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HomeMy WebLinkAboutCT 95-05; Emerald Ridge East; Tentative Map (CT) (5)I I I I I I BIOLOGICAL SURVEY AND REPORT * FOR _ EMERALD RIDGE - EAST I I | Prepared for: I MSP Californica LLC. 650 S. Cherry Street, Suite 435 Denver, Colorado 80222 I I Prepared by: * Brian F. Mooney Associates _ - 9903-B Businesspark Avenue I San Diego, California 92131-1120 I September 1995 I I TABLE OF CONTENTS Section Page I. SUMMARY 1 II. INTRODUCTION 1 A. Project Description and Location 1 B. Physical Characteristics 2 III. METHODS 2 IV. RESULTS 5 A. Botany 5 B. Zoology 5 C. Sensitive Species 11 D. Sensitive Habitats 14 E. Habitat Evaluation 14 V. IMPACT ANALYSIS 15 A. Assumptions and Assessment Guidelines 15 B. Project Impacts 16 VI. MITIGATION MEASURES 18 A. Mitigation Program 18 VII. REFERENCES 19 Biological Survey and Report for Emerald Ridge - East 1 1 1 1 1 1 • 1 1 • 1 1 1 1 1 1 1 1 • 1 LIST OF FIGURES Number Title 1 Regional Location Map 2 Vicinity Map 3 Biological Resources Map 4a Biological Impacts Map 4b Biological Impacts Map LIST OF TABLES Number Title 1 Plant Species Observed at Emerald Ridge - East 2 Animal Species Observed at Emerald Ridge - East 3 Emerald Ridge - East Impacts Biological Survey and Report for Emerald Ridge - East Page 3 4 6 17 Map pocket Page 7 10 16 11 I. SUMMARY The proposed Emerald Ridge - East project is a Tentative Map (TM) to divide approximately 27.4 acres into 60 residential lots and three open space lots. The project site is located hi the City of Carlsbad, in northern San Diego County, approximately 500 feet south of Palomar Airport Road and 1.5 miles east of Interstate 5. Access to the TM will be via Hidden Valley Road. The majority of the site (25.73 acres) is disturbed as a result of agricultural activities. The property supports two native habitat types: Diegan coastal sage scrub (1.47 acres including 0.15 acre of disturbed sage scrub) and wetland vegetation (0. 17 acre). In addition, there is a drainage channel (0.03 acre) that is vegetated with upland plant species in some areas and unvegetated in other areas. No Federally or State listed Threatened or Endangered plant species were observed during the field surveys, however, there is a high potential for two sensitive plant species (ashy spike-moss and western dichondra) to occur within the property boundaries. Three sensitive bird species (turkey vulture, northern harrier, and California gnatcatcher) were observed on-site during the field surveys. No sensitive reptile species were observed during the surveys, however, two sensitive reptile species (San Diego coast horned lizard and orange- throated whiptail) would be expected to occur in the sage scrub and chaparral on-site. Implementation of the Tentative Map would impact 19. 17 acres of disturbed land and 0.^9 acre of sage scrub (including 0.15 acre of disturbed sage scrub) for a total of 19.76 acres. The loss of disturbed land would not be considered a significant loss. Impacts to sage scrub would be considered a significant impact due to the sensitivity of the habitat and the presence of a Federally listed species (California gnatcatcher). Impacts to 0>59cacre of sage scrub would be mitigated by the purchase of O.'TjS'acre of sage scrub within a mitigation bank preserve or by the creation of 0.<pf acre of habitat in the disturbed area located in the southeastern corner of the property. Implementation of the Emerald Ridge - East project would result hi the preservation of 7.64 acres in open space. This would include 0.88 acre of sage scrub, 0.17 acre of wetland vegetation, 0.03 acre of drainage channel, and 6.56 acres of disturbed land. II. INTRODUCTION A. Project Description and Location The proposed Emerald Ridge - East project is a Tentative Map (TM) to divide approximately 27.4 acres into 60 residential lots and three open space lots. The project site is located in the City of Carlsbad, in northern San Diego County, approximately 500 feet south of Palomar Biological Survey and Report for Emerald Ridge - East T I I I I I I I I I I I I I I I I I I I Airport Road and 1.5 miles east of Interstate 5 (Figure 1). Access to the TM will be via Hidden Valley Road. B. Physical Characteristics The majority of the property is on west-southwest facing slopes (Figure 2). Elevation ranges from approximately 70 feet above mean sea level (AMSL) along the northern boundary of the property to 210 feet AMSL along the eastern boundary of the site. Soils found on the study site include Las Flores loamy fine sand with 15-30% slopes and Gaviota fine sandy loam with 9-30% slopes (Bowman 1973). The surrounding land uses include fallow agricultural areas to the north and south. Also to the north is Encinas Creek, beyond which is Palomar Airport Road. West of the project site is a north-south drainage and beyond it an agricultural field. To the east are residences and open areas. III. METHODS An initial biological resource inventory was conducted to map the vegetation communities within the project boundaries, survey the wildlife present, and to search for the presence of sensitive plant and annual species. This inventory, originally called Hidden Valley Estates (Mooney 1994) also covered resources within the adjacent Emerald Ridge - West