Amphibians and Aquatic Wildlife Restoration

Project overview: Restore imperiled native aquatic wildlife populations by monitoring species’ status and reintroducing Sierra Nevada yellow-legged frogs, California red-legged frogs, Yosemite toads, and western pond turtles to healthy lakes and meadows. 

How your support helps: Amphibian and aquatic wildlife populations are threatened around the globe, as habitats are destroyed or deteriorate, and invasive diseases and species arrive. Since the late 1990s, Yosemite Conservancy donors have supported efforts to study and save Yosemite’s native aquatic species through surveys of lakes, ponds, and meadows, as well as ambitious captive rearing and reintroduction efforts. In recent years, donor-funded work has focused on three imperiled amphibians: Yosemite toads, Sierra Nevada yellow-legged frogs, and California red-legged frogs.  

• Yosemite toads: Through Conservancy-supported research, scientists have increased their understanding of the park’s population of Yosemite toads, a rare and endemic species. In June 2024, the National Park Service conducted a reintroduction of Yosemite Toads to meadows near White Wolf — the first-ever attempted reintroduction for this species.  

• Yellow-legged frogs: In 2013, the Conservancy began funding targeted efforts to restore high country lakes and reintroduce once-common, now-endangered Sierra Nevada yellow-legged frogs. That effort has resulted in a measurable increase in yellow-legged frog numbers in Yosemite — one of few examples of a frog population rebounding, as amphibians decline worldwide.  

• Red-legged frogs: In 2016, with support from donors, scientists turned their attention to another imperiled amphibian, California red-legged frogs, which hadn’t been seen in the park in half a century. In recent years, biologists have reintroduced thousands of red-legged frog eggs, tadpoles, and adults in Yosemite Valley, where the species is now successfully reproducing and regaining a foothold in the ecosystem.  

The park’s successful amphibian work is anchored in innovative approaches to wildlife research and restoration. With donor support, scientists have been able to identify healthy habitat; study the prevalence of chytrid fungus, which causes the potentially deadly amphibian disease chytridiomycosis; use tiny microchips to monitor red-legged frogs; partner with the San Francisco Zoo to raise young amphibians in a protected space; and more.  

This year: In 2025, park teams will uplift species’ resilience and stewardship with the first reintroductions of foothill yellow-legged frogs, and the continued reintroduction of California red-legged frogs and Sierra Nevada yellow-legged frogs to native habitat in park meadows. Biologists will continue monitoring species and reintroduction successes, and they will monitor western pond turtles with the goal of reintroducing them in the coming years. 

Project partners: Yosemite National Park; University of California, Santa Barbara; and San Francisco Zoo