PROTECTION STATUS: Endangered (both Southern California and Sierra Nevada populations)

PETITIONED: 2000 (Sierra Nevada population)

YEAR PLACED ON LIST: 2002 (Southern California population); 2013 (Sierra Nevada population)

RANGE: Historically, mountain yellow-legged frogs were found throughout the higher elevations in the Transverse Ranges in Southern California and in the Sierra Nevada of California and Nevada. The Sierra Nevada population is now extirpated from Nevada and from large portions of the historical range in the Sierra Nevada of California.The Southern California population is now extirpated on Palomar and Breckenridge mountains and in much of the former range elsewhere in Southern California and the southern Sierra Nevada.

THREATS: Predation by introduced trout, disease, pesticides, environmental changes from drought and global warming, and habitat degradation due to livestock grazing

POPULATION TREND: More than 93 percent of northern and central Sierra Nevada populations, and more than 95 percent of southern Sierra Nevada and Southern California populations, are already extinct.

Photo by Adam Backlin, USGS