (below 3,000 feet), with wide floodplains (Sweet 1992, Barto 1999, Griffin 1999).
Optimal breeding habitat consists of low gradient stream reaches that have shallow pools with
fine textured substrates (i.e., sand or gravel). Upland habitats used by arroyo toads during both
the breeding and non-breeding seasons include alluvial scrub, coastal sage scrub, chaparral,
grassland, and oak woodland (Holland 1995, Griffin et al. 1999, US. Fish and Wildlife Service
1999e). Arroyo toads have also been found in agricultural fields (Griffin et al. 1999).
Life History
Arroyo toad larvae feed on loose organic material such as interstitial algae, bacteria, and diatoms.
They do not forage on macroscopic vegetation (Sweet 1992, Jennings and Hayes 1994). Juvenile
toads rely on ants almost exclusively (U.S. Fish and Wildlife Service 1999e). By the time they
reach 17 to 23 mm in length, they take more beetles, along with the ants (Sweet 1992, U.S. Fish
and Wildlife Service 1999e). Adult toads probably consume a wide variety of insects and
arthropods including ants, beetles, spiders, larvae, caterpillars, and others.
Breeding typically occurs from February to July on streams with persistent water (Griffin et al.
1999). Female arroyo toads must feed for a minimum of approximately two months to develop
the fat reserves needed to produce a clutch of eggs (Sweet 1992). Eggs are deposited and larvae
develop in shallow pools with minimal current and little or no emergent vegetation. The
substrate in these pools is generally sand or fine gravel overlain with silt. Arroyo toad eggs hatch
in 4 to 5 days and the larvae are essentially immobile for an additional 5 to 6 days (Sweet 1992).
They then begin to disperse from the pool margin into the surrounding shallow water, where they
spend an average of 10 weeks (Sweet 1992). After metamorphosis (June-July), the juvenile
toads remain on the bordering gravel bars until the pool no longer persists (usually from eight to
twelve weeks depending on site and yearly conditions) (Sweet 1992). Most individuals become
sexually mature by the following spring (Sweet 1992).
This species has been observed moving approximately 1.6 kilometers (1 mi) within a stream
reach and 1 kilometer (0.6 mi) away from the stream, into native upland habitats (Holland 1995,
Sweet 1992) or agricultural areas (Griffin et al. 1999). Movement distances may be regulated by
topography and channel morphology. Griffin (1999) reported a female arroyo toad traveling
more than 300 meters (948 ft) perpendicular from a stream and Holland (1998) found arroyo
toads 1 .OS kilometers (0.7 mi) from a water course. Arroyo toads are critically dependent on
37 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
upland terraces and the marginal zones between stream channels and upland terraces during the
non-breeding season, especially during periods of inactivity, generally late fall and winter (Sweet
1992).
372 -
Population Trend
Arroyo toad population numbers and densities are not currently known because insufficient data
is available on the species' normal population dynamics and on habitat characteristics that
correlate with density. This species was historically found in at least 22 river basins in southern
California from the upper Salinas River system in Monterey County to San Diego County and
southward to the vicinity of San Quintin, Baja California, Mexico. They have been extirpated
from an estimated 75 percent of their former range in the United States and they now occur
primarily in small, isolated areas in the middle to upper reaches of streams.
7'hreats
Because arroyo toad habitats (i.e., broad, flat floodplains in southern California) are favored sites
for flood control projects, agriculture, urbanization, and recreational facilities such as
campgrounds and off-highway vehicle parks, many arroyo toad populations were reduced in size
or extirpated due to extensive habitat loss from 1920 to 1980 (U.S. Fish and Wildlife Service
1999e). The loss of habitat, coupled with habitat modifications due to the manipulation of water
levels in many central and southern California streams and rivers, as well as predation from
introduced aquatic species, caused arroyo toads to disappear from a large portion of their
previously occupied habitat in California (Jennings and Hayes 1994). Currently, the major
threats to arroyo toad populations are from stream alteration, introduction of exotic species,
urban and rural development, mining, recreation, grazing, drought, wildfire, and large flood
events.
,
Critical Habitat
The Service has proposed to designate 138,713 acres of arroyo toad critical habitat in Monterey,
Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside, Orange, and San Diego
Counties, California.
The primary constituent elements were identified as the following:
1. Rivers or streams with hydrologic regimes that supply water to provide space, food, and
cover needed to sustain eggs, tadpoles, metamorphosing juveniles, and adult breeding
toads. Specifically, the conditions necessary to allow for successful reproduction of
arroyo toads are: a) breeding pools with areas less than 12 in (30 cm) deep; b) areas of
flowing water with current velocities less than 1.3 ft per second (40 cm per second); and
c) surface water that lasts for a minimum length of 2 months in most years, i.e., a
sufficient wet period in the spring months to allow arroyo toad larvae to hatch, mature,
and metamorphose.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 373 -
2. Low-gradient stream segments (typically less than 6 percent) with sandy or fine gravel
substrates that support the formation of shallow pools and sparsely vegetated sand and
kavel bars for breeding and rearing of tadpoles and juveniles.
A natural flooding regime, or one sufficiently corresponding to a natural regime, that
will periodically scour riparian vegetation, rework stream channels and terraces, and
redistribute sands and sediments, such that breeding pools and terrace habitats with
Riparian and adjacent upland habitats (particularly alluvial streamside terraces and
adjacent valley bottomlands that include areas of loose soil where toads can burrow
underground) to provide foraging and living areas for subadult and adult arroyo toads.
Stream channels and adjacent upland habitats that allow for migration to foraging areas,
overwintering sites, dispersal between populations, and re-colonization of areas that
contain suitable habitat.
3.
- scattered vegetation are maintained.
4.
5.
Arroyo toads are not distributed uniformly throughout the critical habitat units. Arroyo toad
breeding habitat is patchily distributed along the stream courses, and the same is true of
appropriate upland habitat. Some areas primarily provide for migration and dispersal between
breeding and foraging habitats or allow for dispersal to additional breeding pools that will
accommodate increased populations during favorable years. Habitat conditions within streams
can change rapidly in response to streamflows and other factors, such as the development and
shifting of sand and gravel bars, and creation and disappearance of pools. Terrace and upland
habitats, although more stable than streambed and riparian habitats, may change as a result of
rainfall, earthquakes, fires, and other natural events. These factors may cause the habitat
suitability of given areas to vary over time, thus affecting the distribution of arroyo toads. The
combination of appropriate aquatic, riparian, and upland habitats forms ecologically functional
units. These features and the lands that they represent are essential to the conservation of the
arroyo toad.
Environmental Baseline
Documented arroyo toad locations are lacking for the MHCP area, except for one recent record
outside the FPA near the eastern boundary of Oceanside. No major populations or critical
locations have been identified in the MHCP planning area. It is possible that the species may be
functionally extirpated from the MHCP planning area.
Arroyo toads are not believed to be present within the City of Carlsbad, based on the lack of
available habitat and the absence of observations.
No critical habitat for the arroyo toad was designated within the City. However, critical habitat
was designated within the MHCP planning area outside of the City.
1,375 acres of arroyo toad critical habitat are designated within the MHCP planning area. More
specifically, all of the critical habitat is located in the City of Oceanside from the San Luis Rey
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 374 -
flood control channel to the eastern boundary of the City of Oceanside and the San Luis Rey
River. Three hundred twelve acres are located within the FPA for the City of Oceanside.
Although the entire San Luis Rey River throughout the City of Oceanside consists of either a pre-
approved mitigation area, publidagency ownership, hardline preserve, or mitigation bank, the
1,063 acres not within the PA are within suitable upland habitat necessary for arroyo toad
movement, burrowing and estivation.
Effects of the Action
Direct ERects
All potential breeding habitat within the MHCP will be 100 percent conserved based on the no
net loss policy of the MHCP. However, the fluvial processes that create and maintain the sand
and gravel bars required for breeding are not protected by this plan. Furthermore, few riparian
corridors in the planning area are buffered by sufficient upland habitats to ensure that all life
requisites can be met, and some such areas may be insufficiently conserved within the FPA.
In addition to the wetland avoidance, minimization, and mitigation policies, the MHCP requires
the following species specific conditions be met for a city to receive coverage for this species:
1. As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist possessing a Section 10(a)l(A) research permit for
this species must survey all areas of the property containing potentially suitable
breeding habitat for arroyo toads, including but not limited to survey areas included on
the MHCP Database Records Map, which shows potential suitable arroyo southwestern
toad habitat, or upland foraging habitat that is contiguous with potential breeding
habitat. Surveys shall be conducted by a qualified biologist using approved survey
protocol. Surveys shall occur prior to any proposed impact as part of the project review
process (e.g., CEQA process) both within and outside of the FPA. Surveys shall be
conducted when impacts to arroyo toad could occur as a result of indirect impacts by
placement of the project adjacent to occupied habitat or through creation of suitable
conditions for nonnative predators (e.g., bullfrogs, freshwater game fish).
Any newly found population with more than 25 adults shall be treated consistent with
the Critical Population Policy (Appendix D), including: (a) maximum avoidance of
impacts, to the degree feasible while maintaining reasonable use of the property; (b) for
unavoidable impacts, species-specific mitigation designed to result in no net loss in
species viability and to contribute to species recovery; and (c) no more than 5 percent
gross cumulative loss, regardless of location inside or outside of the PA.
Arroyo toad populations within the FPA shall be managed to provide adjacent adult
burrowing habitat, control of predatory or competing nonnative species such as
bullfrogs and mosquito-fish, and control of water pollution and nonnative vegetation in
the breeding pools and adjacent burrowing habitat. Activities that may degrade habitat
value will be precluded, including draining of wetlands, mosquito control, livestock
grazing, off-road vehicle activity, and degradation of water quality. Management will
2.
3.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 375 -
actively coordinate with any pertinent Vector Control programs to develop methods to
minimize impacts on arroyo toads and their habitat, such as changing the timing of any
besticide spraying or use of other alternative control techniques.
Sufficient upland foraging habitat shall be conserved and managed adjacent to any
newly found population to promote continued viability of the population. “Sufficient
Upland Foraging Habitat” shall be defined as all natural habitat or agricultural land
contiguous with and within 1 kilometer (0.6 mile) of the edge of suitable breeding
habitat, excluding habitat patches not expected to be reachable by toads due to
intervening development or movement barriers (e.g., large or heavily traveled roads).
Conservation of less than 1 kilometer (0.6 mile) of contiguous foraging habitat shall
require USFWS and CDFG written concurrence within 30 days of receipt of written
request for concurrence by the local jurisdiction.
Suitable unoccupied habitat preserved within the FPA shall be managed to maintain or
mimic effects of natural fluvial processes (e.g., periodic substrate scouring and
deposition) and to maintain suitable low-gradient sandy stream habitat. Applicable
Regional Water Quality Control Board criteria shall be adhered to.
Natural riparian connections with upstream riparian habitat shall be maintained to
ensure linkage to suitable occupied and unoccupied habitat within the MHCP, County
MSCP North Segment, and City of San Diego MSCP Subarea Plan.
Projects impacting occupied arroyo toad habitat, or potential habitat contiguous with
and within 1 kilometer (0.6 mile) of occupied habitat, shall adhere to the following
measures to avoid or reduce impacts:
a.
4.
5.
6.
7.
The removal of native vegetation and habitat shall be avoided and minimized to
the maximum extent practicable. Determination of adequate avoidance and
minimization of impacts shall be consistent with Sections 3.6 and 3.7 of the
MHCP plan. Deviations from these guidelines shall require written concurrence
of the USFWS and CDFG. For temporary impacts, the work site shall be
returned to preexisting contours and revegetated with appropriate native species.
All revegetation shall occur at the ratios specified in Section 4.3 of the MHCP
plan. All revegetation plans shall be prepared and implemented consistent with
Appendix C (Revegetation Guidelines) and shall require written concurrence of
the USFWS and CDFG. Lf written objections are not provided by the wildlife
agencies within 30 days of receipt of written request for concurrence by the local
jurisdiction, then the deviation may proceed as approved by the local agency.
The wildlife agencies shall provide written comments specifying wildlife agency
concerns.
All habitat destroyed that is not in the approved project footprint shall be
disclosed immediately to the jurisdictional city, USFWS, and CDFG, and shall
be compensated at a minimum ratio of 5: 1.
Projects shall be carried out consistent with Appendix B (Standard Best
Management Practices).
Project-construction vehicle travel shall be limited to daylight hours, as arroyo
toads use roadways primarily during nighttime hours. New roads adjacent to
b.
c.
d.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 376
occupied toad habitat shall include provisions for barriers to minimize traffic
mortality. Culverts and fencing designed to funnel toads through culverts shall
be included within the road design to allow safe crossings.
Projects shall be designed to avoid the placement of equipment and personnel
within the stream channel or on sand and gravel bars, banks, and adjacent
upland habitats used by arroyo toads.
Projects that cannot be conducted without placing equipment or personnel in
sensitive habitats shall be timed to avoid the breeding season of the arroyo toad
(generally March through August) when eggs and tadpoles are present. To
minimize further effects to breeding populations and to reduce sedimentation
and erosion, such projects shall be timed so that work within or near the stream
channel is conducted during the dry season when flows are at their lowest or are
nonexistent.
Silt fencinddrift fence and pitfall traps shall be installed around the impact area
adjacent to occupied arroyo toad habitat at least 21 days prior to impact to
minimize access by toads and to allow for removal of arroyo toads from the
impact area. A permitted biologist experienced with the identification, handling,
and ecology of the arroyo toad shall implement and oversee proper execution of
the toad exclusion fencing, relocation efforts, and monitoring. The exclusion
fencing shall be maintained until the completion of all construction activities
within or adjacent to occupied arroyo toad habitat. For the duration of
construction, the enclosure shall be surveyed on a daily basis early in the
morning, and any toads that may have breached the fencing shall be relocated.
Bullfrogs and other exotic species that prey upon or displace arroyo toad shall
be removed from the site as part of an ongoing management plan.
To minimize injury to or mortality of individual arroyo toads, the USF'WS may
authorize qualified project biologists to relocate individual arroyo toads to
nearby suitable habitat. Authorization will be granted only to jurisdictions with
signed implementing agreements and issued permits that cover arroyo toads and
will require coordination with the wildlife agencies and written concurrence.
Require road projects (including new roads or improvements to existing roads)
passing within 1 kilometer (0.6 mile) of known breeding habitats to consider,
based on an appropriate, site-specific biological study approved by the wildlife
agencies, whether creating underpasses and associated toad fencing would
benefit toad populations in the area. Where there would be benefits to allowing
toads safe dispersal routes across roads, appropriately designed underpasses and
associated toad fencing shall be constructed as part of the project.
-
e.
f.
g.
h.
i.
j-
Indirect Effects
Indirect impacts are not anticipated, however considering a future presence the implementation
of the Subarea plan may have the potential to cause adverse affects to arroyo toads within the
Subarea. These indirect impacts include night lighting, human disturbance, depredation by
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 377 -
domestic pets, and habitat degradation, as generally explained and applicable in the “General
Indirect Effects” section.
Conclusion
As described in the analyses above, we have determined that the MHCP Subregional Plan may
adversely affect the arroyo toad. However, the plan assures that impacts to breeding and upland
habitat will be avoided, minimized and mitigated appropriately. After reviewing the current
status of this species, the environmental baseline for the action area, the effects of the proposed
action, and the cumulative effects, it is the Service’s biological opinion that the MHCP
subregional plan is not likely to jeopardize the continued existence or recovery of this species. In
addition, the City’s lack of coverage for this species is not likely to jeopardize the continued
existence of this species because it is highly unlikely that the species would be found in the City.
Lastly, if the species was found in the City, any direct impacts would need authority for take from
the Service where the Service would analyze whether the specific action would jeopardize the
species.
We have also determined that the MHCP Subregional Plan may adversely affect arroyo toad
critical habitat. However, the critical habitat will be able to remain functional to ensure species
conservation based on the following: 1) all breeding habitat within the MHCP planning area
would be protected through the wetland protection program; 2) any newly found population with
more than 25 adults will be treated consistent with the Critical Population Policy; 3) sufficient
upland foraging habitat (natural habitat or agricultural land contiguous with and within 1
kilometer (0.6 mile) of the edge of suitable breedmg habitat) will be conserved and managed
adjacent to any newly found population to promote continued viability of the population; 4)
suitable unoccupied habitat preserved within the FPA will be managed to maintain or mimic
effects of natural fluvial processes and to maintain suitable low-gradient sandy stream habitat; 5)
projects impacting occupied arroyo toad habitat, or potential habitat contiguous with and within 1
kilometer (0.6 mile) of occupied habitat, are required to avoid or reduce impacts by
implementing the 10 measures described in the direct effects section. Thus, after reviewing the
current status of the critical habitat, the environmental baseline for the action area, the effects of
the proposed action and the cumulative effects on critical habitat, it is the Service’s biological
opinion that the MHCP Subregional Plan is not likely to adversely modify arroyo toad critical
habitat.
377
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4)
Clemmys mamorata pallida (Southwestern pond turtle)
Status of the Species
- 378
Listing Status
There is no Federal listing for this subspecies however, the southwestern pond turtle is on the
State of California species of special concern list.
Species Description
Clemmys mannorata rnarmorata (northwestern pond turtle) and Clemmys marmorata pallida are
the two subspecies recognized. C. m. marmorata is distinguished by a pair of well-developed
triangular inguinal scutes on the bridge, where C. m. pallida has poorly developed inguinal scutes
(absent in 60 percent of individuals). In addition, C. m. mamorata has a pale throat in contrast
with its head, while C. m. pallida has a more uniform light color of the throat and neck (Stebbins,
1985; Lovitch, 1999).
Distribution
The historical range of the southwestern pond turtle extended along most of the west coast of
North America, primarily west of the Cascade-Sierra crest, from western British Colombia to
northern Baja California (Ernst et al., 1994). Currently, it ranges south of San Francisco Bay to
northern Baja California, Mexico, and integrates with the northwestern pond turtle (C.m.
mannorata) over a large area in central California (Bury, 1970, Stebbins, 1985). The presence of
pond turtles in the Mojave Desert has been established by fossils in the Camp Cady area, dating
at least to the Pleistocene (Jefferson, 1968). Isolated populations are known to exist as far into
the Mojave Desert as Afton Canyon, and in the Amargosa River, County of Los Angeles
(Lovitch, 1999). Truckee, Humboldt, and Carson Rivers in Nevada, Puget Sound, and the
Columbia Gorge historically supported disjunct populations (Lovitch, 1999). The elevational
range for the species is from brackish estuarine waters at sea level to over 2,000 meters, but it’s
uncommon over 1,529 meters (Stebbins, 1954; Bury, 1963; Holland, 1994).
Habitat Afinity
The southwestern pond turtle inhabits slow moving permanent or intermittent streams, small
ponds, small lakes, reservoirs, abandoned gravel pits, permanent and ephemeral shallow
wetlands, stock ponds, and sewage treatment lagoons (Rathbun et al., 1992; Holland, 1994).
Pools are the preferred habitat within streams (Bury, 1972). Abundant logs, rocks, submerged
vegetation, mud, undercut banks, and ledges are necessary habitat components for cover as well
as a water depth greater than 2 meters (Brattstrom and Messer, 1988; Holland, 1994).
Additionally, emergent basking sites, emergent vegetation and the availability of suitable
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 379 -
terrestrial shelter and nesting sites seem to characterize optimal habitat. Adjacent upland areas
typically provide, overwintering and estivation sites.
Life History
Pond turtles are omnivorous feeders with a broad feeding niche, but do not select food items on
general availability (Bury, 1986). It scavenges, but also takes live prey, acting as an
opportunistic predator. Adults ingest plants as part of their diet, which provides nutrients when
live prey are unobtainable, but tend to prefer live or dead animal food instead of plant material.
