ANN ARBOR, MI - Michigan is the Wolverine State, but there’s been no verified sighting of a wild wolverine here since 2004.

The scarcity of the animal is now official, as the U.S. Fish and Wildlife Service has designated the wolverine as an endangered species in the lower 48 U.S. states. The vicious animal that resembles a large weasel has been pushed as far west as the Rocky Mountains, according to the Associated Press.

And, ironically, due to the animal being the University of Michigan’s mascot, there may be as many wolverines in Buckeye country in Ohio as there are in Michigan. Both the Columbus and Detroit zoos have an exhibit.

The question is, why is the University of Michigan’s mascot and the namesake of the Wolverine State so rare in the state? A UM professor explained that human interference is the key factor.

“It’s the story of the other main drivers of population declines in the world, not just for wolverines, but for everything,” said Brian Weeks, who teaches and researches evolutionary ecology in the university’s School for Environment and Sustainability. “That’s habitat modification, trapping and human use, basically.”

The Associated Press reports only 300 wolverines are left living in the snowy Rocky Mountains today. Most wolverine sightings in Michigan are based on newspaper accounts or hearsay, said university mammologist Cody Thompson, so it is not clear if wolverines were ever plentiful in Michigan.

“(Research) also suggests that the assumption of established populations of wolverines in Michigan might be a product of Michigan’s geographic location serving as a trade hub for trappers in the region, which likely led people to believe wolverines existed in the state when in fact the traded furs may have originated elsewhere,” he said in a statement along with Weeks.

“Given this lack of confirmed evidence, there is little reason to think there has been a breeding population of wolverines in the state of Michigan in the last 200 years,” they added.

However, there are at least 15,000 of them in Canada, according to the Canadian Wildlife Service.

There are a few theories as to why the University of Michigan chose the wolverine nickname, from the state’s fur trading history, to 1800s settlers in the region having “wolverine-like” appetites, to Michiganders having the animal’s “tenacity and strength,” according to UM officials.

The university is part of this trapping history, as former athletic director Fielding Yost called for trappers to snag a trio of live wolverines to use as the school’s mascot in the 1920s and ‘30s.

Climate change was seen as the main threat to wolverines and was the reason the Biden administration proposed on Nov. 29 endangered species protections for wolverines, the Associated Press reports. Protections are also needed for “associated habitat degradation and fragmentation,” the proposal states.

Wolverines need snowpacks for reproduction, so climate change is definitely a threat, Weeks said. The larger issue has been humans developing more and more land throughout the Midwest, pushing the wolverine out west, he said.

“Climate change is kind of a new threat exacerbating this giant old threat that got rid of wolverines in Michigan 100 years ago,” Weeks said, adding bluntly there is no place for them to live in the state.

“We’ve destroyed all their habitat,” he said.

It is possible a wolverine or two are scattered across the state, like the one spotted in 2004 in the Thumb region, Weeks said. It’s hard to know for sure since they’re very secretive and elusive animals, he said.

“They’re sort of vagrants,” he said, adding that for being such a popular animal due to the university’s affiliation, biologists do not know much about their movements.

The overall scientific community has a growing interest in “rewilding places,” or introducing predators to habitats that allow them to flourish once again, Weeks said. It is somewhat controversial in the community, he cautioned, and he has not heard of University of Michigan working on anything like that at this time.

Weeks is very interested in climate change, as his research focus has been the phenomenon’s effect on bird populations over the last 50 years. The university’s goal to reach carbon neutrality by 2040 is one he supports.

However, the focus on carbon neutrality across the world and in the university’s sustainability goals lessens the focus on promoting biodiversity and preserving natural habitats, Weeks said.

Ultimately, humans need to address how they endangered species like the wolverine, Weeks said.

“It’s always other factors, and then climate change is contributing to existing declines,” he said. “That’s kind of scary, because it means there are other very serious problems and natural systems, but it’s also kind of encouraging because those are things we can address really easily.”

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