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HomeMy WebLinkAbout3190; Rancho Sante Fe Road Alignment; Rancho Sante Fe Road Alignment; 2001-09-14p fe p fe p fe p to DUDEK & ASSOCIATES, INC. Professional Teams for Complex Projecis September 14, 2001 Engineenng, Planning, Environmental Sciences and Management Senrices Corporate Office: 605 Third Street Encinitas, California 92024 760.942.5147 Fax 760.632.0164 1576-18 U.S. Fish and Wildlife Service Attn: Christine Moen 2730 Loker Avenue West Carlsbad, CA 92008 Subject: California Gnatcatcher Survey for the Rancho Santa Fe Road Realignment Project^ City of Carlsbad, San Diego County, California; Permit Number TE- 840619-1 P P PI fe Dear Ms. Moen: This report documents the coastal Califomia gnatcatcher {Polioptila califomica califomica) protocol survey conducted for the approximately 138-acre Rancho Santa Fe Road Realignment project site. The areas surveyed include all suitable habitat within the project's area of potential effect (APE) {e.g., coastal sage scmb and subassociations; a total of approximately 63 acres) and an approximately 40-acre buffer adjacent to the project's APE where habitat suitable for gnatcatchers is contiguous with suitable habitat within the project's APE. The Califomia gnatcatcher is a federally-listed threatened species and a Califomia Department of Fish and Game species of special concem. It is closely associated with coastal sage scmb (CSS) habitat, particularly that dominated by Califomia sagebrush {Artemisia californica) and Califomia buckwheat {Eriogonum fasciculatum). It typically occurs below 950 feet elevation and on slopes less than 40%. The species is threatened primarily by loss, degradation, and fragmentation of coastal sage scrub habitat and is also impacted by brown-headed cowbird {Molothrus ater) parasitism. Project Description, Location and Existing Conditions The City ofCarlsbad proposes to widen and realign Ranch Santa Fe Road from two lanes to an ultimate six lane prime arterial roadway from approximately 100 feet south of La Costa Avenue/Rancho Santa Fe Road intersection to approximately 100 feet north of the Melrose Drive/Rancho Santa Fe Road intersection {Figures 1&2). The project site is located near the southeastem portion of the City of Carlsbad and is surrounded by commercial and residential land use as well as undeveloped land. It lies within the U.S. Geological Survey 7.5 minute topographic map, Rancho Santa Fe quadrangle, Wl/2 of Section 29, SEl/4 of Section 30, El/2 Section 31, Range 3 West, Township 12 South. Elevation of the project APE ranges from approximately 300 feet above mean sea level in the south to approximately 400 feet above mean sea level in the north. The terrain in area ranges from relatively flat ground to sloping hillsides. Soils in the project vicinity consist of five separate soil types underlain by Mesozoic granitic rocks (Bowman 1973). The predominant soil type at the site is the Huerhuero loam on 5 to 9 percent slopes. The Huerhuero series consists of moderately well drained loams that have a clay subsoil. These soils developed in sandy 1 PK P 2 c fe p fe pi • Orange County San Diego / Imperial Beach Mexico 1"-8 Miles Tijuana Rancho Santa Fe Rd. Realignment Si Bridge Replacement • Focused Calif. Gnatcatcher Survey Regional Map FIGURE BASE MAP SOURCE: USGS 7.5 Minute Series, Rancho Santa Fe Quadrangle 1" =2000' Rancho Santa Fe Rd. Realignment St Bridge Replacement - Focused Calif. Gnatcatcher Survey Vicinity Map FIGURE ff m fe P p P fe p P r k P P c p fe p 1^ marine sediments. The erosion hazard and runoff of this clayey loam is moderate, the permeability is slow to moderate, and the available water holding capacity is four to five inches. The soil has a rooting depth of 20 to 40 inches. Other minor soil types in the project vicinity are Cieneba coarse sandy loam, San Miguel rocky silt loam, and two types of VisaHa sandy loam. Vegetation Communities Based on species composition and general physiognomy, eleven plant communities or habitat types have been identified within the project APE: coastal sage scrub (bumed and disturbed forms), coyote brush