Endangered and Threatened Wildlife and Plants; Emergency Rule To List the Sierra Nevada Distinct Population Segment of California Bighorn Sheep as Endangered

We, the U.S. Fish and Wildlife Service (Service), exercise our authority to emergency list the Sierra Nevada distinct population segment of California bighorn sheep (Ovis canadensis californiana), occupying the Sierra Nevada of California, as endangered under the Endangered Species Act of 1973, as amended (Act). The Sierra Nevada bighorn sheep is known from five disjunct subpopulations along the eastern escarpment of the Sierra Nevada totaling about 100 animals. All five subpopulations are very small and are imminently threatened by mountain lion (Puma concolor) predation and disease. Because these threats constitute an emergency posing a significant risk to the well-being of the Sierra Nevada bighorn sheep, we find that emergency listing is necessary. This emergency rule provides Federal protection pursuant to the Act for this species for a period of 240 days. A proposed rule to list the Sierra Nevada bighorn sheep as endangered is published concurrently with this emergency rule in this same issue of the Federal Register in the proposed rule section.