A third of Wisconsin’s wolves killed after losing protections this year, study says

A hunt killed more than 200 wolves, and poaching may have increased, since Endangered Species Act protections ended in January.
Gray wolves were extirpated from Wisconsin in the early 1900s but returned in the 1970s from populations in Minnesota. In January 2021, they lost protections afforded by the Endangered Species Act.
Photograph by Jim Brandenburg, Minden Pictures
By Douglas Main
Published 12 Jul 2021, 12:24 BST

February was a deadly month for wolves in Wisconsin. The state issued 2,380 hunting permits, with a plan to allow hunters to kill 119 of the animals. But in fewer than three days, hunters shot or trapped 218 wolves, leading the state to close its season early. 

New research suggests the official death toll is incomplete. A paper published last week in the journal PeerJ estimates that, in addition to these fatalities, illegal poachers killed another hundred wolves, together reducing the U.S. state’s wolf population by about one-third between April 2020 and April 2021. 

And even that is likely an underestimate, according to Adrian Treves, study co-author and professor at University of Wisconsin-Madison. “We took the most conservative estimates of poaching and cryptic poaching,” or illegal hunting that goes unrecorded, he says. 

The paper estimates there are now between 695 and 751 grey wolves in the state, a decline from a population of around a thousand (or slightly more) in 2020. The Wisconsin hunt followed the Trump administration’s decision to withdraw Endangered Species Act protections for wolves nationwide, which went into effect January 3, 2021. 

Although initially the state’s Department of Natural Resources (DNR) did not plan to allow a February hunt, a legal case brought by a pro-hunting group resulted in a judge ordering the department to proceed.

This scale of hunting could have long-term consequences for Wisconsin’s wolf packs, such as fragmenting family groups, interfering with reproduction, and depressing population growth rates. 

Treves says Wisconsin serves as a cautionary tale for what can happen when protections for wolves are eased, noting similar research showing that illegal killing of wolves may rise when legal hunting is permitted. Following Wisconsin’s hunt, Montana and Idaho passed laws that slash restrictions and allow for expanded wolf hunting in each state.

To complicate matters further, the decline of the state’s wolf population goes against the state’s goal of maintaining a stable population of wolves, a top predator that helps sustain ecosystem health, Treves adds. 

The DNR did not immediately reply to a request for comment. 

A ‘black eye’ for Wisconsin

Under current state law, the DNR must hold a hunt each year, whether or not it’s justified scientifically, says Adrian Wydeven, a wildlife biologist who led the state’s wolf management program from 1990 to 2013.

In February, the DNR gave hunters the green light to use methods and practices that were previously not allowed in the state, including the use of dogs and snowmobiles, and nighttime hunting. February is the height of wolf-breeding season, which is not a traditional time for hunting because it interferes with wolves' ability to breed and produce pups, Treves says.

Hounds, which tracked a majority of the wolves killed in February, often kill multiple wolves and tend to target the alpha males and females that are vital to the pack’s survival.

Treves and his co-authors argue that the state should follow the best science-based management practices for hunting wolves, such as more carefully evaluating quotas and the amount of allowed permits. He adds that a planned November 2021 wolf hunt is “unwise,” given that “we don’t yet know the impacts of the February hunt.” 

The February hunt drew condemnation from environmental groups and scientists around the world. It was also seen as unfortunate by many wildlife managers and hunters, says Wydeven,  who currently works with the conservation group Wisconsin’s Green Fire. “A lot of hunters saw this as a black eye for hunting in Wisconsin,” he says. (Related: Montana has made killing wolves easier. Some hunters are pushing back.)

Illegal hunting on the rise

In the paper, Treves and colleagues relied on both legal hunting data and past estimates of poaching from Wisconsin and Michigan, a neighbouring state where wolves also live. 

The team ran two mathematical models to calculate changes in wolf populations when Endangered Species Act protections were removed and state management went into effect. Such shifts happened six times in the two states in recent decades, as different political administrations have changed policies. 

They then applied the models to current conditions, coming up with an estimate that around a hundred wolf deaths were caused by cryptic poaching—much of it likely occurring since November 3, 2020, when the government announced the end of the wolf’s federal protections.

Wydeven, who was not involved in the study, says the estimated declines are plausible, but he adds that he doesn’t think it’s appropriate to place all the blame on the decision to remove federal protections from the animals. Over the last couple decades in Wisconsin, about 10 percent of the state’s wolves have been illegally killed each year on average, a percentage that may have increased recently, he says.

“In [some] ways, I also find the results unsurprising—we list wolves to give them additional protection from things like poaching, so one might expect higher levels of illegal kill after delisting,” says Peter David, a wildlife biologist at the Great Lakes Indian Fish and Wildlife Commission who wasn’t involved in the research. 

Erik Olson, an associate professor of natural resources at Northland College in Wisconsin, says the decline calculated in the study may be overstated. 

Based on the Wisconsin DNR’s analysis used for establishing the original harvest quotas, Olson says he expects the wolf population dropped by roughly four to 13 percent following the hunt, and at worst by one third. He also suggests the jury is still out on how to best calculate levels of cryptic poaching in Wisconsin. 

Still missing 

Although wolves have recovered significantly in certain areas, such as northern Minnesota and Michigan’s Upper Peninsula (as well as regionally in parts of northern Wisconsin), they are still absent from the vast majority of their former range, which once stretched throughout much of North America, says David.  

For this reason, he and many other scientists believe the animals should not have lost federal protections throughout the whole country. 

But the unexpectedly high number of wolves killed this year in Wisconsin shows how wildlife can suffer when management decisions are constantly in flux between federal and state control, Olson says. This flip-flopping has also led to worsening attitudes towards wolves. 

“We need to start coming together,” Olson says, “to reduce the intensity and frequency with which this pendulum is swinging from full federal protection to state-managed harvest.” 


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