Re: Coastal California Gnatcatcher Focused Survey Results for the Sunrise Gardens Property, City of San Marcos, San Diego County, California

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1 April 2 nd, 2006 Mr. John Westermeier Kleinfelder, Inc Valley Vista Drive, Suite 150 Diamond Bar, CA Re: Coastal California Gnatcatcher Focused Survey Results for the Sunrise Gardens Property, City of San Marcos, San Diego County, California Dear Mr. Westermeier: The following letter report summarizes the results of a focused survey program conducted to determine the presence/absence of the federally threatened coastal California gnatcatcher (Polioptila californica californica) (CAGN) within the Sunrise Gardens project site. On March 30, 1993, the CAGN was listed as threatened by the United States Fish and Wildlife Service (USFWS) (USFWS 1993) and designated as a Species of Special Concern by the California Department of Fish and Game (CDFG). The USFWS describes the natural history of the CAGN as follows: The insectivorous coastal California gnatcatcher is a small (length 11 centimeters (4.5 inches), weight 6 grams (0.2 ounces)), long-tailed member of the old world warbler and gnatcatcher family Sylviidae (American Ornithologist Union 1998). The bird s plumage is dark blue-gray above and grayish-white below. The male has a distinctive black cap which is absent during the winter. Both sexes have a distinctive white eye-ring. (USFWS 2000) This subspecies is restricted to coastal southern California and northwestern Baja California, Mexico, from Ventura and San Bernardino Counties, California, south to approximately El Rosario, Mexico, at about 30 degrees north latitude (American Ornithologist Union 1957, Atwood 1991, Banks and Garner 1992, Garrett and Dunn 1981). An elevation of the historic range of the coastal California gnatcatcher indicates that about 41 percent of its latitudinal distribution is within the United States and 59 percent within Baja California, Mexico (Atwood 1990). (USFWS 2000) PROJECT SITE LOCATION/DESCRIPTION The approximately 14-acre project site is located in the City of San Marcos in San Diego County, California as shown in Figure 1, Regional Map, and Figure 2, Aerial Vicinity/Vegetation Communities Map. The project site extends south from Barham Drive along a narrow strip of land while the main portion of the property is bordered on the west by Grande Vista and to the north by Alta Vista. The property is located on the United States Geological Survey (USGS) 7.5' San Marcos Quadrangle, Township 12 South, Range 2 West, central portion of Section 18. The project site supports several plant communities including non-native grassland, avocado orchards (abandoned), mixed sage scrub, non-native grassland/mixed sage scrub, and an abandoned barn as shown in Figure 2, Aerial Vicinity/Vegetation Communities Map. The property is almost completely bordered by development including a trailer park and industrial buildings. As 701 Palomar Airport Road, Suite 300, Carlsbad, California Tel (949) Fax (760) , info@cadreenvironmental.com

