A gray bat can consume up to 6000 insects a night. High on the food list for Missouri bats are moths, mosquitoes, and other night flying insects. Bat guano, or droppings, is very useful stuff. Guano forms the base of the food chain in many caves, utilized by micro-organisms and invertebrates, which become food for salamanders frogs, and other larger animals. Bat guano has also been used for fertilizer, and in cosmetics.
Bats have odd sex lives.
Even though mating takes place in the fall, conception does not occur until spring. Males do not care for the young. Because of these differing ranges of hearing, people should avoid whispering around bats, or making metallic sounds, such as jingling keys. Both emit frequencies which are quite distracting to bats. Indiana Bats helped to save the Meramec River from an Army Corps of Engineers dam project in the early 1970's.