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AUGUSTIN BERNAL MOUNTAIN BIKE TRAIL PROJECT DRAFT INITIAL STUDY 12956 DUDEK 36 April 2022 not provide aquatic non-breeding habitat. Any frogs using the site as upland or dispersal habitat would therefore not be expected to remain on site for extended periods. Trail construction would occur only between May 1 and October 31. Alameda Whipsnake Alameda whipsnake is a slender, fast-moving snake that is a subspecies of the more common and widely distributed California whipsnake (Masticophis lateralis). Its current distribution has been described as five populations within a fragmented regional metapopulation in Alameda, Contra Costa, and small portions of northern Santa Clara and Western San Joaquin Counties (USFWS 2011), as follows:  Sobrante Ridge, Tilden/Wildcat Regional Parks to the Briones Hills, in Contra Costa County (Tilden– Briones population).  Oakland Hills, Anthony Chabot area to Las Trampas Ridge, in Contra Costa County (Oakland–Las Trampas population).  Hayward Hills, Palomares area to Pleasanton Ridge, in Alameda County (Hayward–Pleasanton Ridge population).  Mount Diablo vicinity and the Black Hills, in Contra Costa County (Mount Diablo–Black Hills population).  Wauhab Ridge, Del Valle area to the Cedar Mountain Ridge, in Alameda County (Sunol–Cedar Mountain population). Alameda whipsnake primarily occurs in coastal scrub and chaparral communities, but it also forages in a variety of other communities in the Inner Coast Range, including grasslands and open woodlands (Swaim 1994). Coastal scrub and chaparral communities serve as “core areas” that serve as the center of most whipsnake activity and provide concealment from predators and foraging opportunities, but verified whipsnake observations have been made up to 4.5 miles from coastal scrub and chaparral habitat (Alvarez et al. 2005). Rock outcrops and talus slopes are often associated with occupied Alameda whipsnake habitat because they provide crevices for egg-laying sites, thermal cover, shelter, and winter hibernacula, that shelter whipsnakes from predators. Brush piles, small rodent burrows, and deep soil crevices can also provide such habitat (Swaim 1994; USFWS 2011). USFWS formally designated critical habitat for Alameda whipsnake on October 2, 2006 (71 FR 58175). PCEs of designated Alameda whipsnake critical habitat essential to the conservation of the subspecies include (1) scrub/shrub communities with a mosaic of open and closed canopy; (2) woodland or annual grassland communities contiguous to lands containing PCE 1; and (3) lands containing rock outcrops, talus, and small mammal burrows within or adjacent to PCE 1 and/or PCE 2. The project site contains suitable habitat for Alameda whipsnake and is also within Unit 3 (Hayward- Pleasanton Ridge) of USFWS-designated critical habitat for Alameda whipsnake (71 FR 58175). Most of the existing unofficial bike trail passes through coast live oak woodland with closed to semi-open canopy (PCE 2) with occasional openings supporting small areas of coyote brush scrub (PCE 1). There is also a small patch of high-quality Alameda whipsnake habitat associated with California sage scrub (PCE 1) growing on the steep and rocky east-facing slope in the western portion of the biological study area between the existing trail segments. There are several known Alameda whipsnake occurrences on Pleasanton Ridge (Swaim, pers. comm. 2021), thus the project site is contiguous with occupied habitat and high-quality scrub