Bat Removal Laws in Wisconsin: What Homeowners Can (and Can’t) Do

Finding bats in your attic feels like an emergency, but acting too fast in Wisconsin can land you in legal trouble. Bat removal laws in Wisconsin exist because several of the state’s bat species are protected wildlife, and the wrong exclusion timing or method can violate state statute even if you’re just trying to protect your home.

Before you seal a single gap or call an exterminator, it helps to know what Wisconsin actually permits, what it restricts by season, and what happens if you get it wrong. This breakdown covers the legal status of Wisconsin’s bats, the exclusion calendar the state enforces, approved removal methods, permit requirements, and the penalties tied to illegal take under the state’s Endangered Species Law.

Are Bats a Protected Species in Wisconsin

Yes. Little brown bats and big brown bats, along with northern long-eared bats and eastern pipistrelles (also known as tricolored bats), are all threatened species in Wisconsin and receive legal protection, including the ban on exclusions during maternity seasons. The little brown bat (Myotis lucifugus) and big brown bat (Eptesicus fuscus) are the two species most likely to be found roosting inside homes and outbuildings, according to the Wisconsin DNR’s Broad Incidental Take Permit documentation, which notes the Wisconsin DNR listed four species of bats as state-threatened in 2011 because of the impending disease white-nose syndrome, including the little brown bat and big brown bat.

These four cave-dwelling species hibernate through winter, and they have been decimated by deadly white-nose syndrome. That population collapse is the direct reason Wisconsin built legal protections around bat exclusion timing rather than leaving removal entirely up to homeowner discretion. Under the state’s Endangered Species Law, bats in Wisconsin are protected and it is illegal to kill them, which is why every legal removal method in this guide centers on eviction rather than extermination.

If you’re dealing with other nuisance wildlife on your property alongside bats, Wisconsin’s broader framework for handling problem animals is worth reviewing in this overview of wildlife removal laws in Wisconsin, since many of the same permitting principles apply across species.

Is It Legal to Remove Bats From Your Home in Wisconsin

Removing bats from your home is legal in Wisconsin, but only through a specific process the state calls exclusion, not through killing, trapping, or sealing bats inside a structure. The Wisconsin DNR explains that in order to get the bats out, an eviction or exclusion should be completed as bats in Wisconsin are protected and it is illegal to kill them, and eviction involves installing one-way doors that allow the bats to leave but not re-enter the building.

You can complete this work yourself or hire a wildlife control operator, since there are many nuisance animal control operators in the state who will do bat exclusion for a fee if you cannot or don’t wish to exclude the bats yourself. What you cannot legally do is use lethal methods or block bats inside a roost to die, since that constitutes an illegal take under state law rather than a permitted exclusion.

Pro Tip: If you rent your home, contact your landlord before starting any exclusion work. The Wisconsin Humane Society recommends this step because property owners may have their own contractors or obligations tied to the building.

For a broader look at how Wisconsin treats problem wildlife beyond bats, including raccoons, squirrels, and birds, the state’s nuisance wildlife laws in Wisconsin outline similar permitting logic that carries over to bat cases.

Bat Exclusion Season and Restricted Dates in Wisconsin

Timing is the single most important legal detail in Wisconsin bat removal. The DNR’s current Broad Incidental Take Permit and Authorization form states that bat exclusion activities completed from August 1 through May 31 are covered automatically, while the non-exclusion period runs June 1 through July 31 to protect nursing mothers and flightless pups.

Important Note: You may see older DNR press releases and pest-control sites reference a June 1–August 15 blackout window instead of June 1–July 31. The DNR’s more recent Broad ITP/A guidance narrows the automatically covered exclusion period to August 1–May 31, so confirm current dates with the DNR’s Wisconsin Bat Program or a licensed wildlife control operator before scheduling work near the seasonal cutoff.

