They use an amazing technique called echolocation. Using high-pitched squeaks beyond the frequency of human hearing, bats navigate and locate prey in the dark by interpreting echoes produced when their calls bounce off objects. Contrary to popular belief, bats are not flying mice. Bats are sometimes small and brown, but they are not rodents. The bat is the only mammal that has evolved true flight.
Bats provide invaluable ecological and medicinal services.
The little brown bat, for example, can eat up to 600 insects in an hour. Moreover, a colony of 150 big brown bats, common in Colorado's urban areas, can consume 18 million or more insects each summer. In the tropics and southwest deserts, bats are very important as pollinators, and there are unique organisms in bat droppings that scientists are developing for use in products ranging from antibiotics to detergents. Although none of Colorado's 18 bat species are listed as endangered, many are in decline. More than 40 percent of the bats in North America are considered endangered.