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HomeMy WebLinkAboutCT 02-14; Bressi Ranch Residential; Tentative Map (CT) (19)United States Department of the Interior FISH AND WTUDLJFE SERVICE Ecological Services Carlsbad Fish and Wildlife Office 2730 Loker Avenue Wc$t Carlsbad, California 92008 In Reply Refer To: FWS-SDG-915.2 Colonel John Carroll District Engineer. ••$ LlQf^ V Li- U.S. Army Corps of Engineers !> *l~v'~- Los Angcies District *. .-> n — P.O. Box 532711 u;to<su~~- Los Angeles, CA 90053-2325 Attn: Ms. Shannon Bryant Re: Formal Section 7 Consultation on Bressi Ranch development, Carlsbad. San Diego County. California (1-6-00-F-915) (Corps file No.98004300 SKB) Dear Colonel Carroll: This document transmits the Fish and Wildlife Service's (Service) biological opinion based on our review of the proposed Bressi Ranch development located in the City of Carlsbad, San Diego County, California, and its effects on the coastal California gnatcatcher (PolioptUa califomica californica) and its critical habitat in accordance with section 7 of the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et seq.). Your July 26. 2000, request for formal consultation was received on August 2, 2000 We initiated consultation on August 15, 2000. We received the Biological Assessment pertaining to this project under separate cover on September 11.2000. This biological opinion is based on information provided in: your July 26, 2000, request for consultation; the Biological Assessment (BA) dated February 29. 2000; the draft Biological Technical Report dated April 10, 2000; a letter from the applicant's consultant dated November 27, 2000; maps obtained during informal consultation between our staffs; and other information available in our files. A complete administrative record of this consultation is on file at the Service's Carlsbad Fish and Wildlife Office. CONSULTATION HISTORY Service personnel have had several meetings with project proponents concerning this proposed development. On January 22, 1998, the Service, Corps, the applicant, and the applicant's biological consultant met on the site, touting areas of proposed impacts and conserved areas. On July 2, 1998, the Service, Corps, California Department of Fish and Game, the City of Carlsbad, 17 «->7 Hac oooct7.(u«<~yi: *tH AOU±O «ona 3UJt) John Carrol I (FWS-SDG-915) 2 the applicant, and the applicant's biological consultant met. Discussion topics included restoration of Agricultural land to coastal sage scrub, location of high-density housing, and the need for an alternatives analysis for proposed wetland impacts. On August 13, 1998, the Service. Corps, applicant, and the applicant's biological consultant met to discuss project alternatives and project design. The Corps inquired as to why avoidance of wetland impacts was not feasible. On October 20, 1999, a meeting concerning this project was held between representatives of the Service, the Corps, the applicant, and the applicant's consultant. At that time the Service recommended waiting to initiate section 7 consultation until the City of Carlsbad's screen check of the Environmental Impact Report on the project had been completed. The Service received the Corps' request for initiation of section 7 consultation on August 2. 2000 On August 8. 2000, the Service notified the Corps by letter that we didn't have sufficient information to begin consultation. On August 15, 2000. the Service received from Helix Environmental Planning, Inc. (Helix) the information required to begin consultation. The Service requested that the project be examined for potential effects to least Bell's vireo (Vireo bellii pusiUus: vireo) due to the presence of suitable riparian vegetation on site. Vireo surveys, however, had not been conducted. On September 5. 2000. representatives of the Service, the applicant, and the applicant's biological consultant met to familiarize new Service personnel with the project. The Service and the applicant's consultant visited the project site on September 6, 2000 The areas of tamarisk scrub that had been considered potential vireo habitat were examined, and the Service concluded that these areas were not potential vireo habitat Vireos. therefore, will not be addressed in this biological opinion, as the proposed project is not likely to adversely affect the vireo On October 25, 2000, and again on November 9, 2000, the Service met with the applicant's consultant and discussed measures to compensate for loss of gnatcatcher habitat due to project construction. On November 9, 2000, the Service requested clarification on the amount of viable gnatcatcher habitat on the site. On December 1, 2000, the Service received the area calculations requested on November 9 Froro January 25, 2001 to March 13, 2001, the Service, the City of Carlsbad, the applicant and the applicant's consultant debated the appropriateness of additional measures to compensate for loss of wildlife habitat. On March 13 the Service and the City of Carlsbad agreed not to request an in-Ieiu fee for loss of agricultural lands due to project impacts. On February 23, 2001, the Service received estimates of project impacts to gnatcatcher critical habitat. On March 13, 2001, the Service indicated to the applicant our intent to include a term and condition requiring the applicant to provide undercrossings for wildlife beneath two roads on the site. The applicant requested time to examine the feasibility of providing such undercrossings. On April 6,2001, the Service met with the applicant and the applicant's consultant on-site to examine suitability of existing drainage structures to serve as wildlife undercrossings. 00: ZI iooc vc das Colonel John Carrol! (FWS-SDG-91S) On May 7. 2001. the Corps informed the Service that changes had been requested to calculated areas of Corps jurisdictions! wetlands. Changes to areas of Corps jurisdiction*] wetlands occurred as a result of a January 9, 2001 U.S. Supreme Court decision (Solid Waste Agency of Northern Cook County v. United States Army Corps of Engineers). The Corps requested a field visit with the applicant in late January 2001. The scheduled meeting was rescheduled several times and was eventually held on Apnl 12. 2001 At the request of the applicant and the Corps, a draft of this Biological Opinion was provided to the Corps on May 8, 2001. The Service received comments on the draft from the applicant on June 12, 2001. A letter specifically addressing each of the applicant's comments is attached to this Biological Opinion BIOLOGICAL OPINION DESCRIPTION OF THE PROPOSED ACTION The proposed action is the issuance of a permit under section 404 of the Clean Water Act, that would authorize fill into waters of the U.S., including wetlands, during the construction of the Bressi Ranch housing development. Effects to an unnamed tributary to San Marcos Creek in the City of Carlsbad, San Diego County, California, will occur as a result of the construction and occupation of the Bressi Ranch housing development. The development is proposed to be built on a 585-1-acre parcel immediately south of Paloraar Airport Road and immediately cast of El Camino Real. Much of the site has been dry-farmed for many years. The remaining native vegetation is distributed in approximately 20 scattered irregular patches, mostly located on slopes too steep to farm. The Bressi Ranch Master Plan covers the entire 585 acres of Brcssi Ranch, which is divided into two parcels, a northern and a southern. The