development. Resources were mapped on a 1 inch =100 feet scale topographic map. The initial survey was conducted on June 30, 1994 between the hours of 1300 and 1600 by L. Embree and G.T. Baird. The weather at the beginning of the survey consisted of partially clear skies with a temperature near 80° F and a light wind. By the end of the survey, the temperature was unchanged despite an increase hi wind and cloud cover. A second field survey was conducted on September 16, 1994 by G.T. Baird between the hours of 0800 and 0900 for additional vegetation mapping. A third field survey was conducted on July 29, 1995 by G.T. Baird between the hours of 0700 and 1000 to assess any changes to the biological resources. For this report, previous biological studies for the project site were reviewed (RECON 1991; Mooney 1991, 1994, and 1995; and Dudek 1995. The following references or field guides were used for the biological resource inventory: habitats, Holland 1986; flora, Bailey 1924, Munz 1974, Beauchamp 1986, and Hickman 1993; birds, Binford 1986 and DeBenedictis 1989; mammals, Jones, et al. 1982 and Jameson and Peelers 1988; reptiles, Jennings 1983. Biological Survey and Report for Emerald Ridge - Hast I I I I I I I I I I I I I I I I I I I ORANGE COUNTY CAMP JOSEPH H.PENDLETONU.S.M.C.B. Project Location ESCONDIDO 78 TIONALCITY n CHULA VISTA PACIFIC BEACH POINT LOMA Brian F. Mooney Associates 10 Miles Regional Location Map Figure 1 Emerald Ridge-East Brian F. Mooney Associates 1000' 2000' Vicinity Map Figure 2 Emerald Ridge - East I I I I I I I I I I I I I I I I I I I IV. RESULTS A. Botany The majority of the vegetation on the site is disturbed as a result of previous use as crop land but has been allowed to lay fallow for years except for periodic discing (Figure 3). A few weedy, non-native plant species were observed scattered around the fallow field including black mustard (Brassica nigrd), wild oat (Avena sp.), wild radish (Raphanus sativus), bromes (Bromus sp.), and sweet fennel (Foeniculum vulgare). These species also occur in two large patches near the northern and the eastern boundaries. There are approximately 25.73 acres of disturbed land. The property supports two native habitat type: Diegan coastal sage scrub (sage scrub) and wetland vegetation (Figure 3). Sage scrub consists of low woody subshrubs, many of which are summer deciduous. This vegetation community typically is found on dry sites, such as steep, south and southeast facing slopes. Sage scrub occurs in two small patches within the agricultural area adjacent to the eastern property boundary. A portion of one of the patches is disturbed, with a higher percentage of wild oat and bromes. Sage scrub also occurs in the southern portion of the site, extending off-site to the west. Dominant species observed include California sagebrush (Artemisia californicd), lemonadeberry (Rhus integrifolid), black sage (Salvia melliferd) and coyote bush (Baccharis pilularis var. consanguined). There are approximately 1.47 acres of sage scrub including 0.15 acre of disturbed sage scrub. Wetland vegetation was identified in the Enemas Creek channel along the northern boundary of the property in a wetland delineation conducted by Dudek & Associates (1994). The vegetation was dominated by pampas-grass (Cortaderia dioica) with a few scattered individuals of arroyo willow (Salix lasiolepis). There is a total of 0.17 acre of wetland vegetation on the project site. Dudek (1995) also surveyed the northeast-southwest drainage in the southern portion of the property. The drainage channel consisted of unvegetated areas as well as areas with vegetation that would be characterized as upland species, such as coyote bush, tree tobacco (Nicotiana glauca), California sagebrush, and lemonadeberry. There is 0.03 acre of drainage channel within the project boundaries. A total of 62 plant species (including 30, or 49% non-native species) were detected during the initial inventory hi 1994 (Table 1). The high number of non-native species observed indicates the high level of disturbance from agricultural activities. Due to the tune of the year the survey was conducted, some herbaceous annual plants may have been present, but were not detected. B. Zoology This section discusses the wildlife associated with each vegetation community, as presented above. A total of 19 wildlife species were observed during the 1994 inventory (Table 2). The number of wildlife species observed during the field surveys was limited due to the tune of the year the surveys were conducted, the weather conditions, and the behavior of individual species. Biological Survey and Report for Emerald Ridge - East I I I I I I I I I I I I I I I I I I I I Diegan Coastal Sage Scrub Disturbed Sage Scrub Disturbed Riparian Vegetation (RV) Drainage Channel California Gnatcatcher Project Boundary Brian F. Mooney Associates 200'400' Biological Resources Map Figure 3 Emerald Ridge-Easc I I I I I I I I I I I I I I I I I I I Table 1. Plant Species Observed at Emerald Ridge - East Species1 Habitat2 DICOTYLEDONEAE AIZOACEAE - Carpet-weed Family *Carpobrotus edulis, hottentot-fig Di *Mesembryanthemum crystallinum, crystal ice plant Di ANACARDIACEAE - Sumac Family Malosma laurina, laurel sumac SS.MC Rhus integrifolia, lemonadeberry SS,MC Toxicodendron