Social life of vampire bats: feasting on fresh blood with friends
The name “vampire bats” conjures up many feelings and images in people, one of the fear and blood creatures of the night resembling Dracula, but surprisingly friendship and cooperation are among the qualities unknown to these unique inhabitants of the night.
Scientists on Thursday provided a deeper understanding of the social relationships between vampire bats, showing how those who have forged “friendships”-like bonds with others will meet these friends while seeking a meal.
Researchers attached small devices to 50 vampire bats to track nighttime foraging in Panama, when these flying mammals drink blood from wounds they inflict on cattle in the pastures. The study involved female bats, known to have stronger social relationships than males.
Among the bats were 23 wild-born individuals who had been held in captivity for about two years during related research into the social behavior of bats. Social links had already been observed between some of them. After being released into the wild, bats often reunited with a “friend” while foraging, possibly coordinating the hunt.
“Each bat maintains its own network of close cooperative social bonds,” said behavioral ecologist Gerald Carter of Ohio State University and the Smithsonian Tropical Research Institute, who led the research published in the journal PLoS Biology.
Social bonds between vampire bats when roosting in trees include grooming and regurgitating blood meals for hungry friends. The study showed that the social bonds formed in the dormitories extended into the hunt.
“This study opens an exciting new window into the social lives of these animals,” Carter said.
Researchers suspect that bats, although they hardly ever go foraging with their “friends”, connect with them while hunting – perhaps even by recognizing the vocalizations of others – for mutual benefit. . They hypothesize that bats could exchange information about the location of prey or access to an open wound for food.
Vampire bats, which inhabit warmer parts of Latin America and have a wingspan of around 18 centimeters (7 inches), are the only mammals that have a blood-only diet. They reside in colonies ranging from tens to thousands of individuals.
“People’s first reaction to vampire bats is usually, ‘Uh, scary. But once you tell them about their complex social lives, they’re pretty surprised that we can find such behavior that looks somewhat like what humans do – and you might expect in primates – in primates. bats, ”said study co-author Simon Ripperger. , post-doctoral researcher at the Smithsonian Tropical Research Institute.
Ripperger called them “amazing creatures” for several reasons.
“Even outside of their social life, vampire bats are quite special: specializing in a 100% blood diet is already quite rare in vertebrates,” said Ripperger.
“They are amazing runners, you wouldn’t expect in a bat. They have heat sensors in their snouts that help them find a place to take a bite. They have a protein in their saliva that prevents the blood to clot, which is actually used in medical trials to help prevent blood clots in patients who have had a stroke. “
Bats attack their prey from the ground, using their sharp teeth to open a wound, lapping up blood with their tongues.
Carter said there was reason to fear vampire bats, as they can transmit rabies to livestock and humans.
“But I think they’re beautiful and interesting animals in their own right,” Carter added.
“In that way, they’re a bit like grizzly bears, sharks, rats, and poisonous snakes: animals that might not help people in any way and even endanger them, but still should. be appreciated for themselves. “