northern parcel is 156.4 acres and will be divided into five planning areas, all within the McClellan-Palomar Airport Influence Area. .All five of these planning areas will be designated Planned Industrial. The Planned Industrial areas will contain a combined 2,160.500 square feet of light industrial (40%), research and deve}opment (40%), and office (20%) uses. The 428.6-acre southern parcel will contain seven residential planning areas, one neighborhood commercial planning area, one community facilities/private school planning area, one mixed use area, and seven open space areas. The seven residential planning areas will be developed with a maximum of 523 dwelling units, ranging from low density (approximately one dwelling unit per acre) to medium density (six dwelling units per acre). An additional 100 high-density affordable dwelling units will be constructed in the mixed use area (Planning Area 15). The planned industrial zone (Planning Area 14) will be developed to serve the needs of Bressi Ranch's residents, as will the community facilities zone (Planning Area 13), which may also contain a 70-H no:; I TOfV: ^ das 88£SW98S8:xej 3QDb Colonel John Carroll (FWS-SDG-915) 4 private school. Planning Area 15, in addition to affordable housing, will also include retail and office space, an assisted care facility, and other community facilities such as a daycare The seven open space areas arc within the southern parcel and comprise a total of 192.3 acres. Five of the open space areas will be covered by native vegetation, serving as an open space link within the City of Carlsbad's Habitat Management Plan. Limited grading will occur along the edges of some of these areas, but all graded slopes within open space will be revegctated with Diegan coastal sage scrub Open Space Area 2 will be developed as Bressi Ranch's Village Green with recreational amenities. Open Space Area 7 will be a Recreational Vehicle storage facility Conservation measures The proposed action contains the following conservation measures which will be implemented as part of the project in order to avoid or otherwise minimize potential adverse effects of the action on sensitive and listed species. A total of 185.7 acres will be preserved as biological open space in this development (Rgurc 1). Vegetation types to be conserved include coastal sage scrub, southern mixed chaparral, southern willow scrub, non-native grassland, and disturbed/agricultural habitat (some of which will be partially enhanced with sage scrub vegetative debris and topsoil). Most of the open space will be in the eastern half of the property':' Native vegetation conserved in these areas totals 43.8 acres (Table 1). These areas will be placed under conservation easements and conserved as biological open space in perpetuity. Vegetative debris and the first six inches of topsoil (duff) will be collected from areas of coastal sage scrub that will be impacted by development on Bressi Ranch. This collected material will be distributed on 25 acres of open space on Bressi Ranch that is not currently occupied by native vegetation. Duff application areas will be disced prior to application, and the duff will be spread over the enhancement area to a depth of approximately three inches. Application of duff is expected to accelerate the development of native vegetation on these areas. inrv Colonel John Carroll (HWS-SDG-<m) SJ:N Q. xrau. Colonel John Carroll (FWS-SDG-915) The applicant will acquire 24.5 acres of land occupied by Diegan coastal sage scrub, place a conservation easement over the land, and arrange for its preservation in perpetuity. This land will be located in the City of Carlsbad or the MHCP "core area" indicated in the Public Review Draft of the Multiple Habitat Conservation Plan (SANDAG 2000). The applicant has agreed to acquire such land prior to impacting any native vegetation on Brcssi Ranch. The applicant will work with the Service in selection of appropriate lands. Compensation for impacts to wetland vegetation types is being accomplished by creation of wetland vegetation on areas previously under cultivation, adjacent to existing riparian vegetation on-site. On May 25, 2000, installation of wetland vegetation was completed as described in the Bressi Ranch Draft Conceptual Mitigation Plan, dated January 11. 1999. prepared by Helix Environmental Planning, Inc. If these created wetlands meet success criteria specified in the Draft Conceptual Mitigation Plan before project-related impacts to wetlands occur (such that there is no temporal loss of wetlands), then a 1:1 compensation ratio will be acceptable If a temporal loss of wetlands occurs, the Service will request that additional wetlands be created, enhanced, or conserved. Table I. Vegetation types on Bressi Ranch Vegetation Type cismontane alkali marsh Coastal and valley freshwater marsh southern willow scrub southern willow scrub disturbed/ coastal and valley freshwater marsh mule fat scrub tamarisk scrub streambed Diegan coastal sage scrub Acres On-site 0.14 0.07 5.82 0.29 0.07 4.93 020 65.3 Acres iTnpwVxl 0.02 0.01 0.0 0.29 0.07 3.86 0.18 30.9 Acres Preserved 0.12 0.06 5.82 0 0 1.07 0.02 34.4 10: LI tOOc VC 30DU Colonel John Carroll (FWS-SDG-915) southern, mixed chaparral non-native grassland disturbed/ agriculture developed total 19.9 8.4 470.4 9.5 585.1 10.5 0.7 380.7 9.5 433.6 9.4 7.7 89.72 0 151.5 1. Impacts to all wetland vegetation types will be compensated by creation of riparian habitat on- site. Creation is already in progress. 2. Twenty-five acres of this vegetation type will be enhanced by duff application as described in conservation measures. AcDon Area The action area of a project is the area that is directly and indirectly affected by the proposed project. The Service considers the action area of the Bressi Ranch project to include the entire Bressi Ranch property, the off-site acquisition area, and all areas of native vegetation within 3 kilometers (1.86 miles) of these properties. Three kilometers approximates the average natal dispersal distance of gnatcatchers (Bailey and Mock 1998), thus includes half of the area to which offspring of gnatcatchers on Bressi Ranch are likely to emigrate. According to 50 CFR § 402.02 pursuant to section 7 of the Act. the "action area" means all areas to be affected directly or indirectly by the Federal action and not merely the immediate area involved in the action (e.g.. Corps' junsdictionaJ areas proposed to be filled). Subsequent analyses of the environmental baseline, effects of the action, and levels of incidental take are based upon die action area as determined by the Service. We have described the action area in this consultation to include all areas of native vegetation within 3 kilometers of Bressi Ranch for reasons that will be explained and discussed in the "Effect of the Action" section. Because our action area is a biological determination that must incorporate direct, indirect, and interrelated/interdependent effects to listed species and their habitats, our action area may differ from the scope of analysis used by the Corps under the National Environmental Policy Act as defined in Paragraph 7(b) of Appendix B of 33 CFR 325 STATUS OF THE SPECIES/CRITICAL HABITAT Coastal California GnaCcatcher (Polioplila californica californica) Listing Status The Service listed the coastal California gnatcatcher as threatened on March 30,1993 (Federal TO-Ton/3COU Colonel John Carroll (FWS-SDG-915) g Register 58: 16742). As part of the Federal listing, 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. 