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California Frogs Leap Back: 3,000 Released!
26 Aug
Summary
- Over 3,000 endangered frogs released in California mountains.
- Conservation effort spans over a decade, starting in 2006.
- Fungal disease and introduced trout threaten frog populations.

In 2026, more than 3,000 endangered mountain yellow-legged frogs and tadpoles were released into California's mountain ranges, primarily in the San Bernardino and San Jacinto mountains. This release is part of a long-running conservation program led by the San Diego Zoo Wildlife Alliance, which began as a rescue effort in 2006.
The program has since reintroduced over 10,000 frogs, employing advanced breeding techniques and even assisted reproductive methods. Scientists meticulously recreate natural conditions to ensure the young frogs' health and readiness for the wild. The species, once abundant, has disappeared from 92% of its historic range.
Major threats include the introduction of trout into mountain lakes, which prey on frogs and their young, and a deadly fungal disease called chytridiomycosis. These pressures, combined with habitat destruction and pollution, have led to legal protection for both Rana muscosa and Rana sierrae species.
Monitoring of released frogs tracks their survival and adaptation. Evidence from restoration projects, such as trout removal in Sequoia and Kings Canyon National Parks, shows dramatic increases in frog populations. This recovery is crucial for both the species and the broader mountain ecosystem, where frogs serve as a vital food source.