Little Brown Bats are nocturnal insectivores with 38 teeth. They average between .2-.5ounces, 2.4-3.9 inches long with a 8.7-10.6 inch wingspan. They have a 6-7 year life span and often live beyond 10 years. Little Brown Bats live in groups, however females live in nursery colonies while raising young. Their gestation period last between 50-60 days most commonly producing 1 baby. Sometimes they will have twins. The first 2 weeks of a Little Brown Bats life is spent feeding. The third week consists of flying lessons and at week 4 they are grown adults. They have a top speed of 21mph.