The lesser long-nosed bat, Leptonycteris curasoae yerbabuenae, is a nectar-, pollen-, and fruit-eating bat that migrates seasonally from Mexico to southern Arizona and southwestern New Mexico. Primarily associated with dry habitats in Mexico and southwestern U.S., this bat pollinates flowers of species of columnar cacti and paniculate agaves and disperses seeds of columnar cacti species throughout its range. Surveys in Arizona and Mexico conducted in the mid-1970’s through 1985 revealed low numbers of this bat in known roosts. This information led to the species being declared federally endangered by the U.S. Fish and Wildlife Service in 1988. NO critical habitat was proposed or designated for this species.
The lesser long-nosed bat is a medium-sized bat weighing 20-25 grams as an adult. Adult fur color is grayish to reddish-brown; juveniles have gray fur. Its elongated rostrum bears a small, triangular noseleaf, its ears are relatively small and simple in structure and it has a minute tail.
Two sets of resources, suitable day roosts and suitable concentrations of food plants, are critical for the lesser long-nosed bat. Caves and mines are used as day roosts and these bats will often fly 10-15 miles each night to foraging areas. Like many other bats, this species uses night roosts for digesting their meals. These roosts include the bats’ day roosts as well as other caves, mines, rock crevices, trees and shrubs, and occasionally abandoned buildings. Lesser long-nosed bats appear to be sensitive to human disturbance; a single brief visit is sufficient to cause a high proportion of them to temporarily abandon their roost and move to another.