The Los Angeles Zoo released 653 endangered southern mountain yellow-legged frogs into the San Gabriel Mountains this August. This release marks a significant step in the multi-year effort to restore the amphibian population to its native California streams.
The Recovery Program Infrastructure
Zoo officials credit the success of the release to their new bio-secure amphibian headstarting facility. This unit provides a temperature-controlled environment where staff can monitor the frogs from the moment they are bred and hatch. The facility features specialized tanks and life support systems that ensure optimal water quality.
Byron Wusstig, the zoo’s Curator of Ectotherms, noted that the facility is a big move for the program. The controlled setting allows the young amphibians to reach a robust size before they face the challenges of the natural world. This increased size makes them less vulnerable to predators.
Decades of Conservation Work
This latest group brings the total number of zoo-bred frogs released into the wild to 7,000 since the recovery program began. The Southern Mountain Yellow-legged Frog Recovery Program started in 2018 under the leadership of the U.S. Geological Survey. It remains a collaborative effort between the LA Zoo, the San Diego Zoo, and other regional wildlife agencies.
The species has been on the federal endangered list since 2002. These frogs inhabit streams throughout mountain ranges like the San Gabriel, San Bernardino, and San Jacinto mountains. Their appearance helps them blend into their surroundings. They sport a mix of brown, yellow, grey, red, and greenish-brown colors with dark spots, creating a natural camouflage.
Next Steps for the Species
Experts expect that stabilizing the population of these frogs will support the health of local watersheds. A balanced ecosystem benefits many other species in these mountain regions. The work is ongoing and involves more than just a single release date.
Zoo staff plan to transfer 112 additional tadpoles to the Santa Ana Zoo later this month for continued care. Members of the public can view the species at the LA Zoo’s Living Amphibian, Invertebrate, and Reptile exhibit. The broader goal remains to protect these sensitive amphibians while keeping Southern California mountain streams clean and viable for wildlife.