Wherever they decide to go, Green Bay bats always move in groups. They are social beings who, over the decades have developed their seasonal habits. How does a bat's life cycle develop?
Summer belongs to the birth of babies. Each female generally gives birth a baby per year. Throughout their lives over the centuries, bats have evolved their biological cycle by dedicating the warmest and most welcoming season for the birth of their puppies so that mothers had plenty of food for themselves so they could feed the babies.
Moreover, summer is the best time for the growth of puppies that, in turn, will be ready and grown to face the cold of winter.
The period goes from 40 to 50 days, when the Wisconsin female feels to have arrived at the end of the gestation that lasts from 40-50 days she joins in a group together with other mothers.
This group is called Nursery.
The mother will give birth in the summer and her baby will immediately be ready to breastfeed while she feeds on the placenta. After about 10 days the baby will already have the fur, the teeth and will see, but only after about five weeks he will be weaned and learn to hunt.
Mating occurs during the fall: large groups of Green Bay bats move flying at sunset for three to four hours: this activity is called swarning.
During swarning,the females are in the heat but the actual mating will take place inside the shelters.
Even if the female is in full inspiration, this does not mean that after mating she will be fertilized.
In fact, she is not ovulating and the spermatozoa will remain alive for the whole time of hibernation (winter) and then fertilize the egg in spring and give birth to the baby in the summer.
Like any Green Bay mammal, bats are homeothermic beings: they are able to regulate the temperature of their body and in winter it is much lowered.
The Wisconsin bat enters this phase called hibernation in which it is able to lower its temperature up to 1 ° higher than the environmental temperature or even manages to go apnea from 60 to 90 minutes, slowing down its heartbeats and stopping, then, the spermatozoa that will be ready for fertilization that will take place in the spring.
This succeeds in doing this because during the summer it feeds enough to be able to overcome the period of hibernation with the excess fat.