Hundreds Of Mountain Yellow-Legged Frogs Leap Back Into Wild In SoCal

SAN DIEGO, CA — Hundreds of mountain yellow-legged frogs have jumped back into the wild, thanks to Birch Aquarium and other organizations working together to save the endangered species.

More than 350 frogs were reintroduced into the wild in Southern California's San Bernardino Mountains, marking one of the largest releases to date. The release also represented a milestone for Birch Aquarium as it was the aquarium's first-ever species reintroduction.

Birch Aquarium at Scripps Institution of Oceanography at UC San Diego, in collaboration with San Diego Zoo Wildlife Alliance, the University of California, Los Angeles, Big Bear Alpine Zoo and additional partners, released the frogs into a wildlife preserve managed by The Wildlands Conservancy. This effort was part of a long-running recovery program with partners at the U.S. Fish and Wildlife Service, the U.S. Geological Survey, the California Department of Fish and Wildlife and the U.S. Forest Service.

"It was an incredibly exciting and emotional day for our team, as releasing these frogs into the wild marks a historic first for Birch Aquarium," said Sean Bruce, assistant curator of fishes and invertebrates. "We have been raising these frogs for more than a year, and to finally reach this milestone is truly remarkable!"

Of the released frogs, 220 were raised behind the scenes at Birch Aquarium, while the rest were raised at SDZWA and UCLA.

"This release was made possible by the extraordinary dedication of our husbandry team and the invaluable collaboration of our partner organizations in this recovery project," Bruce said. "Our shared passion and expertise made this success possible, and we hope these frogs thrive here for many years to come."

The release marked the second introduction of these frogs to the lake within the wildlife preserve managed by The Wildlands Conservancy. More than 70 frogs were first released in 2023, and the recent August release added even more to the area.

Researchers plan to continue to monitor and track the frogs at the release site multiple times each year, with the goal of supporting the release of more frogs in the future, according to Birch Aquarium.