Born in a zoo, released into the San Gabriels, a rare Los Angeles frog bounces back

Ian Recchio, left, curator of reptiles and amphibians at the Los Angeles Zoo, and colleague Greg Pontoppidan transfer several hundred yellow-legged frog tadpoles from coolers to backpacks to be released.

Ian Recchio, left, curator of reptiles and amphibians at the Los Angeles Zoo, is photographed as he transfers the yellow-legged frog tadpoles.

Tim E. Hovey, left, senior environmental scientist with the California Department of Fish and Wildlife, helps Ian Recchio, curator of reptiles and amphibians at the L.A. Zoo, carry a cooler backpack containing some of the yellow-legged frog tadpoles to the release site.

Tim E. Hovey, senior environmental scientist with the California Department of Fish and Wildlife, monitors a bag containing yellow-legged frog tadpoles.

Adam Backlin, a USGS ecologist, carefully releases some of several hundred yellow-legged frog tadpoles raised in captivity at the Los Angeles Zoo.