Many small animals such as fish, crustaceans, worms and insects abound in the filamentous algae
eaten by the pond turtle.
The southwestern pond turtle's daily activity revolves around thermoregulation and foraging
patterns. It often suns itself at the edge of water, or on branches or stones above water. It is
secretive and will seek refuge at the bottom of a pond or stream at the slightest disturbance.
Geographical variation occurs in the seasonal activity of the pond turtle, although in warmer
portions of its range, it may be active in every month (Holland, 1994). Courtship and mating
behaviors of the southwestern pond turtle have been observed from February through November
(Holland, 1988; Buskirk, 1991; Goodman, 1997a). Goodman (1997) found that females begin
laying eggs at a carapace length greater than 1 lcm, and Holland (1994) suggests an age of
approximately 6-7 years. Depending on latitude, the peak nesting season is from late May
through early July, but extends from late April through August (Holland, 1994).
If suitable nesting sites are not available, females have been observed to travel up to 1.2 miles
along a waterway to lay their eggs (Rathbun et al., 1992). Nests are typically located along
stream or pond margins, however, they may be located over 100 meters from water on hillsides.
Terrestrial nest locations (6) inspected by Rathbun et al. (1992) were all found in open, grassy
areas with a southern exposure. Holland (1994) reports that nesting forays onto land may require
several days.
Nest cavities were pear-shaped and measured 2.6-3.1 inches (6.5-8.0 cm) deep with a 2.6-2.8
inches (6.5-7.0 cm) wide egg chamber and a 1.4-1.6 inches (3.5-4.0 cm) mouth (Rathbun et al.
1992). Average clutch size (6.12; range 1-13) and possibly mean egg width is significantly
correlated with body size (Holland, 1994; Goodman, 1997). Portions of the female population
do not lay eggs every year. Incubation period varies with latitude, but is typically 80-126 days
(Goodman, 1997a; Holland, 1994). Lardie (1975) and Feldman (1982) incubated eggs at 77-91'
F and determined an incubation period of 73-8 1 days. Hatchlings did not leave the egg if the
temperature exceeded 8 1' F, but they emerged within 2-3 hours after moving the egg to a cooler
environment (Feldman 1982). Environmental sex determination occurs in pond turtles. At low
incubation temperatures, males are produced and females at high temperatures. Ewert et al.
(1994) found the pivotal temperature to be approximately 86' F.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Population Trend
- 380
In recent years, the southwestern California pond turtle population has experienced an alarming
decline. Between Ventura County and the Mexican border, known localities have decreased
from 87 in 1960, to 57 in 1970, and as of 1987, only 10 of 255 sites inspected were thought to
support reproductively viable populations (Brattstrom, 1988; Brattstrom and Messer, 1988;
Lovitch, 1999). Fifty-three of the 255 sites inspected contained pond turtles, the distribution of
these sites follows: 25 in Ventura County, 10 in Los Angeles County, eight in San Diego County,
four in Orange County, three in southwestern San Bernardino County, and three in western
Riverside County.
Threats
Destruction of suitable habitat appears to be the biggest threat to populations of the southwestern
pond turtle (Brattstrom, 1988; Brattstrom and Messer, 1988). Over 90 percent of wetland habitat
within its historic California range has been eliminated by agricultural development, flood
control, water diversion projects, and urbanization (US. Fish and Wildlife, 1992, 1993).
Additionally, predation on young by introduced aquatic species (e.g., bullfrogs, bass, and catfish)
collection for pets, urban-related predation pressures (e.g., dogs raccoons, skunks), competition
with non-native turtles (Holland, 199 I), contaminant spills, grazing, off-road vehicle use and
vehicle strikes on roads (Holland, 1994) have all contributed to the sharp decline this species has
experienced in recent decades. Dams and channelization have greatly reduced the availability of
suitable habitat (Brattstrom and Messer, 1988). Reese and Welsh (1988) determined that the
quality of southwestern pond turtle habitat has been reduced by alteration of channel morphology
and flow rates associated with dam construction. Invasion of exotic vegetation species such as
tamarisk (Tarnarix sp.) is another threat to the pond turtle. Establishment of tamarisk results in
changes to hydrology and channel morphology which degrades pond turtle habitat. Habitat
fragmentation is associated with these threats and results in a reduction of genetic variability.
The survival of the Oregon, Washington, and Mojave River populations may be significantly
threatened by loss of genetic variability. These populations display a high degree of genetic
similarity which reflects a lack of dispersal and gene flow and is probably a consequence of
habitat fragmentation (Lovitch, 1999). Gray (1995) reports a much higher genetic variability in
southern California populations.
Environmental Baseline
Within MHCP there are approximately 3,768 acres of potential habitat, of which approximately
708 acres are within the City (see footnote 2). Habitat includes freshwater, natural
floodchannel/streambed, and freshwater marsh aquatic vegetation communities, and all riparian
vegetation communities. Hibernating and nesting habitat in the adjacent uplands were not
quantified.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Within the MHCP, pond turtles have been observed in Escondido Creek, the San Luis Rey River,
and Buena Vista Lagoon. All three of these locations are considered major populations and
critical locations. Buena Vista Lagoon is the only documented observation of the southwestern
pond turtle occurring in the City. The size and extant of this population is unknown due to a lack
of survey effort. This subspecies is limited to freshwater ecosystems and can therefore only
disperse through suitable habitat corridors. There is limited connectivity potential from the
population’s current location. Based on habitat affinity, there is potential for this subspecies to
be present in other freshwater habitats.
381 -
Effects of the Action
Direct Eflects
The preserve design provides for conservation of 494 (86 percent) riparian, and 1252 acres (92
percent) marsh, with anticipated impacts to 80 acres (14 percent) riparian, and 114 acres (8
percent) marsh as a result of this plan. Direct impacts to this subspecies is unknown based on the
lack of defined freshwater habitat amounts within the Subarea. However, we anticipate few
direct impacts to this species based on the limited amount of freshwater habitat and the lack of
development proposed in this type of habitat.
Indirect Efects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse affects to southwestern pond turtles within the action area.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets,
and habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
Specifically, indirect effects to southwestern pond turtles may occur as result of degradation to
freshwater habitats. These impacts could include adverse changes in the hydrology or water
quality, impacts to riparian habitats, collection for pets, and predation by domestic animals.
Also, adverse edge effects resulting from increased human traffic may deter southwestern pond
turtles from nesting in the Subarea.
The Subarea plan does not provide specific conservation measures for this species; however, the
MHCP requires the following conditions be met for this species to be covered:
1. As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist must survey all areas of the property containing or
adjacent to suitable aquatic habitat (streams, ponds, riparian, and marsh areas) for this
species. Impacts proposed in natural upland vegetation that is contiguous with and
within 1,500 feet of potential aquatic habitats may affect turtle nests or hibernating
turtles. Consequently, whenever possible, potential suitable habitats within 1,500 feet of
the proposed impact area shall be surveyed, unless this adjoining habitat can be
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 382 -
demonstrated not to be appropriate for nesting or hibernating. Surveys shall be
conducted during the presumed active period (March through October) prior to any
proposed impact as part of the project review process (e.g., CEQA process) both within
and outside of the FPA. Any report of a pond turtle observed during the initial survey
shall require a follow-up intensive trapping study to determine if breeding is occurring.
Evidence of breeding shall include individuals representing multiple-year classes,
presence of adult male and female turtles, or nest locations.
Avoid and minimize impacts to critical breeding locations, including at Buena Vista
Lagoon, Escondido Creek, and the San Luis Rey River. Although western pond turtle is
not an MHCP Narrow Endemic, all currently known or future discovered populations
will be treated consistent with requirements of the Narrow Endemics Policy, including
the following: (a) maximum avoidance of impacts, to the degree feasible while
maintaining reasonable use of the property; (b) for unavoidable impacts, species-
specific mitigation designed to minimize adverse effects to species viability and to
contribute to species recovery; and (c) no more than 5 percent gross cumulative loss
inside the FPA or 20 percent gross cumulative loss outside the FPA.
Any identified pond turtle breeding area, including aquatic, riparian, marsh, and
associated uplands, shall be delineated and conserved. The breeding area shall be
conserved such that the full range of life activities can continue at an equivalent level,
preferably through avoidance/minimization of impacts to the site. Sufficient upland
nestinghibernating habitat shall be provided adjacent to occupied turtle habitat on a
case-by-case basis and shall require the written concurrence of the USFWS and CDFG
within 30 days of receipt of request for written concurrence from the local jurisdiction.
Projects having direct or indirect impacts to the southwestern pond turtle shall adhere to
the following measures to avoid or reduce impacts:
a. The removal of native vegetation and habitat shall be avoided and minimized to
the maximum extent practicable. Determination of adequate avoidance and
minimization of impacts shall be consistent with Sections 3.6 and 3.7 of the
MHCP plan. Deviations from these guidelines shall require written concurrence
of the USFWS and CDFG. For temporary impacts, the work site shall be
returned to preexisting contours and revegetated with appropriate native species.
All revegetation shall occur at the ratios specified in Section 4.3 of the MHCP
plan. All revegetation plans shall be prepared and implemented consistent with
Appendix C (Revegetation Guidelines) and shall require written concurrence of
the USFWS and CDFG. If written objections are not provided by the wildlife
agencies within 30 days of receipt of written request for concurrence by the local
jurisdiction, then the deviation may proceed as approved by the local agency.
The wildlife agencies shall provide written comments specifying wildlife agency
concerns.
Projects shall be implemented consistent with Appendix B (Standard Best
Management Practices).
Projects shall avoid or minimize placement of equipment and personnel within
the stream and adjacent natural habitats in known turtle locations.
2.
3.
4.
b.
c.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 383 -
d. If necessary and acceptable to the wildlife agencies, turtles shall be captured and
held in an approved facility until the site is restored and acceptable for
reintroduction.
Individuals found in areas that are deterrnined to be nonbreeding sites may be
relocated to unoccupied, appropriate breeding areas within the MHCP preserve.
e.
Known breeding populations and areas shall be included in the MHCP monitoring
protocol.
5.
As a result of the measures incorporated into the MHCP Subregional Plan, we anticipate few
indirect impacts to this species.
Conclusion
As described in the analyses above, we have determined that the MHCP Subregional Plan may
adversely affect the southwestern pond turtle. However, the plan assures that impacts to breeding
and upland habitat will be avoided, minimized and mitigated appropriately. After reviewing the
current status of this species and its critical habitat, the environmental baseline for the action
area, the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan is not likely to jeopardize the continued existence and
recovery of this species. In addition, the City’s lack of coverage for this species is not likely to
jeopardize the continued existence of this species because this species will benefit from the no
net loss of wetland standard and wetland buffer standards within the HMP.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Phrynosoma coronaturn blainvillei (San Diego horned lizard)
Status of the Species
- 384
Listing Status
Th San Diego homed lizard is considered a State Protected Species and a California Species of
Special Concern. This species is not Federally listed.
Species Description
Phrynosoma coronaturn blainvillei is a large (65-1 10 mm snout to ventral length), dorsoventrally
flattened lizard with five backwardly projecting head spines. There is a large shelf box above
each eye terminating in a backward projecting, spine-like scale. The dorsal color is highly
variable, but typically gray, tan, reddish-brown, or whitish, and usually resembles the prevailing
soil color (Jennings 1988). The venter is yellow to white with discrete, dark spots.
Distribution
Historically, the San Diego homed lizard was distributed from the Transverse Ranges in Kern,
Los Angeles, Santa Barbara, and Ventura counties southward through the Peninsular Ranges of
southern California to Baja California (Jennings, 1988). The San Diego homed lizard seems to
have disappeared from about 45 percent of its former range in southern California, in particular
on the coastal plain where it was once common (Hayes and Guyer, 198 1) and in riparian and
coastal sage scrub habitats on the old alluvial fans of the southern California coastal plain
(Bryant, 191 1, Van Denburgh, 1922).
Habitat Afinity
This species is found in a wide variety of vegetation types including coastal sage scrub, annual
grassland, chaparral, oak woodland (Klauber, 1939; Stebbins, 1954). In inland areas, this species
is restricted to areas with pockets of open microhabitat, created by disturbance (e.g., floods, fire,
roads, grazed areas, fire breaks) (Jennings and Hayes, 1994). The known elevation range of this
species is from 10 meters at the El Segundo dunes (Los Angeles County) to approximately 2,130
meters at Tahquitz Meadow, on San Jacinto Mountain, in Riverside County. The San Diego
homed lizard is thought to intergrade with P. c. frontale in extreme southern Kern county and
northern Santa Barbara, Ventura, and Los Angeles counties (Reeve, 1952; Montanucci, 1968;
Jennings, 1988).
Life History
Homed lizards of the genus Phrynosoma are primarily ant-eating reptiles whose dietary habits
are well known (Montanucci, 1981; Pianka and Parker, 1975; Powell and Russell, 1984; Rissing,
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
1981; Turner and Medica, 1982). Up to 90 percent of the diet of San Diego homed lizards
consists of native harvester ants (Pogonomymex spp.) (Pianka and Parker, 1975), and this
species dbes not appear to eat non-native Argentine ants (Jennings and Hayes, 1994) that have
replaced native ants in much of southern California (Ward, 1987). Other slow moving insects,
such as beetles, flies, and caterpillars are consumed opportunistically when encountered (Presch,
1969; Pianka and Parker, 1975).
385 -
The daily diurnal activity of the San Diego homed lizard is distinctive. As surface temperatures
reach greater than19 degrees Celsius (almost 15 degrees Celsius below temperatures of normal
activity), just prior to sunrise, this taxon emerges from burial sites in the substrate into a position
that allows them to bask in the first rays of the sun (Heath, 1965; Hagar, 1992). Heath (1962)
found that two distinct behavior patterns initiate daily activity; (1) the lizards “may move upward
in the sand until their heads are exposed and remain in this position until warmed to their activity
levels; (2) alternately, they emerge completely and begin basking in a fully exposed position.”
He also found a similarity in emergence times between two groups of P. coronatum and P.
comutum, suggesting the operation of an endogenous or circadian rhythm.
High site fidelity is often exhibited by San Diego homed lizards, as effective thermoregulation
(optimum: 29-39 degrees Celsius) requires familiarity with their surroundings (Heath, 1965).
Midday temperatures over 40°C are avoided as San Diego homed lizards bury themselves in the
substrate, reemerging in the later afternoon to resume full activities (e.g., feeding, territorial, and
reproductive).
Tollesturp’s (198 1) observations suggest that olfactory cues are important in Phrynosorna ’s daily
activities, including courtship, feeding, sex recognition, and conspecific interactions. In addition,
they were observed to apparently mark sites by partially extruding the cloaca and rubbing it back
and forth on the substrate.
Contrary to Heath (1962), Whitford and Bryant (1979) did not observe activity in P. comuturn
until approximately two hours after sunrise, and most feeding and other activity was confined to
the morning hours. Typical morning activity observed by Whitford and Bryant involved “sitting
for 30 seconds to several minutes, walking followed by elevated sitting, lasting from a few
seconds to several minutes, terminated by a feeding bout or further walking, then resumption of
elevated sitting.’’ They also found that a significant portion of the daily activity of P. comuturn
involves shrub climbing and movement in the shrub canopy. Through the middle part of the day,
the lizards positioned themselves in a shrub canopy where the ambient temps ranged from 35” C
to 40” C. Their feeding corresponded with the peak activity patterns of harvester ants, between
the hours of 0900 and 1100 (Whitford and Ettershank, 1975; Whitford, et. al., 1976). As
expected, the bulk of thermoregulatory basking occurred in the early morning and late afternoon.
In southern California, the male reproductive cycle begins during mid to late March and ends in
June as testes decrease in size. Testes become their maximum size during spring with
sperrninogenesis in progress (Goldberg, 1983). Female San Diego homed lizards are oviparous,
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 386
laying a clutch of 6-17 eggs between May and July each year (Stebbins, 1954; Howard, 1974;
Goldberg, 1983). Hatchlings appear in late July to early August, and require 2-3 years to reach
reproductive age (Stebbins, 1954; Howard, 1974; Pianka and Parker, 1975; GoIdberg, 1983).
-
After reviewing the data (Stebbins, 1954; Pianka and Parker, 1975; Howard, 1974), Goldberg
(1983) found a range of average clutch sizes from various studies ranging from 11-12.5
individuals. Goldberg (1983) also found that P. coronaturn has the potential to produce multiple
clutches during the Spring.
The defense that San Diego homed lizard most often uses against approaching predators is to
depend on their cryptic appearance and simply lie motionless (Jennings and Hayes, 1994).
Klauber (1939) documented change in body coloration to match the soil or sand on which they
were found. Other methods used include hissing, inflating lungs to increase apparent size (Pianka
and Parker, 1975; Munger, 1986; Sherbrooke, 1981), raising their horns by lowering their snout
(Pianka and Parker, 1975; Sherbrooke, 198l), squirting blood from the corner of the eye (which
seems to repel dogs and cats) (Presch, 1969; Pianka and Parker, 1975), tilting the body when
irritated (Milne and Milne, 1950; Smith, 1946; Tollestrup, 198l), presenting a bristling of scales
of the back while standing well up on the legs (Bryant, 191 l), and running a short distance before
flattening out or burrowing several centimeters under the ground (Presch, 1969). When P.
coronaturn flattens its body, it usually tucks its head down, exposing its horns, and often charges
the enemy (Winton, 1916). An additional defense mechanism may be based on learned
avoidance by predators suggested by reports of snakes dying while trying to swallow
Phrynosorna which are well documented in the literature (Klauber, 1972; Milne and Milne, 1950;
Van Denburgh, 1922; Vorhies, 1948; Wright and Wright, 1957).
Using a radiotelemetry study, Munger (1984) found that homed lizards utilize limited home
ranges, occupying areas much smaller than they would if they moved randomly. His data further
suggest that there is a reduction in home range overlap, and contrary to expectation, overlap
between sexes tended to be less than overlap between individuals of the same sex (Munger,
1984).
In Whitford and Bryant’s 1979 study, the closely related P. comutum moved an average of 46.8
meters per day (range = 9-91 m). They also found that an individual homed lizard moved over a
zigzag course during a day but rarely crossed its own trail. Munger (1986) found that male P.
comutum may have a 2.40 hectacre (5.9 acre) home range.
The San Diego homed lizard emerges from hibernation in March, and becomes surface active in
April through July, after which most adults estivate (summer hibemation) (Hagar, 1992). The
adults reappear again briefly in late summer and return to overwintering sites between August
and early October depending upon elevation (Klauber, 1939; Howard, 1974; Hagar, 1992).
Population Trend
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The total area once occupied in southern California has shrunk by approximately 45 percent
(Jennings and Hayes 1994). Most surviving populations inhabit upland sites with limited
optimal h’abitat. Many of these sites are on marginally suitable Forest Service land (Jennings and
Hayes, 1994). Limited information is available for this species populations in southern
California.
387 -
Threats
The specialized diet and habitat requirements, site fidelity, and cryptic defense behavior make
San Diego homed lizards highly vulnerable. Commercial collecting, and habitat loss due to
agriculture and urbanization are the main reasons cited for the decline of this taxa. However, the
most insidious threat to the San Diego homed lizard is the continued elimination of its food base
by exotic ants. Argentine ants colonize around disturbed soils associated with building
foundations, roads and landfills, and expand into adjacent areas, eliminating native ant colonies
(Ward, 1987). Under these conditions San Diego horned lizard populations have become
increasingly fragmented, and have undergone the added stress of a number of other factors,
including fire, grazing, off-road vehicles, domestic cats, and development (Jennings and Hayes,
1994). This taxon is unable to survive habitats altered by development, agriculture, off-road
vehicle use, or flood control structures (Goldberg, 1983).
