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.
- 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.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- rainforest
- Other Habitat Features
- riparian
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.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
These bats form monogamous pairs, possibly for life.
- 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.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
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.
- 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.
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.
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.
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.
- 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.
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.
- 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.
Additional Links
Contributors
David Hamman (author), Michigan State University, Barbara Lundrigan (editor), Michigan State University.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- monogamous
-
Having one mate at a time.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- tactile
-
uses touch to communicate
- echolocation
-
The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.
- chemical
-
uses smells or other chemicals to communicate
- carnivore
-
an animal that mainly eats meat
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
References
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.
IUCN Redlist. 1996. "International Union for the Conservation of Nature and Natural Resources" (On-line ). Accessed May 12, 2003 at http://www.redlist.org/ .