Mammals: Bat

Range: worldwide, except for extreme arctic and desert regions Habitat: varied and highly diverse, but most bats live in tropical forests

Bats are myth-understood!

There may be more myths about bats than any other animal. Some people think bats are blind bloodsuckers that fly into your hair and carry rabies. In fact, this flying mammal is extremely useful to humans.

Bats roost upside down, usually in large social groups, in caves, trees, and man-made structures. Some bats migrate to warmer climates during the winter, while others hibernate. One species travels 2,400 miles (3,862.4 kilometers) each year!

Bats great and small

Bats are divided into two major groups. Megachiroptera, or mega bats, are medium-sized to large bats. Many eat fruit, pollen, or nectar; some eat small land animals, and some eat fish. They have big eyes and excellent eyesight. The other major group is Microchiroptera, or micro bats, containing smaller bats that mostly eat insects. They use echolocation, detecting sound waves to navigate and identify the flying insects they eat. Included in this group is the smallest bat, the Kitti’s hog-nosed bat Craseonycteridae thonglongyai.

Up, up, and away

Bat wings contain the same bones as a four-fingered human hand. A thin, strong membrane spreads across these bones, connecting them to the bat's back and legs, like the fabric and ribs of an umbrella. The thumb clings to surfaces when the bat alights. Most bats take off by dropping from a hanging position, and many can’t take off from the ground. Bats land by slowing down until they stall and grabbing hold of a branch or other surface. Some bats perform a flip and then grab hold!

I hear food!

The micro bats use echolocation to find their insect meals. They make high-pitched sounds that bounce off objects and return to the bat as echoes. Bats in flight can distinguish the difference in sound between a tree, your head, and a tasty grasshopper. Bats are not blind, but most have better night vision than day vision. They see in black, white, and shades of gray.

Bat babies

Some male bats sing to attract a mate. Females have only one baby, called a pup, per year, although twins or quadruplets occur in a few species. Some tropical bats can have two pregnancies a year. Mothers nurse their pup for two to six months, then teach it to fly and find food.

What's for dinner?

Mother's milk— All bats live on milk from birth up to six months of age.

Insects— About 70 percent of all bats eat insects: flies, mosquitoes, beetles, and cockroaches. A colony of bats in Texas eats 500,000 pounds (226,796 kilograms) of mosquitoes nightly!

Nectar— Bats that eat nectar are like hummingbirds, with long snouts and tongues that allow them to lap up nectar as they hover. Their hair catches pollen and carries it from flower to flower. Many plant species would not survive without bat pollinators.

Fruit— Fruit-eaters are drawn by the smell of ripe fruit and are important seed-dispersers. Some seeds will not sprout unless they have passed through a bat’s digestive system. Bats are a crucial resident of healthy rain forest habitats. At the San Diego Zoo, the fruit bats are fed nectar and a variety of juicy fruits, including oranges, pears, grapes, and watermelon, as well as bananas and a bat pellet (to supplement their nutritional needs).

Fish, etc.— A few species of bats eat fish, plus lizards, frogs, birds, rodents, and even other bats! These bats kill their prey by biting its head. Fishing bats fly over the surface of the water, use echolocation to find the fish, grab it with their sharp claws, and then move it into their mouth.

Blood— Only three species of bats, found from Mexico to South America, eat the blood of mammals or birds, often domestic animals like cows. These bats make a small, V-shaped cut in the animal’s skin with a bite, then lick up the blood. They don’t suck blood, like the vampire legends say! And licking the blood from an animal’s leg is usually more annoying than dangerous. A chemical in the bat’s saliva keeps the blood from clotting before it's done eating. This chemical could have medical uses for humans. Investigations are being done to see if this chemical can help humans who have blood clots that could cause strokes.

We need bats!

Bats are responsible for pollinating trees, flowers, and cacti. They spread seeds so plants grow in new areas. Bats pollinate avocados, bananas, breadfruit, dates, figs, mangoes, and peaches. These remarkable mammals live together by the millions and each can eat half its weight in insects a night, so they are great at controlling large numbers of pests that harm crops and spread disease. Certain microorganisms found in bat droppings may have important medical uses for humans.

Bats need your help

Without active conservation programs, bats face extinction. Bats have been killed on purpose when people disturbed their caves or hunted them for food or medicine. Contact a local nature center or park to find out if there is a bat club in your area, or join Bat Conservation International. You can start your own club, help protect local caves and other roosting areas, or build a bat house for your yard or neighborhood.