The Sierra Nevada red fox (Vulpes vulpes necator), also known as the High Sierra fox, is a subspecies of red fox and one of the most endangered mammals in North America. Until recently, only a few dozen were known to exist in a remnant population near Lassen Volcanic National Park. Recent webcam discoveries of two additional surviving remnant populations near Sonora Pass in 2010 and on Mount Hood, Oregon in 2012 raise hopes for the species’ survival. The State of California banned trapping of the Sierra Nevada red fox in 1980, after annual pelt takes had dwindled to two per year by the 1970s. It is considered to be critically endangered by the California Department of Fish and Game.

On April 26, 2011, the Center for Biological Diversity petitioned the federal government to protect the High Sierra fox under the Endangered Species Act. One serious threat to the Sierra Nevada red fox is interbreeding with non-native red foxes (which have been introduced into California’s Central Valley, San Francisco Bay Area and southern California) from America’s eastern and midwestern populations.[3] With only about 50 animals remaining, the U.S. Fish and Wildlife Service announced on December 30, 2011 that it is beginning a full status review, in response to the petition.

Ref: Sierra Nevada Red Fox Information