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 Habitat Conservation Program (MHCP)) that intend to apply Act standards to activities affecting the gnatcatcher. Under the special rule, incidental take of the gnatcatcher by land-use activities addressed in an approved NCCP Plan would not be considered a violation of section 9 of the Act, provided that the Service determined that the NCCP Plan meets the issuance criteria for an "incidental take" permit, pursuant to section 10(aX2)(B) of the Act and 50 CFR I7.32(b)(2). An interim process was also established whereby jurisdictions actively involved in NCCP planning would be allowed to take up to five percent of the remaining coastal sage habitat for projects that were consistent with the NCCP conservation guidelines. Species Description The coastal California gnatcatcher is a small (length 11 centimeters; weight: 6 grams), long- tailed member of the old-world warbler and gnatcatcher family Sylviidae (American Ornithologists' Union 1998). The bird's plumage is dark blue-gray above and grayish-white below The tail is mostly black above and below. The male has a distinctive black cap which is absent during the winter Both sexes have a distinctive white eye-ring. The coastal California gnatcatcher is one of three subspecies of the California gnatcatcher (Polioptila californica) (Atwood 1991). Prior to 1989, the California gnatcatcher was classified as a subspecies of the Black-tailed gnatcatcher (Polioptila melanura). Atwood (1980, 1988) concluded that the species was distinct from P. melanura, based on differences in ecology and behavior. Recent mitochondria] DNA sequencing confirmed the species-level recognition of the California gnatcatcher (Zink and Blackwell 1998) Distribution Gnatcatchers occur on coastal slopes in southern California, ranging 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 300 meters (m) (984 feet (ft)). Since that time, additional data collected at higher elevation shows that this species may occur as high as 912 m (3,000 ft) and that more than 99 percent of the known gnatcatcher locations occurred below 770 m (2,500 ft) (U.S. Fish and Wildlife Service 2000). Habitat Affinities Gnatcatchcrs typically occur in or near coastal sage scrub habitat. Coastal sage scrub is patchily inn/ \>? da<; RftCqwq^.-xeH AHllHim^) 303U Colonel John Carroll (FWS-SDG-915) 9 distributed throughout (he range of the gnatcatcher, and the gnatcatcher is not uniformly distributed within the structurally and flohstically variable coastal sage scrub community. Rather, the subspecies tends to occur most frequently within California sagebrush (Artemisia ca/i/or7uca)-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 gnatcatchcrs 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 at. 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). Linkages of habitat along linear features such as highways and power-line corridors may be of significant value in linking 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 ei 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 gnatcatchcrs including food source availability, dispersal areas for juveniles, temperature extremes, fire avoidance, and lowered predarjon rate for fledglings. Critical Habiiai On October 24, 2000, the Service published the final determination of critical habitat for the gnatcatcher (Federal Register 65: 63680), including 513.650 acres of Federal, state, local, and private land in Los Angeles, Orange. Riverside, San Bernardino, and San Diego Counties. The Bressi Ranch development site is within critical habitat Map Unit 3: North San Diego County MHCP, which encompasses 7442 acres Primary constituent elements for the gnatcaicher 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 successionaj 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 they may be utilized 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 core areas, including open space and disturbed areas that may receive only periodic use. OT -30Db Colonel John Carroll (FWS-SDG-915) 10 Life History The California gnatcaicher is primarily insectivorous, nonmigratory, and exhibits strong site tenacity (Arwood 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 distribution of arthropods available in their environment. Both adults and young consumed more sessile than active prey items (Burger et al. 1999). The California gnatcaicher 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 5 to 11 hectares per pair and non-breeding season territory size ranged from 5 to J 7 hectares per pair (Preston et al. 1998). During the nonbreedmg 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 ei 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 0.3 to I meter 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 becween late May and late November Nest predation is the most common cause of nest failure (Grishaver ei 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 1/3 of that of the female 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 2000). 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 one 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 (Molothrus ater). Nest parasitism apparently has resulted in earlier nesting dates of the gnatcatcher which may help compensate for the negative affect of parasitism (Panen 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 ei al. 1997). s. das 882?,t7<i98S8:xed AaOibTB^ 3CDb Colonel John Carroll (FWS-SDG-915) 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 gnateatchers banded in San Diego County is reported at less than 3 kilometers (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 gnatcatcher1 s typical dispersal capacity (Bailey and Mock 1998). Juvenile gnatcatchers are apparently able to traverse highly man-modified landscapes for a 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 (Soule 1991) These dispersal corridors may facilitate the exchange of genetic material and provide a path for recolomzation of areas from which the species has been extirpated (Soulc 1991. Galvin 1998). Population Trend The gnatcatcher was considered locally common in the rmd-1940'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, Arwood (1980) estimated that no more than 1,000 to 1,500 pairs remained in the United States. In 1993, at the time the gnaicatcher 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. In 1997. the total number of gnatcatchers in the United States was estimated at 2,899 pairs with two-thirds occurring tn 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 California. 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 (Federal Register 58: 16742). 