Bats

Bats

Bats are misunderstood animals. Because they are nocturnal or active at night, people think of them as spooky and dangerous. Bats are actually fascinating animals that are very helpful to humans. In some cultures, bats are symbols of good luck.

Bats are flying mammals that are found in most parts of the world. Many eat insects but some eat fruit and even frogs and fish.

Bats are flying mammals that are found in most parts of the world. Many eat insects but some eat fruit and even frogs and fish.

©M.Durham/GLOBIO.org
The bone structure of bat wings looks a lot like a hand with very long fingers. Hold out your hand with your fingers spread apart. Can you see the similarity?

The bone structure of bat wings looks a lot like a hand with very long fingers. Hold out your hand with your fingers spread apart. Can you see the similarity?

©M.Durham/GLOBIO.org

Bats are the only mammals that can truly fly. Although some bat species look like mice, bats are not closely related to rodents. Bats have their own scientific group name, which comes from Greek words meaning “hand-wing.” Look closely at the bat wing in the photo to see why the name fits.

Bats are Everywhere

There are more than 1,100 known species of bats. That means nearly one out of four mammal species is a bat! There are two main types, microbats and megabats. Scientists think microbats and megabats may have evolved from the same gliding, shrew-like ancestor.

Microbats are small. Most of them eat insects. They live almost everywhere except the polar ice caps of the Arctic and Antarctic, the hottest deserts and some islands.

Megabats are larger. They eat fruit. In fact, megabats are commonly called fruit bats. They are found only in tropical regions of Africa, Southeast Asia, India, the Pacific islands, and Australia.

Soft Skin and Hearing Aids

Like all mammals, bats have fur-covered bodies. Their wings are a double layer of skin stretched over their arms and long fingers. People think of a bat’s skin as tough and leathery, but it’s really soft. (To find out how soft, touch your eyelid.)

Some microbats have strange “nose leaves” and projections on their lips. They use these features to help them focus sounds as they echolocate. Microbats have small eyes and large ears that are an adaptation for excellent hearing. Fruit bats lack these features because most do not echolocate. They have large eyes and short, rounded ears. Some fruit bats have faces that resemble foxes or dogs. That’s why the largest fruit bats are called “flying foxes.”

Is that a Bat or a Bumblebee?

Fruit bats like the one in this picture are sometimes called flying foxes. Can you see why? This bat’s thin face and big eyes make it look like a tiny fox with wings.

Fruit bats like the one in this picture are sometimes called flying foxes. Can you see why? This bat’s thin face and big eyes make it look like a tiny fox with wings.

©Thomas Hawk

The smallest bat is the endangered Kitti’s hog-nosed bat from Thailand, also known as the “bumblebee bat.” This tiny bat weighs only 2 g and has a wingspan of 16 cm. It’s the smallest mammal on Earth! The large fruit bat from Malaysia weighs about 1.5 kg and has a wing span of nearly 2 m. Life spans of bats are variable, but the little brown bat is known to live more than 30 years.

Where Do Bats Hang Out?

Large groups of bats hanging out together are called camps. These fruit bats hang around all day eating their favorite food, fruit.

Large groups of bats hanging out together are called camps. These fruit bats hang around all day eating their favorite food, fruit.

©G.Ellis/GLOBIO.org

Microbats may roost alone in hollow trees or live with many other bats in caves, mines, and old buildings. Several million Mexican free-tailed bats live in the same colony! Large groups of fruit bats gather to sleep in roosting trees. Females and their young group together, while males may gather in separate groups. Large groups are called “camps.”

Reproduction and Babies

Baby bats are tiny, hairless versions of their parents. Can you see the baby bat in this picture? Try turning your head upside down for a bat-like view.

Baby bats are tiny, hairless versions of their parents. Can you see the baby bat in this picture? Try turning your head upside down for a bat-like view.

©G.Ellis/GLOBIO.org

In some bat species one male mates with many female bats. To attract mates, bats may vocalize, flap their wings, and groom each other. After a two-month gestation, most microbat species give birth to one pup. These babies can weigh up to one-third as much as their mother. Some microbats form nursery colonies where mothers drop off their babies when they fly out to feed. When they return, mothers find their own baby using scent and sounds.

Fruit bats have one pup, following a gestation of four to five months. Pups are weaned from their mothers’ milk at 10-11 weeks. They are then old enough to begin flying and looking for food.

Bat Habits and Survival Secrets

Bats are active at night, when the temperature is cooler and the humidity higher. This helps them save energy and prevent water loss. The darkness also helps them avoid predators such as certain kinds of hawks, snakes and toads. During the day bats lick their fur and comb it with their feet to keep clean. They also groom their wings, using oil from their glands to keep wings soft and in great flying condition.

When it’s hot, bats cool down by licking their fur and wings, then fanning themselves. When it’s cool, they warm up by wrapping their wings around themselves. Microbats and fruit bats are active year round in tropical areas, where fruit and insects to eat are available all year. Some microbats in colder places migrate to where it’s warm. Others stay where they are and hibernate. When hibernating, a bat’s heart rate slows and its body temperature drops in a state called torpor.

