Since October 1970, the Sarasota Dolphin Research Program has studied the dolphins of Sarasota Bay, Florida, and as of November 2026 it is the longest-running study of a wild dolphin population. Scientists tell individual dolphins apart by the nicks and notches on their dorsal fins. Some bottlenose dolphins live for more than 50 years. A female bottlenose dolphin named Nicklo from Sarasota Bay lived to age 67, and as of November 2026 the program calls her the oldest documented dolphin in the world.

A mother bottlenose dolphin is pregnant for about 12 months, and dolphin calves are usually born tail first. A newborn calf is about 2.7 to 4.6 feet long, and it drinks its mother's milk for about 18 to 20 months. A calf swims close beside its mother, which may help it cut down on drag, and it usually stays with her for 3 to 6 years. In a group of bottlenose dolphins, females can help look after one another's calves.

Look at how a dolphin's body works. A dolphin's brain has no sense of smell, and its belly can turn pink when it is active, which helps it release extra body heat. Near shore, a bottlenose dolphin comes up to breathe about two times a minute. When it sleeps, half of its brain stays awake. A dolphin can see well both underwater and above the water. A bottlenose dolphin can swim about 18 miles an hour for a short burst.

Dolphins find things by making sounds that bounce off objects and return as echoes, and a waxy, lens-shaped part in the forehead, called the melon, focuses the clicks into a beam. Echoes from the clicks are picked up through the lower jaw. Some dolphins find fish by listening for the sounds the fish make. Each bottlenose dolphin develops its own signature whistle, which begins to develop in its first months of life. Scientists think a signature whistle works like a name.

Calves learn how to hunt mostly by watching their mothers. In Shark Bay, Australia, some dolphins wear sea sponges on their snouts while they search the sea floor for food, and calves can learn to use sponge tools from their mothers. Some bottlenose dolphins strand-feed, which means they rush onto mud banks or the shore to catch fish stranded there. At Laguna in southern Brazil, wild bottlenose dolphins chase mullet toward fishers standing in shallow water.

In Sarasota Bay, a boat passes by a dolphin every 6 minutes and 1 in 20 dolphins there has a scar from a boat collision, as of November 2026. As of November 2026, getting tangled in fishing gear is also one of the main threats to bottlenose dolphins. Also as of November 2026, the IUCN Red List lists the common bottlenose dolphin as Least Concern. In the United States, bottlenose dolphins are protected by the Marine Mammal Protection Act of 1972. Feeding wild dolphins is harmful because it teaches them to come close to boats and people. As of November 2026, people should stay at least 50 yards (46 meters) away from wild dolphins.

Words to know

• documented: recorded
• melon: forehead lump
• signature: one's own
• stranded: stuck ashore
• population: animal group