Bats in Michigan: Where to Look and What Signs to Watch For

1. Where are bats most likely found in Michigan?

Bats in Michigan favor areas close to water and forests. Most species roost in tree cavities, under loose bark, or in man-made structures like barns and bat houses. Look for them near the Great Lakes shorelines, inland lakes, and along rivers like the Huron or Manistee. In the Upper Peninsula, the Ottawa National Forest and Hiawatha National Forest are good bets. In the Lower Peninsula, the Huron-Manistee National Forests and Sleeping Bear Dunes offer reliable sightings.

2. What time of day and season is best for bat spotting?

Bats are nocturnal. The best time to spot them is from dusk until about two hours after sunset, and again just before dawn. Spring through fall is the active season; bats hibernate in winter. May through September offers the highest activity, especially on warm, calm evenings. Rain or strong winds keep them inside. Use a flashlight with a red filter to avoid disturbing them.

3. How can a beginner identify a bat in flight?

Watch for erratic, fluttering flight patterns – bats don't fly like birds. Their wings are long and narrow, and they often swoop and turn sharply. Listen for a high-pitched chatter if you have a bat detector, otherwise the sound of their wings can be a clue. Look for them near lights where insects gather. Size varies: the big brown bat is about 4-5 inches long, while the little brown bat is smaller. Color ranges from dark brown to reddish.

See our state animal guide for the next step.

4. What are key habitat clues for finding bats?

Look for bat droppings (guano) under roosts – they look like small, dark, crumbly pellets. Stains on walls or around entry holes (from natural oils) also signal a roost. Listen for squeaking from inside tree cavities or attics at dusk. Check for bat houses that have been installed in open areas near water. In summer, maternity colonies gather in warm, protected spots. Learn more about bat behavior at our /animals/bat page.

5. Which bat species are common in Michigan?

Michigan hosts nine bat species. The most common are the big brown bat, little brown bat, and eastern red bat. The big brown bat often roosts in buildings and is resilient to white-nose syndrome. The little brown bat has declined due to disease but still seen in some areas. The eastern red bat roosts in trees and has a distinctive rusty color. Other species include the hoary bat, silver-haired bat, and tri-colored bat. For a full list, visit our /wildlife/michigan page.