Help Wisconsin Bats During International Bat Week 2025

MADISON, Wis. – The Wisconsin Department of Natural Resources (DNR) encourages Wisconsinites to take action to help bats during International Bat Week, Oct. 24-31, 2025, and attend an educational bat event throughout the state in October.

As a group of mammals, bats are unique and fascinating; they’re also extremely important members of our natural world. They are vital to many ecosystems and provide significant positive environmental, economic and public health benefits. For example, insectivorous (bug-eating) bats consume large numbers of agricultural pests, saving farmers and forest-owners billions of dollars every year.

Of the eight bat species found in Wisconsin, four are state-threatened species – the big brown bat, little brown bat, northern long-eared bat (also federally endangered) and tricolored bat. Another, the silver-haired bat, is of special concern, meaning the population is declining and in need of conservation action.

The decline of bats in Wisconsin is primarily due to white-nose syndrome, a disease caused by a fungus that attacks the bare skin of bats during hibernation each winter. The disease exhausts their energy stores and leaves them vulnerable to starvation before their insect diet becomes available in the spring.

Fortunately, after experiencing steep declines since 2014, when white-nose syndrome first arrived in Wisconsin, recent Wisconsin Bat Program survey counts show rebounding numbers of little brown bats at some significant roost and hibernation sites across the state.

According to DNR conservation biologist and bat program hibernacula specialist Jennifer Redell, many of these sites offer ideal conditions for little brown bats and were known to hold large numbers before white-nose syndrome arrived in the state.

“Due in part to those large aggregations, we are still seeing significant numbers holding on, and our annual counts of little brown bats keep increasing,” she said. “Most of those sites are former mines, and despite being relics of industry, it’s important that we recognize them as habitat critical to a significant proportion of the nation’s little brown bats. The sites need entrance stabilization and maintenance to remain accessible for these huge bat populations for generations to come.”

Despite the recent glimmers of population recovery in little brown bats, there’s still a long way to go. Hibernating bats are still stressed by white-nose syndrome each winter, and species like the tricolored bat and northern long-eared bat have not shown similar signs of recovery.

Attend An Educational Bat Event

There are currently 46 bat events scheduled across 29 counties, and more will be added throughout the month of October.

Check BatWeek.org’s events page and search “Wisconsin” to find an event near you!

A few events that we recommend:

• Bats Love Yellowstone Lake State Park, Oct. 11, 5 p.m. – 6 p.m.
• Bats: Myths, Mysteries, and Marvels, Shawano Public Library, Oct. 13, 6:30 – 7:30 p.m.
• Bats of Wisconsin Talk & Walk, Richard Bong State Recreation Area, Oct. 24, 5 – 7 p.m.
• Evening Bat Walk with the University of Wisconsin Bat Brigade, Oct. 25, 6:30 – 9 p.m.
• Bats of Wisconsin, Superior Public Library, Oct. 27, 6:30 p.m. – 7:30 p.m.

Tips To Help Backyard Bats

• Build and put up your own bat house.
• Plant native plants that are foundational to a healthy backyard ecosystem.
• Maintain an insecticide and herbicide-free yard. They harm bats through their diet.
• Humanely exclude bats from homes and buildings.

Volunteer And Support Opportunities

• Become a Wisconsin Bat Program volunteer and participate in roost or acoustic monitoring.
• Sign up for email updates about bats and bat conservation.
• Donate to the Endangered Resources Fund to support threatened and endangered species and habitat protection in Wisconsin.

For more information about bats, visit the Wisconsin DNR’s Frequently Asked Questions webpage.

NOTE: This press release was submitted to Urban Milwaukee and was not written by an Urban Milwaukee writer. While it is believed to be reliable, Urban Milwaukee does not guarantee its accuracy or completeness.