Moustached Bats (Mormoopidae)

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Moustached bats

(Mormoopidae)

Class Mammalia

Order Chiroptera

Suborder Microchiroptera

Family Mormoopidae

Thumbnail description
The lips of moustached bats are ornamented with flaps and folds of skin surrounded by bristle-like hairs giving the appearance of a moustache

Size
Moustached bat are small to medium in size with forearms ranging from 1.4 to 2.6 in (3.5–6.5 cm) in length and weighing 0.2–0.9 oz (6–26 g)

Number of genera, species
2 genera; 8 species

Habitat
Moustached bats are found in lowland Neotropical areas below 10,000 ft (3,000 meters) from rainforest to forest and in more open, arid areas

Conservation status
Vulnerable: 1 species; Lower Risk/Near Threatened: 2 species

Distribution
Central America and parts of South America

Evolution and systematics

Moustached bats belong to the Noctilionoidea superfamily with the bulldog bats (Noctilionidae) and American leaf-nosed bats (Phyllostomidae). Mormoopids are not known as other than recent fossils.

Physical characteristics

Generally small in size with body weight not exceeding 0.9 oz (26 g), moustached bats have flaps and folds of skin around the mouth as well as moustache-like hairs making them distinctive. There are three distinct forms of moustached bats. Ghost-faced bats, species of the genus Mormoops, have very well developed flaps of skin around the mouth. In the skulls of ghost-faced bats, the braincase protrudes over the rostrum. In other moustached bats, the flaps of skin are not so well developed and the braincase does not protrude over the rostrum. Among these moustached bats, the wings either join at the side of the body (sooty moustached bat [Pteronotus quadridens], Wagner's moustached bat [Pteronotus personatus], Parnell's moustached bat [Pteronotus parnellii], MacLeay's moustached bats [Pteronotus macleayii]) or at mid-back (Davy's naked-backed bat [Pteronotus davyi], big naked-backed bat [Pteronotus gymnonotus]). The significance of the expression "naked backs," a species in the genus Dobsonia (family Pteropodidae), remains unknown. The fur of moustached bats can be gray or bright orange in color.

Distribution

Moustached bats occur in the West Indies, Central America, and in South America ranging into Brazil and Peru.

Habitat

Moustached bats occur in lowland Neotropical areas from rainforest to forest and in more open, arid areas.

Behavior

Moustached bats typically roost together in large colonies, in hollows such as caves, mines, or tunnels, and probably also in hollow trees. Roosting individuals may or may not be in physical contact with one another. Aerial-feeding species that

eat flying insects, moustached bats use echolocation to detect, track, and evaluate their targets. When echolocating, seven species of mormoopids separate pulse and echo in time. But Parnell's moustached bat separates pulse and echo in the frequency domain, making them more like the horseshoe (Rhinolophidae) and Old World leaf-nosed bats (Hipposideridae) of the Old World.

Feeding ecology and diet

Moustached bats, like all mormoopids, are exclusively insect eaters. They eat a wide range of flying insects, from flies to beetles and moths. In forested areas, these bats typically hunt along trails and roads sometimes flying very close to within 3.3 ft (1 m) the ground and vegetation.

Reproductive biology

Females bear a single young each year at the beginning of the rainy season. Gestation appears to last about 60 days, and in the West Indies copulations occur in January and February.

Conservation status

The IUCN considers two species (Antillean ghost-faced bat [Mormoops blainvillii] and sooty moustached bat [Pteronotus quadridens]) as Lower Risk/Near Threatened. MacLeay's moustached bat is considered Vulnerable because of its declining habitat.

Significance to humans

As all bats, mormoopids pollinate numerous plants, including economically important crops such as banana, mango, and avocado. In the tropics, bats are responsible for 70–95% of all seeds dispersed, thus playing an important role in forest regeneration.

Species accounts

List of Species

Parnell's moustached bat
Ghost-faced bat

Parnell's moustached bat

Pteronotus parnellii

taxonomy

Phyllodia parnellii (Gray, 1843), Jamaica. Nine subspecies are currently recognized, four occurring in the West Indies.

other common names

Spanish: Murcielago bigotudo.

physical characteristics

Smaller, medium-sized bats with forearms ranging from 2.2 to 2.5 in (5.5–6.3 cm), and weighing 0.4–0.9 oz (12–26 g).

distribution

Found throughout the Greater Antilles, and in the mainland of Central America from southern Sonora and Tamaulipas, the south of Mexico to northern South America east of the Andes. They also occur in northern Colombia, Venezuela, the Guianas, Brazil, and Peru.

