Endangered Sierra Nevada yellow-legged frogs were once abundant in the mountains in and around Yosemite, with hikers seeing hundreds of the amphibians at a time on the shores of alpine lakes.

Surveys in the mid-2000s, however, showed that the species was rapidly declining and heading toward extinction. The frogs are a keystone species in Yosemite, filling a vital role as both predator and prey, and playing a crucial part in natural nutrient and energy cycles. Their decline, therefore, has notable consequences for the broader Sierra Nevada ecosystem.

Starting in 2006, Conservancy donors have funded multiple projects to help restore Yosemite’s populations of Sierra Nevada yellow-legged frogs. Over the years, donor support has helped scientists introduce frogs into predator-free lakes, study the species’ genetic structure and diversity, and engage young people in hands-on amphibian conservation activities. In 2015, with support from Conservancy donors, Yosemite scientists used environmental DNA (eDNA) as a non-invasive way to identify lakes that can serve as safe, suitable habitats for new frog populations, a cutting-edge technique that could be used to protect other endangered wildlife. In 2016, biologists drew on years of successful work with Sierra Nevada yellow-legged frogs to continue supporting the recovery of that now-rare amphibian while also restoring two other species: the California red-legged frog and the western pond turtle.

Heather McKinney

Aquatic Ecologist, Yosemite National Park

Project Notes

We know that if we restore these habitats for the frogs that we are going be able to increase the number of healthy, viable populations in Yosemite. Hopefully we can keep this species from going extinct.