Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for the Callippe Silverspot Butterfly and the Behren's Silverspot Butterfly and Threatened Status for the Alameda Whipsnake

The Fish and Wildlife Service (Service) determines endangered status pursuant to the Endangered Species Act of 1973, as amended (Act) for the callippe silverspot butterfly (Speyeria callippe callippe) and Behren's silverspot butterfly (Speyeria zerene behrensii) and threatened status for the Alameda whipsnake (Alameda striped racer) (Masticophis lateralis euryxanthus). The callippe silverspot butterfly is found at two sites on grasslands in the San Francisco Bay area. Behren's silverspot butterfly is found within coastal terrace prairie at one site in southern Mendocino County. These butterflies are imperiled by overcollecting, urban development, alien plant invasion and competition, and excessive livestock grazing. The Alameda whipsnake occurs in the northern coastal scrub and chaparral habitats of Contra Costa and Alameda counties. This snake and its associated habitat are threatened by fire suppression and related wildfire problems associated with lack of fuel reduction, urban development, genetic isolation, and excessive livestock grazing. This rule implements Federal protection and recovery provisions afforded by the Act for these animals.