MOUSTACHED BATS: Mormoopidae

PHYSICAL CHARACTERISTICS

Moustached bats are named for their moustache-like distinctive feature. Above their upper lip, they have tufts of stiff hair. Their lips are large, with flaps and folds of skin on the bottom. When their mouth is open it appears to form a funnel. There are three common names for species in this family: moustached bats, ghost-faced bats, and naked-backed bats.

These bats are relatively small to medium size. The size of these bats' forearms range in length from approximately 1.4 inches (3.6 centimeters) to 2.6 inches (6.6 centimeters).

Moustached bats have a small bump on their nose and their eyes are relatively small. All bats in this family have a tail. Ears vary in size and shape but always have a tragus (TRAY-gus), meaning a flap of skin at the bottom of the external ear. In some species, the wings connect to the body at a point high along the middle of the back, making the surface of the back appear naked. These bats are commonly referred to as naked-backed bats. Ghost-faced bats can be easily identified by the folds of skin that reach from ear to ear, across the chin.

The fur of moustached bats can be gray, bright orange, brown, or reddish brown. Within species, individuals can vary widely in color. The fur color of some species in this family may change in different seasons. Fur in this family is short, fine, and thick.

GEOGRAPHIC RANGE

Moustached bats are found from the southern United States, including Arizona and southern Texas, through to Mexico, Central America, and South America to Brazil, and much of the West Indies.

HABITAT

These bats generally live in tropical (hot and humid) habitats below 10,000 feet (3,000 meters). They live in the rainforest, forest, and in open areas. They generally roost in caves, mines, tunnels, and the hollows of trees. Some of these bats have been found in houses.

DIET

Moustached bats feed on a wide range of insects, including flies, beetles, moths, and mosquitoes.

BEHAVIOR AND REPRODUCTION

Moustached bats generally roost together in large colonies. Observations of the Parnell's moustached bats have found approximately 5,000 individuals roosting together.

Moustached bats, like all bats, are nocturnal, meaning they are active at night. At night they emerge to forage for food by using echolocation, the detection of an object by listening to reflected sounds that are called out. They catch their prey (animals hunted for food) while flying. In forested habitats, these bats often search for prey, animals they hunt for food, along trails and roads and fly low, within 3.3 feet (1 meter) of the ground. The wings of these bats are associated with the ability to maneuver, fly rapidly, and remain in the air for long periods of time.

At the beginning of the rainy season, females give birth to a single young each year. Gestation (pregnancy) lasts approximately sixty days.

NEW FAMILY: NEW NAME

Mormoopidae have a complex history of how they became their own family. These bats were first described in the early 1800s. For most of the twentieth century, this group was usually considered a subfamily of the Phyllostomidae, and given the name Chilonycterinae. (Some authorities continue to classify the mormoopids as only a subfamily of Phyllostomidae.) Mormoopidae became accepted as a distinct family and in 1972 was given its own name and family.

MOUSTACHED BATS AND PEOPLE

These bats can eat large numbers of nocturnal insects, including many that are harmful to crops and ones that are considered pests, such as mosquitoes. Humans are causing the loss of population among some species of these bats by destroying their habitat.

CONSERVATION STATUS

The IUCN lists two species as Near Threatened, meaning they are not currently threatened, but could become so. MacLeay's moustached bat is listed as Vulnerable, meaning it faces a high risk of extinction.

PARNELL'S MOUSTACHED BAT (Pteronotus parnellii): SPECIES ACCOUNT

Physical characteristics: Like other bats in this family, Parnell's moustached bat has distinctive stiff hairs around its mouth. The fur color is medium to dark brown. These bats are relatively small with forearms ranging from 2.2 to 2.5 inches (5.5 to 6.3 centimeters). They have wingspan of about 13.4 to 13.8 inches (34 to 35 centimeters).

Geographic range: These bats are found throughout the Greater Antilles, Central America, southern Mexico, northern South America east of the Andes, northern Colombia, Venezuela, Brazil, Peru, and the Guianas.

Habitat: Parnell's moustached bats roost in mines and caves, generally in large chambers and passageways far from the cave entrance. These bats live in habitats ranging from arid to humid, tropical forests.

Diet: Parnell's moustached bats eat insects, primarily beetles and moths.

Behavior and reproduction: Parnell's moustached bats are extremely active. They are most active in the early evening. Observations of these bats in Mexico saw them emerging from their roost shortly after sunset. Some of the bats returned within one and a half hours, but most appeared to remain away from the roost for five to seven hours. The total number of bats in the cavern system was estimated at 400,000 to 800,000 individuals. It was estimated that these bats consumed between 4,190 and 8,380 pounds (1,900 to 3,805 kilograms) of insects each night.

These bats have a body temperature that varies with the environment, called heterothermic (het-ur-oh-THER-mic). When they are feeding, their body temperature remains high. When at rest, their body temperature and heart rate lower, thus conserving energy. When their heart rate slows down to conserve energy, the bats are going into torpor. Protected in their roost, Parnell's moustached bats can go into torpor from several hours to several months. If they go into a long-term torpor during the winter months it is considered hibernation.

These bats catch their prey while flying and can detect insects through dense vegetation. They are the only species of New World (North America, Central America, and South America) bat to have developed specialized echolocation calls. Structures within the ears of these bats work with the nerve cells to allow the bat to hear narrow and specific frequencies. This distinctive call enables the bat to sense the speed things move at, and thus relate its hearing to moving objects.

The only time males and females roost together during the year is when they are mating. Females have one offspring a year after a gestation period of approximately fifty days. Babies have no fur. Most of these bats usually give birth at the start of the rainy season, even though some may mate several months earlier.

Parnell's moustached bats and people: The relatively large bats of this species consume large numbers of insects, many of which are considered pests to humans, such as mosquitoes. One bat is capable of consuming over 1,000 insects per night. Occasional reports have connected these bats with rabies, a viral disease that affects the nervous system and can be deadly. Rabies is usually transmitted by the bite of an infected animal.

Conservation status: The IUCN does not list these bats as threatened. ∎

FOR MORE INFORMATION

Books:

Fenton, M. Brock. Bats. New York: Checkmark Press, 2001.

Fenton, M. Brock. The Bat: Wings in the Night Sky. Buffalo, NY: Firefly Books, 1998.

Ruff, Sue, and Don E. Wilson. Bats. New York: Benchmark Books, 2001.

Schober, Wilfried, and Eckard Grimmberger. The Bats of Europe and North America. Neptune City, NJ: T.F.H. Publications, Inc., 1997.

Periodicals:

Schnitzler, Hans-Ulrich, and Elisabeth K. V. Kalko. "Echolocation by Insect-Eating Bats." Bioscience (July, 2001): 557.

DeBaca, Robert S., and Clyde Jones. "The Ghost-faced Bat, Mormoops megalophylla, (Chiroptera: Mormoopidae) from the Davis Mountains, Texas." The Texas Journal of Science (February, 2002): 89.

Web sites:

Bat Conservation International, Inc. Discover the Secret World of Bats. http://www.batcon.org (accessed on July 5, 2004).

Weinstein, Bret, and Phil Myers. "Family Mormoopidae (Ghost-faced Bats, Moustached Bats, and Naked-backed Bats)." Animal Diversity Web. http://animaldiversity.ummz.umich.edu/site/accounts/information/Mormoopidae.html (accessed on July 5, 2004).