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APPENDIX I - BIOLOGICAL RESOURCES As already stated,the restricted time period for this survey during an "off season" for en route migrants and summer breeding species severely inhibits extensive comment on the total avian habitat complex of this site at this time. Observations by local avian groups were usually limited to woodland birds, primarily during their spring migration(Yee, 1991). Especially troublesome is the fact that a state-listed threatened raptor, the Swainson's hawk, is a migratory species which spends the mid-fall through mid-spring season in Central and South America. A discussion of this hawk,based upon previous reports and publications, is provided below. Mammals A list of mammal species observed directly or indirectly (tracks, scat, burrows, etc.) is provided in Appendix F. The most conspicuous native mammal on the site is the black-tailed deer (Odocoileus hemionus columbianus)which relies mainly on several brush species, including poison oak, for its main browse or woody plant food. On the project site, the deer is in partial competition with the cattle that range freely throughout the riparian woodland and browse heavily on green brush species in the fall after all the green grass has dried. Many portions of the grassland, oak savanna and seasonal wetland areas contain numerous signs (burrows,runways, etc.) of rodents such as the California meadow vole(Microtis californicus),Botta's pocket gopher (Thomomys bonae), and in sparsely vegetated areas, the California ground squirrel (Spermophilus beecheyi). This apparently strong rodent prey complement forms the primary consumer link on the food chain upon which many species depend, such as the hawk and owl species previously mentioned, plus mammalian carnivores, such as coyote (Canis latrans), gray fox (Urocyon cinereoargenteus),badger (Taxidae taxus), and raccoon (Procyon lotor). Endangered and Threatened Species Plants None of the species reported (Muick, 1989) or those observed in this present survey are listed as endangered or threatened in the category lists 1 and 2 by the California Native Plant Society. This includes the three vernal pool species reported in the Muick paper which is noteworthy since this particular type of habitat often supports protected species. Unfortunately no dates are given for the latter survey, although the publication date of May 8, 1989 indicates that all field work was completed before that time. Given the minimal germination success of wild seeds during the past several drought years, the possibility remains that one or more protected annual forb has gone undetected, and a full spring season plant survey would confirm the presence or absence of protected plant species on the site. 13