Bats are one of the only mammals known to feed on blood. They are also the only mammals capable of flight. There are more than 900 species of bats found all over the world; some experts say there are more than 1,200 species.
Bats are nocturnal creatures that roost during the day in caves, trees or man-made structures. The largest bat is the flying fox with a wingspan of up to 6 feet (1.8 meters). The smallest is the Kitti’s hog-nosed bat with a wingspan of less than 6 inches (15.2 cm).
Many bats use echolocation when they fly. They send out ultrasonic sounds and listen for variations in the echoes that bounce back at them to navigate.
Bats belong to the order Chiroptera and are classified into two main groups, or suborders: Megachiroptera, consisting of the flying fox family, and Microchiroptera. Megabats are medium-size to large bats. Many eat fruit, pollen or nectar; some eat small animals and fish. Microbats use echolocation to find their prey, typically insects.
Other facts about bats
One species, the vampire bat, feeds mostly on blood. They will bite an animal and lap up the blood from the wound.
Around 70 percent of bats eat a variety of insects. A single little brown bat can eat more than a 1,000 small insects in an hour.
Bats have four strong forelimbs in between a webbed membrane that allows them to fly. These wings are much thinner than those of birds.
When bats roost, they hang upside-down. They wrap their wings around them to stay warm. In the winter, some bats may hibernate for months at a time.
Most female bats give birth to only a single pup each year making some species vulnerable.
About 40 percent of American bat species are in severe decline or endangered.
An anticoagulant in vampire bat saliva has been developed to increase blood flow in patients with stroke or heart disease.