Dolphins

Dolphins are fast, social sea mammals with a torpedo-shaped body and a curved dorsal fin. In this app the group includes the Bottlenose Dolphin, the Spinner Dolphin, and the Common Dolphin.

The streamlined body, curved dorsal fin, and long snout with many small, cone-shaped teeth mark this group apart from porpoises, which have shorter snouts and spade-shaped teeth. Members are told apart mainly by size, colour pattern, and dorsal fin shape.

A dolphin has a streamlined body, a rounded head, a long snout, and flippers instead of front legs. It has a dorsal fin on its back and a tail fin, called a fluke, used to swim. Size ranges from about 1.7 metres up to the orca, which can reach 9.5 metres.

Dolphins are fast, active swimmers that move by beating their tail fin up and down, using their flippers to steer. Many species leap or porpoise out of the water, and some hunt together in groups, herding fish into tight balls to feed.

Most dolphins eat fish and squid, caught with their many small, cone-shaped teeth. A few larger species, such as the orca, also hunt other marine mammals, including whales larger than themselves.

Dolphins usually give birth to a single calf, which is born tail first in most cases. The time a mother carries her calf varies by species, from around 11 months in smaller dolphins to about 17 months in the orca.

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  Bottlenose Dolphin

  Tursiops truncatus

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  Common dolphin

  Delphinus delphis

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  Guyana Dolphin

  Sotalia guianensis

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  Indo-Pacific Bottlenose Dolphin

  Tursiops aduncus

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  Risso's Dolphin

  Grampus griseus

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  River Dolphin

  Inia geoffrensis