More than 620 toads, raised and hatched by the Denver Zoo, were released earlier this month into the wild in a remote area of southwestern Utah.

The Denver Zoo
Boreal toads

The boreal toad, which is found in habitats between 7,000 and 12,000 feet in elevation in the southern Rocky Mountains, is endangered in Colorado and New Mexico, and is protected in Wyoming, according to a Denver Zoo news release.

As boreal toad numbers declined alarmingly over the past two decades, government agencies and zoos, including the Denver Zoo, have increased programs aimed at boosting wild populations.

On June 3, Denver Zoo amphibian experts Tom Weaver and Derek Cossaboon, and staff member Judy Mead, went to the Paunsaugunt Plateau and released a multitude of toads into their native range.

“As zoologists, it’s incredibly important that we apply our passion for wildlife to the animals in our care and leverage our expertise to help wild populations,” said Weaver in the news release. “This initiative really connects what we do here at the Zoo with our ongoing efforts to save wild animals, and serves as a testament to the collective expertise we share with other zoos and partners. It’s a career high.”

More than 50 percent of frog, toad, salamander and caecilian species are at risk of extinction within the next 50 to 100 years due to habitat loss, climate change, pollution and disease, according to the zoo. Chytrid fungus, in particular, is overwhelming the majority of the world’s more than 7,000 amphibian species, and is linked to severe population declines and extinctions globally.

The Denver Zoo’s boreal toad release program was aided by the U.S. Forest Service, Utah’s Hogle Zoo (Salt Lake City) and the Utah Division of Wildlife Resources.