Environmental Baseline
Documented San Diego horned lizard locations within the MHCP area include scattered
sightings in east Oceanside, Carlsbad, south Encinitas, southwest San Marcos, and southwest
Escondido (near Harmony Grove). There are 34 location points identified in the MHCP,
however, none are major or critical populations. There are over 24,000 acres of habitat, within
MHCP, that are of suitable type for the San Diego horned lizard, however, a substantial portion
of this acreage would not meet this species habitat affinities.
Observations have been reported in the City of Carlsbad at La Costa Parks, Carlsbad Oaks North,
and Calavera Hills. However, recent indirect effects from housing developments in these areas
has potentially resulted in significant adverse impacts to the populations through increased edge
effects and habitat removal. There is currently a minimal amount of habitat available for this
subspecies within the Subarea, however, there are a total 8,758 acres of habitat of the suitable
type Citywide. Only approximately 6,560 acres of existing habitat within the Subarea have the
potential to support San Diego homed lizards based on this species’ habitat affinities.
Database information suggests that populations of San Diego homed lizards outside of the
Subarea are much larger.
Effects of the Action
Direct Effects
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The MHCP requirse the following conditions be met in order for a City to receive coverage for
this specip:
1.
388 -
Conserve at least one additional habitat block within the study area that is large enough
(at least 400 acres), and low enough in edge effects and habitat degradation, to sustain a
viable population of homed lizards.
Institute an aggressive and proactive management and monitoring program designed to
control Argentine ants, maintain native ant species relied upon by homed lizards, and
translocate or reintroduce homed lizards into preserve areas from which it is extirpated
to maintain a functional metapopulation within the MHCP study area in perpetuity.
2.
In addition to meeting the above standards, the MHCP will conserve 65 percent of the known
location points and 14,521 acres of appropriate habitat types.
According to MHCP Volume 2, the City was estimated to conserve 2,659 acres (58 percent) of
potential habitat. This number is larger than that calculated by the HMP in Table 8 as updated by
addendum 2, however, it represents a smaller percentage of the estimated habitat within the city.
The preserve design for the City, according to the HMP, provides for conservation of 2,139 acres
(64 percent) of coastal sage scrub, 676 acres (70 percent) chaparral, 342 acres (85 percent)
southern maritime chaparral, 24 acres (86 percent) oak woodland, and 707 acres (38 percent)
grassland, with anticipated impacts to 1,176 acres (36 percent) coastal sage scrub, 292 acres (30
percent) chaparral, 50 acres (15 percent) southern maritime chaparral, and 5 acres (9 percent) oak
woodland, as a result of this plan. San Diego homed lizards may utilize portions of the above
mentioned habitats during their life history.
Anticipated direct effects to this subspecies will result from the elimination of 1,523 acres of
suitable habitat through the implementation of the Subarea plan. An unknown number of San
Diego homed lizards will be displaced or killed through this action. Direct impacts to San Diego
homed lizards may result from the allowance of activities in preserve areas, such as construction
and use of trail networks, roads, other recreational use areas, fire management techniques, and
landscaping of adjacent properties.
Indirect Efsects
Indirect impacts are anticipated with the implementation of the MHCP and Subarea plan, and
have the potential to cause adverse effects to San Diego homed lizards within the Subarea.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets,
and habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
Specifically, implementation of the MHCP and Subarea plan may indirectly affect this species by
increasing the amount of lighting. City lights are known to upset the behavior of snakes and
other nocturnal animals (Lieberman 2002) and may have adverse impacts to this subspecies near
developed areas.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Development will also increase the potential for introduction of Argentine ants by the creation of
edges. Argentine ants readily invade all mesic habitats (e.g., riparian areas) as well as more xeric
upland arkas within about 200 meters (656 feet) of irrigated landscapes. Therefore, smaller
fragmented habitats may leave little room for natural foraging behavior of this subspecies.
Considering a 5.9 acre home range (Munger 1986) with a 200 meter buffer surroundmg this area,
an individual would require approximately 46.4 acres for survival. The acreage necessary to
support a population of homed lizards is unknown due to a lack of scientific information. This
species is very susceptible to fragmentation resulting from urbanization and has experienced a
sharp decline as a result.
389 -
Other indirect effects to this subspecies may result from development and associated road
networks fragmenting portions of the San Diego homed lizard habitat inducing dispersal and
resulting in increased potential for road-kills. This species could also be impacted by collection
of the subspecies for pets.
Conclusion
As described in the analyses above, we have determined that the MHCP Subregional Plan may
adversely affect the San Diego homed lizard. However, the plan assures that impacts to breeding
and upland habitat will be avoided, minimized and mitigated appropriately. After reviewing the
current status of this species and its critical habitat, the environmental baseline for the action
area, the effects of the proposed action, and the cumulative effects, it is the Service’s biological
opinion that the MHCP Subregional Plan is not likely to jeopardize the continued existence of
this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize the
continued existence of this species because there are no critical or major populations in the
MHCP planning area, including the City, and the MHCP and City are conserving at least 58
percent of the species potential habitat. The City’s lack of coverage for this species will not
preclude the conditions of coverage being met by other MHCP participating cities.
389
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Aquila chrysaetos (Golden eagle)
-
Status of ihe Species
390
Listing Status
The golden eagle is federally protected under the Bald and Golden Eagle Protection Act (16
U.S.C. 5 668), and is considered a Species of Special Concern by the California Department of
Fish and Game. This species in not listed under the Act.
Species Description
Aquila chrysaetos is large eagle, 30-41 inches in length (76-104 cm) with a 76-92 inches
(2-2.4 m) wingspan. It is shaped like a hawk, but when soaring the wingspan is noticeably
greater. Adults are dark brown overall with a golden nape and wingtips that tend to be darker
brown. The underside of the tail may have a white base. Tails of adults are indistinctly banded
with grayish-brown and dark brown. As in other members of the genus Aquila, the tibiotarsi are
feathered. Immature A. chrysaetos appear similar in color to adults, but usually show a large
white patch at the base of the primaries (unlike the similar juvenile bald eagle [Haliaeetus
leucocephalus] which usually has white mottling on the underwing coverts) and a white tail with
a broad dark terminal band. Eyes are dark brown, and the bill is dark horn-colored and slightly
smaller than that of the bald eagle.
Distribution
The golden eagle has a holarctic distribution, extending as far south as north Africa, Arabia, and
the Himalayas in the Old World, and Mexico in America. It is a partial migrant within this
distribution, with the northern breeding birds migrating south in winter, while those of more
temperate climates remain all the year round (Brown and Amadon 1968). Golden eagles in
North America breed locally from northern Alaska eastward to Labrador southward to northern
Baja California, northern Mexico, and Maine. The species winters from southern Alaska and
southern Canada southward through the breeding range.
Within California the golden eagle is an uncommon permanent resident and migrant throughout
California, except center of Central Valley. It ranges from sea level up to 3833 meters (0-1 1,500
ft) (Grinnell and Miller 1944). Golden eagles are sparsely distributed throughout most of
California, occupying primarily mountain, grassland, and desert habitats. Approximately 500
breeding pairs are estimated to nest in California (Thelander 1974). They are mostly resident, but
may move downslope for the winter, or upslope after the breeding season. Some individuals
migrate into California for the winter (Zeiner, et al. 1990). The golden eagle population in San
Diego County is one of the best-studied populations in North America, with nesting pairs
monitored and documented nearly continuously since 1895.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 39 1
Habitat Afinities
Range-wide, golden eagles occur locally in open country (e.g., tundra, open coniferous forest,
desert, barren areas), especially in hills and mountainous regions (AOU 1998). Within southern
California, the species “favors grasslands, brushlands, deserts, oak savannas, open coniferous
forests, and montane valleys. It uses rolling foothills and mountain terrain, wide arid plateaus
deeply cut by streams and canyons, open mountain slopes, and cliffs and rock outcrops. Habitat
is typically rolling foothills, mountain areas, sage-juniper flats, and desert within its range in
California (Zeiner, et al. 1990). The species requires a large expanse for foraging and suitable
nest sites in the form of cliffs or large trees. Nesting is primarily restricted to rugged,
mountainous country (Garrett and Dunn 1981). Secluded cliffs with overhanging ledges and
large trees are used for cover (Zeiner, et al. 1990). Thus, the golden eagle uses a variety of
habitats: Golden eagles in San Diego County use cliffs or trees in rugged terrain for nesting, and
forage over plains, grasslands, or low and open shrublands (Scott 1985).
Golden eagles are typically not found in heavily forested areas or on the immediate coast and are
almost never detected in urbanized environments (e.g., Grinnell and Miller 1944; Garrett and
Dunn 1981). During the winter season, the golden eagle is found in shrub-steppe vegetation and
may use wetlands, river systems and estuaries in the coastal areas (Terres 1980).
Life History
The golden eagle is diurnal, spending most of the day (78 to 85 percent) perched and the rest of
the day in flight (Collopy and Edwards 1989).
The golden eagle eats mostly lagomorphs and rodents; it also takes other mammals, birds,
reptiles, and some carrion (Olendorff 1976). The diet is most varied in the non-breeding season.
The food supply for this species includes medium to large mammals and birds; a broad expanse
of open country is required for foraging (Johnsgard 1990). The golden eagle tends to be an
opportunistic forager, taking a combination of medium-sized vertebrate prey and carrion
(Olendorff 1976). They occasionally prey on domestic calves and lambs. Golden eagles may
compete with ferruginous hawks (Buteo regalis) for small mammals, and with California condors
(Gymnogyps califomianus) for carrion (Zeiner et al. 1990).
The species needs open terrain for hunting; grasslands, deserts, savannahs, and early successional
stages of forest and shrub habitats. It soars 30-90 meters (98-297 ft) above the ground in search
of prey, or makes low, quartering flights, often 7-8 meters (23-26 ft) above ground. Occasionally
it searches from a perch and flies directly to the prey (Carnie 1954). Sometimes it pirates food
from other predators. Hunting in pairs is apparently common, with one member of the pair
chasing the prey to exhaustion and the other swooping down to kill the prey (Terres 1980).
Foraging takes place over large areas of grassland and open chaparral or coastal sage scrub as
39 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 392
well. In parts of Idaho, eagles have been shown to select areas with abundant and large shrub
patches yhich are preferred by jackrabbits (Marzluff et al. 1997).
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Nesting is primarily restricted to rugged, mountainous country, with nesting occurring within
large trees or on cliffs (Garrett and Dunn 1981; Johnsgard 1990). Most of the nests are located on
cliffs with some nests occurring in Douglas-fir and others in pine trees (McGahan 1968).
Rugged, open habitats with canyons and escarpments are used most frequently for nesting. Pairs
may build more than one nest and attend them prior to laying eggs (McGahan 1968). It nests on
cliffs of all heights and in large trees in open areas (Call 1978). Nest locations tend to be more
closely associated with topographic heterogeneity than with a particular vegetation type. In San
Diego County, nests are frequently located on granite cliffs. Approximately 85 percent of all nest
areas overlook or are on the opposite side of the ridge from large valleys or areas of relatively
low topographic heterogeneity and open vegetation (Scott 1985). Alternative nest sites are
maintained, and old nests are reused. Each pair can have up to 10 nests, but only 2-3 are used in
rotation. Some pairs use the same nest each year, while others use alternate nests year after year,
and still others apparently may nest only every other year. The same nest may even be used by
succeeding generations of eagles (Terres 1980). The nest is a large platform, often 3 m (10 ft)
across and 1 m (3 ft) high, of sticks, twigs, and greenery. The breeding season extends from late
January through August, with a peak in March through July. The clutch size is 1-3, usually 2
(McGahan 1968). Eggs are laid in early February to mid-May. Incubation lasts 43-45 days
(Beebe 1974), and the nestling period usually is 65-70 days. The young birds hatch several days
apart, thus the older, stronger eaglets often kill their smaller siblings, and the parents do not
interfere (Terres, 1980). Parental care continues into August and family groups remain together
into November (Scott 1985).
After the young have fledged, they remain in the vicinity of the nest for about two weeks and
thereafter follow the parents away from the site (Brown and Amadon 1968). In some
populations, they are thought to be dependent on parental assistance for about three months after
learning to fly, and normally separate from the parents about October. The young often appear
near the nest site in the early part of the following breeding season, and immature golden eagles
sometimes frequent a nest site for several years before they finally breed there. The site then
used may be old or new or one that has been unoccupied for many years (Brown and Amadon
1968).
The breeding success of undisturbed pairs, as estimated by Brown and Amadon (1968), may vary
from 1.4 to 0.5 young per pair per year with an average of 1.4 in Montana. Where conditions
have been altered by man, the breeding success is lower, down to 0.4 or less. Golden eagles do
not reach reproductive age until about four years, and the average expectancy of life of adults in
the wild, assuming a 75 percent loss of young before maturity, is approximately ten years (Brown
and Amadon 1968). However, some eagles may live to at least 20 years (Brown and Amadon
1968, Harmata 2002).
Home range is probably the same as territory (Zeiner et al. 1990). Territory is estimated to
average 93 square kilometers (36 sq. mi) in southern California (Dixon 1937), and 124 square
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 393
kilometers (48 sq. mi) in northern California (Smith and Murphy 1973). Although total home
range can be very large, individuals tend to focus on a smaller core area within the total home
range (Mkzluff 1997). Golden eagles defend nest areas from conspecifics and appear to defend
part of their home range, however there can be substantial overlap between the home ranges of
adjacent pairs (Scott 1985).
-
Nesting areas are very sensitive to human encroachment and disturbance (Dave Bittner, pers.
comm.). Adults spent less time at nests and fed young less food less frequently when observers
camped 400 meters away than when observers camped 800 meters from nests (Steidl et al. 1993).
Although nest sites may benefit from the establishment of buffers to prevent human
encroachment, they have not been determined for this species (Newton 1979). Home ranges
adjoining developed sections of planning areas were shown to be abandoned more often than
interior areas, however, there is no distinct relationship between the proximity of nests to
development and their probability or year of abandonment (Scott 1985). The loss of nesting
areas could not be attributed to the loss of a specified amount of any vegetation type within 2.5
kilometers of nests. In addition, the loss of suitable foraging habitat around active nests was
equal to, or in some cases greater than, the loss around abandoned areas. In a study of golden
eagles in San Diego County, a significantly larger number of active eagle home ranges had no
human dwelling units within a radius of 1.6 kilometers, while a significantly larger number of
abandoned eagle home ranges contained 50 or more dwelling units within the same radius (Scott
1985).
Kochert, et al. (1999) studied the effects of fire on golden eagle reproductive success in Idaho
and found that in burned territories, golden eagles were significantly less successful in raising
young.
Population Trend
Long-term surveys show declines in nesting population in the western United States but not in
Alaska or Canada (Kochert and Steenhof 2002). Hoffman and Smith (in press) found increased
adult migratory movement and lower ratio of migrating juveniles to adults correlated with
cyclical declines in black-tailed jackrabbit (Lepus califomicus) populations. The golden eagle
was formerly considered common within suitable habitats in California (Grinnell and Miller
1944), the species was more recently judged to be uncommon throughout much of California
(Garrett and Dunn 1981). As suggested above, the golden eagle avoids settled areas and
therefore has almost certainly declined in the planning area, and in California as a whole, within
the past century due to loss of large unfragmented habitat areas (Grinnell and Miller 1944).
Threats
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 394
Threats to this species are human disturbance of nest areas, loss of habitat due to urbanization,
poaching, and collision with or electrocution from high tension wires (Remsen 1978). It may
desert its ;est in early incubation if disturbed by humans (Thelander 1974, David Bittner, pers.
comm.). In much of the western United States, golden eagle populations may be declining due to
conversion of native grasslands to cheatgrass (Brornus tectururn)-dominated grasslands (Steve
Hoffman, Jeff Smith, pers. comm.).
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Environmental Baseline
Eagle observations are scattered throughout the MHCP study area, however sightings are
becoming more rare due to habitat loss and fragmentation. Currently MHCP supports only one
nesting pair. Foraging habitat includes open sage scrub, grasslands, and recently burned
chaparral. Within the City of Carlsbad, this species has been observed near Buena Vista Lagoon,
in northeastern Carlsbad (Calavera Butte area), on the Tchang property in eastern Carlsbad, and
southeastern Carlsbad (Shelley property, John Martin US Fish and Wildlife Service, pers. obs.).
The Shelley property is approximately 7 kilometers from a known golden eagle nest location
(Bittner, unpubl. data).
The City contains 8,758 acres of undeveloped wildlife habitat, including 3,315 acres of coastal
sage scrub, 968 acres of chaparral, 392 acres of southern maritime chaparral, and 1,856 acres of
grassland, all of which may be used by foraging eagles.
Effects of the Action
Direct Eflects
No take of individuals or nests, including by harassment is allowed for this species. Overall, the
MHCP Subregional Plan will conserve approximately 5 1 percent of potential foraging habitats
(Coastal sage scrub and grasslands). Much of the habitat loss will occur in habitat fragments that
are no longer suitable for golden eagle foraging. The one extant nesting area, and most of that
pair’s core foraging area, will be conserved in the Del Dios area of Escondido.
Indirect Effects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to adversely affect golden eagles within the Subarea and the MHCP. These indirect
impacts include habitat fragmentation, edge effects including increased human disturbance, noise
effects, disruption of the natural fire regime, changes in hydrology from adjacent development,
increased lighting, and the proliferation of exotic species, as generally explained and applicable
in the “General Indirect Effects” section. General indirect effects may affect golden eagle
behavior, or abundance and diversity of their prey.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 395 -
The MHCP requires the following conditions be met by a City to receive coverage for this
species:
1. Maintain a 4,000-foot disturbance avoidance radius around any nest locations, including
currently used locations and any historically active nest locations that could be used
again in the future, as determined by species experts. Absolute buffers of less than
4,000 feet (but not less than 3,000 feet) may be allowed if topography effectively blocks
the line of sight between the nest location and any proposed human development, and
provided that the situation prevents any disturbance (including noise, artificial light,
recreational access, etc.) from being perceivable by eagles at the nest site, as determined
by species experts with experience monitoring golden eagle nesting pairs in San Diego
County (e.g., golden eagle researchers at the Wildlife Research Institute [WRI]).
Reserve lands within 4,000 feet of nesting locations (including current and historically
active locations), or within habitat areas identified as “primary foraging areas” by
golden eagle experts (e.g., WRI) must be managed to restrict any activities that could
disturb eagles during their normal nesting, loafing, foraging or other activities
(including hiking, mountain biking, or off-road vehicle use). Existing roads that allow
access within 4,000 feet of active nests will be closed to the public, including a dirt road
in the Del Dios area that passes near the currently occupied nest site.
No poisoning of ground squirrels or other wildlife, or other use of pesticides, will be
allowed within primary foraging areas or within 4,000 feet of known occupied or
historic nests within occupied territories.
2.
3.
Implementation of the above conditions is expected to reduce the potential for indirect effects
(primarily those due to human disturbance) to golden eagles.
Conclusion
The MHCP subregional plan will not result in any direct take of this species. However, the plan
can indirectly adversely affect this species, but the avoidance, minimization, and/or mitigation
measures included in the MHCP Subregional Plan will reduce the impacts to this species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the MHCP Subregional Plan is not likely to jeopardize the continued existence and recovery
of this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize
the continued existence of this species because no take of the species will occur and there are no
major or critical populations or critical foraging areas in the City.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 396
Campylorhynchus brunneicapillus couesi (Coastal cactus wren)
Status of ;he Species
Listing Status
The coastal cactus wren is listed as a State of California species of special concern. This species
is listed on the Federal Birds of Conservation Concern (2002).
