Meet the Wyoming Toad

The Wyoming toad once flourished in the wetlands and rivers of southeastern Wyoming. Now, it is one of the most endangered amphibian species in North America.

Here are 10 facts about the Wyoming toad.

1. Biologists feared the Wyoming toad was extinct. By the mid-1970s, the population was in decline likely due to a combination of chytrid fungus, habitat alterations, pesticide use and predation. In 1984, the toad was listed as endangered under the Endangered Species Act, which protects and recovers imperiled species and the ecosystems upon which they depend.

After the toad was thought to be extinct, a small population was found at what is now Mortenson Lake National Wildlife Refuge. By 1994, the numbers had drastically dwindled, and the decision was made to bring the last remaining toads into captivity. In 2020, there were 677 individuals held in captivity. Nearly 40 years after it gained federal protection, the Wyoming toad is still with us today.

Close-up of a spotted toad in a gloved hand.

2. This species is especially small for a toad, averaging just over two inches in length. Females grow slightly larger than males. This toad can be distinguished from other toad species present in Wyoming by the small adult size and by the fused cranial crests (bony ridges on the top of a toad’s head).

3. Wyoming toads are carnivores. The Wyoming toad’s diet includes ants, beetles and a variety of other arthropods, which are invertebrate animals that have an exoskeleton, a segmented body and paired jointed appendages.

Captive Wyoming toads in a tank with worms.

4. They hibernate. Adults emerge from hibernation in May or June, after daytime temperatures reach 70 degrees Fahrenheit.

5. Prescribed fire and grazing have been used to save Wyoming toads. Studies show that the Wyoming toad requires pockets of warm, shallow water to breed. Ideally these ponds exist with a mosaic of grass and shrubland habitat containing sparse open areas for foraging and basking that are nearby denser vegetation for shade and protection from predation. Prescribed fire and grazing are part of a suite of management tools used to maintain such habitat and achieve self-sustaining populations and ultimately delist the species.

Toad basks in the sunlight.

6. Wyoming toads are extremely rare and exist mostly in captivity. The Wyoming toad formerly lived in flood plain ponds and small seepage lakes in the shortgrass communities of the Laramie Basin. The species continues to face several threats, including chytridiomycosis, a fungal disease responsible for decimating North American amphibian populations.

Recovery efforts are also hampered by a lack of suitable reintroduction sites and a small population size. In recent years, scientists have gained valuable insight into the threats facing the species, as well as new techniques and technologies for addressing these threats.

Wyoming toad poses in the water for a portrait.

7. 2020 was a good year for the Wyoming toad. The Saratoga National Fish Hatchery had the best breeding season for the toads in the history of the hatchery’s breeding program. They released over 18,000 animals of all life stages (tadpoles, toadlets and adults)! Population numbers in the wild were also good and there was breeding in the wild for the sixth year in a row.

Toad sits next to a toadstool in the sun.

8. Wyoming toads depend on wetlands for breeding. Captive breeding of the Wyoming toad has been ongoing since 1993 and now occurs at six zoos around the country as well as the University of Wyoming’s Red Buttes Biological Laboratory, Saratoga National Fish Hatchery and Leadville National Fish Hatchery.

As is the case with other amphibian species, spraying of insecticides to control mosquitoes, changes in agricultural practices, increased predation, disease and changes in habitats have been suggested as causes of amphibian decline.

Toad floats in shallow, grassy water.

9. There’s a Wyoming Toad Recovery Team. The Wyoming Toad Recovery Team consists of representatives from the Wyoming Game and Fish Department, University of Wyoming, the Association of Zoos and Aquariums, Laramie Rivers Conservation District, Wyoming Natural Diversity Database, private landowners and ranchers, the USFWS Wyoming Field Office (Ecological Service), the National Fish Hatchery System (Saratoga National Fish Hatchery and Leadville National Fish Hatchery) and the Arapaho National Wildlife Refuge complex. This team identifies and recommends priority research projects and studies to facilitate the recovery of the Wyoming toad.

10. The only wild population of the endangered Wyoming toad is at Mortenson Lake National Wildlife Refuge. It has also been reintroduced to a few privately owned properties as part of a Safe Harbor program to help recover the species. Most of the remaining toads are in captivity.

Mortenson Lake National Wildlife Refuge, the home of the endangered Wyoming toad, at the golden hour.

Amphibian decline is a problem of global importance, with over 30 percent of species considered at risk. Loss of amphibians means a loss in biodiversity and healthy ecosystems. To learn more, visit the State of the Amphibians page.