habitat

These bats occur in habitats ranging from arid to humid, tropical forest.

behavior

Roost in hollows, usually in caves or abandoned mines. Colonies can consist of hundreds of individuals. Their presence in areas without caves indicates that they also roost in hollows in trees. When bats are active, they are extremely active, to an extent that they require to spend much time sleeping. They are also strongly heterothermic, meaning that their body temperature is highly variable. They can reach and maintain body temperatiures appropriate to their physiological and behavioral needs, thus conserving energy. When they are actively feeding, metabolic activity and body temperature are high. When they are resting, both metabolism and temperature are low. This process of resting under lowered metabolic activity and body temperature is called torpor. And they may enter torpor for a few hours or several months. The intensity of torpor ranges from shallow to deep. Deep, long-term torpor occurring in winder is termed hibernation. Bats spend their periods of torpor in a roost, where they can hang protected from dangers.

feeding ecology and diet

These bats hunt flying insects that they detect by Doppler-shifted echoes, separating pulse and echo in frequency. Their echolocation calls are dominated by one frequency, usually around 60 kHz. The bats eat mainly beetles and moths. In forested areas, they often can be observed hunting along trails and roads. Their distinctive echolocation calls makes them easy to recognize with a bat detector tuned to about 60 kHz. In flight, the production of echolocation calls is synchronized to the wingbeat and partly driven by movements of the viscera against the diaphram. Contractions of muscles in the middle ear contribute to the bats' avoiding deafening themselves during production of echolocation signals. Acoustic information acquired during echolocation is represented in the cerebral cortex.

reproductive biology

Females bear a single young annually after a gestation period of about 50 days. The young are naked and helpless at birth. The timing of reproduction varies across the species' range, with births usually peaking around the start of the rainy season. For example, if mating occurs in autumn, the sperm is typically stored by females throughout hibernation, sometimes up to seven months, in the uterus. Within a few days of leaving their winter shelter, females ovulate one egg, and sperm are released. Fertilization and implantation then take place shortly afterwards. Typically, females of a population form a maternity colony at a site different than the hibernation site where breeding occurred. Gestation usually lasts from 40 to 50 days and results in a single offspring, usually in the late spring. Birth is a rather uneasy process: hanging inverted, mothers grab the newborn as it emerges from the birth canal and the newborn in turn grabs the abdominal fur of the mother with its hind feet, pulling to facilitate its own birth. Infants usually begin nursing almost immediately after birth. Some reports are indicative of females helping others with the birth of young. Healthy species in the wild live from five to ten years. Probably polygynous.

conservation status

Classified as Lower Risk/Least Concern by the IUCN.

significance to humans

These bats have occasionally been reported with rabies. Insectivorous bats such as mormoopids eat large quantities of insects, including those that are harmful to crops and humans. For example, a 0.5 oz (13 g) individual could easily consume more than 1,000 insects, including mosquitoes, on an average night.

Ghost-faced bat

Mormoops megalophylla

taxonomy

Mormoops megalophylla (Peters, 1864), Coahuila, Mexico. Four subspecies are currently recognized.

other common names

Spanish: Murcielago de labios festoneados.

physical characteristics

These bats have a peculiar upturned nosed and extensive flaps of skin around the mouth. Smaller medium-sized bats, ghost-faced bats have forearms 2.0–2.2 in (5.1–5.7 cm) long. They weigh from 0.4 to 0.7 oz (12–19 g). They are larger than Antillean ghost-faced bats, the other species in the genus.

distribution

Found from southwestern Texas and Arizona southwards through Baja California, Mexico, Honduras and El Salvador. There is a second population in South America, the northern parts of Colombia and Venezuela, the Dutch Antilles and Trinidad, and another along the Pacific coasts of Colombia, Ecuador and northern Peru.

habitat

Occur in humid through semi-arid and arid regions from tropical forests to riparian forests and arid coastal regions. Ghost-faced bats roost in hollows, typically in caves and abandoned mines.

behavior

Strong, fast fliers that forage over water, land, and in forests. Males and females may roost in different parts of the same cave or mine. Roosting individuals usually not in physical contact with one another. Colonies of ghost-faced bats can number thousands of individuals which tend to emerge together in streams.

feeding ecology and diet

They eat flying insects, including moths, beetles and flies, reflecting on the availability of prey where they forage. Ghost-faced bats eat flying insects, taking a wide range of prey according to what is available where they forage.

reproductive biology

Females bear a single young each year, with the timing of birth reflecting local rainy seasons. This species is most likely polygynous.

conservation status

Not listed by the IUCN.

significance to humans

These bats are subject to cyclical outbreaks of rabies that cause mass mortality.

