Joe Rickles

These misunderstood critters are in danger, and they need our help

Bats — nature’s only flying mammal — may seem like a creepy concept out of Transylvania, yet Wisconsin has its own species of native bats that are vital to our ecosystem. But the state’s population of these misunderstood critters is in danger, and they need our help.


The Badger state is home to eight different kinds of bats. The most common are little brown bats and big brown bats, which hibernate together underground during the cold winter months.

A close-up image of a big brown bat. Photo courtesy of Dave Redell


Bats live all over Wisconsin — maybe even in your own backyard. “If you’re there at sunset, you’ll often see lots of bats flying over Lake Mendota or Monona,” says Amy Wray, a postdoctoral research assistant at the University of Wyoming who studied Wisconsin’s bats. “They’re pretty common at Picnic Point, [which] has a little bat house, so there’s usually bats flying over the water there.”


White-Nose Syndrome is a mysterious fungal disease affecting bats that originated in upstate New York around 2007. Since then, it has spread across the country and has done significant damage to bat populations across North America. Although numbers of bats have stabilized in recent years, they are far from the pre-White-Nose years.

Bats take shelter within their dark, wooden home. Photo courtesy of Wisconsin DNR Bat Program


You don’t have to be a biologist or expert to help bats. One of the best things to do is build a bat house. Here’s some tips from conservation biologist Heather Kaarakka of the Wisconsin Department of Natural Resources.

  • Do a little bit of research into where you can place it and what type of house you’re going to build. 
  • Generally, the bigger the house the better success you have. 
  • Bats tend to like it warm. It helps them gestate quickly and helps the pups mature quickly. Paint your house a dark color.
  • Place it 10 to 15 feet in the air. Avoid putting it in a tree because trees can provide too much shade and offer easy access for predators like raccoons.

DARK page photo credit: Wisconsin DNR Bat Program