ARCHIVED REPORTS_1991_1 - Laserfiche WebLink

Home Browse Search

Valley Elderberry Longhorn Beetle The valley elderberry longhorn beetle (Desmocerus californicus californicus) is designated a Threatened species by the USFWS. This beetle is entirely dependent on elderberry shrubs for reproduction and feeding. Elderberry shrubs, in turn, are found almost exclusively in riparian habitat. Valley elderberry longhorn beetle populations have declined in the Central Valley due to the great reduction of the region's riparian habitat. Exit holes have been discovered on elderberry shrubs six miles east of the project site along Bear Creek near Lockeford and approximately seven miles north of the project site along Dry Creek (CNDDB 1991). Elderberry shrubs were not detected on the proposed project site during the survey. Therefore it is improbable that the beetle occurs in areas that would be disturbed by construction activities. Giant Garter Snake The giant garter snake (Thamnophis couchi gigas) is designated a Threatened species by the California Department of Fish and Game (CDFG) and a Candidate Category 2 species by the U.S. Fish and Wildlife Service(USFWS). The giant garter snake is aquatic and will quickly retreat to water when alarmed. They feed on carp, bullfrogs, and other fish and amphibians. During the active season (generally March through October) these snakes bask on stream banks or drape on emergent and streamside vegetation (Hansen 1982). The snakes spend the winter in dormancy, inhabiting cracks and burrows above the high water line. The former range of the giant garter snake extended from Sacramento south to Buena Vista Lake near Bakersfield (Hansen and Brode 1980). Its range and numbers have been significantly reduced by conversion of the Central Valley's marshes and riparian habitat to agriculture and urban development. Populations of giant garter snakes are still declining throughout their range (CDFG 1990). The closest record of giant garter snakes occurring near the proposed project is Coldari Marsh, approximately nine miles southwest of the transfer station (CNDDB 1991). The study area contains habitat that is minimally to moderately appropriate for giant garter snakes. Fish and amphibians in the pond and river provide potential prey items for foraging snakes. Giant garter snakes could use the river levees as basking habitat and abandoned ground squirrel burrows as hibernacula during the winter months. However, giant garter snakes are extremely shy and their numbers decline in and near urban settings (Brode pers. comm.). The probability that this subspecies inhabits the study area and uses the proposed project site is judged extremely low. Even if giant garter snakes were residents of the study area, the proposed expansion of the transfer station would not impact foraging and basking habitat, and probably would not impact hibernacula of the snakes. 1