Bats of Wisconsin: Six Native Species

Wisconsin hosts six bat species, all insectivorous and ecologically vital for pest control and pollination.

Species List

1. Little Brown Bat (Myotis lucifugus): Most common; caves/mines in winter, buildings/trees in summer. Threatened by White-nose Syndrome.
2. Big Brown Bat (Eptesicus fuscus): Larger, more cold-tolerant; often roosts in buildings year-round.
3. Northern Long-eared Bat (Myotis septentrionalis): Forest-dwelling; federally threatened (White-nose Syndrome).
4. Silver-haired Bat (Lasionycteris noctivagans): Migratory; tree-roosting; solitary.
5. Eastern Red Bat (Lasiurus borealis): Migratory; foliage-roosting; distinctive red fur.
6. Hoary Bat (Lasiurus cinereus): Largest WI bat; migratory; frosted fur; tree-roosting.

Conservation Status

• White-nose Syndrome (WNS): Fungal disease decimating cave-hibernating species (Little Brown, Northern Long-eared) since 2014 in WI.
• Legal protection: All bats protected under WI Statute 29.604; endangered/threatened species have additional safeguards.

Benefits

A single bat eats 600–1,000 mosquito-sized insects/hour. Wisconsin's bats save agriculture millions in pest control annually.