radicans ssp. diversilobum, poison oak SS,RS,MC APIACEAE - Carrot Family *Foeniculum vulgare, sweet fennel Ag,RS ASTERACEAE - Sunflower Family Ambrosia psilostachya, western ragweed Ag.RS Artemisia californica, California sagebrush SS Baccharispilularis var. consanguinea, coyote brush SS,Di,RS Baccharis salicifolia, mule-fat RS *Centaurea melitensis, tocalote Di *Conyza canadensis, common horseweed Di,RS Encelia californica, California encelia SS Eriophyllum confertiflorum var. confertiflorum, golden yarrow SS Gnaphalium bicolor, bicolor cudweed SS Hemizonia fasciculata, fascicled tarplant Ag,SS,Di Isocoma menziesii var. vernonioides, coastal goldenbush SS,Di,RS *Picris echioides, bristly ox-tongue Di *Sonchus asper ssp. asper, spiny-leaf sow-thistle Ag *Xanthium stnanarium, cocklebur RS BORAGINACEAE - Carrot Family Heliotropium curvassavicum, heliotrope Ag,Di BRASSICACEAE *Brassica nigra, black mustard SS.Ag *Raphanus sativus, wild radish Ag,Di CACTACEAE - Cactus Family *Opuntiaficus-indica, Indian fig SS Opuntia littoralis, coastal prickly-pear . . SS CAPPARACEAE - Caper Family Cleome isomeris, bladderpod SS Biological Survey and Report for Emerald Ridge - East 1 1 1 1 • 1 1 1 • 1 Table 1. Plant Species Observed at Emerald Ridge - East C " 1 CAPRIFOLIACEAE - Honeysuckle Family Sambucus mexicana, desert elderberry CHENOPODIACEAE - Goosefoot Family *Chenopodium album, lamb's quarters *Salsola iberica, Russian thistle EUPHORBIACEAE - Spurge Family *Ricinus communis, castor-bean FAGACEAE - Oak Family Quercus dumosa, Nuttall's scrub oak GROSSULARIACEAE - Currant Family Ribes spedosum, fuchsia-flower gooseberry LAMIACEAE - Mint Family *Marrubium vulgare, horehound Salvia apiana, white sage Salvia mellifera, black sage MALVACEAE - Mallow Family Malacothamnus fasdculatus vai.fasciculatus, bush mallow NYCTAGINACEAE - Four O'clock Family Mirabilis calif arnica, wishbone plant POLYGONACEAE - Buckwheat Family Eriogonum fasticulaltum ssp. fasticulatum, flat-top buckwheat *Rumex crispus, curly dock PRIMULACEAE - Primrose Family *Anagallis arvensis var. arvensis, scarlet pimpernel ROSACEAE - Rose Family Heteromeles arbutifolia, toyon RUTACEAE - Citrus Family Cneoridium dumosum, coast spice bush SALICACEAE - Willow Family Salix goodingii, black willow Salix lasiolepis, arroyo willow Biological Survey and Report for Emerald Ridge - Hast (Continued) Habitat2 SS.MC Di.RS Ag.SS.Di RS MC SS.MC Ag,Di,RS MC SS ss SS ss RS Ag RS MC RS RS 8 I I I I I I I I I I I I I I I I I I I Table 1. Plant Species Observed at Emerald Ridge - East (Continued) Species1 Habitat2 SCROPHULARIACEAE - Figwort Family Mimulus aurianticus, monkey-flower SS SOLANACEAE - Nightshade Family Datura wrightii, jimson weed Ag *Nicotiana glauca, tree tobacco Ag TAMARICACEAE - Tamarisk Family Tamarix sp., tamarisk RS Urticaceae - Nettle Family Urtica dioica ssp. holosericea, hoary nettle RS MONOCOTYLEDONEAE CYPERACEAE - Sedge Family *Cyperus alternifolius, African umbrella-plant Di,RS POACEAE - Grass Family *Avena sp., wild oat SS,Di *Avena sativa, cultivated oats Di *Bromus diandrus, common ripgut-grass SS.Di *Bromus mollis, soft chess SS.Di *Bromus rubens, foxtail chess SS,Di *Cortaderia dioica, pampas-grass Di,RS *Cortaderiajubata, Atacama pampas-grass Di,RS *Cynodon dactylon, common Bermuda grass Di,RS *Echinochloa crus-galli, barnyard grass Di *Polypogon monspeliensis,Tabbitfoot beardgrass RS * Denotes non-native taxa.1 Nomenclature from Bailey (1924), Munz (1974), Beauchamp (1986) and Hickman (1993). 2 Habitats: Ag = Agricultural Fields Di = Disturbed MC = Southern Mixed Chaparral RS = Disturbed Southern Willow Scrub SS = Diegan Coastal Sage Scrub Biological Survey and Report for Emerald Ridge - East I I I I I I I I I I I I I I I I I I I Table 2. Animal Species Observed at Emerald Ridge - East Common Name turkey vulture black-shouldered kite northern harrier American kestrel California quail greater roadrunner black phoebe Cassin's kingbird bushtit California gnatcatcher wrentit northern mockingbird rufous-sided towhee California towhee rufous-crowned sparrow house finch lesser goldfinch Common Name California ground squirrel cottontail rabbit Birds Scientific Name1" Cathartes aura Elanus caeruleus Circus cyaneus Falco sparverius Callipepla califomica Geococcyx californianus Sayomis nigricans Tyrannus vociferans Psaltriparus minimus Polioptila califomica Chamaea fasciata Mimus polyglottos Pipilo erythrophthalmus Pipilo crissalis Aimophila ruficeps Carpodacus mexicanus Carduelis psaltria Mammals Scientific Name'4' Spermophilus beecheyi Sylvilagus auduboni Habitat0* O O O 0 SS Ag Ag SS.RV SS.RV SS SS SS.RV SS SS SS Ag.SS.RV SC.MC Habitat01 AG.SS SS Abundance'31 e e e e d e d e c d e e e e e b d Evidence sighted scat, sighted (1) (2) (3) (4) Nomenclature from Binford 1986 and DeBenedictis 1989. Habitats: Ag = Agricultural Fields RV = Riparian Vegetation MC = Southern Mixed Chaparral SS = Diegan Coastal Sage Scrub O = Overhead Abundance indicated by relative abundance: a = abundant - 20+ d = uncommon - 3-5 b = common - 10=20 e = rare - 1 or 2 c = occasional - 5-10 Nomenclature from Jones, et al. 1982. The discussion of wildlife observed is supplemented by those species expected to occur based on previous studies. Diegan Coastal Sage Scrub. Common wildlife