After the calf is born, it immediately swims to the surface for its first breath of air. A newborn dolphin is about a third as long as its mother. Female dolphins, like all female mammals, have special glands that produce milk. The calf sucks the milk from its mother's nipples. The females nurse and protect their young for more than a year.
Male dolphins take no part in caring for the young.
Most species of dolphins live at least to 25 years of age. Some pilot whales reach 50 years of age. Sharks are the chief natural enemies of dolphins. Some dolphins die after swimming into extremely shallow water and stranding themselves on the shore. The animals cannot live long out of water because their bodies become overheated.