Bats are the only flying mammal in the world. They are not birds. These insect-eating flyers migrate and hibernate. Seven species live in Pennsylvania, including the Indiana brown bat. This species has been placed on the endangered species list.
Most bats produce only one young per year.
Some species form nursery colonies with as many as 1000 females. Unusual describes another infraclass of mammals called marsupials . The Virginia opossum is the only marsupial common in our state. These mothers work hard to keep their species going. They give birth to as many as 18 young.