species observed in the sage scrub include California quail (Callipepla califomica), wrentit (Chamaea fasciata), California towhee (Piplo crissalis) and house finch (Carpodacus mexicanus). Most of these species were detected only on the Emerald Ridge - West TM during the initial 1994 survey. However, California Biological Survey and Report for Emerald Ridge - East 10 I I gnatcatchers (Polioptila California) were detected in the sage scrub on-site near the southern boundary and off-site to the west during a survey in July of this year. California gnatcatchers • were also detected northwest of the site as well as north of the residential development to the east of the project site (Mooney -1994). Observations of the species also occurred within the sage scrub off-site to the west during the 1991 REGON survey of the area. This species is • regarded as sensitive and will be discussed hi more detail in the Sensitive Species section. Audubon's cottontail (Sylvilagus auduboni) scat was also observed in the sage scrub. • Various reptile species such as the orange-throated whiptail (Cnemidophorus hyperythrus) and San Diego coast horned lizard (Phrynosoma coronatum blainvillei) were not seen but would be expected to occur in this community.I I I I I I I I I I I I I I Wetland Vegetation. This community typically provides a structurally diverse habitat and varied food supply for a number of wildlife species. Only a few bird species were observed, including Cassin's kingbird (Tyrranus vociferans), bushtit (Psaltriparus minimus), northern mockingbird (Mimuspolyglottos) and house finch (Carpodacus mexicanus). Raptors. Several raptor species were detected flying overhead including turkey vulture (Cathartes aura), black-shouldered kite (Elanus caeruleus), northern harrier (Circus cyaneus) and American kestrel (Falco sparverius). They would be expected to forage over most of the project site. C. Sensitive Species Plant and animal species are considered sensitive if they have been listed as such by federal or state agencies, or one or more special interest groups such as the California Native Plant Society (CNPS) (Skinner and Pavlik 1994). The California Department of Fish and Game (CDFG) publishes separate comprehensive lists for plants and animals through the Natural Diversity Data Base (CDFG 1995a and 1994). CDFG also publishes Rarefmd searches (1995b). These lists include taxa officially listed by California or the Federal Government as Endangered, Threatened, or Rare, and candidates for state or federal listing. Candidate Species are considered either Category 1 or 2. Category 1 species are those taxa for which the United States Fish and Wildlife Service (USF&WS) has sufficient biological information to support a proposal to list as Endangered or Threatened. Category 2 species are those taxa for which existing information may warrant listing, but substantial biological information to support a proposed rule is lacking. These categories can be applied to both plants and animals. The animal list also includes Fully Protected Species and Species of Special Concern. The CNPS also provides a comprehensive listing of plant species. Their sensitivity evaluation of a species is based on its rarity, endangerment, and distribution (Skinner and Pavlik 1994). Number values are assigned to these categories which, when considered together, are the basis for placement on one of four lists: List IB: Plants Rare, Threatened, or Endangered in California and Elsewhere; List 2: Plants Rare, Threatened, or Endangered hi California, But More Common Elsewhere; List 3: Plants About Which We Need More Information - A Review Biological Survey and Report torEmerald Ridge - bast 11 I I I I I I I I I I I I I I I I 1 I I List; and List 4: Plants of Limited Distribution - A Watch List. For the purposes of this report, species on state or federal lists or CNPS Lists IB and 2 have been of prime consideration. Plants No Federally or State listed Threatened or Endangered plant species were observed during any of the biological studies conducted on the site. While not seen during the present study, ashy spike-moss (Selaginella cinerascens) was reported observed off-site near the southeastern corner of the property in sage scrub (RECON 1991). There is a high potential for this species to also occur on-site. Ashy spike-moss is a CNPS List 4 species that is declining due to urban expansion. An additional twelve sensitive plant species have been reported in the vicinity (CDFG 1994). There is a high potential for western dichondra (Dichondra occidentalis) to occur on-site. The preferred habitats of this species are chaparral, sage scrub and post-burn habitats. Western dichondra is a CNPS List 4 species that is slowly declining in coastal southern California. The remainder of the sensitive plant species reported hi the vicinity have a low potential of occurring on site. Habitat for some of the species does not occur on-site: Del Mar mesa sand- aster (Corethrogyne filaginifolia var. linifolid), thread-leaved brodiaea (Brodiaea filifolid), Nuttall's lotus (Lotus nuttallianus), San Diego thornmint (Acanthomintha ilicifolia), and Del Mar manzanita (Arctostaphylos glandulosa ssp. crassifolia). Others would have been detected if present on-site: California adolphia (Adolphia californicd), Encinitas baccharis (Baccharis vanessae), wart-stemmed ceanothus (Ceanothus verrucosus), summer holly (Comarostaphylis diversifolia ssp. diversifolid), Engelmann oak (Quercus engelmannii) and San Diego barrel cactus (Ferocactus viridescens). Wildlife Birds. The Audubon Society has provided sensitive bird listings on the national and local level. The Blue List (Tate 1986) is a national listing of sensitive birds which is an early warning system for sensitive birds. In addition to reporting on Federal action for the listed species, the list separates the species into those of national concern (The Blue List) and those of local concern. The local Audubon Society published a list of sensitive bird species for San Diego County (Everett 1979). This listing categorizes species as Threatened, Declining, or Sensitive. Threatened status is accorded to those species or subspecies which have undergone dramatic, non-cyclical, long-term population declines, to the point where the situation has reached the critical level throughout their range. Declining status is given to species whose local breeding populations have been steadily reduced, or in some cases extirpated. Sensitive species are those for which declines have not been documented, but are regarded as such because of: (a) ex- tremely localized or limited distribution, (b) sensitivity to disturbance, (c) actual or impending destruction of essential habitat, or (d) lack of sufficient data on current or past status which significantly increased the potential for serious reduction of a local population. Biological Survey and Report for Emerald Ridge - East 12 Three sensitive bird species were observed during the surveys: turkey vulture, northern harrier, and California gnatcatcher. The turkey vulture and northern harrier were observed flying overhead and most likely forage over the agricultural fields on and adjacent to the site. The turkey vulture is listed by Everett (1979) as declining and is considered sensitive by the Blue List (Tate 1986). The northern harrier is also on the Blue List (Tate 1986) and is a State Species of Special Concern. The most publicized sensitive species inhabiting sage scrub is the California gnatcatcher (gnatcatcher). The gnatcatcher is a State Species of Special Concern. In March 1993, the USF&WS listed the gnatcatcher as a Threatened species under the Endangered Species Act. This action was reversed by the courts hi April 1994. However, the gnatcatcher was relisted as a Federal Threatened species in June 1994. California gnatcatchers were detected in the sage scrub on-site near the southern boundary and off-site to the west during a survey hi July of this year. California gnatcatchers were also detected northwest of the site as well as north of the residential development to the east during earlier surveys (Mooney 1994). Observations of the gnatcatcher in sage scrub off-site to the west have also been reported hi previous biological studies (RECON 1991, Mooney 1991). The burrowing owl (Athene cunicularid) and/or burrows were not observed during any of the surveys, but historically has been reported near Palomar Airport (Unitt 1984). The burrowing owl is considered a State Species of Special Concern because of impacts to its habitat, grasslands and agricultural lands, in the form of grazing and development. Burrowing owls typically use burrows created by ground squirrels or other fossorial mammals, but may also use man-made structures, such as cement culverts or openings beneath cement or asphalt pavement (CBOC 1993). The burrowing owl is not expected to occur on-site. Reptiles and Amphibians. Analysis of sensitive reptiles and amphibians, beyond the state and federal lists, is provided by the San Diego Herpetological Society (SDHS). This group has published a listing of endangered and threatened reptile species of San Diego County (1980) and a status report for indigenous amphibians (1980a). For reptiles, an endangered species is defined to be one whose population and habitat distribution have been reduced to such a widespread extent that the species is unable to reproduce at a normal rate and is imminently near extinction throughout the majority of its remaining distribution in San Diego county. A threatened species is defined to be one which has had significant population depletion and/or habitat destruction and is potentially endangered but (is) presently reproducing at or near normal where it still occurs. The amphibian report has similar endangered and threatened definitions, but also lists species as undetermined and stable. Undetermined status has been assigned to those species for which there is insufficient data available to draw any conclusions with regard to current distribution and abundance in the San Diego county. Stable status was given to a species (or subspecies) whose San Diego county population levels appear to be holding their own. No sensitive reptiles or amphibians were observed during the surveys although the San Diego coast horned lizard and the orange-throated whiptail would be expected to occur within the sage scrub on-site, primarily the habitat near the southern boundary. Both of these species are listed by the State as Species of Special Concern and as Category 2 Federal Candidate Species. The Biological Survey and Report for Emerald Ridge - East . 