The Vampires That Feed on Vampires

The Vampires That Feed on Vampires
If vampire bats and blood-drinking moths are scary, meet their parasites.

Bats of many species, including the common vampire bat, play host to blood-sucking parasites.

Another Halloween is upon us, and that means stories about animals that poke you full of holes and eat your insides!But this year, instead of looking upon these vampires in revulsion, perhaps we can find a little common ground. Even our most-hated blood-suckers are plagued by creatures that thirst for blood.

“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.

Vampires on Vampires

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.

And these flies can be relentless.

In Belize, one of Carter’s colleagues studied the bats and their flies by marking both with tiny drops of paint. She released one bat with a marked fly and kept seeing the same fly return to her throughout the night, each time on a different, unmarked bat.

“Apparently, the released bat went back to the roost and the fly switched hosts,” says Carter.

Still not feeling bad for vampire bats? Imagine what it’s like having one or more of these little monsters crawling all over your body.

Beaks Built for Blood

An animal you probably don’t associate with Halloween is the finch—but maybe you should. One species native to Wolf Island in the Galapagos is known for its habit of pecking into the skin of larger birds and then lapping up the blood that pours out.

It’s known as the vampire finch or sharp-beaked ground-finch.

While the finch’s bloodletting looks positively grisly, this behavior is thought to help the birds survive times of extreme drought.

Of course, even vampire finches probably suffer a little bloodsucking of their own. That’s because birds are a favorite meal for mosquitoes.

Vampire Hunters

Mosquitoes are surely one of the least pitiable creatures on earth. Not only do their bites make us itch, but these ubiquitous insects carry a host of diseases responsible for millions of deaths worldwide each year.

But even mosquitoes are not immune to a little blood loss.

Tiny insects called midges have been documented feeding on at least nineteen species of mosquito. Similar to the mosquitoes it parasitizes, the midge has sharp mouthparts called a proboscis. The midge uses its proboscis to stab into a mosquito’s engorged stomach and suck out recently ingested blood. In some cases, this can cause organ damage in the mosquito.

What’s more, scientists have found a species of jumping spider, Evarcha culicivora, that actively targets mosquitoes with a full belly.