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 (Wcstman 198la, 198Ib, Harbour and Major 1977), and coastal sage scrub is considered to be one of the most depleted habitat-types in the United States (Kirfcpatrick and Hutchinson 1977, Oljcary 1990). The fragmentation of habitat may artificially increase populations in adjacent preserved habitat; however, these population 1002 Colonel John Carroll (FWS-SDG-915) 12 surpluses may be lost in subsequent years due to crowding 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 contributing to the loss, degradation, and fragmentation of coastal sage scrub is an increase in wildfires due to anthropogenic ignitions. High fire frequencies and the lag period associated with recovery of the vegetation may significantly reduce the viability of affected subpopulations (Dudck and Associates 2000). Furthermore, nest- parasitism by the brown-headed cowbird (Umtt 1984) and nest ptedation threaten the recovery of the gnatcatcher (Atwood 1980. Unitt 1984). Status on-site Gnatcatcher surveys were conducted on Bressi Ranch in July L997. and in June and July 2000 In both years, one pair of gnatcatchers was found, occupying an isolated patch of coastal sage scrub in the south-central portion of the property. In 2000, the birds were also observed to use habitat on the adjacent La Costa Greens property. ENVIRONMENTAL BASEJJNE Regulations implementing the Act (50 CFR §402.02) 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. Also included in the environmental baseline are the anticipated impacts of all proposed Federal projects in the action area that have undergone section 7 consultation, and the impacts of State and private actions which are contemporaneous with the consultation in progress. The proposed project area occurs within the planning area for the Multiple Habitat Conservation Program (MHCP), a subregional plan that will address north coastal San Diego County under the NCCP program. Furthermore, this area occurs within the planning area of the draft Carlsbad Subarca Habitat Management Plan (HMP), which is a subarea plan under the MHCP. The HMP was used as a guideline in formulation of biological resource conservation measures and open space boundaries associated with this project. However, as the HMP is not yet in effect, subarca- wide gnatcatcher conservation measures included in the HMP will not be taken into account in the formulation of this biological opinion. Palomar Airport Road (a high-speed, high-traffic volume four-lane road) borders the property to the north. To the north of Palomar Airport Road is Carlsbad Oaks, and Carlsbad Oaks North: an existing light industry/office complex, and an area of relatively intact native vegetation that is proposed for development into more offices and light industry. Rancho Carrillo lies to the east of Bressi Ranch, and is composed of dense residential development surrounding some narrow patches of native vegetation. Some of these areas of native vegetation are contiguous with proposed preserved areas on Bressi Ranch. To the south the property is bordered by the Villages of La Costa; a housing development which includes some conserved southern maritime chaparral £0:^1 TOOc Vc das 88£Sfri98S8:3CDU Colonel John Carroll (FWS-SDG-9 15) 1 contiguous with a small patch of habitat proposed for conservation in Brcssi Ranch. To the west the property is bordered by El Camino Real (a high-speed, high-traffic volume four-lane road). West of £1 Camino Real is a complex of office buildings, resorts, and other developed lands. EFFECTS OF THE ACTION Effects of the action refer to the direct and indirect effects of an action on the species or critical habitat, together with the effects of other activities that are interrelated and interdependent with that action, that will be added to the environmental baseline. Interrelated actions are those that arc part of a larger action and depend on the larger action for their justification. Interdependent actions are those that have no independent utility apart from the action under consideration. Indirect effects are those that are caused by the proposed action and are later in time, but are still reasonably certain to occur. The BA indicates that the proposed project will result in the direct loss of about 30.9 acres of coastal sage scrub, 10.5 acres of southern mixed chaparral, 0.7 acres of non-native grassland, and 4.6 acres of wetlands and waters of the U.S.. as a result of residential and commercial construction. Measures to minimize the effects of these impacts include the enhancement of currently disturbed areas by distribution of sage scrub vegetation debris and topsoil on approximately 25 acres currently classified as disturbed habitat/agriculture, and acquisition of 24.5 acres of coastal sage scrub habitat within the "core" area that the Service has determined is crucial to gnatcatcher conservation in northern coastal San Diego County. One pair of gnatcatchers will be directly affected by the elimination of the patch of habitat that they currently use on Bressi Ranch. A portion of the proposed project falls within designated critical habitat for the gnatcatcher. Direct impacts to gnatcatcher critical habitat total 70.819 acres (Table 2). However, among the vegetation types that fall within critical habitat boundaries on-site, only Diegan coastal sage scrub and southern mixed chaparral are likely to occupied by gnatcatchers, and the total proposed impact to these two vegetation types is 10.3 acres. On this site, mule fat scrub and southern willow scrub arc unlikely to be used by gnatcatchers, as they are not contiguous with vegetation types normally used for nesting. Table 2. Gnatcatcher critical habitat and proposed impacts on-site vegetation type freshwater marsh Developed Diegan coastal sage scrub acres on-site 0.0410 0.8430 41.243 proposed acres impacted 0.0 0.8430 9.9910 Ml da$ 88£SW98S8:xej AaOitm93a 3CDU Colonel John Canoll (FWS-SDG-915)14 Disturbed habitat/agriculture Mule fat scrub non-native grassland southern mixed chaparral streambed southern willow scrub iota! 134.7860 0.0570 8.0490 9.354 0.0110 5.820 200.204 59.087 0.0570 0.4430 0.3080 0.0 1 10 0.0790 70.819 Effects of project construction and operation (e.g.. noise, dust, fires, potential pollutant dispersal) may extend up to 300 feet from the construction areas. Construction noise is a concern if it is at such a level that it masks vital communication signals (Awbrey 1993)T normal singing behavior, or alters the ability to detect conspecific encroachments, defend territory, attract a mate, detect or warn of the approach of a predator or other interspecific intruder, and/or forage adequately This level is generally accepted to be greater than 60 decibels A-weighted (dBA). It is reasonable to assume that noise from construction and grading equipment may exceed 60 dB Leq at a sufficient distance from the construction sites to affect all of the remaining 33.4 acres of Diegan coastal sage scrub. 9.4 acres of southern mixed chaparral, and 7.7 acres of non-native grassland. Indirect Effects niurainanon of gnatcaicher habitat by night lighting of adjacent developed areas has the potential to disrupt behavior of gnatcatchers, possibly having a deleterious effect. Physiological and behavioral effects of changes in light regime on domestic birds are well-documented Operation of the roads to be constructed on the sue likely will impact gnatcatchers in the action area by greatly increasing their risk of traffic mortality. Numbers of domestic cats on the site are likely to greatly increase due to the proposed action. The deleterious effect of fend and domestic cats on wildlife is extensively documented (Barrati 1995. Liberg 1984). Cats are efficient predators of small animals, including birds, and may kill gnatcatchers. To offset these impacts, the proposed conservation measures include conservation of 24.5 acres of habitat supporting at least 1 pair of gnatcatchers. This land should be either in the City of Carlsbad, or in the MHCP "core" area that the Service has determined is crucial to gnatcatcher conservation in northern coastal San Diego County. 