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3 Animals On Wyoming’s Endangered Species List

Graphic Courtesy Will Gatchel

Wyoming became the 44th state in 1890, some four years after it was first designated as a U.S. territory. The same year, it would receive its nickname as the Equality State — it was the first state to grant full voting rights to women. Today, the landlocked state in America’s Mountain West region sports a population of approximately 581,000, and its stunning mountain ranges, sprawling valleys, and beautiful parks draw in thousands of visitors every year.

Considering that some 30 million acres, or a little less than half of Wyoming’s total lands, are owned by the federal government, there are a lot of places to explore. However, there are a lot of animals to protect, too. 

The Wyoming Ecological Services Field Office is tasked with conserving, protecting, and managing species in the state listed under the Endangered Species Act (ESA).

Passed into law in 1973, the ESA maintains a list of threatened species of fish, wildlife, and plants, designating them based on criteria as either endangered, threatened, experimental populations, or candidate species

Of the more than 1,000 plant, wildlife, and fish species currently listed on the ESA, 17 can be found in Wyoming. Keep reading to learn more about the past, present, and future of three species: the Grizzly Bear, Wyoming toad, and Preble’s Meadow Jumping Mouse. 

Grizzly Bear

Photo Courtesy marneejill

Encountering a hungry grizzly bear (Ursus arctos horribilis) in the wild is definitely a threat to a human encountering it. However, historical hunting and trapping have led to the grizzly bears’ status as threatened under the ESA. Conservation efforts through the decades have led to tremendous success in the recovery of grizzly populations from their all-time low in the early 1980s. In fact, the bears can now be found in many parts of Wyoming’s northwest and have actually been delisted and relisted from the ESA two separate times. 

Unfortunately, the fate of grizzly bears in the state is now largely at the hands of something they themselves cannot comprehend: legal matters. Many of the large mammals, which can live more than 30 years, roam or reside in Yellowstone National Park, located partially in Wyoming’s northwest corner. 

The good news is that the grizzly population in the park and its surrounding areas, called the Greater Yellowstone Ecosystem, has nearly doubled its original repopulation goal of 500 bears.

The bad news is that grizzly bear recovery has almost been too good, leading state officials to petition the U.S. Fish and Wildlife Service (USFWS) to remove the animal from any ESA protections. 

Environmental and wildlife advocacy groups have pushed against the petition, which would ultimately lead to a state-managed hunting program to cull grizzly populations. However, for now, grizzly bears are still listed as “threatened” under the ESA and remain one of the most famous examples of wildlife conservation success. 

Wyoming Toad

Photo Courtesy Michael D’Agostino/USFWS

The Wyoming toad (Bufo hemiophrys baxteri) stretches only two inches at full length. The wart-covered, brown-shaded toad might not win any “cuteness” awards, but its appearance does help it hide from would-be-predators like skunks, weasels, coyotes, and badgers. 

Once common in an abundance of locations throughout Wyoming, the toad is now considered one of the rarest and most endangered amphibians in North America. After a steep population decline in the 1970s, the Wyoming toad was officially listed as endangered in 1984 and has retained that status ever since. 

The species was actually thought to be extinct for a few years after being designated as endangered, but a small population was found in Mortenson Lake in 1993.

That discovery led to the establishment of the Mortenson Lake National Wildlife Refuge, which was created to support the fledgling Wyoming toad population at the site. In the following decades, the area has remained closed to the public to protect the endangered amphibians, which, due to their slim chance of survival, all exist in captivity or refuges today.   

The most promising hope for a return to past population levels for the species probably lies with the Saratoga National Fish Hatchery. The hatchery, founded in 1911, is well-known for maintaining one of the country’s biggest lake trout broodstock populations. It has also been breeding, rearing, and studying a captive population of Wyoming toads. Eventually, the program will begin reintroducing the endangered amphibians into the wild.

Preble’s Meadow Jumping Mouse

Photo Courtesy Robert Schorr/Colorado Natural Heritage Program

Despite what its name suggests, the Preble’s meadow jumping mouse (Zapus hudsonius preblei) isn’t actually capable of jumping over meadows — at least not on record. However, the small mouse does have an incredible leaping ability. 

Reaching approximately nine inches in length at adulthood, the small mammals can jump up to three feet into the air when evading predators. This jumping ability is partially explained by their hind feet, which are three times larger than other mice with similar-sized bodies. 

In 1899, American naturalist and conservationist Edward A. Preble first documented the meadow jumping mouse in Colorado. Later discoveries have found several subspecies of meadow jumping mice, and the kind Preble had found, native only to Colorado and Wyoming, was therefore named after him. 

Although historical documentation shows that Preble’s variety was found throughout the two states, urban development has significantly diminished the animals’ presence in human population-dense locations.

Almost exactly 100 years after they were first documented, the Preble’s meadow jumping mouse was officially designated as threatened under the ESA in 1998

A number of population surveys over the years do suggest a brighter future ahead for the jumping mouse species. The remaining number of Preble’s mice is still low enough to maintain a threatened status but high enough for active recovery efforts to be implemented. This notion was put forth in 2016 by the USFWS through the Draft Recovery Plan for Preble’s Meadow Jumping Mouse.

“Numerous surveys conducted in the last decade lead us to believe that there are adequate numbers and distributions of Preble’s meadow jumping mouse populations present today to allow recovery of the subspecies; however, many of these populations face continued threats to their persistence,” the plan states.

It would all be a lot easier if the Preble’s meadow jumping mouse could use its leaping ability to evade not just predators but also urban development, flooding, and habitat destruction. However, for now, they’ll have to rely on the countless people and organizations working to protect them, the grizzlies, and yes, the toads.

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