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APPENDIX I - BIOLOGICAL RESOURCES Reptiles The northwestern fence lizard (Sceloporus occidentalis occidentalis) is the most abundant reptile on the site. It is especially abundant in and around the piles of oak tree stumps. Two specimens of the northwestern pond turtle (Clemmys marmorata marmorata)were observed in the pond;presumably this species is successfully reproducing in this habitat. The shed skin of a Pacific gopher snake (Pituophis melanoleucus catenifer)was recovered from under a cut oak branch,but no snake species were directly observed during the cool fall weather period. Birds Appendix F presents a list of bird species observed during the November, 1991 survey,and during a one- day survey by the applicant's consultant (Guse, 1990). It should be stressed that the present worth of the project site as a feeding and resting habitat for migratory water birds was minimal due to the preceding five years of drought and the unusually heavy stand of cocklebur and other aggressive weed species presently occupying the lake basins. An interview with the previous property owner revealed that huge flocks of ducks used the upper lake and Canadian geese used the lakes on both northern and southern migrations (Brovelli, 1991). It should be noted that this use by waterfowl was during a period when the basin of this seasonal wetland was being farmed each summer, thus the habitat was experiencing a true wet-dry seasonal wetland cycle. The most striking avifauna element observed during the November survey was the raptor complement on the project site. Because of the continuous decrease of mature riparian woodland stands in San Joaquin and adjacent counties, any remaining substantial woodland plot functions as a biological magnet for raptor species,especially when it is situated adjacent to good rodent habitat such as moderately grazed dry and irrigated pasture. In addition to meeting this criteria, the Tracy Lakes basins appear to support a substantial small rodent population which apparently colonize this area during dry seasons and drought year sequences from the grassland/riparian edge areas. This combination of roosting and nesting sites in mature foothill/riparian woodland, coupled with adjacent grassland foraging areas, is especially important to the Swainson's hawk(Buten swainsoni), a migratory species that was not viewed during the November survey. The most abundant raptor observed in November was the red-tailed hawk (Buten jamaicensis). This is the only permanent resident soaring-type (buteo) hawk, with six to eight individual specimens seen on each tour of the site. Other raptors viewed one or more times were the northern harrier (Circus cyaneus), the black-shouldered kite (Elanus caeruleus), the Cooper's hawk (Accipiter cooperii), the American kestral (Falco sparverius), the Great horned owl (Bubo virginianus),the barn owl (7�to alba) and the turkey vulture(Cathartes aura). A large number of this latter species was observed on the site, which was once acclaimed to support the largest nesting colony of these birds in North America (Brovelli, 1990). 12