scrub (disturbed), southem mixed chaparral (natural and bumed forms), valley needlegrass grassland, freshwater marsh, southem willow scrub, disturbed wetland, eucalyptus woodland, annual non-native grassland, disturbed habitat, and developed land. The habitat types for the project site are described below, their acreages are presented in Table 1, and their spatial distributions are available in the map pocket at the end of the report. TABLE 1. VEGETATION COMMIMTIES FOR THE RANCHO SANTA FE ROAD REALIGNMENT PROJECT Vegetation Community Total Project Acres Coastal Sage Scrub (burned) 35.1 Coastal Sage Scrub (disturbed) 23.5 Coyote Brush Scrub (disturbed) 1.9 Soutiiern Mixed Chaparral 1.4 Southem Mixed Chaparral (bumed) 14.4 Valley Needlegrass Grassland 0.1 Valley Needlegrass Grassland/Coastal Sage Scrub 2.2 Freshwater Marsh 0.4 Southern Willow Scrub 1.72 Disturbed Wetland 0.27 Annua! Non-native Grassland 17.2 Eucalyptus Woodland 2.7 Disturbed Habitat 12.3 Developed 25.2 TOTAL 138.3 Diegan Coastal Sage Scrub Diegan coastal sage scrub is a coastal plant community composed of a variety of low, soft, aromatic subshrubs, characteristically dominated by drought-deciduous species such as coastal, Califomia buckwheat, and sages {Salvia spp.), with scattered evergreen shmbs, including lemonadeberry {Rhus integrifolia), laurel sumac {Malosma laurina), toyon {Heteromeles arbutifolia), and a diverse understory of annual herbs and forbs and perennial grasses. P In the APE, Diegan coastal sage scmb was present on the west-facing hillsides along the eastem side of B Rancho Santa Fe Road prior to fhe October 1996 fire. Previous surveys found that areas supporting coastal sage scmb prior to the fire are recovering, with new growth {i.e., primarily seedlings) of coastal sagebmsh, white sage {Salvia apiana), black sage {Salvia mellifera), deerweed {Lotus scoparius), bush monkeyflower E {Mimulus aurantiacus), coastal goldenbush {Isocoma menziesii ssp. veneta) and laurel sumac. The understory species were particularly abundant and included blue dicks {Dichelostemma capitata), early onion {Allium praecox), lupines {Lupinus spp.), fascicled tarweed {Hemizonia fasciculata), cryptantha {Cryptantha P spp.), mallow {Malacothamnus fasciculatus sp.), and chia {Salvia columbariae). Nearly the entire APE fe appears to have been affected by the 1996 fire; however, in general it appears that native plant diversity is greater in the northem portion ofthe APE, where as the southem portion contains a higher percent cover of p non-native grasses and forbs. Areas where native species account for between 20% to 70% ofthe total |g ground cover (by visual estimation) were designated as disturbed coastal sage scmb (23.5 acres). Areas with greater than 70% native species coverage were designated as bumed coastal sage scmb (35.1 acres). P P m Coyote Brush Scrub Coyote bmsh scmb is not recognized as a native plant community by Holland (1986). Nonetheless, it is a distinct vegetational association in southem Califomia, dominated by coyote bmsh {Baccharispilularis ssp. consanguinea), usually with a few scattered individuals of other native shmb species and many non-native species. It frequently is a successional community that occurs in more mesic sites and along drainages where coastal sage scrub or chaparral has been eliminated by perturbation. Within the APE this habitat is characterized by nearly uniform stands of coyote bmsh with a few other native shmbs in low density, including Califomia sagebmsh, flat-top buckwheat, Mexican elderberry {Sambucus mexicanus), and a variety of non-native herbs and grasses. It was found adjacent to the existing paved road sections where it crosses the creek, and appears to be the result of disturbed soils in this area. A total of 1.9 acres was mapped by DUDEK biologists as a part of the 1997 resource mapping. Coyote brush scrub typically is considered a subcategory of coastal sage scmb by the resource agencies because as a shmb type it does not conform well to a chaparral type. Its general plant architecture and ii density also apparently are similar enough to "tme" coastal sage scmb to support