170:303U Colonel John Carroll (FWS-SDG-915) 15 Fragmentation Another significant effect of the Bressi Ranch development on gnatcatchcr populations is habitat fragmentation, which tends to disrupt various ecosystem processes within the remaining habitat. Habitat fragmentation negatively affects abundance and distribution of songbirds, in part by increasing incidence of nest predation and parasitism (Whitcomb et al. 1981, Small and Hunter 1988), and by decreasing probability of recolonizarion of vacant habitat after local extirpation (Crooks et al. in press). Recolonizarion of vacant habitat occurs through natal dispersal (i.e.. gnatcatchers in their first year, leaving their natal territory to establish territories elsewhere). Thus, gnatcatchers dispersing from areas near Brecsi Ranch may recolonize vacant habitat on Bressi Ranch, or vice versa The principle of interaction of local populations of gnatcatchers through natal dispersal underlies the Service's rationale for our definition of the action area in this biological opinion The impact of fragmentation on gnatcatchers must be analyzed with respect to other proposed and existing preserves in Carlsbad. "Linkage D Preserve Planning Area' in the Draft Habitat Management Plan for the City of Carlsbad, provides an opportunity for wildlife dispersal between Core Preserve Planning Areas Nos. 5 and 6. In addition to decreasing the number of "stepping stones" in Linkage D of the proposed Carlsbad HMP, the development of Bressi Ranch will increase nsk to gnatcatchers traveling through or living in Linkage D, due to increased auto traffic and domestic cats. Connectivity between habitat reserve areas is essential for long term maintenance of the viability of the wide range of species, including the gnatcatcher. The increase in risk for gnatcaichers in the open space areas on Bressi Ranch, and the degradation in function and value of this wildlife corridor, is difficult to quantify. Poinsettia Lane and El Fuerte Street may be significant impediments to movement of coyotes (Cards latrans) and bobcats (Lynx rufusY Coyote and bobcat prey includes smaller animals that depredate gnatcatchers and their nests Absence of coyotes and bobcats may thus result in local extirpation of gnatcatchers (Crooks and Soule 1999). The presence of a full complement of resident species is important to the health and viability of a naturally functioning ecosystem. Connectivity between proposed and existing preserve units must be provided through wildlife crossings. Wildlife undcrciossings under Poinsettia Lane and El Fuerte, to ensure that wildlife movement is not precluded, would enhance the long-term viability of the on-site preservation areas as gnatcaicher habitat. CUMULATIVE EFFECTS Cumulative effects include the effects of future State. Tribal, local, or private actions that are reasonably certain to occur in the action area considered in this biological opinion. Future Federal actions that are unrelated to the proposed action are not considered in this section because they require separate consultation pursuant to section 7 of the Act. Lands to the north, west, and east of Bressi Ranch are already developed. The land to the south of Bressi Ranch is part of the proposed Villages of La Costa development, and is slated for construction in the near future. QT -A i?n:^I IfW: flc7 das 88£St^98S8:x£d AaOldT83^ 30DU Colonel John Carroll (FWS-SDG-915) 16 Future development in coastal sage scrub within the City of Carlsbad and the surrounding area will be in accordance with the NCCP Guidelines and the 4(d) special rule. The future MHCP and Carlsbad Subarea Plan for the City arc subject to consultation under section 7 of the Act and therefore do not constitute a cumulative impact. In the event that the Carlsbad Subarea Plan is not approved, and City officials choose noc to participate in the MHCP, proposed hardline conservation areas (e.g., Carlsbad Oaks North business park. Holly Springs, Cantarioi property, and the Carlsbad Raceway) may not be afforded the same protection that the draft subarea plan offers. In that event, conserved gnatcatchers on Bressi Ranch would be considerably more isolated, probability of recolonization after local extirpation would be lower, and likelihood of population persistence of gnatcatchers in Carlsbad would be reduced. The degree of reduced probability of population persistence is not calculable with current data. Unauthorized grading and filling of habitat would continue to affect the long-term viability of these species in a regional context. In recent years, there have been several incidents of illegal grading of habitat within the City of Carlsbad and adjacent lands within unincorporated areas of the County of San Diego. Illegal grading is expected to continue to occur in these areas, affecting the multiple species planning efforts in the area. CONCLUSION After reviewing the current status of the coastal California gnatcatcher. 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 of this species. Although the proposed action will alter critical habitat for the gnatcatcher, we conclude, on the basis of project-related impact avoidance, minimization, and conservation measures, that such alteration will not appreciably diminish the value of critical habitat for the survival and recovery of this listed species, thus the proposed action will not result in the adverse modification of critical habitat for the gnatcatcher The Service reached this conclusion for the following reasons: 1. Impacts to the California gnatcatcher through the direct loss of approximately 30.9 acres of fragmented coastal sage scrub (some of which is occupied by gnatcatchers) will be adequately offset through implementation of the conservation measures, as described in die project description: a. the on-site preservation and management of approximately 34.4 acres of coastal sage scrub b. the enhancement of approximately 25 acres of disturbed habitat. c. the preservation and management of 24.5 acres of coastal sage scrub off-site 1006 172 dgs 882S17Z98S8: Colonel John Carroll (FWS-SDG-915) P These measures will slow the decline of the gnatcatcher and other sage scrub dependent species through the preservation and management of moderate-sized blocks of sage scmb that will be conserved and managed in perpetuity. 2. The number of gnatcatchers expected to be affected by the project is not expected to have a significant effect on the species' overall numbers, distribution, or reproductive potential. This number is a small proportion of the total and regional populations. 