The Brazilian free-tailed bat, Tadarida brasiliensis, occurs throughout southern North America, Central America, and South America. Members of the species roost colonially in caves and buildings, with colonies in some areas containing thousands, or even millions, of individuals. In Utah, few appropriate roosting sites exist, and colonies are much smaller, rarely containing more than a few hundred individuals.
Brazilian free-tailed bats eat insects, primarily moths. Because insects are their major prey item, pesticide use constitutes a major threat to the species. In North America, the species mates in early spring, and females give birth to one young three months later, in June or July. Brazilian free-tailed bats are nocturnal, leaving their roost sites to forage at night. Utah's Brazilian free-tailed bats are migratory, spending their summers in Utah, and their winters in the southwestern United States or Mexico.