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  Chiroptera · Vespertilionidae · Corynorhinus townsendii

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Corynorhinus townsendii

Townsend's Big-eared Bat

Order: Chiroptera
Family: Vespertilionidae

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Credit: New Mexico Bat Call Library, W. L. Gannon
Image of Corynorhinus townsendii
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Conservation Status: Least Concern.

Sporting prominent ears that look almost like wings, Townsend’s big-eared bat largely preys on moths over open pasture and forest canopy. For females, foraging increases during pregnancy and lactation, from one or two foraging bouts per night to three, and the distance traveled also increases, from 1.0 km to more than 4.0 km per night. Females form maternity groups in the spring, in caves and shelters, where they give birth to a single pup. In addition to winter hibernation, these bats also experience daily periods of torpor during cooler weather, a sleeplike state of reduced motor and metabolic activity. Townsend’s big-eared bat occurs in the western United States, northward to British Columbia, as far east as the Rocky Mountain States from Idaho to Texas, including Kansas and Oklahoma, and there are also populations in Arkansas, Missouri, Kentucky, Virginia, and West Virginia.

Also known as:

Western Long-eared Bat, Western Big-eared Bat, Western Lump-nosed Bat, Mule-eared Bat

Sexual Dimorphism:

Females are larger than males.


Range: 89-116 mm


Range: 9-12 g


Cooper, 1837.  Annals of Lyceum of Natural History of New York, 4:73.


Mammal Species of the World (opens in a new window).

Distribution of Corynorhinus townsendii

Image of Corynorhinus townsendii
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Image of Corynorhinus townsendii
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Image of Corynorhinus townsendii
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