Birth and First Days
Bat pups are usually born in late spring and early summer because this is when insects are most abundant. Females usually give birth to a single pup; twins are very rare. As soon as the pup is born, it is caught in mid-air by its mother. The moment of birth is often upside down, when the mother is suspended.
A newborn bat is hairless and its eyes are closed. In the first days after birth, it lives almost entirely attached to its mother's chest. Pups attach to their mother's breast immediately after birth and often continue to suckle even when she flies away. In some species, mothers leave their young in a “nursery”-like area, and it remains a scientifically fascinating question how the mother recognizes her own offspring among the young left together.
Development and Life in the Nest
Baby bats are incapable of flight for the first few weeks, but their wings develop rapidly and within a few weeks they begin to attempt gliding. The first flight usually takes place after the 3rd or 4th week, during which time the mother's supervision is critical because the risk of falling is high.
The wing bones have the most flexible structure of any mammal; the pups' wings rapidly elongate and become covered with a light membrane. Bat mothers not only give their young milk, but also teach them how to fly and navigate. These trainings take place mostly at night.
Sound, Communication and Social Bonding
Baby bats begin vocal communication at a very early age. Each baby has a unique “call” that is recognized by its mother. Bat mothers have an extraordinary ability to distinguish the vocal frequencies of their young. Even in crowded colonies, they only respond to the sound of their own young.
Some studies have shown that baby bats develop similarly to human babies in terms of social bonding, meaning they are prone to play, learning and vocal imitation. The echolocation skills learned as juveniles determine their lifelong hunting habits. This ability is based on the principle of analyzing the return of sound waves that hit objects in the environment. Bat pups communicate by emitting sounds at frequencies too high for the human ear to hear.
Feeding Habits and Cub Diet
The only source of food for baby bats is their mother's milk. In some large bat species, breast milk does not diminish as the young grows; on the contrary, it becomes richer in the first few weeks. The weaning period varies depending on the species, but usually takes place between 6 and 9 weeks. In fruit bats, however, it can last up to 3 months.
After weaning, in insectivorous species, the chick learns how to catch prey by following its mother. In nectar-feeding species, the young are guided to areas where flowers are present and discover how to feed with their tongues. In carnivorous bat species (e.g. vampire bats), the young initially feed on the mother's blood; the behavior of sucking blood directly from another creature develops rather late.
Differences by Species
Fruit bats (also known as flying foxes) carry their young on their backs for a long time after birth. In this species, the size of the young can reach almost 30% of the mother's body weight. In vampire bats, the young are very socially active, gathering together in nursery groups.
Some species of microbats lay their young in narrow crevices in caves, where it is warmer and safer. In some species, female bats alternate caring for their young with other females. This “collective mothering” system increases the cub's chances of survival.
Return to Nature and First Independence
Unable to orient themselves in the air during their first flight experience, many chicks crash to the ground in a short distance. Being more novice than adults, they feed on smaller insects or more accessible fruits. Even after they become independent, baby bats often return to the colony where they were born. In some species, their attachment to this territory lasts a lifetime.
In some species, young bats begin to fly in groups, and these “first hunting groups” increase survival because it is easier to hunt in groups. After completing their first year, most bats prepare for their own reproductive cycle. However, full sexual maturity can take 2-3 years in some larger species.
Conservation and Threats
Baby bats' biggest enemies are birds of prey, snakes and some mammal species. Predators waiting at the cave entrances are a serious threat to pups that have just learned to fly. Since baby bats are usually born only once, the loss of a single chick can have a serious impact on the population.
Sensory Development and Perception
When baby bats are born, their eyes are not fully developed. Nevertheless, their perfectly developed auditory system comes into play for navigation. Echolocation, or echolocation, works like a natural reflex that baby bats start practicing a few days after birth. Echolocation sounds become stronger and more focused as the young grow. Especially when they are 2-3 weeks old, the ultrasonic signals they emit provide a clearer orientation.
Their ear structure is incredibly sensitive. They “hear and see” the world around them by analyzing frequency differences that the human ear cannot distinguish.
Body Dynamics and Adaptation
In the first weeks, mothers constantly lick the chick's wings, which not only provides hygiene but also keeps the membranes moist and flexible. The blood vessels in the wing membrane are very dense and play a major role in regulating metabolism. Due to the high metabolic rate, baby bats can quickly lose weight even during short periods of starvation. That's why it's so critical not to cut the bond with the mother. In some species, the baby has a small ring of hair on its abdomen. This structure helps the mother to find her breast more easily.
Their Role in Scientific Observations and Research
In some laboratories, new sonar technologies are being developed using the sound frequencies of baby bats. The early movement and grasping reflexes of baby bats have inspired robotic grasping technologies. The process of learning ultrasonic sounds by hatchlings is even used in linguistic modeling, as it is similar to the process of language learning in human infants.