the "target" coastal sage scrub animal species Califomia gnatcatcher. fe Southern Mixed Chaparral P Southem mixed chaparral is a drought- and fire-adapted community of broad-leaved sclerophyllous shmbs, li 1.5-3.0 m tall, forming dense impenetrable stands. It develops primarily on mesic north-facing slopes and canyons. This association is tjqiically a mixture of chamise {Adenostoma fasciculatum), mission manzanita E {Xylococcus bicolor), ceanothus {Ceanothus spp.), and laurel sumac. Other sub-dominant shmbs include redberry {Rhamnus crocea), yellow-bush penstemon {Keckiella antirrhinoides), Califomia buckwheat, scmb oak {Quercus berberidifolia), and Mojave yucca {Yucca schidigera). The understory is fairly depauperate p owing to the dense canopy and perhaps, the allelopathic properties of certain shmb species. In the APE, southem mixed chaparral was present prior to the October 1996 fire on east-facing hillsides p along the westem side of Rancho Santa Fe Road and south of San Marcos Creek. One small patch was not Il bumed and another appears fully recovered during winter 2000 surveys. Other patches of this vegetation p fe fe community in the APE are undergoing recovery and include new growth of chamise, black sage, white sage, deerweed, bush monkeyflower, laurel sumac, and redberry. Understory species common in the bumed areas E included fascicled tarweed, chia, bush mallow, soft chess {Bromus hordeaceus), slender wild oat {Avena barbata), and ripgut grass {Bromus diandrus). A total of 15.8 acres of chaparral was mapped in the entire APE; the majority of chaparral (14.4 acres) mapped was designated as bumed southem mixed chaparral. 2 Valley Needlegrass Grassland IP Valley needlegrass grassland is a native grassland dominated by perennial bunchgrasses, such as needlegrass ^ {Nassella spp.). This plant community typically alternates with coastal sage scmb on some clay soils, often on more mesic exposures and at the bases ofslopes, but also may occur in large patches. P H p P Within the APE, valley needlegrass grassland is dominated by purple needlegrass {Nassella pulchra); a number of other native forbs occur there also. Two very small remnant patches were found among coyote bmsh scmb north of the creek and in a canyon bottom in the eastem portion of the APE. Two larger, bumed areas were mapped as valley needlegrass grassland/ coastal sage scmb in the Questhaven Road section of the APE. These areas contain scattered coastal sage scmb shmb species but the dominant cover consists of grassland species. A total of 2.3 acres of valley needlegrass grassland was mapped; 2.2 acres ofthis total was mapped as valley needlegrass grassland/coastal sage scmb. Freshwater Marsh ^ Freshwater marsh occurs in drainages, seepages, and other perennially moist low places. This community is characterized by perennial, emergent monocots {e.g., grasses and lilies), 2-3 m (6-10 feet) tall, such as E cattails and bulmshes. Understory species typically include curly dock {Rumex crispus), marsh fleabane {Pluchea odorata), and a variety of hydrophytic grasses and herbs. tm Three areas in the APE were mapped as freshwater marsh; two areas north of the San Marcos Creek and west of Rancho Santa Fe Road and an area along the eastem edge of Rancho Santa Fe Readjust south of La Costa Meadows Drive. Two of the small marsh areas occur in a disturbed grassland and support cattail, English P ryegrass {Lolium multiflorum), bristly ox-tongue {Picris echioides), curly dock, and msh. The small marsh fe area east of Rancho Santa Fe Road is a drainage ditch between paved areas. A total of 0.43 acre was mapped by DUDEK biologists as a part ofthe 1997 resource mapping. P ii Southern Willow Scrub p Holland (1986) describes southera willow scmb as a dense, broad-leaved, winter-deciduous riparian thicket fe dominated by several willow species {Salix spp.), with scattered emergent Fremont cottonwood {Populus fremontii) and westem sycamores {Platanus racemosa). Willow density typically inhibits the development m of an understory. fe The southem willow scmb in San Marcos Creek was not bumed in 1996 and supports arroyo willow scmb p {Salix lasiolepis), westem sycamore, Fremont's cottonwood, msh {Juncus spp.), winged three-square Ig {Scirpus americanus), Mexican elderberry, and cattails {Typha sp.). Understory species in the southem willow scmb include Califomia mugwort {Artemisia douglasiana), curly dock, yerba mansa {Anemopsis S californica), rigid hedge-nettle {Stachys ajugoides var. rigida), Mexican tea {Chenopodium ambrosioides), and poison-oak {Toxicodendron diversilobum). A total of 1.72 acres of southem willow scmb was mapped. . 