2 Mr. John Westermeier April 2 nd, 2006 Page 2 noted below, all mixed sage scrub and non-native grassland/mixed sage scrub habitats were surveyed to determine the presence/absence of the coastal California gnatcatcher. These habitat types were dominated by black sage (Salvia mellifera), orange-bush monkey-flower (Mimulus aurantiacus), coyote brush (Baccharis pilularis) and less common species included chamise (Adenostoma fasciculatum), laurel sumac (Malosma laurina), California sagebrush (Artemisia californica), and manzanita (Arctostaphylos sp). METHODOLOGY Focused surveys were conducted to determine the presence or absence of the federally-threatened coastal California gnatcatcher in all areas onsite containing suitable habitat. Surveys were conducted by Ruben Ramirez (permit number TE ). Methods employed were in accordance with USFWS Coastal California Gnatcatcher Presence/Absence Survey Guidelines, revised July 28, Accordingly, nine (9) non-breeding season surveys were performed no less than 2 weeks apart, between the hours of 6:00 A.M. and 12:00 P.M., within all portions of the project site containing potentially suitable habitat. Approximately 14 acres of suitable habitat (mixed sage scrub and non-native grassland/mixed sage scrub) occurs within the project site boundaries. The permitted investigator visited each habitat patch and slowly walked through it, stopping at approximately 200-foot intervals, uttering pishing sounds, and playing a tape of recorded California gnatcatcher vocalizations. The tape was played for several seconds at each interval, followed by a brief pause to listen for a response. Surveys were conducted on October 28 th, November 11 th, 25 th, December 9 th, 2005, January 6 th, 22 nd, February 3 rd, 17 th and March 9 th Weather conditions during surveys were generally conducive to a high level of bird activity. Weather conditions were suitable for surveys, with skies ranging from clear to 25 percent overcast, with winds below Beaufort scale 2. Surveys were suspended whenever conditions became less than favorable. This included periods of rain, excessive wind, or exceedingly hot or cold temperatures. RESULTS No CAGN were detected or are currently expected to occur within the project site boundaries. The scrub and grassland habitats onsite provide foraging and cover habitat for year-round residents, seasonal residents, and migrating songbirds. The overall condition of the scrub vegetation communities is good with the remaining habitats being heavily disturbed. Representative bird species observed onsite include sharp-shinned hawk (Accipiter striatus), American kestrel (Falco sparverius), rock dove (Columba livia), mourning dove (Zenaida macroura), Anna s hummingbird (Calypte anna), Costa s hummingbird (Calypte costae), black phoebe (Sayornis nigricans), Say s phoebe (Sayornis saya), western kingbird (Tyrannus vociferans), American crow (Corvus brachyrhynchos), bushtit (Psaltriparus minimus), Bewick s wren (Thryomanes bewickii), northern mockingbird (Mimus polyglottos), European starling (Sturnus vulgaris), California towhee (Aphelocoma californica), spotted towhee (Pipilo maculatus), song sparrow (Melospiza melodia), and white-crowned sparrow (Zonotrichia leucophrys).

3 Mr. John Westermeier April 2 nd, 2006 Page 3 Please call me if you have any questions or comments. Sincerely, CADRE ENVIRONMENTAL Ruben S. Ramirez, Jr. Research Biologist

4 Mr. John Westermeier April 2 nd, 2006 Page 4 REFERENCES Environmental Management Agency. County of Orange Habitat Classification System, Natural Resources, Geographic Information System (GIS) Project. Santa Ana, California. Hickman, J. C The Jepson Manual: Higher Plants of California. Berkeley: University of California Press. Holland, R.F. 1986, updated Preliminary Descriptions of the Terrestrial Natural Communities of California. Unpublished report. State of California Resources Agency, California Department of Fish and Game, Non-Game Heritage Division, Sacramento, CA. State of California Resources Agency Department of Fish and Game. California's Wildlife: Volume I: Amphibians and Reptiles. Sacramento. State of California Resources Agency Department of Fish and Game. California's Wildlife: Volume II: Birds. Sacramento. State of California Resources Agency Department of Fish and Game. California's Wildlife: Volume III: Mammals. Sacramento. State of California Resources Agency Department of Fish and Game. California Wildlife Habitat Relationships Database System. State of California Resources Agency Department of Fish and Game. RareFind: A Database Application for the Use of the California Department of Fish and Game s Natural Diversity Data Base. Sacramento. U.S. Department of the Interior, Fish and Wildlife Service Endangered and Threatened Wildlife and Plants; Final Designation of Critical Habitat for the Coastal California Gnatcatcher and Determination of Distinct Vertebrate Population Segment for the California Gnatcatcher, Proposed Rule. Federal Register 68(79): U. S. Geological Survey. San Marcos 7.5' Topographic Quadrangle. 1966, photorevised 1988.

5 Figure 1 - Regional Map Sunrise Gardens Coastal California Gnatcatcher Surveys CADRE Environmental not to scale

6 BA RH AM DR IVE MYERS AVENUE PROJECT SITE BOUNDARY Non-native Grasslands Avocado Orchard (Abandoned) Developed Non-native Grassland/ Non-native Grassland/ Source: Eagle Aerial 2003 Figure 2 - Aerial Vicinity/Vegetation Communities Map Sunrise Gardens Coastal California Gnatcatcher Surveys CADRE Environmental 1 inch = 300 feet