Species Description
Campylorhynchus brunneicapillus couesi is a very large desert-dwelling wren (total length 18-22
cm, mass 32-47 kg). The upperparts are brownish with a distinct supercilium, white-streaked
back, and wings and tail heavily barred with black and white; underparts white becoming
cinnamon-buff on flanks and belly, and heavily spotted and streaked throughout with black
(Proudfoot et al. 2000). Sexes are alike. The bill is slightly shorter than the head, slender,
downcurved, pointed, and dark gray. The legs and feet are dark gray.
C. b. couesi may be difficult to distinguish between the other eight subspecies. The subspecies
are differentiated by plumage characteristics. The plumage of C. b. couesi is intermediate
between the peninsular birds and continental races. The underparts of the wings have heavier
spotting like peninsular birds, but underparts appear paler. The tail has more white banding than
continental birds; dorsal coloration is browner than anthonyi, but paler than bryanti.
Taxonomic affiliation of the populations in California have been under debate (Bancroft 1923,
Rea and Weaver 1990). Both a coastal and interior population exist in the state, historically
connected through the San Gorgonio Pass in Riverside County. (Rea and Weaver 1990). The
coastal population is unique in that it occurs exclusively within the Coastal Sage Scrub plant
community. The Checklist of North American Birds (American Ornithologists’ Union 1998)
currently recognizes all California populations of the cactus wren as Campylorhynchus
brunneicapillus couesi, inclusive of both the coastal and interior segments.
A portion of the coastal population, inhabiting southern Orange County, coastal San Diego
County, and extreme northwestern Baja California, was proposed for subspecies status in 1986,
and described as C.b. sandiegensis (Rea 1986). This designation was not accepted by the
American Ornithologists’ Union Committee on Classification and Nomenclature. It was
concluded that C.b. sandiegensis represents a intermediate form between C.b. couesi and C.b.
bryanti, a recognized subspecies found from San Diego County to northern Baja California,
Mexico (Department of the Interior 1994). The range of the C.b. couesi is separated from that of
C. b. bryanti by about 150 miles (Bancroft 1923).
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Distribution
- 397
This subspecies occurs in coastal sage scrub in southern Orange County to northwestern Baja
California. Coastal cactus wrens are found in two distinct regions in San Diego County. They
occur in the desert wash scrub and desert edge scrub in and near the Anza Borrego Desert (Unitt
1984). They also inhabit the coastal lowland, where they are restricted to coastal sage scrub
habitat with thickets of cholla cactus (Opuntia sp.) (Unitt 1984).
Habitat Affinity
Preferred habitat is dense coastal sage scrub 0.3-1.8 meters in height with patches of Opuntia.
Most nests are constructed between 1-2.5 meters above the ground surface and have been
observed as high as 5 meters above ground level. Coastal cactus wrens nest almost exclusively
in prickly pear (Opuntia littoralis and 0. oricola) and coastal cholla (0. prolifera). Coastal
cholla is the typical choice in southern San Diego County, where large prickly pears are scarce
(Rea and Weaver 1990).
Life History
The coastal cactus wren is predominately an insectivore foraging in vegetation and on the ground
for insects including caterpillars, moths, grasshoppers, spiders and an occasional reptile or
amphibian. They may also take fruit including those of cholla and elderberry (Sambucus sp.)
Cactus wrens establish resident territories and maintain them for life. Territories are utilized for
mating, nesting, brooding, and feeding and range in size from 0.5-2 hectares. Territorial defense
relaxes somewhat, and territories expand to 4-6 hectares in the non-breeding season (Anderson
and Anderson 1957).
Coastal cactus wrens will construct a nest which is a large, globular chamber with a tunnel-
shaped passageway and a perch near the entrance. Nest substrate is usually prickly pear or cholla
cactus. Two reports of nests found in yellow bush penstemon (Keckiella antirrhinoides) exist
from San Diego County (Rea and Weaver 1990). The spines of Opuntia deter numerous
predators from the nests cactus wrens construct. They build nests for both breeding and roosting.
The breeding season of the coastal cactus wren lasts between mid-March to mid-August. They
will generally lay 3-5 eggs per clutch. There is usually one, possibly two broods per season. The
incubation period lasts around 16 days. The nestlings will fledge from the nest approximately 21
'days posthatch and will begin to self-feed about 15 days after fledgling.
Cactus wrens in Arizona had an average life span of 1.3 - 2 years (Anderson and Anderson
1960). The oldest known bird was 6 years 4 months old (Gustafson and Hildebrand 1998).
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Population Trend
- 398
Coastal populations have been severely impacted by development throughout southern California
(Ogden Environmental and Energy Services 1992, Garret 1991). The decline of the coastal
segment of the cactus wren population in the region is indicative of the significant loss of the
Coastal Sage Scrub plant community. Based on information from historical accounts, the species
has been extirpated from several locations where it previously bred (Dawson 1923, Willet 1933,
Grinnel and Miller 1944). Dramatic declines have been documented in San Diego and Orange
Counties (Rea and Weaver 1990). Several of these populations described by Rea and Weaver
have been extirpated since the study was conducted (Eggert 1996). The popdation in the
Baldwin Hills, Los Angeles County, is declining and may be extirpated. (Garret pers. com [in
Solek and Szijj 19991).
Threats
Destruction of coastal sage scrub and maritime sage scrub habitat are the primary threats to the
coastal cactus wren. Urbanization and development are anticipated to continue to impact the
desired breeding, nesting, and foraging habitats of this species.
Increased fire frequency in coastal sage scrub kills the large cactus upon which cactus wrens
depend. Urbanization may increase ignition rates of fires in coastal sage scrub-dominated areas,
yet fires in urban areas are likely to be rapidly extinguished.
Domestic cats kill many adults in suburban areas in Arizona (Anderson and Anderson 1963,
1965). Snakes are known to depredate nests in California (Proudfoot et al. 2000).
In addition to exacerbating edge effects, habitat fragmentation by development can also affect the
species by limiting their connectivity to other populations of coastal cactus wrens. Most coastal
populations are now isolated due to urbanization of the region and persist in highly fragmented
habitats. Empirical data on the effects of habitat fragmentation specifically on cactus wrens are
limited. Isolated populations of birds in Coastal Sage Scrub have been shown to have high rates
of extinction (Soule et aE 1988), and cactus wrens may have difficulty in crossing urbanized areas
to repopulate remnant parcels of suitable habitat. Population viability analyses suggest that the
small size of these subpopulations coupled with habitat fragmentation may increase genetic
homozygosity and constrain the long-term viability of the metapopulation (Ogden Environmental
and Energy Services 1992). Unitt (1984) states that few of the remaining localities still
supporting cactus wrens can be considered safe from residential development.
Environmental Baseline
Within the MHCP planning area, a major population and critical location occurs in San Pasqual
Valley and extends west along the slopes above Lake Hodges in Escondido. Another isolated
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 399 -
observation site, on the north shore of Batiquitos Lagoon, is no longer extant. Suitable habitat is
limited in the MHCP area due to the lack of stands of tall cactus within the remaining coastal
sage scru6 habitat. The area of suitable habitat in Escondido along San Pasqual Valley and Lake
Hodges is large enough to support a substantial number of cactus wren pairs. The species has
been documented near the slopes on the north side of Batiquitos Lagoon in southwestern
Carlsbad.
Effects of the Action
Direct Eflects
The MHCP requires the following conditions be met for a City to receive coverage for this
species:
1. Ensure conservation of critical cactus wren locations near the San Pasqual Valley
consistent with the Narrow Endemic and Critical Location policies including: (a)
maximum avoidance of impacts, to the degree feasible while maintaining reasonable
use of the property; (b) for unavoidable impacts, implement species-specific mitigation
designed to minimize adverse effects to species viability and to contribute to species
recovery; and (c) allow no more than 5 percent gross cumulative loss of cactus wren
habitat and population size inside the FPA or 20 percent gross cumulative loss outside
the FPA.
Initiate a cactus wren habitat enhancementlcreation program in disturbed habitat areas
adjacent to conserved coastal cactus wren-occupied habitat. Mitigation for any take
within occupied cactus wren habitat must include habitat creation at a minimum 2: 1
ratio, by planting or transplanting of appropriate native cactus in areas of suitable soils,
vegetation, and topography (especially on south and west-facing slopes). Preference
should be for expanding existing habitat areas or adding satellite areas in close
proximity to existing occupied habitats.
Implement a fire management program to minimize and control wildfires that may
destroy large cactus within suitable habitat areas. In the event of a fire or other event
that kills or reduces vigor of cactus in existing habitats, adaptive management shall
include planting or transplanting of large cactus into these or other nearby areas to
offset the reduction in habitat value.
Prohibit development or other human disturbance adjacent to occupied habitat and
maintain a minimum 300-foot biological buffer around nests to the degree feasible.
Prohibit activity within occupied habitat from February 15 through August 15.
2.
3.
4.
The MHCP narrow endemic policy requires that cactus wren locations and suitable habitat are 95
percent to 100 percent conserved inside the FPA, and 80 percent conserved outside the FPA All
34 point localities are within the FPA. These points correspond with the only major populations
and critical habitat locations in the MHCP and occur primarily on south-facing slopes on the
north side of the San Pasqual Valley. The habitat in these critical locations is partially within
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
softline areas (75 percent conservation) and partially in hardline areas (100 percent conservation).
Therefore, according to the narrow endemic policy, all patness and habitat here are assumed to be
conserved at 95 to 100 percent.
400 -
The point location indicated in the Service’s GIS database within the City is outside the preserve,
and would be presumed impacted. However, the point is not within typical cactus wren habitat,
and should be considered anomalous. Nearly all of the potential cactus wren habitat (coastal sage
scrub with tall cholla) on the slopes north of Batiquitos Lagoon is included in the preserve.
Indirect Eflects
Indirect impacts are anticipated and have the potential to cause significant adverse effects to
coastal cactus wrens within the MHCP area. These indirect impacts include night lighting,
human disturbance, depredation by domestic pets, and habitat degradation, as generally explained
and applicable in the “General Indirect Effects” section.
Development associated with the plan is likely to result in an increase in the number of domestic
cats in the plan area. Domestic cats have the potential to kill individual coastal cactus wrens and
reduce populations. Anderson and Anderson (1963, 1965) found that domestic cats killed many
adult cactus wrens in suburban areas in Arizona. Crooks and Soule (1999) found that habitat
fragments surrounded by approximately 100 residences in southern California were used by
approximately 35 hunting, outdoor cats, and that these cats may kill an estimated 500 native birds
per year.
Conclusion
We anticipate the MHCP Subregional Plan will directly and indirectly affect this species as
described in the analyses above. However, the narrow endemic and critical location policy will
avoid at least 95 percent of the known locations and the avoidance, minimization, and/or
mitigation measures included in the MHCP Subregional Plan will reduce the impacts to any new
locations and the remaining 5 percent in the critical location. Additionally, this species will
benefit from the establishment and preservation in perpetuity of a system of interconnected
blocks of habitat in the MHCP planning area. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which will further reduce the indirect effects
and benefit the species. After reviewing the current status of this species, the environmental
baseline for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the action, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because no take of the known
species locations within the City are expected to .occur due to the FPA and wetlands no net loss
and buffer policy. There are also no major or critical populations of this species in the City.
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40 1
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Sialia rnexicana (Western bluebird)
- 402
Status of the SDecies
Listing Status
The western bluebird is not listed as threatened or endangered by the federal or state government.
Species Description
Sialia rnexicana is a small thrush (6.5-7.5 inches in length, 24-31g in weight). Adult males have
a bright, deep cobalt-blue head and upperparts with a chestnut breast and grayish underparts
(Guinan et al. 2000). They frequently have a chestnut patch on the back as well. Adult females
are dull in comparison with mild bluish coloration, suffused with dull rusty-brown. Juveniles are
grayish brown above with a rusty colored breast, both with white streaks. They have blue in the
wings and tail and a white eye ring. The bill is short, slender and dark gray. The legs and feet
are dark gray.
Distribution
The breeding range of the western bluebird is from southern British Columbia to northern Baja
California and the Central Volcanic Belt of the Mexico (Guinan et al. 2000). The western
bluebird is a common to very common winter visitor and will occur throughout the year in the
foothills and mountain zones of San Diego County (Unitt 1984). The wintering range is
predominately located within the breeding range (typically at lower elevations).
Habitat Afinity
The western bluebird is a bird of edge habitats. The species’ habitat requirements combine the
need for trees supplying lookout perches and nest holes with open country for foraging (Unitt
1984). This may include parklands that have trees with lawns or other open areas. Open
coniferous, wooded riparian areas, moderately logged forests and farmlands are the preferred
habitats of this species. In southern California this species breeds primarily in open oak
woodlands and coniferous forests; they are rarely found in large agricultural areas or desert
during breeding season (Garret and Dunn 198 1). Western bluebirds may also use sycamore-
dominated riparian habitat, in conjunction with open foraging areas. Disturbed areas (partially
logged or burned) may be occupied by this species, as long as there is an overstory and sufficient
nest sites.
Life History
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 403
Western bluebirds are medium-to short-distance partial migrant, but the least migratory of the
three bluebird species (Dunn 1981). Western bluebirds are insectivorous during the warmer
months and consume predominately berries during the non-breeding season. Wintering
individuals are especially abundant in years and in areas when mistletoe and juniper berry crops
are plentiful (Guinan et al. 2000).
-
This species has a socially monogamous relationship, in that single male and female form basic
social breeding territory. Some females will produce offspring outside of pair bond. The pair
bonds can be long (lasting 7 years or more). Pairs are formed between mid-February to mid-
April and nest building usually begins mid-March. Nests are created in cavities of trees, with
preference to coniferous and deciduous species. Eggs are laid locally in late April to early May.
The clutch size is 4-6 with approximately 2 broods per year. During the incubation period, which
can last 2 weeks, the male western bluebird will feed the female while she incubates. The female
does the brooding alone, while the male occasionally delivers food. Cooperative breeding does
occur in this species, with helpers being reported 7.4 percent of the time in California (Guinan et
al. 2000). Fledglings will depart from the nest in approximately 21 days.
Population Trend
Based on data from BBS routes (Sauer et al. 1999), long-term (1966-1994) trends show declines
in California and Arizona; the regional trends are generally non-significant declines, Small
sample sizes preclude detailed analyses of the trends during 1966-1979. The 1980-1994 trends
are similar to the long-term results, but include a decline in the survey-wide population. The
trend map indicates that declines are centered in California and Arizona, but also occur
throughout most of its range. Increasing populations are most prevalent in portions of Colorado,
New Mexico, and Utah. The survey-wide indices show periodic increases followed by declines,
generally in 4-5 year cycles. Whether or not these cyclical fluctuations are real or an artifact of
the BBS coverage in the western states is unknown. The overall trends are fairly stable.
However, the California population has declined throughout the survey period. Data from this
state comprises nearly one-half of all BBS data for western bluebirds, and has a large influence
on the regional population trend estimates.
Threats
Habitat loss as a result of extensive logging, development, natural and artificial fires, grazing,
and urbanization is likely the most important factor in declines in western bluebird populations.
Introduction of competitor species such as the house sparrow and European starling have also
been a factor in the decline of the western bluebird.
Environmental Baseline
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The western bluebird is primarily a wintering species in the MHCP planning area, except for
limited breeding in oak woodlands of Escondido and San Marcos. There are no major
populatio& or &tical locations in the plan area. There are only four known occurrences of the
species in the MHCP planning area.
404 -
The City includes 29 acres of oak woodland. Although the ecotone between oak woodland and
grasslands is considered the primary breeding habitat for this species, oak woodlands alone are
used to quantify the level of bluebird habitat conservation. In addition to oak woodland,
Carlsbad includes southern coast live oak woodIand and southern coast live oak riparian forest.
Major areas of oak-dominated habitat in Carlsbad are found in standards areas of Zone 15, Holly
Springs, and standards areas of Zone 21. Other areas of oak-dominated vegetation are included
in already-permitted projects. The MHCP area includes approximately 886 acres of oak
woodland, with the vast majority (approximately 655 acres) in Escondido. In addition, western
bluebirds may use sycamore-dominated riparian habitats (see below). The amount of sycamore-
dominated riparian habitat in the subarea and subregion is unquantified.
Information on the status of this species within the Subarea is limited. Unitt (1984) describes the
western bluebird is a “common to very common resident and winter visitor” in appropriate
habitats (see above) in San Diego County. However, due to the limited amount of appropriate
habitat within the Subarea, and area requirements of breeding bluebirds, we anticipate that this
species is a winter visitor and rare breeder within the Subarea. On April 10,2002, a pair of
western bluebirds were sighted in the sycamore-dominated riparian habitat in the “panhandle” of
Robertson Ranch (John Martin, USFWS, pers. obs.). Western bluebirds have been documented
at Buena Vista Lagoon and at Rancho Verde (Service GIS database). However, the birds at
Rancho Verde were seen in October 1991, and are therefore probably winter visitors. Breeding
status of the bluebirds at Buena Vista Lagoon is unknown.
,
Effects of the action
Direct Eflects
In order for a City to receive coverage for this species, the MHCP requires the following:
Minimize loss of oak woodland- grassland ecotone habitat and retain dead oak trees or branches
that provide nesting cavities in reserve areas. Monitor and control, as necessary, exotic bird
species that compete for nesting cavities (e.g., European starling and house sparrow). Monitor
nest boxes and install starling excluding devices as needed.
The MHCP will conserve 79 percent of the oak woodland ecological community which will
benefit this species. Although the ecotone between oak woodland and grasslands is considered
the primary breeding habitat for this species, oak woodlands alone are used to quantify the level
of bluebird habitat conservation. Three of the four known species points in MHCP are in areas to
be conserved.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Of the 29 acres of oak woodland habitats supporting or potentially supporting western bluebirds
in Carlsbad, approximately 16 acres (55 percent) are located within the preserve. An additional 8
acres are projected to be preserved in standards areas. Therefore, approximately 5 acres (17
percent) of oak woodland habitat may be impacted. Only one of the location points documented
in the HMP area is proposed for conservation. Oak woodland on Holly Springs, and the coastal
sage scrub that it is juxtaposed with, is included in the preserve. Standards for Zone 15 include
conservation of all riparian habitat. Planning standards for Zone 21 include avoidance of impact
to oak riparian forest. Therefore these areas of oak-dominated habitat within Carlsbad will be
preserved.
405 -
To ensure conservation of western bluebirds, it is important to conserve not only appropriate
nesting habitat, but nearby open areas for foraging. For example, though the sycamore-
dominated area of Robertson Ranch will be preserved, the western bluebirds are likely to
discontinue use of the area if the agricultural lands to the east and west are replaced with
development and southern willow scrub, respectively, because open areas for foraging will no
longer be present. To conserve western bluebirds in standards areas, nesting and foraging habitat
must preserved in juxtaposition,
Indirect Effects
Indirect impacts are anticipated with the implementation of the MHCP Subregional Plan and the
City’s Subarea plan, and have the potential to adversely effect western bluebirds. These indirect
impacts include habitat fragmentation, edge effects, noise effects, disruption of the natural fire
regime, changes in hydrology from adjacent development, increased lighting, and the
proliferation of exotic species, as generally explained and applicable in the “General Indirect
Effects” section.
