At dusk in summer, small shapes flit over lawns, ponds and streetlights across the central United States. Those are bats, and they are far more varied than most people realize. Knowing a few species helps you understand which ones might use a bat house, which prefer trees and caves, and why so many are in trouble.
Insect eaters
All bats in the central United States eat insects, including moths, beetles and flies. One often-cited 2011 scientific estimate put the value of bats' pest control for American agriculture in the billions of dollars each year. They do not suck blood and do not attack people. Bats forage mostly at night, using echolocation to find prey.
Species you may encounter
| Species | Where | Roost habits | Likely to use bat houses? |
|---|---|---|---|
| Big brown bat | Across the U.S., common in towns and farms | Buildings, bat houses, tree hollows, bridges | Yes, the most common house user in many areas |
| Little brown bat | Northern Plains, Midwest, East | Buildings, attics, bat houses; hibernates in caves | Yes, but populations have crashed in many regions |
| Evening bat | Southern Plains, Midwest | Tree hollows, buildings, bat houses | Sometimes |
| Eastern red bat | Eastern and central states | Hangs from tree foliage | Rarely |
| Hoary bat | Widespread, migratory | Roosts in trees | Rarely |
| Silver-haired bat | Across northern states and the Plains | Tree bark and hollows | Occasionally |
| Tricolored bat | Eastern half of the U.S. | Caves in winter, trees and sometimes buildings in summer | Sometimes |
| Mexican free-tailed bat | Texas, Oklahoma, the Southwest | Caves, bridges, large buildings | In some places |
| Northern long-eared bat | Eastern and central states | Trees and caves | Rarely |
Ranges and habits change, so check your state wildlife agency or a regional field guide for species in your county.
Who is rare or protected
Several bat species in the central and eastern United States are federally listed as endangered or threatened, including the Indiana bat, gray bat and northern long-eared bat. Others are under review. That is why you should never harass, trap or close roosts that may hold protected species without advice from a wildlife professional. The status of species changes, so check the U.S. Fish and Wildlife Service and your state wildlife agency.
Threats
- White-nose syndrome. A fungal disease that affects hibernating bats and has killed millions of bats in North America since it was first documented in the mid-2000s. Some species have declined sharply.
- Wind energy. Migratory tree-roosting bats, such as hoary, eastern red and silver-haired bats, are killed in significant numbers at wind turbines.
- Habitat loss. Fewer large trees, cave disturbance and building changes reduce roosts.
- Pesticides and fewer insects. Fewer insects mean less food.
- Direct persecution. Fear and misunderstanding cause needless killing.
How bats spend the year
In spring, females return to maternity roosts, which can be in attics, barns, bat houses or tree hollows. They have one or two pups, depending on the species, in early to midsummer. Young bats cannot fly for several weeks, so disturbing a roost in summer can leave pups to die. By late summer the pups fly, and in fall bats mate and either migrate or move to caves, mines or buildings to hibernate. Species such as red, hoary and silver-haired bats migrate long distances. Others hibernate nearby.
Rabies and health
Bats can carry rabies, but most do not, and bats are not more dangerous than other wildlife if left alone. The key rule is never to handle a bat with bare hands. If a bat bites or scratches someone, or you wake to find a bat in a room, call your local health department or doctor right away, because bat bites can be tiny and hard to see. If possible, keep the bat contained, without touching it, for testing, and follow health department advice. Pets should be up to date on rabies vaccinations.
Bats in your building
If bats are living in your attic, do not seal them in. Many states restrict exclusion during the pup season, because blocking exits can trap flightless young. Contact a licensed wildlife professional or your state wildlife agency for advice on safe exclusion times and methods. Offering a bat house nearby, installed in advance, can give excluded bats an alternative roost.
How to help
- Put up a bat house following our placement guide.
- Keep dead trees (snags) where it is safe to do so.
- Reduce pesticide use and plant native flowers that support moths and other insects.
- Provide water.
- Reduce outdoor lighting at night where possible.
- Leave cave and mine roosts alone. Visiting hibernation sites can wake bats and cost them energy.
- Spread accurate information. A bat is a neighbor, not a monster.
Frequently asked questions
Which bats will use a bat house?
Big brown bats and little brown bats are the most common users in the central United States. Others sometimes do.
Are bats blind?
No. Bats can see, and many use echolocation to hunt in the dark.
Do bats attack people?
No. They avoid people. The risk comes from touching a sick or injured bat.
What causes white-nose syndrome?
A fungus that grows on hibernating bats, disrupts their hibernation and has killed millions in North America.
What should I do if I find a bat in my house?
Do not touch it. Contact your health department, especially if anyone might have been bitten, and call a wildlife professional for removal.
