I’m sure we all have our own idea about vampire bats. The projection of vampires in general in the media range from the old school, coffin dwelling, garlic hating, morphing into a bat type, to the sparkly, vampire “light” type (Twilight Saga), to the burst into flames in the sun, stake me and I turn to goo type (True Blood). All of these have heightened senses of some sort, be it smell, sight, etc. The closest of these projections to real vampire bat feeding behavior, as far as I know, is that of True Blood (which will be explained later). Hopefully this will shed a little light, on the truth about the Vampire Bat.
– Scientific Classification –
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Chiroptera
- Family: Phyllostomidae
- Subfamily: Desmodontinae
- Genus/Species: Desmodus rotundus (Common vampire bat), Diphylla ecaudata(Hairy-legged vampire bat), Diaemus youngi (White-winged vampire bat)
:: The majority of the information will be about the Common Vampire Bat. ::
These interesting looking bats are pretty small, weighing about 15 to 50 grams. And they aren’t just a set of fangs! They have 20 teeth, but they mainly use their super sharp, front incisors to assist in their hematophagous diet (blood as a food source). They are very smart, among the most intelligent of bats, as they must remember a map of where they’ve found a food source in the past. They range from Northern Mexico to Chile, Argentina and Uruguay where they roost in caves. They may live up to 12 years and have an oddly long gestation period of 90-120 days for being such a small mammal.
Normally, these bats feed on quadripedial (4 legged) animals such as cattle, pigs, horses, burros and tapirs. They have the intriguing ability to walk on the ground which gives them a tactic not to wake the animal on which they intend to feed. Doing so may result in death for the inexperienced bat. After landing, they use their leaf shaped nose to sniff out where the blood is closest to the surface of the body.
“When a bite site is chosen the bat carefully licks the skin in order to soften it and flatten down any hairs in the way, all the while keeping several special hairs of their own known as vibrise that grow from the bat’s chin in contact with the animal so as to detect any slight vibration of it’s skin, that might hint of it’s waking. A tiny fold of skin is held in the bats mouth for but an instant. Then at the precise moment of the bite (done with only the very front incisors) the bat takes a short jump backwards, so as to be in a favorable position to flee should the need arise” (The Vampire Bat). From a shallow groove on the top of the bat’s tongue flows an anticoagulant to aid in the flow of the blood. The effects of the anticoagulant can last a while, leading to blood trails down the animal. Obviously this may worry the animal’s keeper which can lead to hatred of the bats and fear of the spread of disease.
Vampire Bat metabolism is so fast that it could starve in less than 48 hours. It cannot use any other food source and its stomach is zig zagged to increase holding capacity. Since blood is very high in water, these bats must have very efficient kidneys. While still feeding, they begin to urinate. Post feeding, the little bats are so bloated they can barely fly.
Here’s a short video featuring some vampire bats feeding on a pig:
And a demonstration of their movement:
- Vampire bat rabies death prompts warning from health officials (cbsnews.com)
- First U.S. Death by Vampire Bat: Should We Worry? (livescience.com)