13 I I I I I I I I I I I I I I I I I I I SDKS considers the San Diego homed lizard endangered and the orange-throated whiptail threatened. Both species are threatened by habitat destruction and the San Diego horned lizard is also threatened by commercial exploitation. D. Sensitive Habitats Sage Scrub. Sage scrub is a community that supports a wide range of native California plants and wildlife, many of which are considered sensitive by various agencies and/or interest groups. Sage scrub in southern California has been severely degraded by past urbanization. Conversion to agriculture has severed connections among remnant habitat patches resulting in their increased isolation. Connections among habitat patches are critical to the long-term survival of sage scrub inhabiting species (CDFG and California Resources Agency 1993). Wetland Vegetation. Riparian habitats, including wetland vegetation, occur adjacent to streams and riverbeds where soil moisture is close to the surface. These habitats are considered sensitive in San Diego County for their wildlife value and limited distribution in the region. In recent years, their limited distribution has been further reduced by flood control projects, agriculture and urban development. Wetland habitats are protected by CDFG and often these habitats fall under the jurisdiction of the U.S. Army Corps of Engineers (ACOE) pursuant to Section 404 of the Clean Water Act, especially when major drainages are involved. E. Habitat Evaluation &The study site supports two native plant community, sage scrub and wetland habitat. Due to the ^relatively undisturbed state of the sage scrub on-site, the continuation of the habitat off-site to the west, the presence of a Federally Threatened species (gnatcatcher), and the potential presence of two sensitive reptile species (San Diego coast horned lizard and orange-throated whiptail), the quality of the sage scrub adjacent to the southern boundary of the site would be regarded as high. The habitat value for the two narrow strips of sage scrub near the eastern boundary would be considered low because of the small size of the strips (a total of 0.50 acre, the isolation of the two strips and their more disturbed nature. Disturbance from the adjacent disced areas, occurrence of the on-site habitat in a narrow strip, and the absence of typical riparian habitat wildlife diminishes the overall value of the on-site wetland vegetation. Aside from use as raptor foraging habitat, the disturbed area is of little value to wildlife due to its disturbed nature. This is in part because the level of wildlife use corresponds with the vegetation complexity and biomass, both of which are relatively low in this area. Non-native species are also used to a lesser extent by native wildlife species. Biological Survey and Report for Emerald Ridge - East 14 I I I I I I I I I I I I I I I I I I I V. IMPACT ANALYSIS A. Assumptions and Assessment Guidelines Impacts to the flora and fauna observed or expected at the site were determined to be significant or insignificant based upon the sensitivity of the resource and the extent of the impact. Resources are generally considered significant if they are limited in distribution and then- ecological role is critical within a regional and local context. Habitats supporting species listed as rare, endangered, or threatened by the agencies that enforce the California or Federal Endangered Species Act are also regarded as significant resources. In addition, habitats meeting the following criteria were also determined to be significant: • Natural areas, communities, and habitats of plant and animal species that are restricted in distribution. • Habitat that is critical to species or a group of species for feeding, breeding, resting, and migrating. • Biological resources that are of scientific or educational interest because they exhibit unusual physiological, social, or ecological characteristics. • Buffer zones to protect significant resources. • Corridors or areas that link significant wildlife habitats. A significant impact to a sensitive resource may be direct, indirect, or cumulative. An impact is regarded as direct when the primary effects of the project result hi loss of habitat that would cause a reduction hi the density or diversity of biological resources within the region. The magnitude of an indirect impact is the same as a direct impact, however, the impact occurs from a secondary effect of the project. An impact is regarded as cumulative when the project impact is not significant but the combined incremental impact of it and other projects hi the region is significant. The extent of the impact on the sensitive resource must also be considered hi determining the significance of an impact. For certain highly sensitive resources (e.g., an endangered species) any impact would be perceived as significant. Conversely, other resources which have a low sensitivity (e.g., species with a large, locally stable population but may be declining elsewhere) could sustain a relatively large area of impact or population loss and not result hi a significant impact. Biological impacts are considered insignificant if the resource in question does not meet the above criteria