Leptonycteris yerbabuenae
lesser long-nosed bat

Arid and semi-arid regions of Mexico and southwestern United States, including the Sonoran Desert. (Ceballos et al., November 1997)

Leptonycteris yerbabuenae is found near cacti, usually living in caves in huge groups. The habitat ranges from desert scrub in the southwestern United States and northern Mexico to high elevations on wooded mountains further south in Mexico.

Leptonycteris yerbabuenaee is a yellow-brown or cinnamon gray bat, with a total head and body measurement of approximately 3 inches (7.62 cm). The tongue measures approximately the same length as the body. This species also has a small noseleaf. The wingspan of Leptonycteris yerbabuenae is approximately 10 inches (25 cm) and the mass is roughly 23 g. (Snyder and Tyler, 1997; Southwest Center Species Database and October 15, 1997)

Lesser long-nosed bats exhibit many characteristic behaviors, including gregarious roosting, no cooperative/social bonding, unexpected sleeping patterns, and local and long distance migration along nectar trails/corridors (Fleming et al. 1998).

Lesser long-nosed bats spend over half of their lives in a dayroost, leaving only to forage at night. They spend most of their time in the dayroost resting, digesting food, interacting with other individuals, mating and caring for young. Individuals of this species form extremely large colonies, including tens of thousands to over one hundred thousand animals, in caves which trap metabolic heat. This metabolic heat reduces the energetic cost to females and increases growth rates in the young. In these colonies, the adults are fairly passive; there is a low frequency of interactions among females, and between females and their young. The most frequent behavior is nosing other individuals. This species is non-cooperative; they do not exhibit socially cooperative behavior like allogrooming, and females have only been seen to nurse their own young (Fleming et al. 1998).

Although lesser long-nosed bats rest during the day and do not actively move or fly, this chiropteran is usually fully awake and alert. For reasons yet unknown, this species sleeps much less than is predicted by its body size and metabolic rate (Fleming et al. 1998).

Members of this species also tend to migrate along a nectar trail or corridor, following the availability of food resources. This behavior is exhibited especially in the northern region of the bat's range, where resources are not available year-round. The females also migrate when they converge on maternity colonies near the end of their pregnancies (Rojas-Martinez et al. 1999). (Fleming, Nelson, and Dalton, February 1998; Rojas-Martinez et al., 1999)

The diet of lesser long-nosed bats consists of nectar and pollen from the night-blooming flowers of the Agavaceae, Bombaceae, Cactaceae, Convolvulaceae and Leguminosae. They also feed on the pulp of cactus fruit. They are not obligate cactus visitors. The diet is influenced by availability of possible food resources (Ceballos et al. 1997).

Lesser long-nosed bats forage at night, between 24:00 and 02:00, when flowers have accumulated substantial amounts of nectar. These bats begin by taking generally long commuting flights to a foraging area. Once they arrive at the foraging area (which usually consists of about one square kilometer), they survey many plants. Later, they may make return visits to several of those plants to feed (Horner et al. 1998).

This species has a very close relationship with the cacti on which it feeds. Since lesser long-nosed bats are nectarivores with a relatively large foraging area, feeding results in both short and long distance pollen movements. By doing so, these bats help to create gene flow within and between populations of columnar cacti (Horner et al. 1998).

Through fecal analysis, it has been shown that this species also disperses the seeds of fruit on which it feeds (Rojas-Martinez et al. 1999).

Lesser long-nosed bats help to pollinate agave, from which tequila is made (Arita and Wilson, 1987). (Arita and Wilson, December 1987)

Leptonycteris yerbabuenae is considered an endangered species in North America. Destruction of its primary food resources and general habitat by the tequila industry and agriculture is threatening its population numbers. This species is also especially vulnerable to extinction because it is a specialist, feeding on the nectar, pollen and fruit of several plant families present in southern North America and Central America. It is also especially susceptible because of its migratory habits. Conservation efforts should include food resources, roosting sites and protection of habitats along the migratory route (Arita and Santos-Del-Prado, 1999). (Arita and Santos-Del-Prado, February 1999)

Leptonycteris yerbabuenae was previously known as a subspecies: L. curasoae yerbabuenae. In older literature, this species has sometimes been referred to as L. sanborni.