Aquarium of the Pacific reaches milestone in mountain yellow-legged frog conservation

Biologists at the Aquarium of the Pacific have reached a major conservation milestone in their effort to save the mountain yellow-legged frog. The program, now entering its fifth year, has successfully raised and released more than 1,000 frogs into the wild. This figure is more than five times the estimated population remaining in their natural habitats as of 2019.

The mountain yellow-legged frog, characterized by a lemon-colored streak on its hind legs, is considered one of the rarest vertebrates on Earth. Its population has collapsed due to a combination of wildfires, mudslides, pesticides, fungal diseases, habitat loss, and the presence of nonnative predatory species like bullfrogs and crayfish. The species was listed under the federal Endangered Species Act in 2002.

The recovery effort involves a collaborative process: frogs are bred at the Los Angeles Zoo, transferred to the Long Beach aquarium as tadpoles to undergo metamorphosis, and then returned to mountain streams in the San Gabriel, San Bernardino, and San Jacinto Mountains. A recent release included 653 individuals, with 394 having been head-started at the Aquarium of the Pacific.