3. The anticipated level of take will not preclude the design and implementation of a habitat preserve system in the City of Carlsbad 4. The areas of critical habitat proposed for impact on-site consist of small areas at the periphery of fragments of coastal sage scrub and southern mixed chaparral. The function and value of the remaining critical habitat on-site will be retained. The high value of the gnatcatcher habitat found in the MHCP core area (where the applicant has agreed to acquire gnatcatcher habitat), and the avoidance and minimization measured proposed by the applicant, sufficiently offset the impact to gnatcaicher critical habitat on-site. INCIDENTAL TAKE STATEMENT Section 9 of the Act, and Federal regulations issued pursuant to section 4(d) of the Act. prohibit take of endangered and threatened species, respectively, without a special exemption. Taking is defined as to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or attempt to engage in any such conduct Harm is further defined by the Service to include significant habitat modification or degradation that actually kills or injures a listed species by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering. Harass is defined by the Service as an action that creates the likelihood of injury to a listed species by annoying it to such an extent as to significantly disrupt normal behavioral 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 rhe terms of section 7(b)(4) and section 7(oX2), such incidental taking is not considered to be a prohibited taking under the Act provided that such taking is in compliance with this Incidental Take Statement The measures described below are nondiscretionary and must be undertaken by the Corps and/or applicant, as appropriately defined in the Corps' scope of analysis, in order for the exemption in section 7(o)(2) to apply. The Corps has a continuing duty, subject to their jurisdictional authority, to regulate the activity situated within their scope of analysis and covered by this incidental take statement. Within their scope of analysis, if the Corps (1) fails to assume and implement the terms and conditions or (2) fails to require the applicant to adhere to the terms and conditions through enforceable terms that are added to the permit or grant document, the protective coverage of section 7(pX2) may lapse. Outside the Corps' scope of analysis, if the applicant fails to assume and implement the terms and conditions of the incidental take 81 'd Colonel John Carroll (FWS-SDG-915) 18 statement, the protective coverage of section 7(o)(2) may lapse. To monitor the impacts of incidental take, the applicant must report the progress of the action and its impact on the species to our agency as specified in the incidental take statement [50 CFR § 402.140X3)]. AMOUNT OR EXTENT OF TAKE The Service anticipates that approximately one pair of gnatcatchers could be taken as a result of this proposed action. The take may be in the form of harm and harassment as a result of the removal of 30.9 acres of coastal sage scrub and disturbances to the remaining 34.4 acres of coastal sage scrub and 9.4. acres of southern mixed chaparral during project construction or operation activities. To the extent mat this statement concludes that take of any threatened or endangered species of migratory bird will result from the agency action for which consultation is being made, the Service will not refer the incidental take of any such migratory bird for prosecution under the Migratory Bird Treaty Act of 1918, as amended (16 U.S.C. 703-712), or the Bald Eagle Protection Act of 1940. as amended (16 U-S.C. 668-668d), if such take is in compliance with the terms and conditions (including the amount and/or number) specified herein EFFECT OF THE TAKE In the accompanying biological opinion, the Service determined that this level of anticipated take is not likely to result in jeopardy to the species or destruction or adverse modification of critical habitat. REASONABLE AND PRUDENT MEASURES The Service believes the following reasonable and prudent measures are necessary and appropriate to minimize the impact of take of coastal California gnatcatcher. 1. Take of gnatcatchers, through harm or harassment, shall be minimized to the extent possible by implementation of best management practices. 2. Unavoidable project impacts shall be offset by the implementation of the conservation measures as described in the project description. TERMS AND CONDITIONS In. order to be exempt from the prohibitions of section 9 of the Act, the Corps and the applicant must comply with the following terms and conditions, which implement the reasonable and prudent measures described above. These lerms and conditions are non-discretionary 61'd 90:ZI TOOc t7£ 03$ 88SS17Z98S8: xe j Colonel John Carroll (FWS-SDG-915) 19 1 The Corps and the applicant shall implement reasonable and prudent measure Number 1 through the following terms and conditions: a. No clearing or grubbing activity in coastal sage scrub or southern mixed chaparral shall occur between February 15 to August 31 to avoid impacts to nesting birds. b. If construction will occur within 500 feet of occupied gnatcatcher habitat (considered by the Service to be all coastal sage scrub and chaparral on-site), pre- construction surveys shall be conducted in the adjacent habitat to determine the location of the nesting birds. During construction, no activity will occur within 500 feet of active nests of the gnatcatcher, unless measures arc implemented to minimize the noise and disturbance to those adjacent birds. These measures shall include sound walls that ensure that the hourly L^ sound levels reaching gnatcatcher habitat areas do not exceed the 60 dBA L^, threshold c. Construction limits will be surveyed and fenced with orange snow screen. Employees shall strictly limit their activities and vehicles to the proposed project area(s), staging areas, and routes of travel. d. The applicant shall ensure that aJl equipment maintenance, staging, and dispensing of fuel, oil, coolant, or any other such activities shall occur in designated upland areas. These designated upland areas shall be located in such a manner as to prevent any runoff from entering waters of the United States. e. An employee education program shall be developed. Each employee (including temporary, contractors, and subcontractors) shall receive a training/awareness program within two weeks prior to working on the proposed project They shall be advised of the potential impact to the listed species and the potential penalties for taking such species. At a minimum, the program shall include the following topics: occurrence of the listed and sensitive species in the area, their general ecology, sensitivity of the species to human activities, legal protection afforded these species, penalties for violations of Federal and State laws, reporting requirements, and project features designed to reduce the impacts to these species and promote continued successful occupation of the project area environs. f. The project proponent shall designate a field contact representative (FCR) who shall be responsible for overseeing compliance with protective measures for the listed species. The FCR shall have the authority ro haJt all associated project activities which may be in violation of the terms and conditions of this biological opinion. g. To assure that mere are no impacts beyond those disclosed in this biological opinion, a qualified biologist will be onsite to observe all clearing and grading Oc'd 90-..i I IOOC 176 da$ 88£SP<i98S8:x<?J A$CidT193^ 30DU Colonel John Carroll (FWS-SDG-915) 20 activities in or adjacent to sensitive habitat, and at least once per week after clearing and grading have been completed. 