The Birch Aquarium invites animal fans to hop into its newest exhibit opening today, Imagine Wild: Mountain Yellow-legged Frog.
The Birch, at Scripps Institution of Oceanography at UC San Diego, installed the immersive experience in place of the Meditation Ocean: Aquarius Reef Base exhibit, which opened in November and closed last month. It will "transport guests to a fictional California mountainside to explore the forest, meadows and lake that form the Mountain Yellow-legged Frog habitat to discover their story of resilience, uncover the threats they face and learn how science and conservation are giving them a second chance," a statement from the aquarium read.
In 2024, the Birch joined an effort with the San Diego Zoo Wildlife Alliance, UCLA and others in raising over 200 endangered Mountain Yellow-legged Frogs from tadpoles to adults and releasing them in 2025 into the San Bernardino Mountains in a wildlife preserve managed by The Wildlands Conservancy.
It was the first species reintroduction for Birch Aquarium.
"The return of the Mountain Yellow-legged Frog took decades," said Robert Raad, senior exhibit designer at the Birch. "People with a clear vision worked to restore Southern California's mountain habitats — believing they could be healthier, more resilient, and full of life. Imagine a place where endangered plants and animals thrive. We designed this space to let guests wander through that world — uncovering the dedication and perseverance that brought it back."
The aquarium raised 220 of the frogs last year, which are native to mountain ranges in Southern and Central California. The remainder were raised at SDZWA and UCLA.
The frogs are small (between 1.6-3.5 inches long) with females larger than males. Their coloring ranges from yellowish to brown or olive with black or brown markings. The undersides of its hind legs can range from pale yellow to orange, giving them their common name. When handled, they can emit a defensive odor that smells strongly of garlic.
Imagine Wild: Mountain Yellow-legged Frog invites the public to explore the complex elements needed to create a healthy ecosystem for these endangered amphibians, as well as discovering the decades-long process of restoring a habitat and the cooperative efforts involved in bringing frogs back to the land.
You can end the experience by seeing some Birch-raised frogs up close.
Over the course of the past 100 years, around 90% of the species has been eradicated. Much of this has been attributed to introduced trout populations, which feed on tadpoles. Other factors in the population decline include pesticides (a risk for highly sensitive amphibians), a fungal disease and cattle ranching.
The species is broke up into two population segments: a northern one which has been listed as endangered since 2014; and a southern one listed in 2002. The first successful captive breeding of the frog occurred in 2009 when three tadpoles were raised at the San Diego Zoo.
Birch Aquarium opens daily at 9 a.m. with closing hours varying by day. Visit aquarium.ucsd.edu for ticket and scheduled details.