Conclusion
We anticipate the MHCP Subregional Plan will directly and indirectly impact this species as
described in the analyses above. However, direct effects will be minimized by preserving 79
percent of the species predominant habitat type and the indirect effects will be minimized by the
measures included in the MHCP Subregional Plan. The MHCP Preserve will also be adaptively
managed, per the measures included in the MHCP Subregional Plan, which will further reduce
the indirect effects and benefit the species. After reviewing the current status of this species, the
environmental baseline for the action area, the effects of the proposed action, and the cumulative
effects, it is the Service’s biological opinion that the action, as proposed, is not likely to
jeopardize the continued existence and recovery of this species. In addition, the City’s lack of
coverage for this species is not likely to jeopardize the continued existence of this species
because the City will be preserving 79 percent of this species predominant habitat type and there
are no major or critical populations in the City.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) -
406
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Amphispiza belli belli (Bell’s sage sparrow)
- 407
Listing Status
The Bell’s sage sparrow is not a federally listed species. However, the State of California
Department of Fish and Game considers it a Species of Special Concern.
Species Description
The Bell’s sage sparrow is a medium sized sparrow and is sexually monomorphic (Martin and
Carlson 1998). Upperparts are generally brownish-gray from the culmen to the undertail coverts,
with distinct dark streaking on the back. Wings are more brownish, with pale feather edges.
Underparts are whitish from the chin to the undertail coverts, except for a blackish central breast
spot, and diffuse brownish streakmg on the sides of the breast, sides, and flanks. One white spot
is located in front of each eye. A thin white eye ring and dark submoustachial stripe make up the
rest of the distinguishing characteristics of the head. There is a yellow patch located on the
underside of the wings located at the “wrist” (Martin 1998). The tail is blackish brown, of
medium length, and slightly notched. The bill is gray, short, and somewhat conical. The legs
and feet are dull pinkish-gray.
Distribution
Bell’s sage sparrows range from the Cascade Mountains to Baja California, Mexico, but are
locally uncommon in coastal sage scrub and open chaparral in San Diego County (Johnson and
Marten 1992). Documented Bell’s sage sparrow locations include north and southeast Carlsbad,
east Encinitas, north and south San Marcos, and south Escondido.
Habitat Afinity
Bell’s sage sparrow habitat includes dense coastal sage scrub and open chaparral, particularly in
large, unfragmented blocks in inland areas. Dense stands in sunny, dry areas are preferred habitat
(Unitt 1984). Bolger et al. (1997)’ and Grinnell and Miller (1944) found that Bell’s sage sparrow
was strongly associated with chamise chaparral. This species is patchily distributed, and is
absent from many tracts of apparently suitable habitat.
Life History
The Bell’s sage sparrow is a year-round resident of southern California. It may move further
down the slope of its habitat during the winter months (Martin 1998). It appears to be sedentary,
but apparently wanders occasionally, since two were seen at Point Loma, a locality where this
race does not breed (Unitt 1984).
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
It is generally a ground-foraging omnivore during breeding months and a ground-gleaning
granivore,during non-breeding months (Martin 1998). Insects, spiders, seeds, small fruits and
vegetation are the primary foods (Martin 1998).
408 -
The nest is a small open-cup consisting of small twigs and grasses, commonly located in a shrub
near the ground or in grass on the ground. The clutch size is between 3-4 eggs and there can be
up to 2 broods. Incubation lasts between 10 to16 days and fledging occurs in 9 to 11 days.
Population Trend
Breeding densities have been measured in unburned coastal sage scrub near Perris, Riverside
County, resulting in 94 to 11 l/km’ and 6 to 39/km2 in first-year burned areas (Martin 1998). In
California, BBS analysis of 52 routes shows no significant trend for sage sparrow between 1966
and 2000. However, analysis of Bell’s sage sparrow (rather than all California subspecies of A.
bellii) population trend requires restricting analysis to individual regions in California. There is
too little region-specific BBS data available (4-12 routes per region) to reliably estimate trends
(Sauer et al. 2003).
Threats
Bell’s sage sparrow is vulnerable to loss, degradation, and fragmentation of coastal sage scrub
habitat. This species appears especially sensitive to habitat fragmentation (Bolger et al. 1997).
Unitt (2003) reports “no records of the Sage Sparrow from isolated canyons enclosed within the
city of San Diego.” In a study of bird abundance and diversity in isolated habitat patches in an
urban matrix in San Diego, no Bell’s sage sparrows were encountered (Clark Winchell, US Fish
and Wildlife Service, unpubl. data). Lovio (1996) found Bell’s sage sparrow to be the most
sensitive to habitat fragmentation of 3 1 nesting species studied in southwestern San Diego
County. The smallest fragment of habitat in which he found the species was 160 hectares (about
400 acres). Bolger et al. (1997) found that Bell’s sage sparrow was significantly less likely to
occur near an urbadhabitat interface than in the interior of a patch of habitat.
Environmental Baseline
Bell’s sage sparrow habitat includes dense coastal sage scrub and open chaparral, particularly in
large, unfragmented blocks in inland areas. There are no major populations or critical locations
in the MHCP planning area. Within the MHCP area, the species has been documented in
northeastern Carlsbad (Calavera Butte area, one point location) and southeastern Carlsbad
(Villages of La Costa, four point locations), east Encinitas, north and south San Marcos, and
south Escondido.Biologists managing the Calavera Preserve in northeastern Carlsbad, near one
of the historic point locations on the Service’s GIs database, since 1996, have not encountered
Bell’s sage sparrow (John Burke, The Environmental Trust, pers. comm.).
408
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Approximately 3,315 acres of coastal sage scrub, 968 acres of chaparral, and 362 acres of
southern maritime chaparral exist in the City. However, only four large expanses (which may be
necessary for this fragmentation-sensitive species to persist) of sage scrub or chaparral habitats
occur in the City: Calavera Butte area, the Tchang property and DawsodLos Monos preserve,
Villages of La Costa, and Green Valley. Given the paucity of recent records of occurrence of this
species in Carlsbad, the limited availability of optimal habitat (chamise chaparral), its
fragmentation sensitivity, and the amount of recent development in the City, it is possible that the
species has already been extirpated from the City, or that the landscape has been modified
already such that the Bell’s sage sparrow is unlikely to persist within Carlsbad. However, if it
has not been extirpated from Carlsbad, the small numbers of Bell’s sage sparrows remaining in
the City are unlikely to be important to persistence of the species throughout its range, or in the
MHCP area.
409 -
Effects of the Action
Direct Efiects
The MHCP has the following condition for coverage of this species for a City to receive
coverage: Manage reserve areas to restrict activities that degrade Bell’s sage sparrow habitat,
including habitat alteration, spraying of pesticides, brown-headed cowbird parasitism, and
introduction of predators (e.g., domestic dogs and cats). Restrict human access to areas known to
support relatively large concentrations of sage sparrow during the breeding season (February 15
to August 3 1).
The FPA includes 8 of 10 point localities. Thus, only 20 percent will be impacted. The MHCP
will conserve 5,580 acres (61 percent) of suitable habitat for this species.
Of the 5 point locations in the Service’s GIs database for the City, 3 are located outside the
preserve and would be presumed impacted. However, the City will be preserving 65 percent of
coastal sage scrub and coastal sage scrubkhaparral mix vegetation communities which will
benefit this species.
Indirect Eflects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse effects to Bell’s sage sparrows within the Subarea. These
indirect impacts include night lighting, human disturbance, depredation by domestic pets, and
habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
The plan would allow development of the Holly Springs property, on the southern portion of the
relatively large expanse of coastal sage scrub and chaparral in the northeast portion of Carlsbad.
409
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Bell’s sage sparrow has been recorded in this area. In addition to the direct loss of habitat,
development of Holly Springs would reduce the size of the size of the remaining habitat patch,
and increke the ratio of habitat edge to area, reducing the probability that a Bell’s sage sparrow
population would persist in the remaining habitat fragment.
410 -
Conc 1 usi on
We anticipate the proposed action may directly and indirectly affect this species as described in
the analyses above. However, this species will benefit from the interconnected preserve that will
be established and preserved in perpetuity. This Preserve will be adaptively managed, per the
measures included in the MHCP Subregional Plan, which may further reduce the indirect effects
and benefit the species. After reviewing the current status of this species, the environmental
baseline for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the action, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because there are no major or
critical populations of this species in the City and the City will be preserving 65 percent of the
coastal sage scrub and coastal sage scrubkhaparral mix in the City.
410
Carlsbad Subarea Plan Biological and Conference Opinions (EWS-SDG-847.4)
Stephens’ Kangaroo Rat (Dipodomys sfephensi)
Listing Status
- 411
The Stephens’ kangaroo rat was federally listed at endangered throughout its range in 1988 (53
FR 38465). No critical habitat has been designated for this species. The species was listed as
threatened by the state of California in 1971.
Description and Identification
The Stephens’ kangaroo rat is 1 of 21 species of kangaroo rats (genus Dipodomys) that comprise
a distinct group of rodents belonging to the family Heteromyidae, suborder Sciuromorpha
(Williams et al. 1993). The family Heteromyidae occurs only in the New World, and the genus
Dipodumys occurs only in the more arid portions of the North American continent (Schmidly ef
al. 1993). Characteristics common to all kangaroo rats include external fur-lined cheek pouches,
large hind legs, relatively small front legs, long tails, and large heads (Williams et al. 1993).
The Stephens’ kangaroo rat is medium size for the genus and the average adult weight is
approximately 70 grams (2 ounces) while the total adult body-plus-tail length ranges between 23
and 30 centimeters (9 and 12 inches). The tail is 1.45 times the length of head and body (Bleich
1977). The length of the hind foot is between 3.8 and 4.3 centimeters (1.5 and 1.7 inches), and
length of ear (from notch) is between 1.3 and 1.5 centimeters (0.5 and 0.6 inches) (Bleich 1977).
The Stephens’ kangaroo rat is similar in coloration to the Pacific kangaroo rat (Dipodomys
agilis) but is paler, and can be distinguished from the latter, by its smaller ear and broader skull
(Grinnel 1922).
Habitat Affinities
Today, Stephens’ kangaroo rat is found almost exclusively in open, often disturbed, nonnative
grasslands or in sparse shrublands with areal cover of approximately less than 30 percent (Hogan
1981). Occupied habitats are usually described as sparse, slightly disturbed coastal sage scrub or
annual grassland. The actual distribution of suitable habitat is normally mixed with other habitat
types in a natural mosaic. The populations with the highest densities have been found in areas
where the herbaceous layer still contains California native annuals, and where perennial cover is
less than 30 percent (Hogan 1981). The Stephens’ kangaroo rat is most commonly associated
with Artemisia califomica and Eriogunum fasciculatum because these shrubs are often the most
obvious elements of the habitat. The animal is actually using the herbaceous layer which is often
dominated by filaree (Erodium cicutarium). Many areas supporting the species are shrubless
(O’Farrell, 1988 pers. comm.). Stephens’ kangaroo rat has been found on 36 types of well-
drained soils, and more than 125 soils are thought to be potentially suitable for the species.
Potentially suitable soils include those types capable of supporting annual grasses mixed with
forbs and shrub species. Additionally, soils must exhibit compaction characteristics suitable for
41 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 412
the establishment of burrows. Soils not considered suitable for Stephens’ kangaroo rat include
heavily alkaline or clay soils (generally in floodplains), highly rocky soils, shallow soils less than
50 centimeters deep, soils in areas exceeding 25 percent slope. It is generally restricted to areas
below approximately 3,000 feet in elevation. Stephens’ kangaroo rat movement is impeded in
densely vegetated areas, including areas with matted perennial grasses. This species will create
its own burrow system in areas with sandy soils and use existing burrow systems of gophers and
ground squirrels in areas of compacted soils.
-
Life History
Stephens’ kangaroo rat feeds on green vegetation, seeds, and, to a limited extent, insects. The
spring growing season and increased availability of food may coincide with the reproductive
peak of Stephens’ kangaroo rat. Breeding season has been speculated to occur between April and
June with a litter of 2-3 by late spring. The animals emerge from burrows at night to forage in
areas around the burrow, and return to the burrow to store food gathered into cheek pouches
(California Department of Fish and Game 2000).
Population Dvnarnics
Population studies indicate seasonal and annual variations in the number of animals occupying a
given area. These variations have been linked to the amount of rainfall and subsequent seed
production. A positive linear relationship exists between precipitation and population levels of
Stephens’ kangaroo rat. Observations of Stephens’ kangaroo rat populations by Price and Endo
(1989) at locations separated by approximately 12 miles, indicate that populations in western
Riverside County can show more than a tenfold temporal density fluctuations in response to
regional rainfall patterns.
The patchy distribution of Stephens’ kangaroo rat appears to depend on soil type, vegetative
stage, and slope (O’Farrell and Uptain 1989). These authors hypothesized that the species is
adapted for existence in intermediate vegetative seral stages. Areas disturbed by farming and
subsequently allowed to go fallow allow invasion by weedy species and rodents such as the
Botta’s pocket gopher (Thornomys umbn’nus), that facilitate colonization of the area by the
Stephens’ kangaroo rat, who can use the burrows. Apparently, absent some process that
maintains relatively open grass or forb lands, eventual succession or maturation of vegetative
communities renders habitat unsuitable for the Stephens’ kangaroo rat.
Status and Distribution
The historic and current geographic distribution of the Stephens’ kangaroo rat coincides with the
inland valleys of the coastal side of the Peninsular Ranges of San Bernardino, Riverside, and San
Diego counties of southern California (Grinnell 1922, Lackey 1967a, Hall 1981, Bleich 1973,
Bleich and Schwartz 1974, O’Farrell and Uptain 1989, Dudek & Associates 1998, Ogden
412
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Environmental and Energy Services Co., Inc. 1998). The entire geographic range of the Stephens’
kangaroo rat was estimated to be approximately 2,870 square lulometers or 287,000 hectares (ha)
(1,108 sqkare miles) at the time of its listing in 1987 (U. S. Fish and Wildlife Service 1987). The
range of the Stephens’ kangaroo rat has been refined since the listing of this animal through the
discovery of populations in the general vicinities of Norco and Anza in Riverside County, and
Guejito Ranch and Ramona in San Diego County. Based on a review of available information,
the range is now estimated to be approximately 5,053 square kilometers (1,951 square miles)
(U.S. Fish and Wildlife Service unpubl. GIS data 1998). Specific populations occur at Camp
Pendleton Marine Corps Base, the adjacent Fallbrook Naval Weapons Station, around Lake
Henshawwarner Springs, and the Guejito and Santa Maria Valleys.
413 -
Reported densities of Stephens’ kangaroo rats range from 3 to 23.7 individuals per acre during
the summer months (Bleich 1973, Thomas 1975). Fall and winter densities range from 2 to 6
individuals per acre (Price and Endo 1989). According to O’Farrell and Uptain (1989), most of
the currently occupied habitat contains populations of low (less than 2 individuals per acre) or
medium density (2 to 4 individuals per acre), and only a few areas contain a high population
density (greater than 4 individuals per acre).
Ranrrewide Trends and Current Threats
Much of the habitat in the range of the species was historically converted to agriculture. In
addition, urban expansion has increased dramatically since 1984. These two land use changes
have contributed to the decline and fragmentation of Stephens’ kangaroo rat populations and
remain the primary threat to the continued existence of the species. Use of rodenticides has the
potential to kill Stephens’ kangaroo rats and reduce populations.
Domestic pets have the potential to kill individual Stephens’ kangaroo rats, and reduce
populations. Crooks and Soule (1999) found that habitat fragments surrounded by approximately
100 residences in southern California were used by approximately 35 hunting, outdoor cats, and
that native rodents constituted approximately 25 percent of known domestic cat prey items.
Hawkins (1998) found that cats at artificially high densities, sustained by supplemental feeding,
reduced abundance of native rodent populations in California.
Environmental Baseline
There are no known extant point locations in the MHCP planning area. One point locality from
1990 is in the grasslands adjacent to Guajome Lake and Pilgrim Creek (S. Montgomery pers.
comm., P. Behrends pers. comm.), however, this is on land owned and managed by the County
and not a part of MHCP. In addition, the current status of this population is uncertain. Stephens’
kangaroo rat is not known to occur in the Carlsbad Subarea, presently or historically.
413
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
A recent discovery (October 1997) of Stephens’ kangaroo rat near Ramona (Ogden 1998)
suggests that the species could occur more widely in grasslands of San Diego County than
previously thought, but suitable grasslands lie mostly north and east of the MHCP planning area.
The species could potentially colonize grasslands or agricultural fields in Oceanside, in the
vicinity of occupied habitat on Camp Pendleton and Fallbrook Navel Weapons Anex. There are
no major populations or critical locations currently identified in MHCP.
414 -
Effects of the Action
Direct Eflects
The MHCP requires the following conditions be met for a city to receive coverage for this
species:
1.
2.
3.
4.
5.
6.
As part of the project review process (e.g., CEQA) for individual projects within the
survey area indicated on the MHCP Database Records Map, a qualified biologist
possessing a Section 10(a)l(A) research permit for this species must survey all areas
containing potentially suitable habitat (open coastal sage scrub, agricultural fields, and
grasslands on soils low in clay content) using approved survey protocols (sign surveys for
burrows, scats, tracks, trails, or other sign of kangaroo rat presence, followed by protocol
trapping surveys to verify species identification if sign is detected). Surveys shall occur
prior to any proposed impact regardless of location inside or outside of the FPA. Surveys
shall be conducted when impacts could occur as a result of indirect impacts by placement
of the project in or adjacent to potential habitat within survey areas shown on the MHCP
Database Records Map.
Any Stephens’ kangaroo rat population shall be treated consistent with the Narrow
Endemic Species Policy (Appendix D) until all criteria for full recovery (i.e., delisting) of
the species have been met.
Conserve and manage natural habitats contiguous with occupied habitat areas to allow for
natural population expansions, to the degree feasible.
Conserve and manage sufficient linkages between occupied areas and other potential or
occupied areas within the MHCP planning area, or outside the MHCP planning area (e.g.,
on MCB Camp Pendleton), to allow for dispersal and colonization.
Manage any occupied reserve areas to maintain early successional phases required by
Stephens’ kangaroo rat. Buffer future developments adjacent to occupied habitat to
preclude predation by domestic cats and minimize other edge effects. Prohibit use of
rodenticides in or near occupied areas.
Projects in or adjacent to occupied habitat shall adhere to the following measures to avoid
or reduce impacts:
a. The removal of native vegetation and habitat shall be avoided and minimized to
the maximum extent practicable. Determination of adequate avoidance and
minimization of impacts shall be consistent with Section 3.7 of the MHCP plan.
414
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 415 -
Deviations from these guidelines shall require written concurrence of the USFWS
and CDFG. For temporary impacts, the work site shall be returned to preexisting
contours and revegetated with appropriate native species. All revegetation shall
occur at the ratios specified in Section 4.3 of the MHCP plan. All revegetation
plans shall be prepared and implemented consistent with Appendix C
(Revegetation Guidelines) and shall require written concurrence of the USFWS
and CDFG. If written objections are not provided by the wildlife agencies within
30 days of receipt of written request for concurrence by the local jurisdiction, then
the deviation may proceed as approved by the local agency. The wildlife agencies
shall provide written comments specifying wildlife agency concerns.
Projects shall be carried out consistent with Appendix B (Standard Best
Management Practices).
Construction-related vehicle travel shall be limited to daylight hours to minimize
roadkill.
For temporary impacts involving trenching or other excavation, measures shall be
taken to prevent Stephens’ kangaroo rats from falling into the trench. Excavations
shall not be covered (e.g., with metal plates or boards) to exclude rodents, because
these may actually attract them to burrow beneath and become entrapped.
To minimize injury or mortality of individuals, the USFWS may authorize
qualified biologists to relocate individual Stephens’ kangaroo rats to nearby
suitable habitat. Authorizations will be granted only to jurisdictions with signed
implementing agreements and issued permits and will require coordination with
the wildlife agencies and their written concurrence. Such salvage relocation may
include exclusion fencing and creation of artificial burrows to increase success, if
deemed appropriate by the wildlife agencies.
b.
c.
d.
e.