2 The Corps and the applicant shall implement reasonable and prudent measure Number 2 through the following Terms and Conditions: a. The Service hereby incorporates by reference the conservation measure identified in the "Project Description" of this biological opinion into this Incidental Take Statement as terms and conditions b. The applicant shall establish an appropriate financial mechanism which may be an escrow account or a performance bond that would assure that the conservation measures are fully implemented. If the measures are not achieved, this money would be used to implement remedial measures as approved by the Service and the Corps of Engineers. This mechanism must be in place prior to any surface disturbance. c The project proponent shall ensure that long-term management of the off-site preserved habitat areas will occur through the establishment of an endowment account. Amount of the endowment will be determined in consultation with the Service, after preparation of a Property Analysis Record (PAR) to determine management costs and amount of endowment necessary to supply sufficient management funds. Within three months of the acquisition of off-site preservation parcels, a draft management plan shall be developed in coordination with the Service. The plan shall be finalized and implemented within six months. A conservation organization mutually acceptable to the Service and the Corps shall manage the preserved habitat areas in accordance with the management plan. d. The project proponent shall ensure that long-term management of the on-site preserved habitat areas will occur through the establishment of an endowment account. Amount of the endowment will be determined in consultation widi the Service, after preparation of a Property Analysis Record (PAR) to determine management costs and amount of endowment necessary to supply sufficient management funds. Within diree months of the acquisition of off-site preservation parcels, a draft management plan shall be developed in coordination with the Service. The plan shall be finalized and implemented within six months. A conservation organization mutually acceptable to the Service and the Corps shall manage the preserved habitat areas in accordance with the management plan. e. Prior to receipt of a grading permit, the project proponent shall execute and record perpetual conservation easements over both the on-site and off-site preserved habitat areas, in a form acceptable to the Service for biological conservation purposes in favor of the Service, California Department of Fish and Game, or Ic'd 90: zI lOQc \IC Colonel John Carroll (FWS-SDG-915) 21 ocher conservation organization mutually acceptable to the Service and the Corps. f. A report summarizing how the project is in compliance with the reasonable and prudent measures and the terms and conditions of this biological opinion shall be submitted to the Service monthly during the grading phase of construction, and annually for the duration of construction of the project, to demonstrate thai the conservation measures have been achieved. g. The applicant shall construct a fence along the interface between biological open space and developed areas., to exclude cats from the biological open space to the greatest extent practicable. The design of the fence shall be submitted to die Service for concurrence. It will begin at the north end of Open Space Area 3. and extend south along the western border of OS-3, around the southern end of OS-3, to the border of OS-3 and Planning Area PA-15, then continuing north between OS-3 and PA-15 to the intersection of the border between PA-15 and OS-3 and El Fuerte Street. Thus the fence will surround OS-3, except for the border of OS-3 with El Puerte Street (Figure 2). h. The Bressi Ranch development shall comply with all requirements, terms, and conditions in the December, 1999. draft of the Habitat Management Plan for Natural Communities in Carlsbad, pertaining to preserve management and monitoring as described in Section E-6-D on page E-8, concerning Habitat Management of the preserved lands, and specific measures described in section F of the HMP. i. The applicant shall modify the existing 66-inch drainage culverts under the proposed path of El Fuerte Street, and Poinsettia Lane, so that they might serve more effectively as wildlife undercrossings. and thus provide an opportunity for wildlife dispersal between Core Preserve Planning Areas Number 5 and 6. The metal grating barriers at both ends of the pipe under El Fuerte Street must be removed or modified to allow coyotes and bobcats to easily pass through. The flow dissipation structure at the south end of the pipe that runs beneath the service road south of the proposed path of Poinsettia Lane must be replaced with np-rap, or die chain-link fence that runs along die south side of the service road must be provided with a breach at least 1.5 feet high and 1.5 feet wide, to allow easy passage for coyotes and bobcats. The Service's Carlsbad Office is to be notified within three working days should any endangered or threatened species be found dead or injured during this project. Notification must include the date, time, and location of the carcass, and any other pertinent information. Dead animals may be marked in an appropriate manner, photographed, and left on-site. Injured animals should be transported to a qualified veterinarian. Should any treated animals survive, the Service should be contacted regarding the final disposition of the animals. The Service contact person is John TOOc VC das 88£Sfci98S8:xed AoOLtf 10933 30Db Colonel John Carroll (FWS-SDG-915) 22 Martin and may be contacted at the letterhead address or at (760) 431 -9440. The Service retains the right to access and inspect the project site for compliance with the proposed project description and with the terms and conditions of this biological opinion. Any habitat destroyed that is not in the identified project footprint should be disclosed immediately to the Service for possible reinitiation of consultation. Compensation for such habitat loss will be requested at a minimum ratio of 5:1. The Service believes that no more than one pair of gnatcalchers will be incidentally taken as a result of the proposed action The reasonable and prudent measures, with their implementing terms and conditions, are designed to minimize the impact of incidental take that might otherwise result from the proposed action. If, during the course of the action, this level of incidental take is exceeded, such incidental take represents new information requiring reinitiation of consultation and review of the reasonable and prudent measures provided. The Federal agency must immediately provide an explanation of the causes of the taking and review with the Service the need for possible modification of the reasonable and prudent measures. £c-d iO'-il 1OK Ml das 88£SW.98S8:«d AaOi«~in93a 30DU Colonel John Canx>ll (FWS-SDG-915)23 Rgure2. Location erf fence. Fence: 176 '1006 VC da$30Db Colonel John Carroll (FWS-SDG-915) 24 CONSERVATION RECOMMENDATIONS Section 7(a)(l) of the Act directs Federal agencies to utilize their authorities to further the purposes of the Act by carrying out conservation programs for the benefit of endangered and threatened species. Conservation recommendations are discretionary agency- activities to minimize or avoid adverse effects of a proposed action on listed species or critical habitat, help implement recovery plans, or to develop information. 