Townsend's big-eared bat, Corynorhinus townsendii, occurs in western North America, from southwestern Canada to Mexico. Isolated populations of the species also occur in areas of the central and eastern United States. The species occurs state-wide in Utah at elevations below 9,000 feet. Unfortunately, Towsend's big-eared bat populations in Utah are thought to be declining, and the species is therefore included on the Utah Sensitive Species List.
Townsend's big-eared bat can occur in many types of habitat, but the species is often found near forested areas. Caves, mines, and buildings are used for day roosting and winter hibernation. Consequently, human disturbances of caves and the closures of abandoned mines may constitute threats to the species.
Females congregate into nursery colonies and typically give birth to one young each year. Townsend's big-eared bats eat flying insects, particularly moths, and individuals are often seen foraging near trees. The species is nocturnal, and individuals typically do not leave their roosts until well after sunset.