Bring on the Bugs!

Some bats eat pollen and are important to the life cycle of plants. This bat looks like it spent the night dipping its head into lots of flowers.

Some bats eat pollen and are important to the life cycle of plants. This bat looks like it spent the night dipping its head into lots of flowers.

©C.Ziegler/GLOBIO.org

Microbats are the world’s most important predators of night-flying insects. Little brown bats can eat 1,200 insects an hour! But some microbats are meat-eaters. They feed on fish, frogs, lizards, rodents, birds, or other bats. Some small microbats eat fruit such as figs. Some eat nectar and pollen from plants.

Do Bats Drink Blood?

Vampire bats are a type of microbat. Yes, they do feed on the blood of birds or mammals. But they don’t turn into Count Dracula. And there aren’t very many of them. Of all the species of bats in the world only three are vampire bats. These are found only in South and Central America. These tiny bats (with a wingspan of 75 mm) don’t suck blood. Instead, they make a cut with their sharp teeth and lap blood. An anticoagulant in their saliva keeps the blood flowing.

Vampire bats do drink blood but they do not suck it from an animal. Instead, they make a tiny cut and lap up the blood that drips out.

Vampire bats do drink blood but they do not suck it from an animal. Instead, they make a tiny cut and lap up the blood that drips out.

©J.Clare/npl/Minden Pictures

Bats as Planters

This hungry fruit bat is taking its lunch to go. Maybe the seeds from this meal will become a new tree that will make even more food for bats.

This hungry fruit bat is taking its lunch to go. Maybe the seeds from this meal will become a new tree that will make even more food for bats.

©C.Ziegler/GLOBIO.org

Bats keep new plants growing by spreading seeds. A fruit bat frequently carries fruit far from its tree, then chews and crushes the fruit against the roof of its mouth. The bat swallows the juice and soft pulp and spits out the tough parts. The fruit’s whole seeds pass quickly through the bat’s digestive system and are dropped with the animal’s poop. This disperses the seeds far and wide. The seeds then germinate and a new plant grows.

Bats as Pollinators

Nectar-feeding fruit bats take in protein-rich pollen as they sip the sugary liquid.

Pollen sticks to the bat’s slender nose as it probes deeply into the flower. The bat transfers the pollen to the next plant it visits. This allows the plant to reproduce. The flowers of bat-pollinated plants bloom at night. Their flowers are large, creamy-white and easy for bats to find in the dark. They may send out strong, bat-attracting odors.

Many plants that need bats to pollinate them are light, bright colors so they can be easily found in the dark. Some even give off special bat attracting odors.

Many plants that need bats to pollinate them are light, bright colors so they can be easily found in the dark. Some even give off special bat attracting odors.

©C.Ziegler/GLOBIO.org

All over the world, several species of plants and trees need bats in order to reproduce. Bat-pollinated plants such as the baobab tree and the saguaro cactus provide food, water, and shelter to many other animals. Many of the foods people eat and the products we use depend on bats, too.

Bats in Trouble

Several species of bats, especially fruit bats, are in trouble. Their forest habitat is being cut down by loggers or being cleared for houses and farms. The bats are threatened by mining, deadly plants that have invaded their habitat, and tropical storms.

In some countries, fruit bats are eaten. Over-hunting has threatened several bat populations to near extinction. Fruit bats are also killed by farmers who think of them as pests. Insect-eating bats have been killed on purpose by people who are afraid of them. They have also been killed by accident by explorers disturbing winter hibernation caves.

It is important to make sure bat populations are healthy. To do this, scientists sometimes catch some of the bats and examine them. This information lets scientists know how the bats are doing.

It is important to make sure bat populations are healthy. To do this, scientists sometimes catch some of the bats and examine them. This information lets scientists know how the bats are doing.

©M.Durham/GLOBIO.org

Protecting Bats

But it’s not all bad news for bats. Conservation groups have helped protect large areas of forest land. Hunting has been banned in some areas. Special gates have been installed across cave entrances to allow bats to enter and leave, but to keep people out. Reducing the use of pesticides on crops is one of the best ways to protect insect-eating bats.

Change Bad Bat Attitudes

The best way we can all help conserve bat populations is to change negative attitudes. Share what you know about bats with your friends and family. Look for bats and study their behavior. Bats are safe to be around. However, if you can get close enough to touch any wild animal, it may be sick and could spread diseases. If you find a bat, never touch it.

Build Your Own Bat Box

You can also help protect bats by asking your family to avoid using chemical pesticides. To attract bats to your area, install a bat box. You can buy one or build it yourself. Plans and directions are available from Bat Conservation International. Bats may not move in right away, but be patient. Soon you may be enjoying summer evenings of bat-watching, with no mosquito bites to scratch the next day.