The reasoning behind the restriction is straightforward. Exclusions occurring during this period will separate mothers from their flightless pups, leaving the pups to die of starvation and potentially exacerbating the homeowners’ bat problem as frantic bat mothers search for an opening to reach their pups. That outcome tends to create a worse infestation than the one you started with.

Fall and spring aren’t just legally required windows, they’re also more effective. The DNR notes that effective exclusion efforts should target time periods in the fall and spring where temperatures are consistently above 50°F as bats are generally active at temperatures above that level. Excluding bats before they’ve fully left for hibernation, or before they’ve returned for summer, defeats the purpose of the one-way door.

Separately, if you ever explore caves or mines in Wisconsin, note that the DNR asks people not to enter underground sites with bats from October 1 through May 15 to avoid disturbing hibernating bats. That’s a different restriction than home exclusion timing, but it reflects the same conservation priority.

Time Period	Legal Status for Standard Home Exclusion
August 1 – May 31	Automatically covered under the Broad ITP/A; no individual permit needed
June 1 – July 31	Restricted; requires a filed Health Exemption Form for standard homes
Hospitals, clinics, daycares, nursing homes, restaurants	Exempt from the summer restriction without a health exemption form

Approved Bat Removal Methods in Wisconsin

Wisconsin law recognizes exclusion as the only approved removal method for protected bat species, and it defines that method narrowly. Exclusion includes sealing a building except for primary exits, which are outfitted with one-way doors that let bats exit and prevent re-entry. The materials matter too: one-way doors can be made of plastic or screening but must not cause harm to the bats.

Several common pest-control tactics are explicitly illegal when applied to bats. According to the DNR’s permit documentation, practices that cause intentional take of the bats, such as sticky traps, sealing the entry and exit points to the roost with bats inside, or large-hole netting that traps bats, are not considered exclusion methods and are in violation of Wisconsin’s Endangered Species Law.

Common Mistake: Sealing every entry point on a home before confirming all bats have left is one of the most frequent errors homeowners make. This traps bats inside walls or attics, which counts as illegal take rather than legal exclusion, even if it was unintentional.

Approved Methods	Prohibited Methods
One-way exclusion doors on primary exits	Sticky traps or glue boards
Sealing secondary entry points after bats exit	Sealing occupied roosts with bats inside
Professional wildlife control operator exclusion	Large-hole netting that traps bats
DIY exclusion following DNR timing guidance	Poisoning, trapping, or killing bats

Most entry points aren’t intentional. Bats often use entry points people intentionally leave open, such as a door or window, and unfortunately most houses have spaces unintentionally left open, including small openings or narrow gaps that lead to attics or cellars, as well as gaps around loose-fitting doors, windows, ridge caps, and utility vents. Identifying every gap before you install one-way doors improves the odds that exclusion actually solves the problem.

Do You Need a Permit to Remove Bats in Wisconsin

For most homeowners working within the approved season, no individual permit application is required. Wisconsin’s cave bats are listed as state-threatened and covered under a Broad Incidental Take Permit/Authorization, meaning all bat exclusion activities are automatically covered under this authorization except those occurring June 1 through July 31.

If you need to exclude bats during the restricted summer window because they pose a genuine health or safety risk, the process changes. If the landowner deems the bats in the home are posing a health risk, such as bats routinely entering living space, the landowner may conduct the exclusion provided they fill out and submit the Health Exemption Form, and the landowner must complete and submit the form within five days of the start of exclusion work.

Pro Tip: Missing the five-day filing deadline isn’t a minor paperwork issue. Failure to submit within that window can result in a fine, imprisonment, or forfeiture under Wisconsin’s applicable wildlife statutes.

It’s worth understanding what the permit does not cover. Physically removing the colony of bats is not included in the definition of exclusion and is not covered under the Broad ITP/A. In other words, the permit protects you when you install one-way doors and let bats leave on their own; it does not authorize capturing or relocating a colony by hand.

