Big brown bats are among the sturdiest and most adaptable bats in the East, and Maine’s records reflect that. The state holds 86 occurrence entries for this species, more than for most of Maine’s other bats, including the eastern small-footed myotis, which shows up in only a handful of reports. That gap says more about how often people notice a big brown bat than about how many actually live here.
A bat that roosts wherever Maine offers shelter
This bat doesn’t need one particular kind of home. Across Maine, that shows up as maternity colonies packed into barn lofts, church steeples, and the attics of old camps around the state’s lakes, alongside natural roosts in hollow trees, loose bark, and rock crevices in the North Woods. Winter sends the colony into old mines, quarry rock, and building wall spaces, anywhere that holds a stable, cool temperature through the cold months.
Hunting over lakes and farmland through midsummer
Records climb through spring and peak sharply in August, matching a season when insects are thickest and young bats have joined the colony’s nightly hunts. Maine’s lakes, farm fields, and forest edges concentrate the beetles and moths this bat favors, and its broad wings and sturdy build let it work those edges rather than open sky. A big brown bat circling the same dock light or porch lamp night after night has found a reliable patch of insects, not a tame relationship with the people nearby.
Status in Maine
NatureServe ranks the big brown bat S4, apparently secure, and it’s native to Maine. The state’s mines, quarries, and undisturbed rock crevices remain important winter shelter, and this bat has fared better against white-nose syndrome than many of Maine’s smaller, cave-hibernating species.




