Bats of Massachusetts

Conservation of Bats in Massachusetts

Across North America, DDT and other pesticides had a huge effect on bats from the 1940s through the 1960s. Since the ban of DDT in 1972, the population of bats has been slowly recovering. The last hibernating colony of Indiana Bats in Massachusetts was in a mine in the town of Chester in 1939. As their population slowly increased in New York and they returned to Vermont, there was hope that this species would soon be re-discovered in Massachusetts, as well. 

A Little Brown Bat (Endangered) in a cave. Photo by Bill Byrne, MassWildlife

However, these hopes diminished when White-nose Syndrome (WNS) was discovered in a New York cave in 2006. The fungus that causes WNS spread rapidly across much of the United States, and the numbers of bat species that hibernate in caves and mines crashed. As a result of WNS, the Indiana Bat did not return to Massachusetts, and all four bat species that spend winters in caves or mines were listed as Endangered in Massachusetts in 2012. This includes the Little Brown Bat, Northern Long-eared Bat, Eastern Small-footed Bat, and Tricolored Bat. The Little Brown Bat was once the most abundant bat species in Massachusetts, but its population declined by more than 99% after the onset of WNS. 

All five of the most important bat hibernacula are now closed to public access to protect the few surviving bats from disturbance. MassWildlife acquired two of the mines and installed gates to protect the bats. These gates are specially designed to allow the bats to freely fly through while keeping people out. Research is underway to better understand the fungus that causes WNS, but currently there is no way to prevent or effectively treat it.

Massachusetts Bat Species

There are 9 species of bats that live in Massachusetts, 5 of which are listed under MESA as Endangered and 3 others that are listed under MESA as species of Special Concern.  

List updated August 2024

Common Name	Scientific Name	Status	Range	Summer Habitat	Winter Habitat
Big brown bat	Eptesicus fuscus	Common	statewide	buildings, trees	buildings, caves, mines
Little brown bat	Myotis lucifugus	MA: E	statewide	buildings	caves, mines
Northern long-eared bat	Myotis septentrionalis	MA: E Fed: E	statewide	trees, building exteriors (rarely inside buildings)	caves, mines
Indiana bat	Myotis sodalis	MA: E Fed: E	Berkshire & Hampden counties (last record 1939)	caves, mines, hollow trees, under tree bark	caves, mines
Eastern small-footed bat	Myotis leibii	MA: E	Berkshire & Hampden counties	under tree bark; in rock talus & deep fissures	caves, mines
Tricolored bat	Perimyotis subflavus	MA: E	statewide	trees (rarely in buildings)	caves, mines, rock crevices
Silver-haired bat	Lasionycteris noctivagans	MA: SC	probably statewide	trees, rock crevices	buildings, trees (migratory)
Eastern red bat	Lasiurus borealis	MA: SC	statewide	tree foliage	migratory
Hoary bat	Lasiurus cinereus	MA: SC	statewide	tree foliage	migratory

How you can help bats

• Educate yourself and others about bats by learning about the variety of threats they are facing in Massachusetts and across the country.
• Help provide safe, warm roosting sites for females to raise their young. Create a bat-friendly backyard by leaving old, dead, or dying trees standing to provide natural roost sites. Or, if you’re handy, learn how to build and install a bat house.
• Support bats and other rare species in Massachusetts by donating to MassWildlife’s Natural Heritage and Endangered Species Program.
• If you must exclude or evict bats from your home, ensure the process is safe and humane by following MassWildlife’s recommendations found in the Massachusetts Homeowner's Guide to Bats.
• Be a citizen scientist. If there is a colony of 10 or more bats on your property, use our online form to report it. Colonies may be found in trees, buildings, attics, barns, sheds, or other outbuildings. This information will be used to help conserve the state’s endangered population of little brown bats.