Habitat: The big brown bat is the most common bat in Pennsylvania. They are commonly found in a various habitats such as attics, barns, behind doors and shutters, and hollow trees. They can live either in the city or country.

Appearance: The fur is a dark brown color while the face, ears, and flight membranes are black.

Size: The brown bat is about 4.1 to 4.8 inches long and the average weight ranges between 0.42 to 0.56 ounces. Their wing span ranges from 12.1 to 12.9 inches. 

Activity: The big brown bat starts to fly around at dusk. When they fly they give off an audible chatter. Their primary diet consists of beetles and true bugs such as junebugs, stinkbugs and leafhoppers. Big brown bats seek out caves, building, mines, and storm sewers to hibernate for the winter. They usually start of hibernate around October through December and emerge in March and April.

Life Cycle: The female big brown bat have young in June and usually have two babies per liter. As they mature, they leave the nursery colony and the adult male take up residences. They can live up to nineteen years in the wild.

PA Game Commission . (n.d.). Bats Wildlife Note. Pennsylvania Game Commission. https://www.pgc.pa.gov/Education/WildlifeNotesIndex/Pages/Bats.aspx.