Female bats take care of their young at birth by holding them in a membrane pouch and nursing them. For some time after birth they may carry their tiny babies with them as they feed, but the mothers later leave them at the roost, returning frequently to feed them.
Female bats usually have only one baby at a time, possibly because of the need to fly and feed even while pregnant. When it is time to give birth, the females of some species hang head-up by their thumbs and catch their babies in a tail membrane, while other species hang head-down and catch the baby with their wings. The bat pups are born eyes closed and hairless and cling to their mothers immediately with their sharp claws and sometimes with their teeth.
Depending on the size of the bat species, bat pups may cling to their mothers while they fly and feed for a few days to a few weeks. When they are too heavy to carry, the mothers leave them holding onto a wall, branch, roof of a cave or other shelter while they search for food. The mortality rate of bat pups is high, as some baby bats fall from their perches and are unable to climb back up.
Depending upon the bat species, young bats fully develop their wings and gain the ability to fly within three weeks to four months. When they do, they are responsible for hunting their own food.