The MHCP only preserves 32 percent of remaining grasslands and much of this occurs on clay
soils and in isolated areas that are too small to ensure viable populations of this species.
However, this species is not known to occur within the MHCP at this time.
The City’s subarea plan preserves only 38 percent of grasslands in the City. But, because
Stephens’ kangaroo rat is not known to occur in Carlsbad currently, impacts to potential habitat
are unlikely to result in death of individual kangaroo rats.
Indirect Eflects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse effects to Stephens’ kangaroo rat within the action area.
These indirect impacts include night lighting, human disturbance, depredation by domestic pets,
and habitat degradation, as generally explained and applicable in the “General Indirect Effects”
section.
415
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Human disturbances which may have a detrimental effect to Stephens’ kangaroo rats include
unintentignal disturbance and destruction of burrows by people and pets, and off-road vehicle
use.
416 -
Development associated with plan implementation is likely to increase the number of free-
roaming domestic and feral cats in the plan area, increasing the risk that kangaroo rats attempting
to colonize suitable habitats in Carlsbad will be depredated.
Artificial night lighting associated with development has the potential to increase vulnerability of
Stephens’ kangaroo rats to predation, or inhibit natural behavior in response to a perceived
increased predation risk.
Trenches associated with construction have the potential to lethally trap Stephens’ kangaroo rats.
Road-building associated with the plan will increase the potential for traffic-related mortality of
rats.
Conclusion
We anticipate the proposed action will not directly impact this species and will have few indirect
effects, as described in the analyses above. The avoidance, minimization, and/or mitigation
measures included in the MHCP Subregional Plan will reduce any impacts that may occur to this
species. This Preserve will be adaptively managed, per the measures included in the City’s
Subarea Plan and MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline
for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the action, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because this species is not
expected to occur in the City and it does not preclude the ability for the conditions of coverage to
be met by other Cities.
416
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Pacific Pocket Mouse (Perognathus Zungimembris pacificus)
- 417
Listing Status
The Pacific pocket mouse was federally listed as an endangered species under the emergency
provision of the Act on February 3, 1994 (59 FR 2463), due to its imminent danger of extinction.
This action became final in September of that year. A detailed account of the status, distribution,
taxonomy, ecology, and reproductive characteristics of the Pacific pocket mouse is presented in
the final rule which is hereby incorporated by reference. No critical habitat was designated. A
recovery plan was adopted by the Service on September 28, 1998 (U.S. Fish and Wildlife Service
1998~).
DescriDtion and Identification
All members of the family Heteromyidae are nocturnal granivorous small rodents with external,
fur-lined cheek pouches. The body pelage of the pocket mouse (Perognathus Zongimembris) is
silky. The Pacific pocket mouse shows wide geographic variation in pelage color (Hall 1981).
The dorsal pelage is predominately brown, pinkish buff or ochraceous buff and the ventral pelage
is whitish. Typically, there are two small patches of lighter hairs at the base of the ear. The tail
can be either distinctly or indistinctly bicolored. The Pacific pocket mouse is the smallest of 19
subspecies of the pocket mouse, ranging up to 131 millimeters (5.2 inches) in length from nose to
tip of tail (Hall 1981), and weighing from 7 to 9 grams (0.25 to 0.33 ounces).
Habitat Affinities
This pocket mouse is known to inhabit fine-grained, sandy substrates, coastal strands, coastal
dunes, river alluvium, and coastal sage scrub habitat on marine terraces near the Pacific Ocean
(von Bloeker 1931, Grinnell 1933, Meserve 1972, Erickson 1993). The results of trapping
performed at Camp Pendleton in 1995 suggested that the core of the Pacific pocket mouse
population was confined to sandy soils with low vegetative cover; however, one site consisted of
an ecotone of sparse white sage-dominated scrub between coastal sage scrub and non-native
grassland. Although individual Pacific pocket mice have been observed or collected in several
plant communities, the subspecies has narrow habitat requirements and typically occurs in areas
of sandy soils.
Life Historv
The attributes of the Pacific pocket mouse (P. Zongimembris) and available data that pertain to
the Pacific pocket mouse suggest that the species is facultatively or partially fossorial, relatively
sedentary, primarily granivorous, and able to become torpid, estivate, or hibernate in response to
adverse environmental conditions (Bailey 1939; Kenagy 1973). Pacific pocket mice are among
the smallest mammals known to hibernate, typically from September to April (O'Farrell 1974) or
417
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
November to February (Meserve 1972). In contrast to other hibernators that accumulate fat
reserves fpr hibernation, Pacific pocket mice feed on seed caches stored in their burrows.
Individuals become torpid when deprived of food for 24 to 36 hours. During hibernation, the
body temperature of pocket mice is slightly above that of (and varies directly with) ambient
temperature (Bartholomew and Cade 1957). Periods of dormancy, both hibernation and
estivation, have neither a daily nor strictly seasonal pattern. In captivity, dormant individuals
may show some activity each day within their burrows. Emergence from hibernation (typically
in March) correlates with availability of forb and grass seeds (Meserve 1976).
418 -
Pacific pocket mice feed on the seed and stems of grasses and some forbs (Meserve 1976);
arthropods and their larvae are sometimes eaten (von Bloeker 1931; Meserve 1972, 1976).
Bailey (1939) recorded seeds of the following species from cheek pouches of collected
specimens: “Lotus prostratus, two species of salt bush, heliotrope, mustard, MonanthochEoe,
Franseria, a rush ...” Also from the pouches of collected specimens, von Bloeker (1931)
recorded the seeds of Heterotheca grandiflora, Chrysothamnus, Centauraea melitensis, Croton
californicus, Pluchea sericia, and Hordeum murinum. The Pacific pocket mouse was observed
to drink water regularly in captivity (Bailey 1939).
Relatively little is known of the breeding biology of the Pacific pocket mouse. Meserve (1972)
noted that pregnant and lactating females have been found from April through June with
juveniles noted from June through September. Brylski (1993) observed lactating females in July
of 1993 on the Dana Point Headlands and noted that two litters were produced. Limited
reproduction was attributed to juveniles in the Dana Point Headlands population (Brylski 1993).
After the reproductive season, age structure of populations is dominated by juveniles (U. S. Fish
and Wildlife Service 1998). Two captive individuals lived four and six years in captivity (Bailey
1939). Pocket mouse populations can fluctuate greatly from year to year in both distribution and
abundance, and recolonization of unoccupied but contiguous habitat areas may occur.
Numbers of individual Pacific pocket mice captured per acre range from 10.3 (Brylski 1993) to
0.6 and 2.3 (Ogden 1997). Other subspecies of pocket mouse are often the most abundant rodent
in arid habitats, with densities estimated at up to 400 individuals per acre (Hall 1946). Recapture
locations suggest that Pacific pocket mice are apparently relatively sedentary. Ogden (1997)
reported a movement of 22 meters, while Spencer (1997) reported that most recaptures are at the
initial capture location.
Distribution
The Pacific pocket mouse is historically reported to occur within 4 kilometers (2.5 miles) of the
immediate coast at eight locations from Marina Del Rey and El Segundo in Los Angeles County
south to the vicinity of the Mexican border in $an Diego County. Erickson (1993) reported that
the Pacific pocket mouse was historically recorded at two general locales on Camp Pendleton,
the San Onofre area and the Santa Margarita River Estuary. Known extant populations of this
418
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 419
species are found on the Dana Point Headlands in Dana Point (Orange County) (Brylski 1993)
and on C+mp Pendleton (San Diego County).
-
PoDulation Trend
Historically, the Pacific pocket mouse has been confirmed at two localities in Orange County:
San Joaquin Hills and Dana Point. However, the only known extant population in Orange
County occurs on the Dana Point Headlands, an historic locality that was discovered in the
1930s. The Pacific pocket mouse was known historically from three localities in San Diego
County: San Onofre, Santa Margarita River Estuary, and the lower Tijuana River Valley. Two
populations of Pacific pocket mice were discovered in the vicinity of two known historic sites on
Marine Corps Base, Camp Pendleton, in 1995 (Michael Brandman Associates et al. 1995; Fish
and Wildlife Service 1996). The two separate, small groups of pocket mice detected
approximately one mile from the coast immediately north and south of the San Mateo Creek
drainage are considered to belong to the same population (Fish and Wildlife Service 1997). One
of these populations was estimated at 33 individuals. The third location along the Santa
Margarita River either represents a distinct population or is perhaps part of a larger
metapopulation. The Service captured 54 pocket mice at this site (Fish and Wildlife Service
1996). Numerous recent surveys within the historic range of the species have failed to detect
additional extant populations.
Threats
The leading cause of decline of the Pacific pocket mouse is the large-scale destruction and
fragmentation of habitat due to the conversion of native habitats to urban, suburban, and
agricultural development. Losses resulting from off-road vehicle activities and highways are also
extensive. Artificial night lighting may cause problems for the Pacific pocket mouse through
potential modification of predation rates andor causing direct habitat avoidance. The invasion of
Argentine ants may directly affect Pacific pocket mouse individuals through nestling mortality as
well as indirectly by disrupting key ecosystem functions such as those typically carried out by
native ants. Non-native species, including the red fox (Vulpes vulpes), and feral or domestic cats
are also threats to the population of Pacific pocket mice through increased predation. Domestic
cats are known to prey on Pacific pocket mice (US. Fish and Wildlife Service 1998~).
'.
Environmental Baseline
The pacific pocket mouse is not known to occur in the MHCP planning area. Despite extensive
survey efforts throughout the range, the species likely only occurs in four areas outside of the
MHCP planning area. Habitats in north Oceanside have not been fully surveyed for this species
and have a small possibility of supporting the species. One observation at Lux Canyon,
Encinitas, was not adequately documented to confirm this species, and this location may
subsequently have been developed.
419
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 420
The species is not currently known to occur in Carlsbad. It is not conclusively known to have
occurred in the City. The U. S. Fish and Wildlife Service (1998) does not indicate any record of
museum ipecimens from within what is now Carlsbad. However, Bailey (1939) indicated that the
species was “...abundant on sandy bottoms near the coast of San Diego County.” A habitat
suitability index model prepared by Spencer et al. (2001), taking into account vegetative cover,
soil type, and proximity to the coast, indicates that the City contains 2209 acres of very high to
high-suitability habitat, 380 acres of moderate suitability habitat, and 123 1 acres of low-
suitability habitat.
-
Effects of the Action
Direct Eflects
The MHCP requires the following conditions be met for a city to receive coverage for this
species:
1.
2.
3.
4.
5.
As part of the project review process (e.g., CEQA) for individual projects within the
MHCP area, a qualified biologist possessing a Section 10(a)l(A) research permit for this
species must survey all areas containing potentially suitable habitat (open scrub or
grassland habitat on sandy loam or loamy sand soils, within 6 kilometers [3.7 miles] of
the Pacific coast) using approved survey protocols (trapping surveys conducted for a
minimum of 5 consecutive nights during the seasonal survey windows, as determined by
concurrent USFWS monitoring results at known population sites). Surveys shall occur
prior to any proposed impact regardless of location inside or outside of the FFA. Surveys
shall be conducted when impacts could occur as a result of indirect impacts by placement
of the project in or adjacent to potential habitat.
Until all criteria for downlisting the Pacific pocket mouse from endangered to threatened
status are met (USFWS Recovery Plan), any Pacific pocket mouse population shall be
treated consistent with the Critical Population Policy (Appendix D) and all impacts to the
population avoided. These recovery criteria include protection and management of 10
viable populations distributed throughout the species’ historic geographic range.
Allow for the reintroduction of Pacific pocket mouse in preserve areas supporting suitable
habitat, as defined by ongoing research for the Pacific pocket mouse.
Manage any populations to remove threats, including exotic predators and human
disturbance. Buffer future developments adjacent to occupied habitat to reduce predation
by domestic cats and minimize other edge effects (e.g., artificial lighting, trampling,
Argentine ant invasion). Manage vegetation structure, if necessary using controlled
burning or hand thinning of shrub cover, to optimize habitat quality for Pacific pocket
mouse, or with adaptive management practices developed by ongoing research and
monitoring.
Conserve and manage natural habitats contiguous with occupied habitat areas to allow for
natural population expansions.
420
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
6.
42 1 -
Projects in or adjacent to occupied habitat shall adhere to the following measures to avoid
or reduce impacts:
a. The removal of native vegetation and habitat shall be avoided and minimized to
the maximum extent practicable. Determination of adequate avoidance and
minimization of impacts shall be consistent with Section 3.7 of the MHCP plan.
Deviations from these guidelines shall require written concurrence of the USFWS
and CDFG. For temporary impacts, the work site shall be returned to preexisting
contours, with the same soil composition and depth, and revegetated with
appropriate native species. All revegetation shall occur at the ratios specified in
Section 4.3 of the MHCP plan. All revegetation plans shall be prepared and
implemented consistent with Appendix C (Revegetation Guidelines) and shall
require written concurrence of the USFWS and CDFG. If written objections are
not provided by the wildlife agencies within 30 days of receipt of written request
for concurrence by the local jurisdiction, then the deviation may proceed as
approved by the local agency. The wildlife agencies shall provide written
comments specifying wildlife agency concerns.
Projects shall be carried out consistent with Appendix B (Standard Best
Management Practices).
Construction-related vehicle travel shall be limited to daylight hours to minimize
roadkill.
For temporary impacts involving trenching or other excavation, measures shall be
taken to prevent any Pacific pocket mouse from falling into the trench.
Excavations shall not be covered (e.g., with metal plates or boards) to exclude
mice, because these may actually attract mice to burrow beneath and become
entrapped.
Projects in or adjacent to occupied Pacific pocket mouse habitat shall be
constructed to avoid the active season to the maximum extent practicable. The
active season shall be defined as March 15 through October 15, unless monitoring
suggests that the Pacific pocket mouse are active outside that period during the
year of interest.
b.
C.
d.
e.
Since the pacific pocket mouse is likely extirpated from the planning area, no direct effects to the
species are expected from the MHCP Subregional Plan. Using the habitat suitability index
model developed for this species by Spencer et a1 (2001), the MHCP indicates that 54 percent of
very high to highly suitable habitat within MHCP would be conserved and 87 percent of
moderate suitability habitat would be conserved due to the plan. Within the City of Carlsbad, 52
percent of very high to highly suitable habitat and 85 percent of moderate suitability habitat
would be conserved in the City.
Indirect Effects
42 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse affects to undiscovered Pacific pocket mouse populations
and individuals within the HMP area. These indirect impacts include night lighting, human
disturbance, depredation by domestic pets, and habitat degradation, as generally explained and
applicable in the “General Indirect Effects” section.
422 -
Human disturbances which may have a detrimental effect to Pacific pocket mice include
unintentional disturbance and destruction of burrows by people and pets, and off-road vehicle
use.
Domestic pets have the potential to kill individual Pacific pocket mice, and reduce populations.
House cats (Felis catus) are known to prey on Pacific pocket mice in the Dana Point population
(U. S. Fish and Wildlife Service 1998). Crooks and Soule (1999) found that habitat fragments
surrounded by approximately 100 residences in southern California were used by approximately
35 hunting, outdoor cats, and that native rodents constituted approximately 25 percent of known
domestic cat prey items. Hawkins (1998) found that cats at artificially high densities, sustained
by supplemental feeding, reduced abundance of native rodent populations in California.
Artificial night lighting associated with development has the potential to increase vulnerability of
Pacific pocket mice to predation, or inhibit natural behavior in response to a perceived increased
predation risk.
Use of rodenticides has the potential to kill Pacific pocket mice and reduce populations.
Conclusion
We anticipate the proposed action will not directly impact this species and will have few indirect
effects, as described in the analyses above. The avoidance, minimization, and/or mitigation
measures included in the MHCP Subregional Plan will reduce any impacts that may occur to this
species. This Preserve will be adaptively managed, per the measures included in the City’s
Subarea Plan and MHCP Subregional Plan, which will further reduce the indirect effects and
benefit the species. After reviewing the current status of this species, the environmental baseline
for the action area, the effects of the proposed action, and the cumulative effects, it is the
Service’s biological opinion that the action, as proposed, is not likely to jeopardize the continued
existence and recovery of this species. In addition, the City’s lack of coverage for this species is
not likely to jeopardize the continued existence of this species because this species is not
expected to occur in the City and it does not preclude the ability for the conditions of coverage to
be met by other Cities.
422
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Northwestern San Diego Pocket Mouse (Chaetodipusfallaxfall~)
- 423
Listing Stitus
The northwestern San Diego pocket mouse is not federally listed. The California Department of
Fish and Game considers it a California Species of Concern.
DescriDtion and Identification
All members of the family Heteromyidae are small nocturnal granivorous rodents with external,
fur-lined cheek pouches. The body pelage of the San Diego pocket mouse is harsh, with spines
on the rump. The dorsal pelage is predominately rich brown, becoming blackish over the rump.
The ventral pelage is white or whitish, and divided from the brown dorsal pelage by a buff lateral
line. The tail is crested with longer hairs on the dorsal surface. The San Diego pocket mouse
ranges between 176-200 millimeters (6.9-7.9 inches) in length from nose to tip of tail (Hall
1981). The northwestern San Diego pocket mouse is one of six subspecies of San Diego pocket
mouse (Williams et al. 1993). The diploid chromosome number of the San Diego pocket mouse
shows a moderate level of genetic heterozygosity (4-7 percent), and is similar to other non-
heteromyid rodents, which typically are heterozygous at between 4 and 5 percent of their
allozyme loci (Patton and Rogers 1993). It is unclear, however, whether this observed
heterozygosity relects true genetic variation or is an artifact of the choice of proteins that were
selected for analysis (Patton and Rogers 1993).
Habitat Affinities
Primary habitat of the Northwestern San Diego pocket mouse includes arid habitats with a scrub
component (such as coastal sage scrub, chaparral, oak woodlands, and annual grasslands) and
sandy herbaceous areas in association with rocks or coarse gravel (Grinnell 1933; Miller and
Stebbins 1964). Bleich (1973) recorded the highest populations of the San Diego pocket mouse
in coastal sage scrub supporting a mixture of coastal sagebrush (Artemisia califomica) and
California buckwheat (Eriogonum fasciculatum) on the Naval Weapons Station, Fallbrook
Annex in northwestern San Diego County, but it was also relatively abundant in chaparral. The
San Diego pocket mouse generally exhibits a strong microhabitat affinity for moderately gravelly
and rocky substrates (Bleich 1973; Price and Waser 1984).
.
Life *stow
Like other desert-adapted heteromyid rodents, the San Diego pocket mouse is primarily a
granivore (seed eater). In a study of a rodent community in Imine, Orange County, Meserve
(1976) determined that the diet of the San Diego pocket mouse consisted almost entirely of seeds
during the autumn and early winter. The pocket mouse harvested seeds of the shrubs Eriogonum,
Rhus, and Artemisia in the winter and spring, and then returned to grass seeds in the summer.
423
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 424
Herbaceous forbs and green grasses were seldom utilized except in the latter part of the spring.
Insects wFre also taken.
