A toad that had not been seen in Yosemite National Park for 11 years was reintroduced to the park this week by San Francisco Zoo officials.
Zoo officials said in a Facebook post that 118 Yosemite toads, known by their scientific name as Anaxyrus canorus — were recently flown in and released into a park meadow once occupied by the species.
The reintroduction of the federally threatened Yosemite toad into the national park is part of a five-year project to reestablish a self-sustaining population.
(San Francisco Zoo)
It's the first time that toads bred at Yosemite Zoo have been released into the park and will be part of a five-year project aimed at reestablishing a self-sustaining population. National Park Service crews will monitor and track the toads using radio transmitters. The toads have also been microchipped, officials said.
Yosemite toads, which are stocky and have light skin full of bumps and dark spots, are found primarily at higher elevations, up to 12,000 feet. They are found only in the Sierra Nevada and can be found from Alpine County to Fresno County.
Each released Yosemite toad is implanted with a microchip for identification.
(San Francisco Zoo)
The toads, which move by walking rather than hopping, rely on spring snowmelt to reproduce and spend most of their time in underground burrows, which they also use in winter when they hibernate for up to eight months.
But climate change, wildfires and amphibian diseases have cut the toad's population in half, prompting wildlife officials to federally list it as an endangered species in 2014.
Yosemite National Park officials say a lack of winter snow in previous years and higher temperatures have dried out breeding ponds, preventing tadpoles from developing into toads. Pollution and diseases such as chytrid fungus have also played a role. In 2013, the Ring fire in Yosemite National Park destroyed much of the toad's habitat.
Amid such losses, the San Francisco Zoo's conservation team began breeding hundreds of the tiny toads with the goal of reintroducing them to Yosemite National Park, where officials say the animal was first discovered.
Yosemite toads play an important role in the high-altitude food cycle. They act as predators of terrestrial invertebrates such as flies, worms, and spiders, and also serve as food for mountain yellow-legged frogs and garter snakes.
Yosemite toads are primarily found at higher elevations. They are only found in the Sierra Nevada and can be found from Alpine County to Fresno County.
(San Francisco Zoo)
Authorities hope the reintroduction of the toad will bring balance to some of these high-altitude ecosystems.
The zoo project is being developed in collaboration with the National Park Service, Yosemite Conservancy, U.S. Fish and Wildlife Service, California Department of Fish and Wildlife, and the U.S. Geological Survey.
