Wildlife experts have taken another leap forward in their efforts to save an endangered California frog.
The U.S. Fish and Wildlife Service says 100 mountain yellow-legged frogs were released Thursday at a reserve in the San Jacinto Mountains, 100 miles east of Los Angeles.
The juvenile frogs were released into a creek at the University of California's James Reserve.
The species lives in mountain streams in the San Jacinto, San Gabriel and San Bernardino mountains but federal officials say only about 200 were left in 2003.
In recent years, hundreds have been released into the wild under a captive-breeding program.
Native frog and toad species around the country are in decline. Researchers say the reasons may include habitat loss, pesticide poisoning, disease and competition from invasive species.