Michigan Spring Bats:

Michigan Spring bats are organizing their nursery colonies and getting ready to have their pups soon. Mating is random and promiscuous. Both males and females mate with more than one partner. The female can then hold the sperm allowing conception after the winter months occur. As a beginning to mating season, you may see large swarms occur during late summer and fall.  Once the young are born, they are dependent on their mother for food and warmth. At about one month of age, they can fly and catch insects on their own. Each mother has one pup a year and can identify her offspring based on scent and calls. Individuals usually live to six or seven years.

Brown Bat Habits:

To locate their prey, bats use a system called echolocation. This supersense is similar to sonar used in ships. The bat emits a high frequency sound that bounces off objects in their environment. They can then determine the location and size of prey by listening to the sound echo that returns to them. Little brown bats are nocturnal and hunt most actively for a few hours after dusk. They must eat half their body weight in insects per night to prevent malnourishment. New mothers sometimes eat more than their own body weight in a single night.

Eating insects plays an important role in the bats’ ecosystem by controlling bug populations near their roost sites.