Bats are small mammals that have the ability of powered flight. They have long been looked upon as nuisances or pests, when quite the opposite is true. All over the world, bats play incredibly important roles in the ecosystems. Unfortunately, as a result of widespread destruction of their habitat and other human activities, many species of bats are already endangered with many others classified as threatened. Building specially designed “bat houses” as a way to provide bats with a safe place to live is quickly growing in popularity as a way to help bats. I worked with the River Bend Nature Center in Faribault to construct bat houses for them. There are around 1000 species of bats in the world, 44 of which are in the United States. (http://www.lads.com/~bbi/aboutBats.html) Different species live all over the world, and feed on such varied things as insects, fruit, fish, blood, nectar, and pollen. Around 60%-70% of the bat species in the world are insect eaters. (http://www.batconservation.org)

There are seven species of bats that are native to Minnesota: the Little Brown, Keen’s Little Brown, the Big Brown, Pipistrelle, Silver-haired, Red, and Hoary. All of these species are insect eating. They are between 3-6 inches long, have a wingspan of between 9-15 inches, and weigh between 0.2 to 1.1 ounces. (http://www.wcco.com/partners/mnzoo/bats.html) The Hoary bat is the largest found in Minnesota, and the Pipistrelle is the smallest. The Little Brown bat is the most common species in the summer. The Big and Little Brown bats are colonial species (they live in groups) and are the ones most often found residing in bat houses. During the summer bats have their pups; usually one or two during June or July. Since Minnesota can get very cold in the winter, most bats will migrate south to warmer climates or hibernate until the weather is warm again.

When people think of bats, often the first thing they think of is a frightening, blood-sucking creature. Actually, only three of the known species of bats feed on the blood of other mammals, and these species are only located in Central America. Bats are so proficient at using echolocation that they will not get caught in people’s hair or even come near to people (unless pursuing an insect). Although there is a myth that bats are carriers of rabies, the myth is entirely untrue and the percentage of bats thought to have rabies is estimated at less than 0.5%. (http://www.lads.com/~bbi/aboutBats.html.

Bats are an extremely important part of the ecosystem wherever they live. In the rainforest there are twenty genera of plants that depend on bats for pollination, and by dispersing the seeds that they eat, bats play an integral role in helping to regenerate the forest after clear-cutting or fires. (http://www.lads.com/~bbi/aboutBats.html) Here in North America, bats also play a vital role in maintaining the ecosystem, since they are the primary predators of night-flying insects. A single little brown bat can catch 600 mosquitoes in an hour! (http://www.ucmp.berkeley.edu/mammal/eutheria/chiroptera.html) An average-sized colony of 150 big brown bats can eat enough pests to prevent 18 million rootworms from attacking the crops of local farmers each summer. (http://www.batconservation.org) Thus the biological success of bats translates into less use of pesticides that can be harmful to the environment. In areas where human activity has reduced the bat populations, the numbers of insect pests have dramatically risen. (http://www.ucmp.berkeley.edu/mammal/eutheria/chiroptera.html)

Because of widespread destruction of their habitat and the use of harmful pesticides, many bat species are endangered or have already gone extinct. In the United States, almost 40% are already endangered. (http://www.ucmp.berkeley.edu/mammal/eutheria/chiroptera.html) Since every species has its own special role in its ecosystem and its own ecological duties to fulfill, the loss of any species will affect all the other organisms in the ecosystem.