| These little bats often have twins, which are usually born in late May. If the female breeds again the same summer, she gives birth to a single baby the second time. Males are known to maintain harems during the breeding season. The male marks the females in his harem, and the harem site, with his chin.
Argentinian Brown Bats have been found in both deciduous forests and forests where most of the trees are green year-round. Most are recorded from fairly low elevations of 500 meters or less. They roost in buildings, hollow trees, and caves. Small numbers of bats roost together behind shutters or in other hiding places in buildings, but an enormous number of them - perhaps 100,000 - were found in a cave in Mexico. They are active soon after sunset, and are sometimes caught in mist nets near the entrances of caves or over water.
Head and Body: 48-64 mm; Tail: 29-43 mm
d'Orbigny, A.D., 1847. Zoology Atlas. In Voyage dans l'Amerique meridionale (le Brazil,la Republique Argentine ...Chili, Peru, &c.) pendant 1826 - 1833, 4:13.
Mammal Species of the World
Mammalian Species, American Society of Mammalogists' species account