No, bats do not lay eggs. Instead, they give birth to one pub (baby) a year. Bats are classified as mammals, not birds, although they can fly by flapping their wings as birds do.
Bats give birth to pubs when there is a plenty of food available. They mate during the fall and can delay their pregnancy for several months by storing the sperm in their reproductive organs. Usually, they aim to spring season when there is a plenty of food available.
Bats hibernate during the cold seasons. At the end of summer, bats leave for their hibernation sites where they search for partners and exercise their mating process.
There is no exact explanation of how a female and a male bat find each other for mating. Some suggest that female bats choose their mating partners during a swarming (which is also known as autumn swarming). However, that method does not apply for all the bat species. For instance, female horseshoe bats themselves visit males’ roost in order to have discrete mating.
When it comes down to loyalty, most bats are not as loyal as mourning doves. Most species of bats mate with multiple partners. One exception is the spectral bats which are considered monogamous. Because they stick around their nest and protect the young ones while one of the adults is out for hunting food. Pairs also may stay with each other for life.
When it is time to have babies, female bats gather up in a safe and warm place. The selected place is called maternity roost. Some bat species use them as permanent delivery nest and return to it every year.
Usually, a bat pregnancy lasts about 6 to 9 weeks. However, that estimation can fluctuate depending on bat species, climate, and food availability.
Starting from the birth, young bats are suckled by their mother for about four to five weeks. During that period, young ones get big enough to fly and forage for food.
Bats are long livers compared to the other mammals in similar sizes. Their estimated lifespan is about 30 years (the estimation is based on the little brown bats)