Homeowners weighing DIY exclusion against hiring help sometimes compare Wisconsin’s rules to other states. For context, states like Minnesota, California, and North Carolina each set their own permit thresholds for protected bat species, so rules that apply in one state won’t necessarily transfer if you own property across state lines.

What to Do If You Find a Bat Inside Your Home in Wisconsin

A single bat flying through a living space usually means it entered through an open window, door, or chimney rather than an established roost. Close interior doors to confine it to one room, open a window or exterior door, turn off the lights, and give it a quiet path to leave on its own.

Never handle a bat with bare hands. The DNR warns that people do sometimes encounter sick or dead bats and instructs the public to never pick up or handle bats without gloves. If you find one that appears sick or dead, you can report it using the DNR’s reporting form rather than disposing of it yourself.

Important Note: If a bat has had any direct contact with a person or pet, including a possible bite or scratch, this is a health and safety matter beyond the scope of general wildlife law. Contact your local health department or a medical professional promptly, since rabies exposure from bats is taken seriously in Wisconsin and elsewhere. This article provides legal and procedural information only, not medical guidance.

If bats have established a roost rather than making a one-time entry, the Wisconsin Humane Society advises checking resources before acting on your own. Bat Conservation International, Bat World Sanctuary, and the Wisconsin Bat Program’s exclusion page offer detailed information on how bats may be entering your home and how to humanely exclude them. Renters should loop in their landlord first, since it’s strongly recommended you contact your landlord as well before any exclusion work begins on a property you don’t own.

If you also handle other wildlife encounters around your property, such as animals found on roadways, Wisconsin’s roadkill laws cover a related but distinct set of reporting and handling rules.

Penalties for Illegal Bat Removal in Wisconsin

Wisconsin’s Endangered Species Law backs its exclusion rules with real enforcement teeth. Under state statute, it is illegal to take, transport, possess, process, or sell any wild animal on the Wisconsin Endangered and Threatened Species List, and take is defined as shooting, shooting at, pursuing, hunting, catching, or killing. Because Wisconsin’s protected bat species fall on that list, sealing a roost with bats inside or using lethal removal methods exposes you to prosecution under this law.

Courts have financial tools available beyond a base fine or forfeiture. The wild animal protection surcharge under Wisconsin law adds $875 for any wild animal that is an endangered species protected under s. 29.604, the same statute that establishes Wisconsin’s threatened and endangered species list, including its protected bats.

Paperwork failures carry consequences too. The DNR’s permit form warns that failure to comply with any provisions of the permit, or failure to submit the health exemption form within five working days when a human health or safety issue is involved during the non-exclusion period, may result in permit revocation and a fine, imprisonment, or forfeiture. Separately, take that isn’t reported within the required window is not legally covered and is in violation of the Wisconsin Endangered Species Law.

Enforcement extends to seizure. Wisconsin conservation officers have authority to act on suspected violations, and an officer or agent may, without a warrant, arrest any person the officer has probable cause to believe is violating this section in their presence, and may search the person or business records and seize any wild animals, wild plants, records, or property used in connection with the violation. Seized items don’t simply get returned. Goods, wild animals, or records seized are held by the department pending court proceedings and shall be forfeited to the state for destruction or disposition as the department determines appropriate.

These penalties sit alongside Wisconsin’s broader wildlife protection framework. If you’re researching how the state treats mistreatment or illegal handling of animals more generally, the animal cruelty laws in Wisconsin outline a parallel set of consequences that can intersect with wildlife violations in some cases.

Bat removal laws in Wisconsin exist to balance a real homeowner problem against a genuine conservation crisis. White-nose syndrome has already pushed the state’s most common house-dwelling bats onto the threatened species list, which is why the exclusion calendar, the permit exemptions, and the penalties all point toward the same goal: get bats out of your living space without wiping out a colony that’s already struggling to survive. When in doubt about timing, documentation, or method, a licensed Wisconsin wildlife control operator or a call to the DNR’s Bat Program can keep your project both effective and legal.