This species feeds at night primarily on moths and immobile diurnal insects such as butterflies and katydids, which it locates by vision, even at low ambient light levels. It uses warm diurnal roosts in caves, mines, and buildings. Depending on the season, the bats roost singly or in groups of up to several hundred individuals, hanging separately from the ceiling rather than clustering. Females congregate in large maternity colonies of about 100 to 200 individuals in the spring and summer, utilizing different mines or different areas within mines from those occupied in the winter. A few males are found in these colonies, although large male-only roosts also form. The single young is born between mid-May and early July, following a gestation of almost nine months (Wilson and Ruff 1999).

This species is known from north Sinaloa and southwest Chihuahua (Mexico) north to south Nevada and south California (USA), also including Baja California (Mexico) (Simmons 2005).

It is found in several protected areas, such as Sierra del Pinacate Reserve and Vizcaino protected area. For several caves identified as significant roosts (for hundreds of individuals) or maternity colonies, gating mines can be an important action.