The San Diego Zoo is helping save the critically endangered Southern California mountain yellow-legged frog by breeding the amphibians in Escondido and returning them to the San Bernardino National Forest.
This year, the program resulted in more than 5,600 eggs laid and the most viable embryos in a single season: nearly 1,800.
On Thursday, 200 tadpoles that hatched this year, along with 27 froglets, or metamorphs, from last year’s breeding season, were released into Fuller Mill Creek north of Idyllwild.
The frogs, which live in perennial streams in portions of the San Gabriel, San Bernardino, and San Jacinto Mountains, have been decimated by the Chytridiomycota fungus.
The U.S. Fish and Wildlife Service listed the mountain yellow-legged frog in Southern California as endangered in 2002, and fewer than 200 of the frogs remained by 2003.
“We vaccinate the frogs before release, to provide some resistance to the Chytrid fungus once they are released into the wild,” said Debra Shier, associate director of applied animal ecology at the San Diego Zoo Institute for Conservation Research. “Our goal with captive breeding and reintroduction is to facilitate species recovery by increasing the numbers of mountain yellow-legged frogs in the wild, as well as buying the species time to evolve resistance to the fungus.”
In addition to breeding the endangered frogs, the zoo participates in the field monitoring of the species, led by the U.S. Geological Survey.
