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).

In this instance, less energy is required to catch a few large insects than hundreds of tiny moths or gnats. Other bats use their feet to snatch insects from the surface of ponds and lakes. With the ...