The Vampires That Feed on Vampires

Bats of many species, including the common vampire bat, play host to blood-sucking parasites.
PHOTOGRAPH BY JOEL SARTORE, NATIONAL GEOGRAPHIC CREATIVE

• The Vampires That Feed on Vampires

If vampire bats and blood-drinking moths are scary, meet their parasites.

“Blood-feeding is a lifestyle which has evolved independently in many groups of animals,” says Tommy Leung, a parasitologist at the University of New England in Australia. Called hematophagy, eating blood is common, he notes, and “found in over fourteen thousand living animal species, even in groups that most people might not have suspected.”

Only three out of the nearly 1,400 known bat species are vampires. But did you know that even these species are preyed upon by blood-suckers?

Many bat species must contend with tiny, blood-feeding bat flies that can look like the face-huggers out of the Alien movies. Species of vampire bats, however, may have it worse than most.

“Vampire bats have more parasites than the average bat,” says Gerald Carter, a bat biologist and postdoctoral researcher at the Smithsonian Tropical Research Institute in Panama.

Researchers in one study captured hundreds of specimens from 53 bat species to assess their prevalence of parasites. They found that two vampire bat species had some of the heaviest loads of bat flies. One particularly unfortunate common vampire bat was covered with 63 blood-sucking bat flies.