Male bottlenose dolphins do not reach maturity until around the age of ten, while females reach maturity and can begin breeding between the ages of five and ten. These dolphins are very social animals and exhibit a wide range of behaviors throughout their life cycles.
During breeding season, males often compete for access to females and have been observed herding groups of females, so they remain in one area until they are ready to mate. Mating occurs belly to belly, as both male and female dolphins have slits in their bellies that harbor their reproductive organs. The gestation period is approximately 12 months, and females reproduce every two to six years. Calving takes place all throughout the year, but in some areas, it is concentrated in the spring and fall. A single calf is usually born, though twins are possible.
Calves nurse for more than a year and remain with their mothers until they are at least 3 years old. During this time, the young dolphins learn how to hunt and fish. After they are weaned from their mothers, the young dolphins, especially males, leave to find or form a new group.
Bottlenose dolphins are distributed throughout the world's tropical and temperate oceans. They are most commonly found near shorelines, estuaries and harbors. Adult males often live alone or with just a few other males. Females, on the other hand, live in groups of around 15 other females and young. Due to the intelligence and social tendencies of each individual, the group dynamic changes constantly.