Bennet Goldstein

Wisconsin Watch

March 25, 2026, 5:02 a.m. CT

Wisconsin wildlife advocates weighing how beavers, trout can coexist

The proceedings of a state beaver committee have attracted the attention of both advocates and wildlife managers across the country. The group is developing recommendations for the next decade of beaver policy in Wisconsin — a state whose trapping program has been accused of resting atop fishy foundations.

Researchers and conservationists serving on the advisory committee — primarily composed of Wisconsin Department of Natural Resources staff, federal and tribal representatives, and members from environmental and trade groups — are urging Wisconsin wildlife regulators to shift longstanding beaver management policies that frame the critters as a nuisance species.

The call to reevaluate the state’s beaver strategy comes as the Upper Midwest increasingly experiences the destructive impacts of climate change like droughts and flooding. Even wildfires, endemic to the American West, are now creeping eastward.

Beavers could present an opportunity, as the wetlands they create are more resilient to fluctuations in the ecological conditions that threaten plants and animals.

“There are a lot of problems that beavers cannot touch, and there are a lot of things that are solely our responsibility,” said University of Minnesota ecohydrology professor Emily Fairfax, who has helped review several state beaver management plans. “But beavers can fix a lot, and beavers can be our partners if we let them in the places we need them.”Need a news break? Check out the all new PLAY hub with puzzles, games and more!

Wisconsin, like other states, contracts with the U.S. Department of Agriculture’s wildlife services program to remove beavers and their dams each year. In 2024, the USDA killed nearly 2,800 beavers in Wisconsin, second only to North Carolina’s 4,200.

Neighboring Minnesota also removed beavers — almost 1,400 — and down south, Mississippi cleared about 2,100. Several hundred other animals, like river otters and muskrats, are secondary trapping casualties.More: Smith: Love them or hate them, beavers are here to stay in Wisconsin

USDA’s work in Wisconsin, like most states that contract with the federal agency, focuses on abating transportation and flooding hazards and protecting timber stands.

But Wisconsin also stands out among its Midwestern peers in the extent of removal, the millions of dollars the state has spent over the years to do so, and the rationale underlying some of its policies.

Controversially, about a third of the sites where the USDA traps beavers in Wisconsin are managed in the name of protecting the state’s prized coldwater trout streams.

In 2025, the federal agency trapped and cleared dams across more than 1,550 miles of coldwater streams. At least two other states, Minnesota and Michigan, have also employed the USDA for the same purpose.

Wisconsin prioritizes maintaining free-flowing conditions on the waterbodies, partly to appeal to its customers’ fishing preferences. But the strategy has faced increasing scrutiny. Even anglers are divided over the issue.

Some beaver advocates say Wisconsin’s conservation agency, which is charged with protecting and enhancing natural resources, shouldn’t let commercial interests unduly guide its decisions.

The DNR doesn’t confidently know the size of the state’s beaver population. Most states don’t track population numbers given beaver abundance and budget constraints.

The DNR discontinued aerial surveys in 2014, which was itself an incomplete assessment. Agency staff currently estimate trends and harvest impacts using trapper surveys and voluntary reporting of annual take. Staff believe the population remains stable statewide, or is even growing.

But conservationists are calling on the DNR to conduct a comprehensive survey using sophisticated methods, such as a tool developed by Fairfax that utilizes computer-assisted aerial beaver dam mapping.

Without obtaining a reliable estimate, conservationists say, it’s impossible to devise a scientifically sound wildlife management plan.

Beaver policy impacts understudied

Beaver advocates face decades of institutional consensus in Wisconsin that beavers degrade stream habitat and threaten wild coldwater fisheries by warming water temperatures, blocking fish passage and plugging coldwater streams with silt.

When unobstructed, coldwater streams, which tend to contain few fish species, flow fast and hard.

“The option for lethal removal of beavers is an important tool that should remain available for resource managers,” DNR scientist Matthew Mitro told the state’s beaver management committee in October.

