Mating and Reproduction in Dolphins

Much of what researchers know about dolphin mating and reproduction, they've learned by observing dolphins in captivity, so it is still unknown if mating and reproduction varies between wild dolphins and those in captivity. The season and time of dolphin breeding also varies between different types of dolphins in different geographical areas, although springtime seems to be the most common time for breeding.

  1. Maturity

    • The age at which dolphins hit sexual maturity, and thus are able to mate and reproduce, varies both by gender and geological location. For instance, in Florida waters, female dolphins reach sexual maturity between 5 and 12 years of age, whereas males average between 10 and 12 years of age. In the central Atlantic, dolphins hit maturity between 7 and 12 years of age. In South African waters, females mature between 9 and 11 years old, and males average 14.5 years old.

    Mating

    • Mating resembles that of land mammals, where dolphins "court" or play for as long as two days. The courtship between a male and female dolphin involves swimming together, petting fins and even head butting and tooth scratching. Males will perform elaborate swimming patterns and calls, although it is unknown as to whether this behavior is to impress females, or if the call is to announce to other dolphins that he has a mate.

    Birth

    • Females will give birth to offspring after a gestation period of 11 to 12 months. To avoid predators, especially from sharks, which can sense blood from miles away, a dolphin birth will be protected by another dolphin in a midwife sort of role. The baby dolphin is delivered out of the mother's body tail first to avoid drowning. Like human birth, dolphins usually give birth to a single infant.

    Infant Dolphins

    • Once the calf is born, the mother and other female dolphins will assist the calf in swimming to the surface for air. Calves feed from their mother's mammary glands, located near the mother's rear. A female can retain her ability to produce milk long after giving birth, and nursing lasts 12 to 18 months. Because calves do not have the physical ability to suckle, mothers use muscle contractions to expel milk for their young.