for sensitivity or the extent of impact is not considered significant. Biological Survey and Report for Emerald Ridge - East 15 I I I I I I I I I I I I I I I I I I I B. Project Impacts A summary of the impacts for the TM is presented in Table 3 and shown on Figures 4a and 4b (see Map Pocket). This impact analysis assumes that any land not preserved within open space will be impacted. Implementation of the Emerald Ridge - East project would impact 0.59 acre of sage scrub (including 0.15 acre of disturbed sage scrub) and 19.17 acres of disturbed land for a total of 19.76 acres. Table 3. Emerald Ridge - East Impacts(1) Habitats Existing Impacts Open Space Sage Scrub Wetland Vegetation Drainage Channel Disturbed Total 1.47® 0.17 0.03 25.73 27.40 0.59(2) 0.00 0.00 19.17 19.76 0.88 0.17 0.03 6.56 7.64 (1) Measured in acres. (2) Includes 0.15 acre of disturbed sage scrub. The loss of disturbed land would not be considered a significant loss. Of the 0.59 acre of sage scrub that would be impacted, 0.50 acre would occur in two small, narrowly vegetated strips along the eastern border of the property. An additional 0.09 acre of sage scrub in the southern portion of the site would be impacted. The loss of any sage scrub would be considered significant. Sensitive Plants. The potential loss of ashy spike-moss and western dichondra associated with the loss of sage scrub would not be considered significant since approximately 66% of the sage scrub will be preserved in open space. Sensitive Animals. Any loss of the disturbed land would reduce the foraging habitat for the turkey vulture and the northern harrier, however, this loss would not be considered significant. With the loss of sage scrub would be a potential loss of habitat for the San Diego coast horned lizard and the orange-throated whiptail. This would not be considered a significant loss since approximately 66% of the sage scrub on-site will be preserved in open space. Indirect impacts (e.g., construction noise) to the California gnatcatcher may occur during construction adjacent to the sage scrub near the southern boundary, however, any indirect impacts that may occur will be minimized by the mitigation measures described below. Biological Survey and Report for Emerald Ridge - East 16 LEGEND IIIIIIIIIHIlDiegan Coastal Sage Scrub Disturbed Sage Scrub ] Disturbed RiparianVegetation (RV) Drainage Channel California Gnatcatcher Project Boundary Brian F. Mooney Associates 200' 400' Biological Impacts Map Figure 4a Emerald Ridge - East I I I I I I I I I I I I I I I I I I I VI. MITIGATION MEASURES A total of 7.64 acres of habitat would be placed in Open Space Lots 61, 62, and 63 (Table 3, Figures 4a and 4b). Open Space Lot 61 would preserve 0. 17 acre of wetland vegetation within the Encinas Creek channel and 4.81 acre of disturbed land. Open Space Lot 62 would preserve 0.88 acre of sage scrub and create a corridor to connect with habitat off-site to the south. This open space lot would also preserve 0.03 acre of the drainage channel and 0.92 acre of disturbed land. Open Space Lot 63 would include 0.83 acre of disturbed land that would be graded to a 2:1 slope and landscaped. The proposed open space should be dedicated to the City of Carlsbad for preservation in perpetuity. Grading, placement of structures, removal or addition of vegetation shall be prohibited within the open space easement. Vegetation may be selectively removed upon written order of the appropriate fire control authority for the purpose of reducing an identified fire hazard. Exceptions for future utility easements may also be approved within the open space easement, pursuant to City Council policies for such exceptions. Any unauthorized encroachments into dedicated open space shall require mitigation in the form of in-kind habitat restoration on-site. A. Mitigation Program The Emerald Ridge - East project will be responsible for placing 7.64 acres of existing land into the proposed open space lots to include 0.88 acre of sage scrub, 0. 17 acre of wetland vegetation, 0.03 acre of drainage channel and 6.56 acres of disturbed land (Table 3, Figures 4a and 4b).' A total of 0.68 acre would compensate for 0.59 acre of sage scrub impacted with implementation of the project. Impacts to 0.50 acre of sage scrub that occurs in two strips along the eastern property boundary will be mitigated at a 1:1 ratio (0.50 acre). A minimum ratio is recommended due to the relatively small size of the habitat occurring hi two narrow strips (0.20 acre and 0.30 acre), the isolation of the strips from contiguous habitat, and the absence of any State or Federal listed species. Impacts to an additional 0.09 acre of sage scrub hi the southern portion of the property will be mitigated at a 2:1 ratio (0.18 acre). The habitat hi this area is of higher quality than that of the two strips near the eastern boundary, is contiguous with sage scrub off-site to the south, and a Federally listed species (gnatcatcher) has been detected in the area. The impact, however, occurs in a narrow linear strip adjacent to the fallow field. Impacts to 0.59 acre of sage scrub will be mitigated by the purchase of 0.68 acre of habitat that is within a mitigation bank preserve, such as Carlsbad Highlands hi the City of Carlsbad (City) or by creation of sage