Birch Aquarium Leaps Into Frog Conservation
The aquarium joins collaborative effort to save the endangered Mountain Yellow-legged Frog.
Photos: Jordann Tomasek, Birch Aquarium
A new conservation chapter begins for Birch Aquarium at Scripps Institution of Oceanography at UC San Diego as it hops into action to help save the endangered Mountain Yellow-legged Frog. The aquarium joins ongoing efforts to raise and recover this native California frog species.
“Birch Aquarium is proud to join this collaborative effort to help save a species that desperately needs our help,” said Sean Bruce, Assistant Curator of Fishes and Invertebrates. “This issue hits us close to home, so we’re excited to make a meaningful, positive impact on wild frog populations.”
To help ensure this species' survival, several government agencies, institutions within the Association of Zoos and Aquariums, universities and additional partners are working together to raise and release these frogs into the wild.* The ultimate goal is to hopefully downlist or delist Mountain Yellow-Legged Frogs as an endangered species by enhancing the genetic diversity of both captive and wild populations, optimizing reintroduction efforts, increasing wild frog populations and more!
“We have a responsibility as experts in animal husbandry, conservation and science to work to protect, understand and connect our communities with animals in need,” said Jenn Nero, Chief Animal Care, Science and Conservation Officer. “By collaborating with others, we aim to help the survivability of these important indicator species.”
Mesmerizing Metamorphosis
As part of this recovery program, the aquarium received more than 200 tadpoles from the San Diego Zoo Wildlife Alliance (SDZWA) in July 2024. In just a few short weeks, the aquarium’s Frog Care Team successfully reared these tiny tadpoles into frogs. They’re being cared for behind the scenes in an outdoor aquatic habitat designed to replicate conditions they will encounter when reintroduced into the wild.
“We’re the only partner raising these frogs in an outdoor habitat, which is pretty exciting,” said Bruce. “I love seeing their vibrant bronze, orange and yellow colors come to life and shine in the sunlight.”
As they grow, frogs undergo a truly astonishing transformation known as metamorphosis. After eggs are laid in the water, they’ll hatch into tiny tadpoles equipped with gills and a long tail perfect for swimming. Over time, these tadpoles change into froglets as they replace their gills for lungs and tail for legs. Within a few weeks, they’ve matured into fully grown frogs ready to take on life on land.
A Future For Frogs
Measuring just three inches long, Mountain Yellow-legged Frogs call the high-elevation aquatic habitats of the Southern California Mountains home. In these habitats, they once thrived, finding the lakes, ponds and pools essential for breeding and tadpole development. But that’s no longer the case.
Today, fewer than 200 adult Mountain Yellow-legged Frogs are believed to remain in their native habitat of the Southern California Mountains. This rapid decline has been driven by habitat fragmentation, disease and increasing impacts of climate change, especially droughts and wildfires. As a result, this frog is listed as endangered on the International Union for Conservation of Nature Red List of Threatened Species.
“Having less than two hundred individuals of any species is pretty dire,” said Bruce. “That’s why participating in this collaborative effort to save these frogs alongside so many remarkable partners is crucial.”
The aquarium’s next major step in supporting ongoing release efforts will be the release of these frogs into their native habitat in the Southern California mountains. While the aquarium hopes this release will take place this summer, it will ultimately depend on environmental conditions in the release zone, particularly in the wake of the recent wildfires that swept through Southern California.
Amphibians at the Aquarium
These adorable additions mark the first time the aquarium welcomed this critically important amphibian into its care! While these Mountain Yellow-legged Frogs will remain behind the scenes for ongoing conservation efforts, the aquarium hopes to create a future exhibit where guests can learn more about this critical recovery program.
These frogs are not the only newcomers to the aquarium. The animal ambassador program has also grown with the arrival of new species, including an Australian Laughing Kookaburra and a Bearded Dragon. Additional information about these animal ambassadors can be found on the aquarium’s website.
*The Mountain Yellow-legged Frog recovery program has been active since 2006, with partners joining over time to support ongoing conservation efforts. While the San Diego Zoo Wildlife Alliance serves as the lead organization, numerous key stakeholders and partners contribute to this work:
- Government agencies: U.S. Fish and Wildlife Service, U.S. Forest Service, U.S. Geological Survey, California Department of Fish and Wildlife, California State Parks
- Zoos and aquariums: San Diego Wildlife Alliance, Aquarium of the Pacific, Birch Aquarium at Scripps Institute of Oceanography and UC San Diego, Los Angeles Zoo, Omaha’s Henry Doorly Zoo, Santa Ana Zoo
- Universities: University of California, Los Angeles and University of California, Berkeley
Together, these partners are committed to ensuring the survival and recovery of the Mountain Yellow-legged Frog.
About Birch Aquarium at Scripps
Birch Aquarium at Scripps is the public exploration center for Scripps Institution of Oceanography at UC San Diego. Perched on a bluff overlooking the Pacific Ocean, Birch Aquarium features the groundbreaking work of Scripps Oceanography and UC San Diego scientists as well as conservation breeding programs and interactive exhibits. Birch Aquarium’s mission is to connect understanding to protecting our ocean planet, which it achieves through engaging hands-on learning opportunities for more than 500,000 guests and 40,000-plus pre-K-12 students each year. Visit aquarium.ucsd.edu for more information.
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