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Another invertebrate species presently under consideration for protection,the curved-footHygrotus diving beetle (Hygortus curvipes), also prefers natural pond and spring pool conditions. However, the only aquatic beetle species collected in the plankton net and fine mesh seine samples was the water boatman, a very distinct beetle with enormous swimming appendages. Fish Notes taken at an interview with Mr. Angelo Brovelli in 1990 reveal that the Beaver Pond was never purposely stocked,but instead has received all the fish species it presently supports from the Mokelumne River when it periodically overflows its banks. Five hauls with a 100 X 6 foot 1/4 inch mesh beach seine operated by students from California State University,Hayward,revealed an eight species complex in this habitat. This group is composed of bluegill (Lepomis macrochirus), redear sunfish (Lepomis microlophus), warmouth (Lepomis gulosus), black crappie (Pomoxis nigromaculatus), largemouth bass (Micropyerus salmoides), mosquito fish (Gambusia affiinis), brown bullhead (Ictalurus nebulosus), and golden shiner (Notemigonus crysoleucas). All species exhibited at least two distinct year classes, indicating that each was successfully reproducing in the pond. This group contains no native California fish species. Amphibians Only two amphibians, the native Pacific tree frog (Hyla regilla) and the introduced bullfrog (Rana catesbeiana) were observed on the site. Dip net samples in the vernal pools and fine mesh seine net hauls in the inshore areas at random points along the Tracy Lakes shorelines failed to produce the larva of any other amphibian species, thus verifying that two species of special concern, the California red- legged frog (Rana aurora draytonii) and the California tiger salamander, (Ambystoma tigrinum californiense) do not occur on the site. The distribution of the bullfrog on the project site is of particular interest in that the entire population was restricted to the Beaver Pond prior to the filling of the lakes in mid-winter. By early spring, however, a surprising number of individuals had migrated to the lake sites from the pond and possibly some backwater areas of the Mokelumne River where they proceeded to breed. The adults and their crop of tadpoles later provided food for a number of water bird species. 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. Several specimens of the northwestern pond turtle (Clemmys marmorata marmorata) were observed in the Beaver Pond, and presumably is successfully reproducing. The northwestern pond turtle and its subspecies relative, the southwestern pond turtle, represent the only native freshwater turtle species in California and are both listed as species of special concern by the California Department of Fish and Game. This species suffered a sever reduction in numbers during the last century when this once abundant reptile was captured in larger numbers for food. This was followed by a large scale reduction in habitat as extensive backwater areas in the Central Valley were drained. More recently,the conversion of open ditch irrigation lines to cement culverts has placed a high premium on shallow ponds, lakes, and protected river shorelines as habitats for this species. The project site 11