Family: Phyllostomidae, New World Fruit Bats view all from this family
Description Usually gray-brown (sometimes dark brown) above; paler below. Surface of interfemoral membrane well furred. No tail. Short, rounded ears; small tragus. Large eyes. Thickened, M-shaped fold of skin over nostrils. Outside lower incisor has 7 fan-shaped lobes (unique among bats); cheek teeth reduced.
Dimensions L 2 1/2-3 3/8" (65-87 mm); HF average 5/8" (18 mm); FA 2-2 1/4" (50-56 mm); Wt 7/8-1 1/2 oz (24-43 g).
Breeding Female bears 1 young, apparently at any time of year.
Habitat Mainly humid forest. Usually roosts in caves, but also in mines and hollow trees.
Range Central Mexico south into South America.
Discussion Discovered in Mexico in the 16th century by the Spanish conquistadores, who named them after the blood-sucking creatures of eastern European legend, vampire bats feed entirely upon blood and occur only in the New World. The vampires are among the few bats that use their wings for walking on the ground. Sleeping by day in caves or other dark, protected places, Hairy-legged Vampire Bats feed at night, chiefly on the blood of birds, such as chickens, turkeys, guinea fowl, ducks, and geese. The bat uses sharp upper incisors to quickly inflict a wound so shallow that the victim rarely notices. It bites chickens on the lower legs or near the cloaca (anal opening), where there are few feathers. Curling the tongue into a tube that fits a V-shaped notch in its lower lip, the feeding bat sips the blood, which flows freely due to an anticoagulant in its saliva. Unless the victim is very small, the amount of blood taken by the bat is not harmful; more serious, after the bat has flown away, is the potential for blood loss owing to slowed clotting, the vulnerability of the open wound to infection, and the possibility of rabies transmission. These large-eyed bats have good vision, but a poorly developed system of echolocation. They usually congregate in small groups of only 1 to 3 per cave, rarely more than 12, though in one cave 35 were found. The carcass of a single Hairy-legged Vampire Bat was found in an abandoned railroad tunnel near Comstock, Val Verde County, Texas, in 1967, but no records have been found in, or even near, the United States since. Biologists believe that vampire bats do not exist in this country.