Iowa is home to 13 species of bats, although some species are very rare. All bats that reside in the state are insect eaters. The three main species found here are the Big Brown Bat (Eptesieus fuscus), the Little Brown Bat (Myotis lucifugus) and the Red Bat (Lasiurus borealis). 
A common misconception about the bats we have in Iowa is that they migrate south in the winter like most birds. In reality they actually go into a form of hibernation and typically reside in structures like attics, walls and crawl spaces. Customers often realize they have bats during the winter months when they hear scratching noises in localized areas of their homes. In some cases when the weather goes through large fluxes in the winter, bats will awaken and have been known to follow the warm air from heating vents and end up in the living quarters of homes. In the warmer months, clues that you may have bats include hearing scratching, finding droppings in the attic or outside and witnessing bats leaving and returning to their roosting spots in the evening and morning.
Bats are extremely beneficial to the environment. A Little Brown Bat can eat anywhere from 600-1200 mosquitoes in one evening. This can add up to being up to 125% of the bats own body weight in bugs. Not only are they helping humans from being bitten by pesky mosquitoes, bats also consume large amounts of bugs that cause damage to crops.
Bats breed in late fall, but delay fertilization until the late spring. Gestation takes approximately 50-60 days and usually only one baby is born. Birthing and weeing takes place on average June through July depending on the weather. Usually when large colonies are found in the spring and summer they are maternal colonies.
A catalyst for people’s fear of bats is the swooping motion associated with bats’ flying. The reason they swoop is not because they are trying to attack. Unlike birds, bats cannot simply take off from a flat surface. Bats have to start at a high point and basically fall to be able to catch air under their wings to start flying, hence the swooping motion.