-
Beyond specialization on seeds, little is known of the foraging behavior of the San Diego pocket
mouse. Howerver, Reichman and Price (1993) provide a comprehensive treatment of heteromyid
foraging that probably can be generalized to the San Diego pocket mouse. Pocket mice possess
external, fur-lined cheek pouches that promote collecting and caching of seeds either in scatter-
or larderhoards, but it is not known which pattern the San Diego pocket mouse exhibits. Pocket
mice (Chaetodipus, Perognathus) tend to forage under shrub and tree canopies, or around rock
crevices, in contrast to kangaroo rats (Dipodomys spp.) and kangaroo mice (Microdipodops spp.)
which tend to forage in more open areas (Reichman and Price 1993). The reliable occurrence of
different species in different microhabitats is well documented, but reasons for these
microhabitat preferences are not well understood. (Reichman and Price 1993). Factors such as
interspecific competition, foraging economics., and predation risk probably are important factors
in microhabitat selection. An interesting laboratory study of microhabitat selection conducted by
Price and Longland (1989) demonstrated that San Diego pocket mice tend to select artificial
patches with aggregated seeds in light (vermiculite) soils. They suggest that San Diego pocket
mice encounter similar habitats in the wild.
Little is known of the specific daily activities of the San Diego pocket mouse, but heteromyids
are primarily nocturnal, with peaks of activity shortly after dusk and again before dawn
(Reichman and Price 1993). The time and temporal pattern of surface activity probably relates to
the availability of food resources, predation risk, energy costs, and other important activities
(e.g., breeding), but nothing is known of these dynamics in the San Diego pocket mouse. During
the day, pocket mice remain in their day burrows. As described above, pocket mice tend to select
microhabitats with shrub or tree canopy cover or rocky areas for nocturnal foraging. The
association of the San Diego pocket mouse with sage scrub and chaparral and rocky and gravelly
substrates is consistent with this generalization.
McClenaghan (1983) suggests that the San Diego pocket mouse may become torpid during
periods of cold weather, but a review of the physiological ecology literature for heteromyids by
French (1993) indicates that the San Diego pocket mouse probably only engages in short bouts of
torpor during times of energetic emergency and can only tolerate body temperatures down to 10-
15 degrees Celsius. Because this species inhabits a relatively mild, coastal environment, it
probably forages on the surface year-round. It has been trapped on the surface in all months
(Bleich 1973). See discussion of physiological ecology below.
There is little information regarding the reproduction of the San Diego pocket mouse, and the
few studies that have been conducted were of relatively short duration, McClenaghan (1983) and
Bleich (1973) both noted seasonal reproduction in the San Diego pocket mouse, with peak
activity in the spirng and ealy summer. McClenaghan conducted a two-year study of the San
Diego pocket mouse in Jacumba in extreme southeastern San Diego County (possibly C.5
424
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 425
paEEidus) and found that 55-100 percent of captured mice were in reproductive condition in the
spring. Reproductive condition was temporally correlated with peak herbaceous plant
production. McClenaghan also noted an earlier onset of breeding in the milder of the two
winters, but the duration of the study was too short to draw valid conclusions about this
relationship.
-
Like other heteromyids, the San Diego pocket mouse likely has a relatively low reproductive
output. According to data summarized by Jones (1993), the typical litter size of a San Diego
pocket mouse is four pups, and the gestation period is about 25 days. Nothing is known of the
number of litters produced per year, the timing of weaning or reproductive potential of young-of-
the-year. However, most heteromyids show flexible reproductive strategies, with the capacity to
produce at least two litters in good years and with females capable of breeding in their natal
season while, on the other hand, foregoing reproduction altogether in poor years (Jones 1993). It
is expected that the San Diego pocket mouse employs similar reproductive flexibility.
The only information regarding survival of the San Diego pocket mouse in the wild is from
McClenaghan (1983). In a two-year study in Jacumba, McClenaghan recorded an average
survival on his study site of 5.2 months, with 18 months as the longest observed survival. The
average monthly survival rate was 0.77 and no sex difference was observed. It should be noted,
however, that these data do not separate disappearances from the study site due to mortality from
disappearances due to emigration. The San Diego pocket mouse is known to survive in captivity
up to 8 years (Jones 1982 as cited in Nowak 1991). This observed longevity is consistent with
other heteromyids (Jones 1993).
In a review of Jones’ (1993) discussion of dispersal patterns of heteromyids, no data were found
concerning dispersal of the San Diego pocket mouse and there were very limited data for other
pocket mouse species. Based on the data available, a conservative assumption is that pocket
mice do not disperse great distances. Jones (1993) cites work demonstrating that while in one
study 25-30 percent of Chaetodipus fomzosus made dispersal movements greater than 500 feet,
in another study of the same species only 5 percent of the individuals shifted home ranges, and in
a third study recapture rates were 62 percent for males and 55 percent for females (high recapture
rates indicate relatively sedentary behavior).
Very little is known of the socio-spatial behavior of the San Diego pocket mouse. MacMillen
(1964; as cited by Jones 1993) reported little intrasexual home range overlap, but there was
evidence of intersexual home range overlap. Average home ranges were reported by MacMillen
to be 0.36 hectare (0.9 acre) for males and 0.25 hectare (0.6 acre) for females.
Pocket mice and other heteromyids modify their environments (Brown and Harney 1993; Price
and Jenluns 1986). They dig burrows, which moves the soils and provides habitat and refugia for
other species, including other rodents, reptiles, amphibians, birds and invertebrates. Collection,
storage and consumption of seeds by kangaroo rats, for example, have profound effects on the
425
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
vegetation structure of the habitats they occupy (Price and Jenkins 1986). In addition, resource
use by poFket mice and kangaroo rats substantially overlaps with that of seed-eating birds and
harvester ants. However, in a literature review of effect of granivorous rodents on the plant
community, Price and Jenkins (1986) cautioned against drawing broad generalizations because
specific effects will be influenced by competitor densities, climate and soil conditions, rodent
densities, seed preferences, and caching behavior.
426 -
Typical of desert-adapted heteromyids, San Diego pocket mice apparently do not need to drink
water (French 1993); they can utilize metabolic water.
Distribution
C. J: fullax occupies the basins and slopes on the Pacific side of the mountains of southern
California and northern Baja California, Mexico. It is a fairly common species where suitable
habitat remains (P. Behrends, S. Montgomery, M Pavelka, and W. Spencer pers. comm.[in
SANDAG 20031). Marginal records of the northwestern San Diego pocket mouse include
Claremont; San Bernardino; Banning; and Jacumba (Hall 1981), and San Jacinto Lake, Riverside
County (Mearns 1901). The northwestern San Diego pocket mouse occurs throughout western
Riverside County and has been collected at elevations from 138 meters (452 ft) as Palm Springs,
Riverside County, to 1,835 meters (6,018 ft) on the northern slopes of the San Bernardino
Mountains in San Bernardino County (Lackey 1996). It is uncertain where the boundary between
the northwestern San Diego pocket mouse and the pallid San Diego pocket mouse (C$ pullidus)
lies. The pallid San Diego pocket mouse occurs on the eastern slopes of the Peninsular Ranges
in eastern Riverside County, but occurs in the transitional Cabazon area of Riverside County and
the San Felipe Valley in San Diego County (Hall 1981). A transition zone between the two
subspecies may occur in the eastern portion of the Anza or Tenvilliger valleys or more to the east
in the Santa Rosa Mountains.
Population Trend
Little is known of the population trend of the San Diego pocket mouse. However, the amount of
habitat available to San Diego pocket mice has decreased drastically since European settlement
of southern California, and the rate of habitat loss has accelerated in the last 20 years. For
example, it is estimated that up to 90 percent of coastal sage scrub vegetation has been lost as a
result of development and land conversion (Westman 1981a, 1981b, Barbour and Major 1977),
and coastal sage scrub is considered to be one of the most depleted habitat-types in the United
States (Kirkpatrick and Hutchinson 1977, O’Leary 1990). Within the MHCP area, other habitat
types used by the San Diego pocket mouse (i.e., chaparral, grassland ...) have undergone similar
declines. It is reasonable to assume that there has been a concomitant reduction in populations of
San Diego pocket mouse.
Threats
426
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 427
The San Diego pocket mouse appears to be sensitive to habitat fragmentation and degradation.
Bolger etpl. (1997) studied rodent diversity and abundance in isolated habitat fragments of
varying size and age in San Diego County. The San Diego pocket mouse tended to occur in
habitat patches with 90-100 percent shrub cover, with only two of eight occupied patches having
shrub cover of 50 percent and 75 percent. Bolger et ul. tentatively concluded that canyon
fragments under 25 hectares (62 acres) and isolated for more than 30 years support few
populations of native rodents, including the San Diego pocket mouse. Their data also suggest
that isolated habitat patches must be at least 25 hectares (62 acres) to 80 hectares (198 acres) to
sustain native rodent populations.
-
The leading cause decline of the Pacific pocket mouse is the large-scale destruction and
fragmentation of habitat due to the conversion of native habitats to urban, suburban, and
agricultural development. Losses resulting from off-road vehicle activities and highways are also
extensive. Artificial night lighting may cause problems for the Pacific pocket mouse through
potential modification of predation rates andor causing direct habitat avoidance. The invasion of
Argentine ants may directly affect Pacific pocket mouse individuals through nestling mortality as
well as indirectly by disrupting key ecosystem functions such as those typically canied out by
native ants. Non-native species, including the red fox (Vulpes vulpes), and feral or domestic cats
are also threats to the population of Pacific pocket mice through increased predation.
Environmental Baseline
There are only two location points in the MHCP planning area, but this primarily reflects lack of
survey effort for the species, which is expected to be fairly abundant in appropriate habitats
(SANDAG 2003). There are no major populations or critical locations in the planning area.
The MHCP area includes 22,842 acres of appropriate vegetation for Northwestern San Diego
pocket mouse without clay soils. The HMP area includes approximately 3,901 acres of scrub,
oak woodland, and grassland habitat types without clay soils.
Effects of the Action
Direct Effects
Though no species-specific conservation measures are proposed for the Northwestern San Diego
pocket mouse, it is likely to benefit from the preserve management and monitoring program.
This program will address ecologically deleterious influences on the preserve, including. but not
limited to public access, hydrology and flood control, erosion, fire, and exotic plants and animals.
The MHCP would allow impacts to northwestern San Diego pocket mouse habitat. Conversely,
the MHCP conserves 13,934 acres of scrub, oak woodland, or grassland habitat without clay
soils.
427
Carlsbad Subarea Plan Biological and Conference Opinions (IFWS-SDG-847.4)
The City would conserve 2,341 acres of scrub, oak woodland, or grassland habitat without clay
soils. ,
428 -
Indirect Eflects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause significant adverse affects to Northwestern San Diego pocket mouse within the
action area. These indirect impacts include night lighting, human disturbance, depredation by
domestic pets, and habitat degradation, as generally explained and applicable in the “General
Indirect Effects” section.
Human disturbances which may have a detrimental effect to Northwestern San Diego pocket
mice include unintentional disturbance and destruction of burrows by people and pets, and
off-road vehicle use.
Domestic pets have the potential to kill individual Northwestern San Diego pocket mice, and
reduce populations. Crooks and Soule (1999) found that habitat fragments surrounded by
approximately 100 residences in southern California were used by approximately 35 hunting,
outdoor cats, and that native rodents constituted approximately 25 percent of known domestic cat
prey items. Hawkins (1998) found that cats at artificially high densities, sustained by
supplemental feeding, reduced abundance of native rodent populations in California.
Artificial night lighting associated with development has the potential to increase vulnerability of
Northwestern San Diego pocket mice to predation, or inhibit natural behavior in response to a
perceived increased predation risk.
Use of rodenticides has the potential to kill Northwestern San Diego pocket mice and reduce
populations.
Conclusion
We anticipate the proposed action will directly and indirectly impact this species, as described in
the analyses above. The avoidance, minimization, and/or mitigation measures included in the
MHCP Subregional Plan will reduce any impacts that may occur to this species. This Preserve
will be adaptively managed, per the measures included in the City’s Subarea Plan and MHCP
Subregional Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the action, as proposed, is not likely to jeopardize the continued existence and recovery of
this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize the
continued existence of this species because the City will be conserving 60 percent of this species
428
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 429
predominant habitat and no major populations or critical locations for this species exist in the
City. ,
-
429
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Lepus califomicus bennettii (San Diego black-tailed jackrabbit)
Status of the SDecies
- 430
Listing Status
The San Diego black-tailed jackrabbit is not a federally listed species. However, the State of
California Department of Fish and Game places this species on the Special Concern list.
Species Description
Lqus califomicus bennettii is a member of the Leporidae (hare) family. L. c. bennettii is a
distinctive, long legged hare with very long ears. The tail is black (or partly black) dorsally and
grayish ventrally and nearly white beneath (Jameson 1988 and Ingles 1965). The black portion
of the tail is usually only on the upper side and can continue to run up onto the rump.
Distribution
The black-tailed jackrabbit is widely distributed in the state, except at the highest elevations,
above - 2500 meters (Jameson 1988). They are abundant at lower elevations in herbaceous and
desert-shrub areas, and open early stages of forest and chaparral habitats (CDFG 2003). The
black-tailed jackrabbit is common throughout western San Diego County including the Subarea,
however the range of the subspecies is not clearly understood.
Habitat Afinity
This species is common in coastal sage scrub, grassland, and open chaparral habitats. This
species inhabits open plains, fields, and deserts, especially open country with scattered thickets or
patches of shrubs (Caire et al. 1989, as cited in Natureserve 2003). Black-tailed jackrabbits
prefer to have some open area for foraging and dense cover for nesting and predator avoidance.
Life History
The San Diego black-tailed jackrabbit feeds primarily on herbs and grasses, including cultivated
crops. Like most hare species the San Diego black-tailed jackrabbit is sensitive to the quality and
amount of food available. They are very adaptable and will eat grasses, forbs, or any other
available vegetation (CDFG 2003). Although they do not require water, they will drink if it is
present. As a result of the nature of the food, reproduction may occur at any time of the year
(Jameson and Peeters 1988) although the greatest number of births occur between April and May
(Ingles 1965, as cited in CDFG 2003). Three to seven young are born in a litter which are birthed
in a vegetation-covered depression in the ground; however, no special nest structure is built
(CDFG 2003). The young are born with their eyes open and weaned at - 3 weeks (CDFG 2003). -
430
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
The long ears of the jackrabbit not only aid in the detection of predators, but also in the release of
excess he?. They may travel up to a mile from their daytime cover, a shallow depression under
any available shrub, to their nighttime feeding area (Natureserve 2003).
43 I -
Population Trend
Population data is insufficient to justify any type(s) of trends, although the species remain
relatively common in larger areas of appropriate habitat. Larger areas are defined as supporting
home ranges of 45 acres (Lechleitner 1958, as cited in CDFG) and a density of 100 black-tailed
jackrabbits per square kilometer (Flinders and Hansen 1973, as cited in CDFG).
Threats
Black-tailed jackrabbits are threatened by habitat loss and fragmentation. Habitat loss will effect
black-tailed jackrabbits because they are known to require 1 to 3 square kilometers (247 to 741
acres) in Utah (Natureserve 2003), and average 0.19 square kilometers (46 acres) in California
(California Department of Fish and Game 2003).
Environmental Baseline
There are no major populations or critical locations in the MHCP planning area, however, there
are scattered observations throughout natural habitats in Encinitas, Escondido, Oceanside, and
Carlsbad.
Within the Subarea, there are no known major populations or critical locations of black-tailed
jackrabbits. However, San Diego black-tailed jackrabbits are widespread throughout both
developed and undeveloped portions of western San Diego County. They are known to occur in
at least 8 locations within natural habitats of Carlsbad, from the coast to inland and from
Encinitas to Oceanside. Currently, there are 3,289 acres of habitat in the City, comprised of
coastal sage scrub, chaparral, and grassland, that may support an unknown population of black-
tailed jackrabbits.
b
Effects of the Action
Direct Eflects
The MHCP does not provide specific conservation measures for this species because general
habitat management actions instituted for other species are expected to benefit this subspecies as
well.
Black-tailed jackrabbits will be partially conserved due to the preservation .and management of
some large blocks of habitat that are connected to even larger blocks of habitat outside the
43 1
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
planning area. The MHCP will conserve approximately 51 percent of suitable habitat and 71
percent of the limited species points on record. However, the grassland ecological community is
not adequately preserved and does not substantially contribute to the conservation this
subspecies. The City will conserve 55 percent of suitable habitat and 69 percent of known
species points on record.
432 -
Zndirect effects
Indirect impacts are anticipated with the implementation of the Subarea plan, and have the
potential to cause adverse effects to black-tailed jackrabbits in the Subarea. These indirect
impacts include night lighting, human disturbance, and habitat loss/degradation/fragmentation,
and loss of foraging availability as generally explained and applicable in the “General Indirect
Effects” section.
Other indirect effects include road-kill mortality. The development of land to include associated
roads results in habitat loss and fragmentation, which has an impact on San Diego black-tailed
jackrabbits. The addition of new roads also increases the probability that black-tailed jackrabbits
will cross to find suitable habitat, in turn increasing the chances that black-tailed jackrabbits will
come in contact with a vehicle.
Conclusion
We anticipate the proposed action will directly and indirectly impact this species, as described in
the analyses above. The avoidance, minimization, andor mitigation measures included in the
MHCP Subregional Plan will reduce any impacts that may occur to this species. This Preserve
will be adaptively managed, per the measures included in the City’s Subarea Plan and MHCP
Subregional Plan, which will further reduce the indirect effects and benefit the species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the action, as proposed, is not likely to jeopardize the continued existence and recovery of
this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize the
continued existence of this species because the City will be conserving 55 percent of this species
predominant habitat and no major populations or critical locations for this species exist in the
City.
43 2
Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Felis concolor (Mountain lion)
Status of the SDecies
- 433
Listing status
The mountain lion was designated as a California Department of Fish and Game Specially
Protected mammal in 1998. It may not be taken or possessed without a permit from the
California Department of Fish and Game. This species is not federally listed.
Species Description
Felis concolor is the largest feline in North America with females 36-60 kilograms, and males
67-103 lulograms; their bodies are 1-1.3 meters in length, excluding tail (0.5 - 1.0 meters). The
pelage of mountain lions has a short and coarse texture. The general coloration ranges from a
yellowish brown to grayish brown on the upper parts and a paler, almost buffy, color on the belly.
The throat and chest are whitish. Mountain lions have a pinkish nose with a black border that
extends to the lips. The muzzle stripes, the area behind ears, and the tip of tail are black. The
ears are small and rounded. The eyes of mature animals are grayish brown to golden. The tail is
long, cylindrical, and about one-third of the animal’s total length. The limbs are short and
muscular. The feet are broad, with four digits on hind feet and five on forefeet. The pollex is
small and set above the other digits. The retractile claws are sharp and curved. The skull of the
mountain lion is noticeably broad and short. The forehead region is high and arched. The
rostrum and the nasal bones are broad. Upper parts of the body are grizzled gray or dark brown
to shades of cinnamon or ferruginous, with the color most intense along the mid-dorsal line from
the top of the head to the base of the tail. The shoulders and flanks are lighter, with underparts
dull whitish. Young are spotted with black.
Distribution
The mountain lion has the largest geographical distribution of any mammal species in the
western hemisphere, but it is restricted primarily to unpopulated regions in western North
America (Hall and Kelson 1959). The species had become relatively uncommon in the early 20*
century due to human persecution, but a moratorium on hunting was passed in California in
1972, and the species was given special protection under State Proposition 117 in 1990, which
has led to a dramatic increase in populations. In coastal San Diego County, mountain lions
occupy most larger blocks of habitat, with recent observations at Camp Pendleton, Palomar,
Carlsbad, Oceanside, San Marcos, Escondido, Laguna Indian Reservation, Los Pefiasquitos
Canyon Reserve, Del Mar, Torrey Pines State Park, NAS Miramar, Poway, Sweetwater River,
and Otay Lakes.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Ha bitat Afin ity
- 434
Mountain lions use rocky areas, cliffs, and ledges that provide cover within open woodlands and
chaparral, as well as riparian areas that provide protective habitat connections for movement
between fragmented core habitat. A study of diurnal bedding habitat in northeast Oregon
suggests that lions also need both vertical and horizontal cover components, such as rocks and
downed logs, to feel secure enough to bed (Akenson et al. 1996).
