Bats only come out at night because they dislike light and can find more food after the sun goes down. The primary diet of many bat species consists of mosquitoes, which prefer to come out at sunset.
As of 2015, there are roughly 1,000 bat species in the world, and around 70 percent of these species feed on insects. Other species of bats tend to feed on fruits and small animals, such as lizards. Although many people fear bats, they are necessary to keep insect populations under control. For example, one bat can eat up to 1,000 mosquitoes in an hour.