Vampire bats don’t suck blood, they simply use their few razor sharp teeth to pierce the skin and then use their tongue to lap up the blood so they can drink it.
How Do Vampire Bats Drink Blood?
Vampire bats don’t suck blood with their teeth; they use their teeth to pierce an animal’s skin and then lap up the blood with their tongue. Their saliva prevents the blood from clotting while they drink. Vampire bats can feed up to 30 minutes. While their preferred meal is cow’s blood, vampire bats have been known to feed on human blood.A short from NatGeoWild on vampire bats.
FACT: Vampire bats are the only mammals to survive entirely on blood.