Vampire bats are not as fearsome as they are pictured in films nor do they possess any such false standing in real life apart from the fact that it feeds on blood. True vampire bats live in the tropical and subtropical America where they drink fresh blood of birds and mammals and not of humans. Vampires’ bite is likely to cause rabies in victim which can be fatal to both humans and cattle.
Vampire Bat Facts
Anatomy
- Vampire bats are 14 – 18 inches (37 – 45 cm) long with the adult bats weighs up to 15 – 50 grams.
- They do not possess tail and their fur is colored in different shades of brown.
- The bats have short conical muzzle while the ears are small.
- The snout has naked pads along with U-shaped grooves at the tip.
- Vampires do not have a nose leaf.
- There are thermosensory organs in the vampire bats grooves with the help of which they are able to sense heat that releases from the prey.
- They have well developed upper teeth which are not only large but also have razor edges. Bats with their sharp teeth open a small wound and drink blood. The bats’ stomach is also adapted for blood feeding.
- The common vampire can also walk on its well-developed thumb and powerful hind legs.
(Photo by B. G. Thomson/Photo Researchers, Inc)
Three Vampire Species
There are three vampire bat species: the common vampire bat (Desmodus rotundus) is perhaps the most widespread of the three species as is distinguished by its long thumb, pointed ears, and naked interfemoral membrane. The bat has 20 teeth and is found in the northern Mexico south to central Chile, and Uruguay and central Argentina. It is probably one of the most common mammals in eastern Mexico.
The white-winged vampire (Diaemus youngi) is relatively less common. Unlike common vampire, the white-winged bat has a short thumb and 22 teeth. The bat lives in the tropical habitats of Venezuela, Peru, Brazil, to as far as South America and Guiana. The isolated population is also found in Trinidad and in Mexico.
The hairy-legged vampire bat (Diphylla ecaudata) is the third vampire. It is comparatively smaller of the other two species. The bat is distinguished by its short rounded ears and softer fur. The thumb is also far too short. It has 26 fan-shaped teeth. The vampire lives in the Central America and southern Mexico and Brazil.
Habitat
- During daytime the vampire bats typically roost in hollow trees, caves, old wells, rock crevices, old buildings and mines. A single colony of common vampire may be as large as consisting of 2,000 bats but the average number is 100.
- They fancy living in dark places.
- Both male and female roost together and they also share their habitat with other species.
- Vampire bats are swift walkers and they are adept to move on thumb and feet.
- During night the vampires come out of the cave with a soundless flight.
- They fly as low as 3 feet (90 cm) above the ground and the flight is slow.
Feeding Diet and Ecology
- Vampires mostly attack when their prey is asleep. They make a shallow bite on a hairless part of the body. While they bite bats do not disturb the victim and because they cut away a very small piece of skin, the prey remains asleep even when it is wounded.
- One of the reasons why the victim could not feel even when bat sits on it is vampires rest on their thumbs instead of claws, as do other bats. They never make their presence feel to the victim. Humans are also unlikely to be awakened by vampires’ bite.
- Prominent among the species is the common vampire which drinks so much blood in one go that it can hardly fly few minutes after it is done.
- The common vampire bats are known to feed on blood of large mammals including cattle and horses. They also feed on human blood but only sometimes.
- The vampires are most likely to take blood either from the neck or from legs in case of animals but when it comes to humans they attack on big toe. Therefore if you’re living in vampire bats habitat you better keep your nose open all the time!
- The white-winged bat consumes blood from birds. They rarely feed on mammals’ blood.
- The hairy-legged vampire often drinks blood of birds such as chicken but it also attacks mammals.
- Vampire bats are also bred in captivity but in here they are fed with defibrinated blood which does not contain any clotting agents. One of the vampires is known to live as long as 13 years in captivity in a laboratory in Panama.
- Unlike bats species vampires find their prey with the help of a thermosensory ability and acute smelling sense. Like other bats they also use echolocation to detect the precise direction of the prey.
- Thanks to the fact that their prey is not only large but often immovable. Vampires do not seem to have the kind of difficulty which others (Old World Bats) come across. The Old World Bats must go out and search for the fast-moving insects, which indeed is quite tough.
- Vampires occasionally attack dogs probably because dogs also have strong hearing sense. Dogs can detect higher sound frequencies of bats.
Reproductive Biology
- The biologists have not been able to observe the breeding habits of the white-winged and hairy legged vampire bats. As for the common vampire bat, it gives birth to a single young on an average though twins are also expected.
- The gestation period lasts 210 days.
- The vampire bats are known to breed all year round giving rise to a possibility that there might be more than one birth each year.
- The mother will not look after the young in fact they would be left in the cave while she would search for food.
References
Churchill, S. Australian Bats. Sydney: Reed New Holland, 1998.
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.
Kingdon, J. Mammals of East Africa: An Atlas of Evolution, Volume 2b. New York: Academic Press, 1974.
Nowak, R. M. Walker’s Mammals of the World, Vol. 1. Baltimore: Johns Hopkins University Press, 1999.
Leave a Reply