Animal Diversity Web

Geographic Range

Vampyrum spectrum lives primarily in northern South America and Central America. Their range extends from central Brazil and Peru to southern Mexico. They are also found on Trinidad in the Antilles. (Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

• Biogeographic Regions
• neotropical

Habitat

They roost in dense, lowland forest below 1,650 m elevation, usually near a river or stream. They are also found in other moist, evergreen forest, yards, secondary growth woodlands, forest edges, and swampy areas. They have been observed roosting in human structures and hollow trees. (Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• rainforest

• Other Habitat Features
• riparian

• Range elevation

  1650 (high) m

  5413.39 (high) ft

Physical Description

Vampyrum spectrum is the largest bat species in the New World. Adults weigh between 145 and 190 g, and have a wingspan of 762-914 mm (some exceed 1 m). Head and body length is 125 to 135 mm, there is no tail. The ears are rounded and large, extending to the nose when laid forward, they measure 39 to 42 mm in length. The noseleaf is also large, 17 mm in length on average. The majority of the body is reddish brown, with a slightly paler underside. The fur is short and and fine. This large bat species is distinguished from other large phyllostomids by their generally larger size, lack of a tail, and by the presence of 4 upper and lower incisors as compared to 4 above and 2 below in the similar species Chrotopterus auritus and Phyllostomus hastatus. The dental formula is 2/2, 1/1, 2/3, 3/3 = 34. (Greenhall, 1968; Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger

• Range mass

  170 to 180 g

  5.99 to 6.34 oz

• Range wingspan

  700 to 900 mm

  27.56 to 35.43 in

Reproduction

These bats form monogamous pairs, possibly for life. (Greenhall, 1968; Vehrencamp, et al., 1977; Nowak, 1999)

• Mating System
• monogamous

The estrous cycle, gestation period, and details of the early growth of young have not been determined for this species. Births have been recorded from May to July but data are scarce. It's possible that births occur at the end of the dry season and beginning of the rainy season in the regions where these bats live. (Greenhall, 1968; Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• viviparous

• Breeding interval

  These bats breed once yearly.

• Breeding season

  The breeding season is unknown.

• Average number of offspring

  1

Both adults assist in the rearing of young. Both parents bring food back to roosts for their young and are solicitous of the young until they reach independence. Males are known to wrap their wings around both mothers and their young while roosting. (Greenhall, 1968; Nowak, 1999)

• Parental Investment
• male parental care
• female parental care

Lifespan/Longevity

In captivity, V. spectrum can live for up to 5.5 years. Their longevity in the wild is unknown. (Greenhall, 1968; Nowak, 1999; Navarro and Wilson, 1982)

• Range lifespan
  Status: captivity

  5.5 (high) years

Behavior

Vampyrum spectrum emerges from roosts at dusk to forage for prey. These bats form nesting groups of up to five individuals in hollow trees, often near a stream or river (though this is based on limited data). The group consists of a breeding pair and two or three of their non-breeding offspring. One adult, usually the female, always stays in the nest with the young. Both parents bring food back to the roost, presumably to share with their young or mates. One radio-tagged male foraged over an area of 3.2 hectares for 1 to 4.5 hours at a time. Their flight has been characterized as slow, maneuverable, and generally close to the ground. Their wing morphology allows them to fly in cluttered spaces and lift off while carrying large prey items. (Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

• Key Behaviors
• flies
• nocturnal
• motile
• sedentary
• social

Communication and Perception

These bats presumably communicate among themselves using the modes of communication widely used in mammals: chemical, auditory, visual, and tactile modes, though this has not been carefully studied in these animals. Males enclose females and their young in their wings while roosting. (Nowak, 1999; Navarro and Wilson, 1982)

These bats use echolocation to help them navigate during flight and prey location. They have been observed using vision to locate prey, which they then capture with a stealthy approach. It has been suggested that they use their sense of smell to locate roosting birds and other prey at night. (Nowak, 1999; Navarro and Wilson, 1982)

• Communication Channels
• visual
• tactile
• acoustic
• chemical

• Perception Channels
• tactile
• echolocation
• chemical

Food Habits

The diet of V. spectrum includes a number of avian, bat, and rodent species. Preferred birds are usually gregarious, or have a very strong odor, and typically roost on branches as opposed to cavities. Prey is apparently located by scent more than by sight or echolocation, and following location it is carefully stalked before a strike is made. These bats begin feeding around dusk, and may have several feeding periods throughout the night. Adults typically feed solitarily, while their mate stays in the nest with the young. Remains of 84 birds of 18 species were found in a single V. spectrum roost. (Vehrencamp, et al., 1977; Nowak, 1999; Navarro and Wilson, 1982)

These bats were previously thought to feed on blood, hence their common name, "False Vampire". It is thought that they may also eat fruit but a mated pair kept in captivity for 5 years refused any fruit offered to them. (Greenhall, 1968; Nowak, 1999; Navarro and Wilson, 1982)

• Primary Diet
• carnivore
  • eats terrestrial vertebrates

• Animal Foods
• birds
• mammals
• insects

Predation

Predation on V. spectrum has not been described, although it is likely that young in roosts can be taken by large, arboreal snakes and other arboreal predators, such as coatis and cat species. They may also be taken by large birds of prey, such as owls and eagles, while in flight.

Ecosystem Roles

Vampyrum spectrum are large, predatory bats which impact their prey communities, especially rodents, birds, and other bats.

Economic Importance for Humans: Positive

The economic importance of V. spectrum to humans is not known.

Economic Importance for Humans: Negative

There are no known adverse affects of V. spectrum on humans.

Conservation Status

Vampyrum spectrum has been designated as 'Lower risk / near threatened' by the IUCN. ("International Union for the Conservation of Nature and Natural Resources", 1996)

• IUCN Red List

  Near Threatened
  More information

• IUCN Red List

  Near Threatened
  More information

Contributors

David Hamman (author), Michigan State University, Barbara Lundrigan (editor), Michigan State University.

References

IUCN Redlist. 1996. "International Union for the Conservation of Nature and Natural Resources" (On-line ). Accessed May 12, 2003 at http://www.redlist.org/.

Engstrom, M., F. Reid. 2003. What's in a Name?. Bats Magazine, 21/1. Accessed 05/24.03 at http://www.batcon.org/batsmag/feature.html.

Greenhall, A. 1968. Notes on the behavior of the false vampire bat. Journal of Mammalogy, 49: 337-340.

Navarro, D., D. Wilson. 1982. Vampyrum spectrum. Mammalian Species, 184: 1-4. Accessed 05/24/03 at http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/default.html.

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

Vehrencamp, S., F. Stiles, J. Bradbury. 1977. Observations on the foraging behavior and avian prey of the neotropical carnivorous bat, Vampyrum spectrum. Journal of Mammalogy, 58: 469-477.