ENDANGERED SPECIES ACT PROFILE
PROTECTION STATUS: Not listed; candidate species
YEAR PLACED ON LIST: Candidate 2002
RANGE: The central Sierra Nevada of California, from Alpine County to Fresno County
THREATS: Introduced fish, pesticides and other airborne chemical pollutants, increased ultraviolet radiation from ozone depletion, cattle grazing, pathogens, and drought
POPULATION TREND: The Yosemite toad was historically abundant in the high country of the central Sierra Nevada, but by the early 1990s had been eliminated from about 50 to 69 percent of known historical sites. Many known large populations of toads have recently crashed by up to 99 percent or disappeared completely. Declines of the toad have been especially alarming in Yosemite National Park, with recent studies at Tioga Pass documenting wholesale population crashes.