7 HI Disturbed Wetland B in general the disturbed wetlands designation is used in areas where hydrophytic vegetation, significant hydrology and hydric soils are present and the plant community appears to be disturbed. Disturbed wetlands are usually dominated by herbaceous species such as English ryegrass, mshes, curly dock and aimual rabbit's P foot grass (Polypogon monspeliensis). E P fe I* P p fe C Within the APE, disturbed wetlands occur in a shallow drainage surrounded by bumed and disturbed coastal sage scmb with some grasslands; the wetland occupies 0.27 acre. Dominant species within the wetland include English ryegrass and msh. Curly dock also occurs here. It should be noted that this area was mapped as freshwater marsh in a HELIX report; HELIX reported a similar species composition which did not include typical freshwater marsh species. Therefore, the disturbed wetland designation distinguishes this il area from areas mapped as freshwater marsh elsewhere in the APE. Annual (Non-native) Grassland Where the native vegetation has been disturbed repeatedly or often by grazing, agriculture, fire, or mechanical dismption, the land reverts to annual (non-native) grassland/mderal (weedy) habitat. In these situations non-native grasses and weeds dominate the habitat, and there are a few early successional elements ofthe former community. Characteristic species include slender wild oat, soft chess, foxtail fescue {Vulpia megalura), ripgut grass, foxtail chess {Bromus madritensis ssp. rubens), filaree {Erodium spp.), sweet feimel {Foeniculum vulgare), and black mustard {Brassica nigra). In the APE, annual grassland/mderal habitat predominates north of San Marcos Creek in old agricultural fields and also exists adjacent to the existing bridge on the east side. This area did not bum in the wildfire. Annual grassland occurs in the southem portion of the APE where non-native species have dominated in post-bum coastal sage scmb habitat. A total of 17.2 acres of annual grassland and mderal habitats was mapped. Eucalyptus Woodland Eucalyptus woodland consists of monotypic stands of eucalyptus {Eucalyptus spp.). The understory typically is depauperate and often supports annual grasses such as ripgut grass. Eucalyptus woodland occurs in numerous locations both east and west of Rancho Santa Fe Road. Many of the eucalyptus trees south of San Marcos Creek were damaged and some were killed by the wild fire. A total of 2.7 acres were mapped within the APE. Disturbed Habitat Disturbed habitat includes dirt roads and graded areas that either support a limited amount of weedy, non- native species or are characterized by the absence of vegetation. Disturbed habitat typically shows evidence of recent or periodic mechanical clearing. Disturbed habitat in the APE includes dirt roads dominated by sweet fermel, black mustard, and telegraph weed {Heterotheca grandiflora). A total of 12.3 acres was mapped. 8 Developed Developed areas include paved roads and sites with physical stmctures, including buildings and parking lots. In the APE, developed areas include the industrial park east of Rancho Santa Fe Road, residential development along Melrose Drive and paved roadways. A total of 25.2 acres was mapped. Methods The focused survey for the Califomia gnatcatcher was conducted on August 13,20 and 27,2001 by DUDEK biologist Jeff Priest (permit #TE-840619-1 ). The survey was conducted following the currently accepted protocol of the U.S. Fish and Wildlife Service, Coastal California Gnatcatcher (Polioptila californica californica) Presence/Absence Survey Protocol. The survey included the typical three visit