Brown Bat

Bats are mammals

Like most mammals, including people, bats have fur, grow up inside their moms, are born live, and nurse milk from their mothers' bodies. Bats belong to a special group of flying mammals called Chiroptera (Ki-ROP-ter-a). This word is Greek for "hand-wing." Bats actually fly with a modified hand.

Bats – the truth, the whole truth, and nothing but the truth

Many people still fear and dislike these winged mammals of the night. Several hundred years ago in Europe, bats were considered evil, dirty, and mysterious. These feelings were passed on through legends.

Today we know that the many myths surrounding bats are false. But, because of these myths, some people still harm bats. In fact, because of human actions, many species have become endangered. Bats play a valuable role in the ecosystem. Worldwide, bats are the most important natural enemies of night-flying insects. In the tropics, bats pollinate flowers and disperse seeds.

The Mega and the Micro

Bats are divided into two main groups, the mega-chiroptera and the micro-chiroptera. The mega-bats, about 150 species, are called fruit bats because many of them eat fruit, nectar, and pollen. They are also called flying foxes because they have big eyes for finding food and they have a face that looks somewhat like a fox.

The micro-bats, all 800 species, are insect eaters. They navigate and hunt by a system called echolocation (EK-oh-lo-Kay-shun). All Wisconsin bats are from this group.



Although most bats have good daytime vision, insect-eaters depend on their unique bat sonar system during the hours of darkness. This system, called echolocation, helps the bat locate and catch its prey. The bat sends out a steady signal of very short, high-pitched sounds that we can't hear. It scans the area, turning its head from side to side, sending out sound pulses through its mouth. The sounds bounce off objects and return to the bat as echoes.

As the bat gets closer to an insect, it sends out more squeaks. These sounds continue to bounce back to the bat's large, sensitive ears until it can tell exactly where the insect is located. Once a bat has zeroed in on its prey, it uses its wings to scoop up the insect.

Do Not Disturb

Many species of bats roost together in large groups (colonies). For some species, there are only a few roosts for all of the individuals of that species. This means that large numbers of a species are vulnerable to the same catastrophe.

Some Wisconsin bat species migrate south for the winter, others hibernate. During the summer, bats store up fat for the winter. When Wisconsin's weather turns cold, bats look for a place to hibernate until spring. During hibernation, they use their stored energy very slowly. If bats are disturbed, they must use precious energy to warm up, become alert, and search for a new hibernation site. This can cause a bat to use 10 to 30 days worth of fat in a few minutes. If they are disturbed too many times, they run out of stored energy and starve before spring. If you know of a place where bats are hibernating, please don't disturb.

Fun Fact

A single little brown bat can catch 600 mosquitoes in just one hour.

Adapted from "Little Brown Bat" - A Project Wild in the City Fact Sheet and from EE News-Environmental Education in Wisconsin, Wisconsin Dept. of Natural Resources.