DESCRIPTION: Wt=5-6g, L=2.4-3.4" (60-86mm) -- the smallest bat in the U.S., and one of the smallest mammals in North America. Pale yellow or gray to reddish-brown above, whitish below. Wings, "tail", and feet blackish, as is the face, ears, nose, giving it a masked appearance.
NATURAL HISTORY: Insectivorous, using echolocation to find its aerial prey. Nocturnal, but seen frequently by people (despite its small size) because it is often one of the first bats out in the late afternoon and one of the last to roost in the early morning. Nonmigratory. Usually solitary, but may form small maternity colonies. Unlike most bats that have only one offspring per year, Western Pipistrelle's have two offspring per litter that usually are born in June. See Bat Facts for more.