North Cascades

Threatened and Endangered Species

Pacific Western "Townsend's" Big-Eared Bat Corynorhinus townsendii townsendii The Pacific Western "Townsend's" big-eared bat is approximately 4 inches in length with a wing span of 10-10-1/2 inches, and has, as its name implies, large ears. The fur color of the bat varies, but most often is a slate gray tipped with brown. Adult Townsend's bats weigh between 0.25 and 0.50 ounce! Bats are mammals; they are warm-blooded. Females give birth to live offspring, and subsequently, the young are nourished with their mother's milk. The Townsend's bat is nocturnal and uses its large ears and sensitive echo location to capture and feast on moths, beetles, and flies at night. It lives at elevations ranging from sea level to 3,500 feet and is dependent on cliffs, caves, and old mines for roosting, nursery, and hibernation sites. The bats are highly sensitive to disturbance by people who explore caves or other curious humans and will abandon their roost if repeatedly disturbed.