Diaemus youngiwhite-winged vampire bat

Geographic Range

Diaemus youngi has been recorded in throughout tropical South America, including parts of Paraguayan Chaco, Venezuela, Costa Rica, Mexico, Belize, Bolivia, Argentina, Brazil, and Trinidad. However, little work has been done on this rare species, therefore the range may be larger than what has been documented. (Greenhall, et al., 1983)


Diaemus youngi has been found in moist tropical and dry forests. They have been found roosting in caves, tree hollows, and on the edges of banana tree plantations. (Nowak, 1997; Elizondo, 1999)

Physical Description

Head and body length of white-winged vampire bats is about 85 mm, there is no external tail. The forearm length is approximately 50-56 mm. Adults weigh approximately 30-45 grams. The pelage is usually a shiny clay color, light brown, or dark cinnamon brown. The edges of the wings are white, and the membrane between the second and third fingers is largely white. They have a peculiar short thumb with a single pad under the metacarpal. The slightly re-curved lower incisors with their unique system of cusps distinguish this genus from Desmodus. Diaemus youngi is the only bat known to have 22 permanent teeth. The other two vampire bat species (Desmodus rotundus and Diphylla ecaudata) lack the second upper molar and only have 20. (Nowak, 1997)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    35 to 45 g
    1.23 to 1.59 oz
  • Average length
    85 mm
    3.35 in


The mating system has not been documented in this species. However, related species are polygynous.

Little is known about reproduction in this species. However, the common vampire bat, Desmodus rotundus, breeds throughout the year, bearing a single young after an 8-9 month gestation. (Greenhall, et al., 1983; Lord, 1992)

  • Average number of offspring

Little information exists for this speceis. However, in related species young are nursed and cared for by females for several months after birth, at which time the young become independent. Young bats are typically born naked and helpless and develop rapidly in the weeks following their birth.


The lifespan of Diaemus youngi has only been documented in captivity where they can live 20 years. The relate common vampire bat (Desmodus rotundus) lives around 9 years in the wild. (Marlett , 2001)

  • Average lifespan
    Status: captivity
    >20 years
  • Typical lifespan
    Status: captivity
    20 (high) years


White-winged vampire bats have not been observed locomoting on the ground in the wild. However, they are morphologically similar to common vampire bats (Desmodus rotundus), suggesting that they may be capable of walking on the ground. To feed, these bats select their prey, then cautiously moves across a branch until they are close enough to extract blood from the prey’s feet. An incision is made after preliminary licks have been made on one of the digits, and blood is extracted by further licking the wound. Anticoagulants from the bat’s saliva ensure that blood flows freely. If the prey is startled or moves, the bat will hide under the branch until it can move back to the feeding site. Feeding time lasts around 15 minutes, then the bat flies away.

White-winged vampire bats are nocturnal and roost in small groups. (Schutt, et al., 1999)

Communication and Perception

There is no documented research on communication was found for this species. However, all microchiropterans utilize echolocation for navigation and possibly spatial organization. In addition, most bats use audible vocalizations, smells, and touch for communicating among individuals. In addition bats use vision, smell, touch, and auditory signals for perceiving their environment.

Food Habits

White-winged vampire bats feed mostly on blood from various bird species, including free-ranging poultry species (chickens, Guinea fowl, and turkeys). (Nowak, 1997; Schutt, et al., 1999)

  • Animal Foods
  • blood


Although little is known about predation on this species, it is likely that most predation occurs on young in roosts by small predators, such as snakes, and by birds of prey on bats leaving roosts. (Tuttle, 1996)

  • Known Predators

Ecosystem Roles

There is insufficient information on Diaemus youngi and its potential role in the ecosystem. It is possible that this species harbors and transmits diseases to various birds. They impact bird populations through parasitism, by feeding on their blood. (Nowak, 1997; Schutt, et al., 1999)

Species Used as Host
  • Various bird species

Economic Importance for Humans: Positive

There is no information available on economic importance of this species.

Economic Importance for Humans: Negative

Diaemus youngi is considered a pest because individuals sometimes feed on the blood of domestic poultry species. They may also be a carrier of rabies and other infectious diseases. (Elizondo, 1999)

Conservation Status

This species is not protected under CITES or IUCN. The status of populations is poorly known. (Greenhall, et al., 1983)


Andrew McLain (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.



living in the southern part of the New World. In other words, Central and South America.

World Map


uses sound to communicate


young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

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.


an animal that mainly eats meat

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal


uses smells or other chemicals to communicate


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.


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.

female parental care

parental care is carried out by females


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).


having the capacity to move from one place to another.


active during the night


an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death


having more than one female as a mate at one time


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.


an animal that mainly eats blood

scrub forest

scrub forests develop in areas that experience dry seasons.


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


uses sight to communicate


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year


Elizondo, L. 1999. "Diaemus youngi" (On-line ). Accessed 11/05/2002 at http://translate.google.com/translate?hl=en&sl=es&u=http://www.inbio.ac.cr/bims/ubi/mamiferos/ubiespejo/ubiid%3D1571%26-find.html&prev=/search%3Fq%3Ddiaemus%2Byoungi%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8.

Greenhall, A., G. Joermann, U. Schmidt, M. Seidel. 1983. Mammalian Species: Desmodus rotundus. American Society of Mammalogists, 202: 1-6.

Lord, R. 1992. Seasonal reproduction of vampire bats and its relation to seasonality of bovine rabies. Journal of Wildlife Diseases, 28 (2): 292-294.

Marlett , J. 2001. "Vampire Bat" (On-line ). Accessed 11/23/02 at http://www.scz.org/animals/b/vampire.html.

Miller, G. 1907. The families and genera of bats. Bull. U.S. Natl. Mus, 57: i-xvii + 1-282.

Nowak, R. 1997. "White-winged Vampire Bat" (On-line ). Accessed 11/05/02 at http://www.press.jhu.edu/books/walker/chiroptera.phyllostomidae.diaemus.html.

Schutt, W., F. Muradali, N. Mondol, K. Joseph, K. Brockmann. 1999. Behavior and Maintenance of Captive White-Winged Vampire Bats, Diaemus youngi. Journal of Mammalogy, 80 (1): 71-81.

Tuttle, M. 1996. Protection from Predators. Bat Conservation International, Inc, 4 (2) /Fall: 5-6. Accessed (Date Unknown) at http://www.batcon.org/bhresearcher/bv4n2-6.html.