The big brown bat is the Adirondack’s largest bat; only the hoary bat is larger. The long, lustrous fur is brown. The ears, wing and tail membranes are black. Total length is 105-123 mm (4.1-4.8 in).

Estimates say as many as a million bats may hibernate inside the Millie Mine shaft. Here's when you can see them take flight.

Here's what to know about the bats and mine. The big brown bat is found in virtually every American habitat ranging from timberline meadows to lowland deserts, though this species is most abundant ...