survey to the site at weekly intervals. The route used to survey the habitat was arranged to ensure complete coverage of the suitable habitat within the APE and provide for a buffer of approximately 40 acres where contiguous suitable habitat occurred adjacent to the APE {i.e., approximately 100 acres of suitable habitat surveyed per visit) {Figure 3). A 1"=750' topographic map of the APE was available to map any gnatcatchers detected. Binoculars (7X50) were used to aid in detecting and identifying bird species. The weather conditions were generally pleasant and mild as shown in the table below. Taped gnatcatcher vocalizations were used frequently in order to elicit a response from the species, if present. The tape was played approximately every 50 to 100 feet and when a gnatcatcher was detected, the playing of the tape ceased in order to avoid harassment. TABLE 2. SURVEY DATA - RANCHO SANTA FE ROAD REALIGNMENT PROJECT im mm Dale Temp. (F) Wind (mph) Cloud Cover Time Tolal Suitable Acres/ (Ac/Hr) 13 Aug 01 67-82 0-2 Clear 0600-1130 100/18 mm 20 Aug 01 66-85 0-2 30% to Clear 0600-1150 100/16 •m 27 Aug 01 64-78 0-2 Overcast/Fog to Clear 0620-1210 100/18 Results Twelve California gnatcatchers were detected within the project APE during the focused survey {Figure 4). Five groupings of gnatcatchers were detected and were comprised of two individual pairs, a pair and one fledge, three fledges and two fledges. A total of thirty-three species of wildlife were detected during the surveys. A list of species detected is included as Appendix A. mm Rancho Santa Fe Road Realignment 8i Bridge Replacement • Focused California Gnatcatcher Survey Survey Route FIGURE r 2 Rancho Santa Fe Road Realignment 8i Bridge Replacement - Focused California Gnatcatcher Survey Gnatcatcher Locations on Site Plan Map FIGURE p ii Please feel free to contact me at (760) 942-5147 with questions or if you require additional information. Very tmly yours, DUDEK & ASSOCLS.TES, INC. J^ffr^ '^ildlffe^Biologist' P^it Number TE-840619-1 cc: Carrie Loya-Smalley City of Carlsbad Literature Cited r k r k Bowman, RH. 1973. Soil Survey, San Diego Area, Califomia, Part 1. United States Department ofthe Agriculture. 104 pp. + appendices. Holland, R. F. 1986. Preliminary descriptions of the terrestrial natural communities ofCalifornia. Nongame-Heritage Program, Califomia Department of Fish and Game. 156 pp. P P k p 12 1 L p Ili m P m P fe APPENDIX A WILDLIFE SPECIES -VERTEBRATES REPTILES IGUANIDAE - IGUANID LIZARDS Sceloporus occidentalis - western fence lizard Vta stansburiana - side-blotched lizard VIPERIDAE - VIPERS Crotalus viridis - western rattlesnake BIRDS ACCIPITRIDAE - HAWKS Buteo jamaicensis - red-tailed hawk Buteo lineatus - red-shouldered hawk fe FALCONIDAE - FALCONS Falco sparverius - American kestrel im PHASIANIDAE - PHEASANTS & QUAILS Callipepla californica - California quail E COLUMBIDAE - PIGEONS & DOVES Zenaida macroura - mourning dove G TYTONIDAE - BARN OWLS Tyto alba - bara owl S TROCHILIDAE - HUMMINGBIRDS Calypte anna - Anna's hummingbird g Calypte costae - Costa's hummingbird TYRANNIDAE - TYRANT FLYCATCHERS •I Sayornis nigricans - black phoebe CORVIDAE - JAYS & CROWS Aphelocoma coerulescens - scmb jay Corvus brachyrhynchos - American crow Corvus corax - common raven 13 r fe p p 'k m fe AEGITHALIDAE - BUSHTITS Psaltriparus minimus - bushtit TROGLODYTIDAE - WRENS Thryomanes bewickii - Bewick's wren MUSCICAPIDAE - KINGLETS, GNATCATCHERS, THRUSHES & BABBLERS Chamaea fasciata - wrentit Polioptila califomica - California gnatcatcher MIMIDAE - THRASHERS Toxostoma redivivum - California thrasher EMBERIZIDAE - WOOD WARBLERS, TANAGERS, BUNTINGS & BLACKBIRDS Melospiza melodia - song sparrow Pipilo crissalis - California towhee Pipilo maculatus - spotted towhee FRINGILLIDAE - FINCHES Carpodacus mexicanus - house finch Carduelis psaltria - lesser goldfinch MAMMALS LEPORIDAE - HARES & RABBITS Sylvilagus bachmani - brush rabbit SCIURIDAE - SQUIRRELS Spermophilus beecheyi - California ground squirrel GEOMYIDAE - POCKET GOPHERS Thomomys bottae - Botta's pocket gopher CANIDAE - WOLVES & FOXES Canis latrans - coyote P 14 fe P P