ARCADIA, Calif. – Close to one thousand Los Angeles Zoo bred mountain yellow-legged frogs and tadpoles (Rana muscosa) will be released into a tributary to Cooper Canyon, located in the Angeles National Forest. Representatives from the U.S. Fish and Wildlife Service, Los Angeles Zoo, and Forest Service will release the tadpoles Aug. 14 as efforts to save this federally endangered species enter their thirteenth year. This marks the second year tadpoles have been released into Angeles National Forest.

“Not withstanding that it’s a federally endangered species, it’s important that we save the mountain yellow-legged frog from extinction for future generations to enjoy because it brings balance to the ecology of the national forest,” said Daryl Hodges, Angeles National Forest Fisheries Biologist.

When the species was listed as endangered in 2002, there were only 100 adults remaining in the wild. Factors contributing to the sharp decrease in population included habitat loss, pollution, and introduction of non-native predators.

It was determined by scientists captive breeding offered the best chance to save the species. Reintroduction efforts began in 2006.

Since 2006, more than 3800 captive-bred mountain yellow-legged frog tadpoles and sub-adult males have been released into their historical habitat in the San Gabriel, San Bernardino, and San Jacinto Mountains in Southern California.

Other efforts to assist in the recovery of the frog include removal of non-native fish and bullfrogs from streams in the species’ historic range; monitoring; and continued research to inform recovery actions.

Partners in recovery of the species include: the U.S. Fish and Wildlife Service, U.S. Forest Service, U.S. Geological Survey, Los Angeles Zoo, San Diego Zoo Global, California Department of Fish and Wildlife and others.