Since 2018, he has led a multi-year coldwater stream project across the state. Based upon the results, DNR scientists concluded beaver dams posed more negative impacts than positive ones, disrupted trout survival and favored the emergence of fish species that tolerate warmer waters.

Yet critics say agency staff are managing streams for the primary benefit of one species by trapping out another and justifying the practice using research that hasn’t undergone scientific peer review.

A 2011 assessment of beaver-related research conducted in the Great Lakes region found that 72% of claims concerning beavers’ negative impacts are speculative and not backed by data, while the same held true for 49% of positive claims. The negative claims included the ideas that beaver dams warm streams and block trout passage.

Wisconsin wildlife managers often respond that academic literature largely has been conducted in the western United States and can’t be directly transplanted to Wisconsin’s comparatively flat landscape. 

That is all the more reason to get off our haunches and wade into beaver ponds, Fairfax said. She supports using more robust tools like 3D temperature maps and study designs that measure entire beaver complexes, rather than on the scale of individual ponds.

“This isn’t to criticize people making these speculations,” she said. “This is to point out a data need. So when we are thinking about managing beaver and writing beaver management plans, we should write in a need for science.”

USDA staff note that beaver clearing occurs on only about a tenth of coldwater streams in Wisconsin and impacts only 2.4% of beaver habitat statewide.

Targeted management is distinct from recreational or occupational beaver trapping and natural predation, Fairfax noted. Trapping and predation, which occur across a general swatch of ground, can be sustainable, while targeted stream-wide depopulation and dam removal can damage entire ecosystems.

It’s also possible that stream clearing prevents beavers from moving to parts of Wisconsin where they are wanted and could thrive with fewer conflicts.

Even flood-prone cities could reap the benefits.

Thunderstorms wreaked havoc in southeastern Wisconsin last summer, bringing more than 14 inches of rain to some parts of Milwaukee within 24 hours on Aug. 9-10. Roughly 2,000 homes sustained major damage or were destroyed in the ensuing floods, and the county now faces more than $22 million in public infrastructure repairs after being twice denied federal disaster assistance.

Beaver dams can dissipate torrents of water when the sky opens.

Using computer models, University of Wisconsin-Milwaukee researchers estimated that the Milwaukee River watershed could accommodate enough beaver colonies to reduce flood water volumes by 14% to 48%.

Feds assess beaver dealings

The update of Wisconsin’s beaver management plan coincides with a new USDA environmental assessment of beaver removal in the state.

The USDA decided to update its previous assessment, published more than a decade ago, after a conservation organization founded by a beaver management committee member announced its intent to sue.

In both the new and old assessments, the USDA concluded its Wisconsin trapping activities are unlikely to result in unintended declines in the state’s beaver population beyond what state wildlife managers desire to see. Even if USDA stopped trapping, the agency postulated that state or local wildlife managers would likely continue trapping with or without federal involvement, since the USDA merely serves as a contractor and doesn’t set states’ beaver policies.

The agency allocates some funding for installing flow devices that can reduce the footprint of beaver ponds by lowering water levels. The tools have limits, though, particularly in high-flow streams or infrastructure-heavy floodplains.

But nearly all beaver conflict sites that the USDA handles in Wisconsin are managed through trapping. Wildlife managers say that they need flexibility because no two beaver sites are identical.

“We’re not against beaver complexes. We’re not against ecosystem diversity, and I don’t know why people try to paint us that way,” DNR fisheries biologist Bradd Sims told the beaver management committee. “We’re an open-minded bureau that’s open to different management styles.”

Trout and beaver proponents do agree that climate change poses an existential threat. While the former group might view beavers as harmful to coldwater streams, the latter see their potential as a partner in creating resilient landscapes that can accommodate not only fish, but also frogs, turtles, bugs, bats, birds and humans.

“I’m not saying we should unemploy our human engineers,” Fairfax said. “I think that we should have our brilliant brains working in the landscapes beavers cannot. Our forests are also unhealthy. Our prairies are also struggling. Let’s put our minds to the places that beavers are not in charge of, and rest assured that the beavers can keep our rivers healthy.”