Common name / Scientific name / Other common names	Physical characteristics	Habitat and behavior	Distribution	Diet	Conservation status
Antillean ghost-faced bat Mormoops blainvillii	Light brown upperparts, buffy underparts. In dark phase, upperparts are dark brown, underparts are ochraceous tawny. Lower lip has fleshy peg-like projections. Tail is well developed. Head and body length 2–2.9 in (5–7.3 cm), tail length 0.7–1.2 in (1.8–3.1 cm), forearm length 1.8–2.4 in (4.5–6.1 cm), average adult weight 0.4–0.6 oz (12–18g).	Variety of habitats from desert scrub to tropical forest. Extremely swift flight, movement of wings makes humming sound. Dwells deeper in caves than any other Jamaican bat.	Greater Antilles and adjacent small islands.	Most likely consists mainly of insects.	Lower Risk/Near Threatened
Davy's naked-backed bat Pteronotus davyi	Delicate, naked bat. Wings joined on back. Coat color is usually coffee, sometimes orange. Head and body length 1.6–2.2 in (4.2–5.5 cm), tail length 0.7–1 in (1.8–2.5 cm), forearm length 1.7–1.9 (4.3–4.9 cm), weight 0.17–0.35 oz (5–10 g).	Dry territories of the province of Guanacaste, and the environs of Quepos to the northern Caribbean slope from sea level to 1,310 ft (400 m). Take refuge in caverns with high temperatures. Nocturnal.	Northwestern Peru and northern Venezuela to southern Baja California, southern Sonora, and Nuevo Leon, Mexico; Trinidad; and southern Lesser Antilles.	Mainly insects.	Not threatened
Big naked-backed bat Pteronotus gymnonotus	Naked back, wings united on mean line, hindquarters are naked with a very small coat. Coat color is orange coffee. Head and body length 2.1–2.7 in (5.5–6.9 cm), tail length 0.8–1.1 in (2.1–2.8 cm), forearm length 2–2.2 in (5–5.5 cm), weight 0.38–0.63 oz (11–18 g).	Low territories of the Caribbean and Pacific slopes, from sea level to 4,920 ft (1,500 m). Refuge is usually caverns. Gregarious and nocturnal.	Southern Veracruz, Mexico, to Peru, northeastern Brazil, and Guyana.	Insects caught in the air.	Not threatened
Macleay's moustached bat Pteronotus macleayii	Skin folds are on chin and lower lip. Brownish in color. Hindquarters are naked with a small coat. Average weight 0.14–0.21 oz (4–6 g), wingspan 9.8–11 in (25–28 cm).	Large chambers and passageways far from the cave entrance. Roost in large colonies.	Habana and Guanabacoa, Cuba.	Mainly insects.	Vulnerable
Wagner's moustached bat Pteronotus personatus	Coat color is orange or coffee, both equally common. Head and body length 1.7–2.2 in (4.3–5.5 cm), tail length 0.6–0.8 in (1.5–2 cm), forearm length 1.6–1.9 in (4.2–4.8 cm).	Dry and humid low territories of the Pacific slope, from sea level to 1,310 ft (400 m). Roost in large colonies. Nocturnal.	Colombia, Peru, Brazil, and Suriname to southern Sonora and southern Tamaulipas, Mexico; and Trinidad.	Insects.	Not threatened
Sooty moustached bat Pteronotus quadridens	Coloration is variable, oftentimes light or dark brown, grayish brown, or ochraceous orange. Underparts are usually paler. Head and body length 1.5–3 in (4–7.7 cm), tail length 0.6–1.2 in (1.5–3 cm), forearm length 1.4–2.6 in (3.5–6.5 cm).	Roost in caves and tunnels, as well as houses. May also shelter in hollows of plants. Seek darker recesses when in caves. Generally hang singly rather than in compact masses.	Cuba, Jamaica, Hispaniola, and Puerto Rico.	Mainly insects.	Lower Risk/Near Threatened

Resources

Books

Hutson, A. M., S. P. Mickelburgh, and P. A. Racey. Global Status Survey and Conservation Action Plan, Microchiropteran bats. Gland, Switzerland: IUCN SSC Chiroptera Specialist Group, 2001.

Nowak, R. M. Walker's Mammals of the World. Vol. 1. Baltimore: Johns Hopkins University Press, 1999.

Reid, F. A. A Field Guide to the Mammals of Central America and Southeast Mexico. New York: Oxford University Press, 1997.