1 The Service recommends the establishment of a community outreach/education program to increase awareness by residents and users of the Bressi Ranch development of the natural resource values of the open space preserved on the Bressi Ranch property, its functional relationship to the network of natural resource preserves in the City of Carlsbad and the MHCP area, and ways they might minimize impacts to their neighborhood preserve and ensure its function and value to wildlife in perpeouty. In order for the Service to be kept informed of actions minimizing or avoiding adverse effects or benefitting listed species or their habitats, the Service requests notification of the implementation of any conservation recommendations. REINITIATION NOTICE This concludes formal consultation on the Bressi Ranch development project outlined in the consultation request. As provided in 50 CFR §402.16, reinitiation of formal consultation is required where discretionary Federal agency involvement or control over the action has been retained (or is authorized by law) and if: (1) the amount or extent of incidental take is exceeded: (2) new information reveals effects of the agency action that may affect listed species or criticaJ habitat in a manner or to an extent not considered in this opinion; (3) the agency action is subsequently modified in a manner that causes an effect to listed species or critical habitat that was not considered in this opinion; or, (4) a new species is listed or critical habitat is designated that may be affected by the action. In instances where the amount or extent of incidental take is exceeded, any operations causing such take must cease pending reinitiation. If you have any questions regarding this biological opinion, please contact John Martin at (760) 431-9440. Sincerely >Nancy Gilbert Assistant Field Supervisor bc-d 80: ZI lOOd" ttf das 88£SW98S8:xej AdOlbTB^ 30Db Colonel John Carroll (FWS-SDG-915) 25 cc: Barry Jones, Helix Environmental on- IT inn- n7 dac ««CC;i7^q«<^:x9H Colonel John Carroll (FWS-SDG-915) 26 LITERATURE CITED American Ornithologists' Union. 1998. Checklist of North American Birds. Seventh Edition. American Ornithologists' Union. Washington. D.C. 829 pages. Atwood, J. 1980. The United Stales distribution of the California black-tailed gnatcatcher. Western Birds 11:65-78 . 1988. Speciation and geographic variation in black-tailed gnaicatchers. Ornithological Monographs No. 42. American Ornithologists' Union. Washington, D.C, _. 1990. Status Review of the California Gnatcatcher (Polioptilla califomica). Manomet Bird Observatory, Manomet, Massachusetts .. 1991. Subspecies limits and geographic patterns of morphological variation in California gnatcatchcrs (Polioptila califomica). Bulletin of the Southern California Academy of Sciences 90: 118-133. . and J. S. Bolsinger. 1992. Elevational distribution of California gnatcatchen in the United States. J. Field Ornithology 63: 159-168. Bailey. E . A. And P. J. Mock. 1998. Dispersal Capability of the California gnatcatcher: A landscape analysis of distribution data. Western Birds 29: 351-360. Barbour, M. and J. Major 1977. Terrestrial Vegetation of California. John Wiley and Sons. New York Barratt. DG. 1995. Using theory and scientific experience to assess the impact of house-based domestic cats Felis cams (L.) on prey populations and community structure. Proceedings of the Third National Conference on Urban Animal Management in Australia. Canberra, pp. 147-156. Braden. G. T, R L. McKernan, and S. M. Powell. 1997. Effects of nest parasitism by the brown- headed cowbird on nesting success of the California gnatcatcher. Condor 99: 858-865. Burger J. C, M. A. Patten. J. T. Roienberry, and R. A. Redak. 1999. Foraging ecology of the California gnatcatcher deduced from fecal samples. Oecologia (Berlin) 120: 304-310. Campbell, Kurt F., R. A. Erickson. W. E. Haas, and M. A. Patten. 1998. California Gnatcatcher use of habitats other than coastal sage scrub: conservation and management implications. Western Birds 29(4): 421-433. : xe4 A>Di i-nrmx "rnt-t Colonel John Carroll (FWS-SDG-915) 27 Crooks, K. R., and M. E. Soule. 1999. Mesoprcdator release and avifaunal extinctions in a fragmented system. Nature 400:563-566. , Andrew V. Suarez, Douglas T. Bolger, and Michael Soule. Extinction and recolonization of birds on habitat islands. In press. Dudek and Associates. 2000. Comprehensive species list. In: Understanding the plants and animals of the western Riverside County MSHCP [http://ecoregion.ucr.edu/mshcp/irKfcx.htmJ). Famolaro, P. And J. Newman. 1998. Occurrence and management considerations of California gnatcatchers along San Diego County highways. Western Birds 29: 447-452. Galvin. J. P. 1998. Breeding and dispersal biology of the California gnatcatcher in Central Orange County. Western Birds 29: 323-332. Grishaver, M. A. P. J. Mock, and K. L. Preston. 1998. Breeding behavior of the California gnatcatcher in southwestern San Diego County. California. Western Birds 29: 299-322. Kirfcpatnck. J.. andC. Hutchinson. 1977 The community composition of California coastal sage scrub. Vegetaiio 35:21-33. Liberg O. Food habits and prey impacc by feral and house-based domestic cats in a rural area in southern Sweden. J Mammal 1984:65:424-432. Mock, P.J.. B. L. Jones, and J. Konecny. 1990. California Gnatcatcher Survey Guidelines. ERC Environmental and JEnergy Services Co. OTjeary, J. 1990. Californian Coastal Sage Scrub: General Characteristics and Considerations for Biological Conservation. Pages 24-41. IN: Endangered Plani Communities ofSouih- em California. (A. Schoenherr, ed.}. Southern California Botanists Special Publication Number 3. Patten, M. A. And K. F. Campbell. 1998. Has brood parasitism selected for earlier nesting in the California gnatcatcher? Western Birds 29:290-298. Preston, K. L., M. J. Mock. M. A. Grishaver, E. A. Bailey, and D. F. King. 1998. California gnatcatcher territorial behavior. Western Birds. 29:242-257 Scott, T. A. 1993. Initial effects of housing construction on woodland birds along the wildland urban interface. In Interface between Ecology and Land Development in California. Edited by J. E. Keeley. Southern Catifomia Academy of Sciences, Los Angeles. Ton- r,7 rtec «»CCf7^QftC«: XP-i Colonel John Carroll (FWS-SDG-915) 28 Small, M.F. and M.L. Hunter. 1988. Forest fragmentation and avian nest predaiion in forested landscapes. Journal of Wildlife Management 52:123-126. Sockman, K.W. 1997. Variation in life-history traits and nest-site selection affects risk of nest predation in the California gnatcatcher. Auk 114: 324-332. 1998. Nest attendance by male California gnateaichers. J. Field Ornithology 69:95- 102 Soule. M. E. 1991. Land use planning and wildlife maintenance, guidelines for conserving wildlife in an urban landscape. Journal of the American Planning Association 57: 313- 323. Unitt, P. 1984. The birds of San Diego County. San Diego Society of Natural History. Memoir 13. San Diego, California. 276pp. U.S. Fish and Wildlife Service. 19%. Biological Opinion 1-6-93-F-37R1 on the Effects of Implementing the 4(d) Special Rule for the Coastal California Gnatcatcher. October 18. Carlsbad Fish and Wildlife Field Office. Carlsbad, California. Weaver. K. L. 1998. Coastal sage scrub variations of San Diego County and their influence on the distribution of the California gnatcatcher. Western Birds 29: 392^05. Westman. W. 198la. Diversity relations and succession in California coastal sage scrub. Ecology 62: 170-184. . 1981 b. Factors influencing the distribution of species of California coastal sage scrub. Ecology 62:439-455. Whitcomb, R.R., C. S. Robbms, J. F. Lynch, B.L. Whitcomb, M. K. Klimkiewicz, and D Bystrak. 1981. Effects of forest fragmentation on avifauna of the eastern deciduous forest. Pages 125-205 In: Forest island dynamics in man-dominated landscapes. R. L. Burgess and D. M. Sharpe (eds.) Springer-Veriag, New York, New York. Zink. R. M.. and R. C. Blackwell. 1998. Molecular systematic* and biogeography of and land gnatcatchers (Genus Polioptila) and evidence supporting species status of the California gnatcatcher (Polioptila californica). Molecular Phylogcneiics and Evolution 9: 26-32. xp -