scrub within the 0.92 acre of disturbed habitat in the southeastern corner of the property. Mitigating for sage scrub impacts by purchase in a mitigation bank will ensure preservation of land within a large preserve area that meets the USF&WS Natural Community Conservation Planning (NCCP) requirements. Compliance with the City Habitat Management Plan for impacts to sage scrub will require coordination with staff from the City and may include the preparation of a Habitat Loss Permit Biological Survey and Report for Emerald Ridge - East TS I I I I I I I I I I I I I I I I I I I as a result of the loss of sage scrub. In addition, finalization of the mitigation plan may require concurrence with staff from both the CDFG and the USF&WS NCCP programs. Clearing and grubbing of sage scrub that will be impacted shall occur during the non-breeding season (August 1 to February 28) for the gnatcatcher. In addition, possible construction noise impacts to breeding gnatcatchers and other potential bird species should be avoided by prohibiting heavy construction adjacent to sage scrub during the breeding season (March 1 to July 31). Construction activities (including vegetation clearing and grubbing) adjacent to sage scrub shall be monitored by a biologist to avoid any intrusion into this habitat. These measures shall include: marking the limits of construction conspicuously; a discussion by the biologist with the construction superintendent regarding the sensitivity of these areas and the need to prevent any impacts from occurring; site visits by the biologist to monitor compliance; and a monthly report to be submitted to the developer and interested resource agencies. VII. REFERENCES Bailey, L.H. 1924 Manual of Cultivated Plants. MacMillan Publishing Co. New York. Beauchamp, R. Mitchel 1986 A Flora of San Diego County, California. Sweetwater River Press, National City, California. 241 pp. Binford, Laurence C. 1986 Checklist of California Birds - 1986. Western Birds 17:1-16. Bowman, Roy H. 1973 Soil Survey of the San Diego Area, California. U.S.D.A. California Burrowing Owl Consortium 1993 Burrowing Owl Survey Protocol and Mitigation Guidelines. April. California Department of Fish and Game 1994 Special Animals. California Department of Fish and Game. 1995a Sensitive Plants List. California Department of Fish and Game. 1995b Database RareFind Report. California Department of Fish and Game. California Department of Fish and Game and California Resources Agency 1993 Southern California Coastal Sage Scrub Natural Community Conservation Planning Process Guidelines. November. biological Survey and Report for Emerald Ridge - East 19 I _^_ I DeBenedictis, Paul A. • 1989 Comments on the Thirty-seventh Supplement to the Checklist of North American Birds. American Birds 43(3):416-418. Dudek and Associates, Inc. 1995 Wetland Delineation Study for the Hidden Valley Road Alignment for Sambi I Seaside Heights, Kelly Property and Mar Vista. Prepared for Toyohara America, Inc. January. I Everett, William T. 1979 Threatened, Declining, and Sensitive Bird Species in San Diego County. Sketches m 29(10):2-3. Hickman, James C., ed. 1 1993 The Jepson Manual: Higher Plants of California. University of California Press. Berkeley, California. 1400 pp. • Holland, R.F. 1986 Preliminary Descriptions of the Terrestrial Natural Communities of California. Nongame-Heritage Program, California Department of Fish and Game. • Jameson, E.W., Jr. and H.J. Peeters 1988 California Mammals. University of California Press, J^os Angeles, California. ™ Jennings, Mark R. 1983 Annotated Check List of the Amphibians and Reptiles of California. California • Fish and Game 69(3):151-171. Jones, J.K., D.C. Carter, H.H. Genoways, R.S. Hoffman, and D.W. Rice I 1982 Revised Checklist of North American Mammals North of Mexico. Occasional Papers of the Museum Texas Tech University 80:1-22. • Mooney, Brian F. Associates 1991 Biological Survey and Report for the Carlsbad Zone 20 SPA. Prepared for the I City of Carlsbad. August. 1994 Biological Survey and Report for Hidden Valley Estates. Prepared for Kelly Trust UDY 8-31-81. September. 1 1995 Biological Survey and Report for Emerald Ridge - West, CT 95-03/SDP 95- 06/HDP 95-06. Prepared for MS{ California LLC. August. I Munz, Philip A. 1974 A Flora of Southern California. University of California Press, Berkeley, Los Angeles. 1086 pp. I I Biological Survey and Report for Emerald Ridge - East 20 I I • RECON • 1991 Biological Constraints Analysis for Kelly Trust Property in Carlsbad, California. Prepared for the Kelly Trust. November. San Diego Herpetological Society — 1980 Survey and Status of Endangered and Threatened Species of Reptiles Natively I Occurring in San Diego County. San Diego Department of Agriculture. 1980a Status of the Indigenous Amphibians of San Diego County. San Diego County • Department of Agriculture. Skinner, Mark W. and Bruce M. Pavlik 1 1994 Inventory of Rare and Endangered Vascular Plants of California. Special Publication No. 1, Fifth Edition. February. I Tate, James, Jr. 1986 The Blue List for 1986. American Birds 40(2):227-236. Philip 1984 The Birds of San Diego County. San Diego Society of Natural History. • Unitt, Philip I I I I I I I I I I I Biological Survey and Report for Emerald Ridge - East 21