Type: report

Article abstract: The purpose of this Biological Diversity Baseline Report for the Lawrence and Barbara Daley Preserve is to provide the County of San Diego with information on existing biological conditions to assist in the development of Area Specific Management Directives. The approximately 597-acre1 Preserve is located in the south central portion of San Diego County, in the community of Dulzura, north and east of Highway 94 and south of Honey Springs Road. Technology Associates International Corporation (Technology Associates) assisted by the San Diego Natural History Museum, conducted baseline biological surveys at the Preserve on behalf of the County of San Diego Department of Parks and Recreation. Baseline surveys were conducted in the winter, spring, and summer of 2009-2010. Biologists conducted the following surveys to assess the current status of biological resources onsite: (1) mapping of vegetation communities, (2) a floral inventory including rare plant surveys, (3) butterfly inventory surveys, (4) pitfall trapping for amphibians, reptiles, and small mammals, (5) arroyo toad surveys, (6) aquatic herpetofauna surveys, (7) diurnal avian point count surveys, (8) nocturnal avian surveys, (9) acoustic bat surveys, (10) small mammal trapping, and (11) track and camera station surveys for medium and large mammals. Due to the 2007 Harris fire that burned all of the Preserve, results of these surveys may under-represent the diversity of plant and wildlife species that occupy the Preserve. Ten vegetation communities were mapped within the Preserve and consist of Diegan coastal sage scrub, coastal sage-chaparral scrub, southern mixed chaparral, native grassland, non-native grassland, southern riparian woodland, coast live oak woodland, eucalyptus woodland, disturbed habitat, and urban/developed habitat. The most abundant vegetation community on the Preserve is Diegan coastal sage scrub, which makes up approximately 417.20 acres or 70% of the total area. Floristic surveys documented 355 plant taxa occurring on site. These include both native and non-native species along with eleven sensitive (California Native Plant Society List 1-4) plant species, including: desert fragrance (Ambrosia monogyra), San Diego needlegrass (Achnatherum diegoensis), Palmer's sagewort (Artemisia palmeri), San Diego sunflower (Bahiopsis [Viguiera] laciniata), delicate clarkia (Clarkia delicata), Palmer's goldenbush (Ericameria palmeri var. palmeri), chocolate lil