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Bats: Despite their man-made reputation, bats are among humans' best friends.

 October 22, 2001

Vampire bats really do exist! However, there are only three species of vampire bats out of the roughly 950 bat species in the world, located in Central and South America. It was the vampire bat on which early Europeans based the connections between bats and vampires, indelibly etched into the public mindset and world culture in 1897 by Bram Stoker when his novel Dracula was published.

Here are two recordings of large bat colonies. Click PLAY listen.
Where would Halloween be without those blood-sucking, winged creatures that vampires can turn into whenever necessary?

Bats have long been associated with vampires and other supernatural beings, a connection that Bram Stoker's classic novel Dracula forever cemented in the public psyche in the late nineteenth century. But the legends of bats' associations with vampires and ghoulish beings far preceded the famous author.

Spanish conquistadors first saw vampire bats when they came to Central and South America in the 1500s, and noticed how their feeding off the blood of other animals was similar to the vampires of their own legends. Over time, these stories became so strongly associated with the legend of vampires that the bat and the vampire became virtually synonymous with each other.

This is really a bad rap on bats! It has become very clear in modern times that bats are not those evil beasts of the dark underworld that feed off of the blood of humans. Frankly, bats are quite fascinating and very gentle creatures that are among the most beneficial animal species on Earth. Believe it or not, bats play a crucial role in the health and survival of rainforests!

Bats are mammals with wings, and they are the only mammals that can fly. Despite their reputation, bats are among the most beneficial animals in the world.

Bats are mammals with wings, and they are the only mammals that fly. (Their scientific name, the order Chiroptera, means |winged hand.2) They are warm-blooded animals with fur, give live birth, and nurse their young. There are about 900 to 1,000 species of bats located in almost all but the coldest climates of the world, and all of them are at risk because their value to man and the environment are not understood. Of this number, there are only three known species of vampire bats. Nearly half of the bat species native to the United States are endangered.

Bats are major factors in controlling insect populations, pollinating plants and distributing seeds necessary in perpetuating the circle of life in ecosystems. In fact, there are some plants, such as the African Baobab Tree (oddly enough, known as the upside down tree) and the Australian Ironwood, that are solely dependent on bats for spreading their seeds and for pollination. Unfortunately, their love for insect delicacies has contributed to the decline of many bat species due to poisons used by farmers and ranchers to control insects. Yet, bats can help farmers by not just eating harmful insects, but worms and other bugs which can damage crops. For instance, a colony of just 150 big brown bats can eat up to 18 million or more rootworms each summer (Source: Bats4kids).

The world's largest bat cave is Bracken Cave in Central Texas, summer home to more than 25 million Brazilian Free-tailed bats. Bats live in most regions of the world except in extreme cold climates. (Photo Courtesy: Capital Area Master Naturalist)

Bats have lived on the planet for over 50 million years, longer than many other mammals. They generally live naturally to 30 years of age, but many are killed by natural predators and man before then. Very adaptable, bats live in caves and buildings, under bridges, in trees and many other places. And they either migrate or hibernate, depending on the species, with some bats migrating over 3,000 miles round trip!

Bat Phenomenon in Texas

The Congress Avenue Bridge in Austin, Texas, is home to the largest urban population of bats in North America, but it almost didn't happen. When the bridge was built in 1980, thousands of the area's indigenous bats began moving in under the bridge and quickly became a national phenomenon. This set off alarms with the local citizenry who moved to eradicate the animals for fear they would attack humans or spread disease. Bat Conservation International came in and eased Austin's fears by educating them about the gentle nature and benefits of bats and that bats would not bother them as long as people did not try to handle them.

Even though many bats have excellent eyesight, many bats can also "see� with sound, called echolocation. This helps them "see� their way better in the dark and help locate their meals of insects and bugs.

Click PLAY to listen:

Today, this colony of bats numbers over 1.5 million, and creates truly one of the most alluring tourist attractions in North America as they rise up and fly out from under the bridge each day at dusk. They will eat about 20-30,000 pounds of insects each night, including many bugs harmful to local crops. These Mexican free-tail bats do migrate to and from Central Mexico, arriving in Austin and other parts of the southwestern US each spring.

Bats may live in caves, such as these Kansas gray myotis bats, but many live in buildings, under bridges, in trees and other places suitable for their nocturnal lifestyle. (Photo: University of Kansas)

The positive impact bats have had on ecosystems worldwide is immeasurable, but their role in the web of life is clear. Their legend is intriguing and will remain a staple of Halloween and the folklore of the preternatural world. In fact, you really can't picture Halloween, Dracula, Nosferatu or the real world without them!

-- Eric McLamb

 

 

Did you know ...?

  • Bats are not blind. They have excellent night vision and many, such as fruit bats, use their sense of smell and sight to find their meals of flowering plants and fruits

  • Some bats use echolocation as a means of "seeing" in the dark using sound and sonar, very much the same way dolphins and Beluga whales use sound to "see� underwater.

  • Bats hang upside down in their caves, trees or other dwellings because they are not good walkers. They are the only mammals that fly and thus have never made much use for standing or walking.

  • Bat droppings (guano) support entire ecosystems of unique organisms, including bacteria useful in detoxifying wastes, improving detergents and producing gasohol and antibiotics. (Source: Desert USA)

  • Bats range from very small to very large flying mammals. The world's smallest one is the Bumblebee Bat, with a wingspan of six inches. The largest bat is the Flying Fox, with a wingspan of up to seven feet!

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