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offers all three such habitats, and during the course of this study, the northwestern pond turtle was observed in the Beaver Pond,South Tracy Lake, and two inshore sites on the Mokelumne River adjacent to Brovelli Woods. Like the bullfrog,the South Tracy Lake population migrated in early spring to this site from the Beaver Pond and,perhaps, the river as well. The pond lake and the inshore zone along the river appear to be prime habitats for this turtle which feeds primarily on small fish, tadpoles and frogs. A concentrated effort was directed towards determining the status of the giant garter snake (Thamnophis couchi gigas), a state-listed threatened species whose geographic range includes the project site. This snake is a fish feeding specialist, and thus the Beaver Pond with its abundance of fingerlings was assumed to be the most likely habitat area. The shoreline of this site was surveyed during May and June 1992 by placing a series of plywood sheets, approximately 2 X 4 feet in area, over low growing vegetation near the water edge. Such objects provide retreat cover for resident snakes, and periodic inspection under these sites will eventually produce an inventory of local snake species as well as assorted lizards and rodents. Several specimens of the Pacific gopher snake (Pituophis melanoleucus catenifer)and the valley garter snake(Thamnophissirtalis fttchi)were recovered. No giant garter snakes were observed under the boards or at any other point around the pond shoreline. Birds Nearly one third of all birds observed on the site were water-dependent species and present on the site because of the variety of aquatic habitats. Chief among these are the Tracy Lakes. Their extensive shallow inshore zones afford excellent foraging opportunities for dabbling ducks such as mallard,northern pintail, American widgeon,northern shoveler, wood duck, and the teal species. In contrast, the deeper central lake waters provide both foraging sites for diving duck species (canvasback, ringneck,ruddy)as well as the pied-billed grebe. Most of these species were also observed on the Beaver Pond along with fish-eating birds, such as the common merganser,the double-crested cormorant,and several egret and heron species. The latter also moved to the Tracy Lakes in large numbers during July and August when water levels lowered and an abundant bullfrog tadpole population was present. The major use of the Tracy Lakes system by waterfowl was as a winter and early spring feeding and resting area before the migratory flight to northern nesting grounds. However,pairs of several species remained to nest and molt here. These included ten pair of mallards, four pair of wood duck, and four pair of cinnamon teal. The hens of these species raised nearly 100 offspring to maturity on the project site. The drakes, which take no part in raising the ducklings,also utilized the lakes as a sanctuary area during early summer when they, as well as the hens, molt all of their flight feathers and must have large open water areas for protection. A summary of waterfowl species observed from March through June, 1992,is presented in Table 4.7-1. It should be noted that the accuracy of these counts varied from visit to visit and was dependent upon how successful the observers were at counting the birds without disturbing them. The survey began after the close of the hunting season, and the appearance of the human form,even at a considerable distance, was usually sufficient to put large flocks into flight. The most successful technique was to use the larger groves of trees as blinds and count with the aid of powerful binoculars and a spotting scope while peering around a large trunk or brush patch. 12