🐸 653 frogs. One big step for a species fighting its way back. This summer, USGS scientists and partners released 653 critically endangered southern mountain yellow-legged frogs into their native habitat in Southern California, the largest release of the species to date. These frogs are part of a larger effort to rebuild populations in the San Gabriel Mountains, where the species has faced threats from wildfire, drought, disease, non-native predators and habitat loss. The work starts long before a frog reaches the mountains. Scientists and zoo partners rear tadpoles and froglets in captivity, then release them into carefully selected habitat. USGS researchers study the frogs after release to learn how they survive, grow and reproduce in the wild. That information helps scientists understand what it takes to establish healthy, self-sustaining populations. With this summer's release, more than 1,000 mountain yellow-legged frogs have now been reared and released into the San Gabriel ...