Photo Credit: Merlin D. Tuttle, Bat Conservation International
SCIENTIFIC NAME: Perimyotis subflavus
OTHER NAMES: brown bat, little brown bat, pipistrelle, pip.
DESCRIPTION. The eastern pipistrelle bat is one of the smallest North American bats. It varies in length from 2.8 - 3.74 inches and weighs between 0.2-0.3 ounces. The wingspan is eight to ten inches. The dorsal fur is tricolored when parted – each hair having a dark base, a lighter middle, and a yellow-brown tip. Forearms are pinkish to flesh-colored. The tragus (external ear covering) is generally oval or rounded, distinguishing it from the sharp tragus of Myotis bats.
DISTRIBUTION. Eastern pipistrelle bats occur in eastern Canada, most of the eastern United States and southward through eastern Mexico to Central America. Pipistrelle bats are very common throughout Alabama.
HABITAT. Pipistrelle bats occupy a wider variety of habitats than perhaps any other bat in Alabama. They may be found hibernating in caves, mines and rock crevices during winter. Almost any cave of some size is likely to contain pipistrelle bats during winter months. During summer, they are found in smaller numbers in caves and also roost in hollow trees, under tree bark, in brush piles and to a limited extent in buildings. They may use artificial roosting boxes (bat houses) during the summer. Pipistrelles are solitary bats and when found roosting are usually found singly, though rarely two to three may cluster together.
LIFE HISTORY AND ECOLOGY. Pipistrelles roost and sleep during the day and are active at night. They are insectivorous, eating a wide variety of insects including moths, beetles, mosquitoes, night midges, flies, and ants. They are slow flyers and forage over waterways and around forest edges. Insects may be caught in the wing or tail membrane during flight, and eaten “on the wing.” Mating occurs in the fall. The female will store the sperm during the winter and fertilization takes place in the spring. One or two young are born hairless and pink in late spring and cannot fly for about a month. For the first few days after birth, the female will carry the young while she forages. Pips hibernate during the winter, though in south Alabama they may forage year-round when the weather is warm and insects are present.
As with most wild mammals, pipistrelles can and do contract and transmit rabies. Though the incidence of rabies in pips is very low, any bat that appears sick or cannot fly should be avoided. The eastern pipistrelle is a very beneficial species and - like all Alabama bats - are a natural means of insect control.
CONSERVATION STATUS. This species is classified as Lowest Conservation Concern.
AUTHOR: M. Keith Hudson, Wildlife Biologist, Alabama Division of Wildlife and Freshwater Fisheries, January 2007