A federal judge has ruled that the Fish and Wildlife Service must act on petitions requesting that the Yosemite toad and the Sierra yellow-legged frog be given protection under the federal Endangered Species Act. The ruling came in response to a lawsuit filed by Earthjustice on behalf of the Center for Biological Diversity and the Pacific Rivers Council.
The mountain yellow-legged frog was historically the most abundant frog in the Sierra Nevada, distributed widely in high elevation lakes and streams from Plumas to Tulare Counties. Recent surveys have found that the species has disappeared from 70 to 90 percent of its former habitat. Remaining frog populations are widely scattered and consist of few breeding adults. What was thought to be one of the largest remaining populations, containing 2000 adult frogs as recently as 1996, has collapsed to only two frogs in a 1999 survey.
The Yosemite toad was once common in the high country of the central Sierra Nevada from Fresno to Alpine Counties. As with the frog, recent surveys reveal that the Yosemite toad has disappeared from a majority of its historic breeding sites. Declines have been especially alarming in Yosemite National Park, thought to be the species' most pristine and protected stronghold. Both species have been adversely impacted by introduced fish species, which prey on larval and juvenile frogs and toads, while their habitat has been degraded by pesticide pollution, cattle grazing, pathogens, and ozone depletion.