L$e History
The average home range for male mountain lions is 187 square kilometers and 74 square
kilometers for females (Sweanor et al. 1999). Between 1,000 and 2,200 square kilometers
(247,100 and 543,600 acres) of preferred habitat is needed to provide ample home range and
dispersal territory for a viable population based on previous studies by Beier (Beier 1990, 1993).
Models indicate a low extinction rate (<2 percent) when the habitat area meets or exceeds 2,200
square kilometers, and increases the extinction rate as habitat area shrinks below 2,200 square
kilometers, based on studies in the Santa Ana mountains of southern California (Beier 1995).
Migration distances are directly related to prey activity, as mountain lions will follow mule deer
herds, their primary food source (Pierce et al. 1999, as cited in Nature Serve 2003). The longest
dispersal distances are 2 15 square kilometers for males and 79 square kilometers for females
(Sweanor et al. 1999).
Huge expanses of land are needed to support a density of 3 to 4 adult mountain lions per 100
square kilometers of land (Kitchener 1991, as cited in Nature Serve 2003) considering the
subsequent dispersal area needed as 80 percent of males and 25 percent of females disperse from
their natal home ranges (Beier 1993). Additionally, the travel area needed to locate prey, as a
hunting mountain lion travels an average of 5.5 miles per night (Beier 1993), illustrate that any
connection between 2 isolated patches is better than no connection at all (Beier 1995).
Studies of general activity patterns of lions suggest that lions have peaks of activity around
sunset and sunrise (Laundr6 et al. 1996; Van Dyke et al. 1996). Laundrk et al. (1996) found that
lions in south-central Idaho and northwestern Utah moved approximately 10 miles (males) to 12
miles (females) per day and that most of the day was spent in low level activities of walking and
feeding.
The diet of mountain lions includes mule deer as their principal prey, but also other ungulates,
rabbits and larger rodents (Ackerman et al. 1984; Cunningham 1996; Leopold and Krausman
1986; Peirce and Cashman 1996; Spalding and Lesowski 1971). Cunningham (1996) and Peirce
and Cashman (1996) found that cattle are a substantial component of the mountain lion’s diet in
Arizona. In southern California, Arizona, and New Mexico mountain lions also are known to
prey on desert bighorn sheep (Ovis canadensis) (Krausman et al. 1989; Logan et al. 1996a;
Peirce and Cashman 1996; Rubin et al. 1996). Leopold et al. (1986) and Peirce and Cashman
i
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 435 -
(1996) suggest that mountain lions change diets to smaller prey when ungulate populations (deer,
desert bighorn, collared peccary [Tayassu tajacu]) decline.
Mountain lions are polygamous. Courtship and mating occur from December to March.
Gestation periods last from 82 to 96 days. Females usually give birth every other year. Litters
vary in size from 1 to 6 cubs with an average of 3 or 4. Birth weight is between 226 to 453
grams. The cubs open their eyes 10 days after birth. At the same time their ear pinnae unfolds,
their first teeth erupt, and they begin play behavior. The cubs are fully weaned at about 40 days
of age. Mother and cubs remain together for as long as 12 months. Males reach sexual maturity
at about 3 years of age and females at 2 '/2 years. Females appear to begin consorting with males
at about age 21 months and first litters are produced at ages 22-40 months.
A study of dispersal by juvenile mountain lions in the Santa Ana Mountain Range showed that
dispersal is initiated by the mother abandoning her cub of about 18 months at the edge of her
range (Beier 1996). The cub disperses to the part of urban-wildlife interface farthest from its
natal range and uses temporary home ranges near this interface. Beier (1996) also observed
dispersing individuals using corridors along well covered travel routes, an underpass, areas
lacking artificial lighting, and areas with low residential densities (4 dwelling unit/l6 hectares).
A dispersal study by Sweanor et al. (1996) of a population in the San Andres Mountains of
southern New Mexico showed dispersal at an average of 13.5 months for females and 15.7
months for males. Sixty percent of the females did not disperse from their natal range, whereas
all males did. Females dispersed on average 7.7 miles and males dispersed on average 62.8
miles. Over the five-year study period, 21 progeny and 22 immigrants were recruited into the San
Andres Mountains, and 47 progeny successfully dispersed outside of the mountain range.
A study of lion cub survival rates indicates that annual survival rates of unhunted lions in
southern New Mexico is about 70-72 percent, depending on the method for calculating survival
(Logan et al. 1996b). Natural causes of mortality, in order of frequency, include cannibalism,
starvation, disease, accidental fall and coyote predation (Logan et al. 1996b). Mean annual
subadult survival was 87 percent for females and 60 percent for males, and all deaths were from
intraspecific killing. Mean annual adult female survival was 81 percent and male survival was
90 percent.
Population Trend
The mountain lion had one of the most extensive distributions of all American terrestrial
mammals. It ranged from coast to coast in North America, and from southern Argentina to
northern British Columbia. Hunting pressure and other environmental changes have restricted
their range to relatively mountainous, unpopulated areas. Mountain lions require large areas for
hunting their preferred prey (mule deer) and Beier (1993) has shown through modeling that lion
populations require at least 850 sq. miles to remain stable. Human developments have intruded
upon, greatly reduced, and fragmented this required habitat, thus resulting in apparent increased
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
interactions between humans and mountain lions (e.g. Torres, et al. 1996). This interaction has
resulted ir;l adverse impacts on mountain lions, in addition to habitat loss and fragmentation, in
the form of increased mortality of lions from vehicular collisions, and apparent loss of fear of
humans by lions and consequently more frequent aggressive behavior toward humans (especially
by juvenile lions).
436 -
Threats
The primary threats to the mountain lion are habitat fragmentation, loss of large areas of
undeveloped land, road kills, indiscriminate shootings, animal control measures, and loss of
natural prey base. Using a simulation model, Beier (1993) estimated that lions were at a low
extinction risk in areas at least 2,200 square kilometers in size (about 544,000 ac). The risk of
extinction increases in smaller areas in the absence of immigration. For example, Beier (1993)
estimated that the mountain lion population of about 20 adults in the Santa Ana Mountains in an
area of 2,070 square kilometers. was demographically unstable and that a movement corridor
connection to the Palomar Mountain Range to the east will be important for sustaining this
population.
Human presence also may have adverse effects on mountain lion behavior, and in particular
range use and foraging activities. For example, Van Dyke et al. (1986) studied the reactions of
mountain lions to logging and human activity and found that near human presence, lion activity
peaks shifted to periods after sunset compared to areas with no human activity where activity
peaks occurred within two hours of sunset and sunrise. In addition, juvenile lions encountered
humans more frequently than adult lions, suggesting that dispersing juveniles are at relatively
high risk of encounters with humans. Selected home ranges of both adults and juveniles were in
areas with lower road densities, no recent timber sales, and few or no human residences. On the
other hand, Jalkotzy and Ross (1996) found that mountain lions were relatively unaffected by
summertime human activity (vehicular traffic and camping, equestrian and hiking activities) at
Sheep River, Alberta, Canada, although they did suggest that lions may be more sensitive at kill
sites than along travel routes.
Mountain lions are at risk to a variety of diseases, including feline immunodeficiency virus,
feline leukemia virus, feline infectious peritonitis, canine distemper, panleukopenia, and rabies
(Foley 1996). Mortality from diseases is a potential catastrophe for small, isolated mountain
populations.
Environmental Baseline
There are no major populations or critical locations in the planning area for this species, although
it probably occupies some of the larger natural areas, such as Daley Ranch, and scattered
observations have been made in and near the MHCP planning area. Recent observations have
occurred in Carlsbad, Oceanside, Escondido, and San Marcos.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 437 -
The City is located closely enough to the Santa Ana Mountains to the northeast to provide viable
linkages through the southeast portion of Carlsbad, into the Fallbrook and Palomar areas. This is
beneficia{ for existing mountain lions to traverse for increased prey availability, additional
mating opportunities, and increased habitat area (Beier 1993). The same connectivity would also
hold true for populations within the Daley Ranch area (Beier 1995).
Most of the habitat within the City is already too fragmented to be suitable home range for
mountain lions and there are no known populations or critical locations within the Subarea. It is
probable that this species occupies some of the larger habitat areas such as the Calavera
Highlands, (as scat was positively identified recently) or the Daley Ranch in Escondido.
However, they would not be expected to exist in Carlsbad due to their requirements for very
large blocks of habitat, although the City could act as wildlife corridors. However, the goal of
the MHCP was not to increase mountain lions in developed areas, but rather, not preclude their
current movement or use areas.
Effects of the Action
Direct Effects
The MHCP requires the following conditions be met for a city to receive coverage for this
species:
1. Maintain and enhance habitat linkages between conserved habitat areas that are intended
to support mountain lions. New roads or improvements to existing roads must include
adequate under-crossings and appropriate fencing to accommodate safe movements
between habitats on either side. Placement and design of road crossings and associated
improvements (fencing, vegetation restoration) should be done on site-specific wildlife
movement and biological criteria.
Periodically monitor key habitat linkages to assess their use by mountain lions.
Institute a public awareness campaign to educate people on the importance of large
carnivores in natural ecosystems and ways to avoid problem encounters with mountain
lions.
2.
3.
The mountain lion will benefit from the preservation and management of remaining large blocks
of habitat and linkages to large blocks of habitat outside the MHCP. The MHCP will conserve
17,214 acres (63 percent) of potential mountain lion habitat and the City will conserve
approximately 3,147 acres (62 percent) of mountain lion habitat. The exact number of mountain
lions that will be impacted by implementation of the MHCP Subregional Plan is unknown, as
population estimates are nonexistent. However, due to the proposed plan, the current mountain
lion population is expected to persist with no substantial increase or decrease in numbers.
Overall, the plan to maintain and manage migration and dispersal comdors will benefit the
species by providing linkages to larger habitat.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Indirect eflects
- 438
Indirect impacts are anticipated and have the potential to cause indirect impacts to the mountain
lions within the action area. These indirect impacts include night lighting, noise pollution,
human disturbance, depredation on domestic pets, and habitat loss/degradation/fragmentation,
and loss of foraging availability as generally explained and applicable in the “General Indirect
Effects” section.
Other indirect effects include road-kill mortality. The addition of new roads increases the
probability that mountain lions will have to cross them in order to find suitable habitat, in turn
increasing the chances that mountain lions will come in contact with a vehicle, typically resulting
in a mountain lion casualty. Additionally, mountain lions do not appear to avoid roads within
their home ranges in southern California, especially when these roads are located within riparian
areas (Dickson and Beier 2002, as cited in Sandag 2003). Road-kill mortality was the number
one cause of death for mountain lions in the Santa Ana mountains (Beier 1995) and also affects
their prey, the mule deer. Habitat fragmentation can also lead to an allee effect, in which animals
at a low density may have difficulty finding mates, creating an inverse density-dependence in
fecundity when numbers of one sex are very low (Beier 1993). It can additionally lead to a meta-
population structure, in which there exists a network of semi-isolated populations with some
level of regular or intermittent migration and gene flow among them, in which individual
populations may go extinct, but can then be recolonized from other populations (Meffe and Carol
1997, as cited in Sweanor et aE.1999). Although Carlsbad is probably not an vital habitat area for
mountain lions, these are effects that need to be recognized.
Conclusion
The MHCP Subregional Plan will not result in any direct take of this species. However, the plan
can indirectly adversely affect this species, but the avoidance, minimization, andor mitigation
measures included in the MHCP Subregional Plan will reduce the impacts to this species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the MHCP Subregional Plan is not likely to jeopardize the continued existence and recovery
of this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize
the continued existence of this species because no take of the species is expected to occur and
there are no major or critical populations in the City.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Odocoileus hemionusfuliginata (Southern muIe deer)
- 439
Status of the Species
Listing status
The southern mule deer is a California Department of Fish and Game regulated game species.
This species is not federally listed.
Species Description
Odocoileus hemionus get their name from their large, mule-like ears. They can be identified by
their tails and antlers. The thin, brown tail has a black tip and is surrounded by a white rump
patch. The beam of each antler divides into two equal tines, and in older bucks these may divide
again. 0. h. fuliginata is a dark race of mule deer, and can be hstinguished from the 0. h.
peninsulae (peninsula mule deer) and 0. h. califomicus (California mule deer) by a darker pelage
in both summer and winter. In winter 0. h. fuliginata has a well-defined black line down the
middle of the back, and a tail with a black outer surface. They are a medium-size deer, with
bucks averaging about 220 pounds (100 kg), and does about 155 pounds (70 kg). They exhibit a
distinct, stiff-legged, bouncing gait when running.
Distribution
Mule deer are found throughout California and presently are widespread throughout undeveloped
portions of western San Diego County, although they may be declining in the county. Recently
documented occupied areas include the Laguna Mountains, Camp Pendleton, Torrey Pines,
Miramar, Palomar, Escondido, San Marcos, Carlsbad, Los Peiiasquitos Canyon Reserve, La
Jolla, Poway, Sweetwater River, and Otay Lakes (Bond 1977). Deer require relatively large,
undisturbed tracts of chaparral, coastal sage scrub, and mixed grasslandshrub habitats (Padley
1992).
Habitat AfSinity
Mule deer occur in early to intermediate successional stages of most forest, woodland, and brush
habitats. They prefer a mosaic of various-aged vegetation that provides woody cover, meadow
and shrubby openings, and free water. Brushy areas and tree thickets provide important escape
cover. Vegetative cover is critical for thermal regulation in the winter and summer. Mule deer
frequent various aspects of habitat during the year to aid in thermal regulation (e.g., use south-
facing slopes more in cold weather, and north-facing slopes more in hot weather). Fawning
occurs in moderately dense shrub lands and forests, dense herbaceous stands, and high-elevation
riparian and mountain shrub habitats, with available water and abundant forage (Ahlborn 2000).
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) - 440
Life Hist&
The habitat requirements for home ranges of mule deer may be between 0.3 and 2.4 square
kilometers (74 and 593 acres), and are directly correlated with availability of food, cover and
water (Natureserve 2003). Migration distances can be up to and over 100 kilometers, and are
often in response to rainfall patterns in the southwest (Natureserve 2003). Due to the travel
activity needed to locate forage material, water, and adequate hiding cover, the reason for low to
declining population estimates in southern California is clearly based on the amount of home
range used to find these necessities.
Mule deer are generally most active at twilight, but they may be active day or night. Activity
patterns may be influenced by abrupt changes or extremes in temperature, precipitation, and
relative humidity. In the mountains of California, they migrate downslope in the winter and
migrate to higher elevations in the summer. Home ranges usually are less than 1 mile (1.6 km) in
diameter (Ahlborn 2000). Dasmann and Taber (1956) and Miller (1970) reported that the home
range consists of many small areas from which the deer obtains its life requisites.
Adult does may defend small territories in late spring and early summer, when caring for
newborn fawns. Bucks are usually solitary, although several bucks may form feeding herds in
the spring and summer. As rut begins in August, individuals disperse and tend to avoid each
other during mating activities. Mule deer are serially polygynous. A buck tends an estrous doe
until mating is complete or the buck is displaced by another buck. The gestation period is 195-
212 days. Fawns are born from early April to midsummer, varying geographically. Males and
females are mature sexually at 1.5 years (Ahlborn 2000). Mule deer may live more than 10 years
in the wild, and longer in captivity (Taylor 1956, Wallmo 1981, Anderson and Wallmo 1984).
Population Trend
The southern mule deer is not threatened with extinction within its range, but the present
checkerboard of private property distribution in western San Diego County and urbanization
could result in local extirpation without appropriate conservation measures.
Threats
Natural predators of deer (mountain lions, coyotes, bobcats, and black bears) have been reduced
in number in most areas. In California, periodic overpopulation results in die-offs and
destruction of habitat. Deer populations can respond rapidly to habitat management. However,
populations can decline in response to fragmentation, degradation, or destruction of habitat
caused by urban expansion, incompatible use of land resources (e.g., timber, water, rangeland),
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4) 441 -
and disturbance by humans. Roads are a significant source of direct mortality and habitat
fragment?tion (Ahlborn 2000).
Environmental Baseline
It is thought that mule deer are widespread throughout undeveloped portions of western San
Diego County and fairly common in portions of the MHCP planning area where sufficient habitat
is present. However, the species is apparently disappearing from coastal cities due to habitat
fragmentation (eg Dawson-Los Monos Resrve; I. Kay personal communication). There have
been observations in Carlsbad and mule deer would be expected in some of the larger blocks of
habitat, such as Calavera Preserve, the Villages of La Costa and Daley Ranch in Escondido.
There are no known major population or critical locations of mule deer in MHCP
However, the City of Carlsbad is located closely enough to the Santa Ana Mountains to the north
to provide viable linkages through the southeast portion of Carlsbad, into the Fallbrook and
Palomar areas. This is beneficial for existing mule deer to traverse for increased foraging activity,
additional mating opportunities, and increased habitat area (Beier 1993). The same connectivity
would also hold true for populations within the Daley Ranch area.
Effects of the Action
Direct Effects
The MHCP requires the following conditions be met for a city to receive coverage for this
species:
1. Maintain and enhance habitat linkages between conserved habitat areas that are intended
to support mule deer. New roads or improvements to existing roads must include
adequate under-crossings and appropriate fencing to accommodate safe movements
between habitats on either side. Placement and design of road crossings and associated
improvements (fencing, vegetation restoration) should be done on site-specific wildlife
movement and biological criteria.
Periodically monitor key habitat linkages to assess their use by mule deer. 2.
Mule deer will benefit from the preservation and management of remaining large blocks of
habitat and linkages in the MHCP to large blocks of habitat outside the MHCP. Additionally, the
MHCP will conserve 17,214 acres (63 percent) of coastal sage scrub, chaparral, and riparian
woodland communities that will directly benefit mule deer. The exact number of mule deer that
will be impacted by implementation of the Subarea plan is unknown.
The City’s plan to maintain and manage migration and dispersal corridors will benefit the
species. The City will conserve 3,147 acres (62 percent) of suitable habitat types within the City.
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Carlsbad Subarea Plan Biological and Conference Opinions (FWS-SDG-847.4)
Zndirect efects
- 442
Indirect impacts are anticipated and have the potential to cause adverse effects to mule deer in the
Subarea. These indirect impacts include night lighting, human disturbance, and habitat
loss/degradation/fragmentation, and loss of foraging availability as generally explained and
applicable in the “General Indirect Effects” section.
Other indirect effects include road-kill mortality. The development of land to include associated
roads results in habitat loss and fragmentation which adversely affect mule deer. The addition of
new roads also increases the probability that a mule deer will cross to find suitable habitat, in
turn increasing the chances that mule deer will come in contact with a vehicle. Thus,
urbanization could result in local extirpation as roads are a significagt source of direct mortality
(Sandag 2003).
Conclusion
The MHCP Subregional Plan will not result in any direct take of this species. However, the plan
can indirectly adversely affect this species, but the avoidance, minimization, and/or mitigation
measures included in the MHCP Subregional Plan will reduce the impacts to this species. After
reviewing the current status of this species, the environmental baseline for the action area, the
effects of the proposed action, and the cumulative effects, it is the Service’s biological opinion
that the MHCP Subregional Plan is not likely to jeopardize the continued existence and recovery
of this species. In addition, the City’s lack of coverage for this species is not likely to jeopardize
the continued existence of this species because no take of the species is expected to occur and
there are no major or critical populations in the City.
442