Photo Credit: Rachel Shively

Brazilian free-tailed bat

Tadarida brasiliensis

Order: Chiroptera

Suborder: Yangochiroptera

Family: Mollosidae

Call characteristics:

High frequency caller (~25 kHz range)

Body Length

3 - 4 in

(7.9 – 9.8 cm)


  1/4 - 1/5 oz

(7 - 12 g)

Brazilian free-tailed bats are named for the long tails that extend beyond their uropatagium (membrane surrounding the tail). Like other species of the family Molossidae, Brazilian free-tailed bats have distinctive large, rounded ears that form a semicircle around the face and nearly meet on the forehead. They are a fast flying bat and have been clocked at speeds up to 60 mph. This species is know for its extremely large colonies;  the largest, Bracken Cave, is home to more than 15 million individuals. Brazilian free-tailed bats commonly roost in caves, bridges, and buildings. They are generalist feeders, preying on moths, beetles, flies, and insects in the order Hemiptera. Females typically give birth to a single pup each summer. The average lifespan of Brazilian free-tailed bats is 8 years.

Conservation Status

Canada Species at Risk

Photo Credit: Jordi Segers




NABat utilizes monitoring data provided by a broad network of partners to support regional and range-wide inferences about changes in the distributions and abundances of bat populations facing current and emerging threats.

Information used to populate this page was obtained from the following sources:


NatureServe Explorer

United States Fish and Wildlife Service Environmental Conservation Online System 

Bat Conservation International Bat Profiles

National Atlas of the United States. (2011). North American Bat Ranges, 1830-2008. National Atlas of the United States. Available at:

Taylor, M. 2019. Bats: an illustrated guide to all species. Washington, DC: Smithsonian Books.