Short-beaked common dolphin

Common dolphins live in the sea.

They swim in warm and cool oceans all around the world. Some live near the coast, and some live far out at sea.

Common dolphins live in the Atlantic, Pacific and Indian oceans, in warm and cool waters on both sides of the equator. They are not found in the icy polar seas.

Many live far from shore, over underwater ridges and seamounts, where cold water full of nutrients rises from the deep and brings plenty of food. Others live closer to the coast. There are also separate groups in the Mediterranean Sea and the Black Sea.

The IUCN describes common dolphins as occurring from tropical to cool temperate waters of the Atlantic, Pacific and Indian oceans, in both nearshore waters and open seas thousands of kilometers offshore. They are absent from the Gulf of Mexico and most of the Caribbean, but regular in enclosed seas such as the Sea of Okhotsk, the Sea of Japan, the Red Sea and the Persian Gulf.

NOAA notes they favor continental slopes and features such as ridges and seamounts where upwelling boosts productivity; off the U.S. West Coast they are abundant year-round from nearshore to about 300 miles offshore, linked to the California Current. Their range reaches south to South Africa, southern Australia, New Zealand and Argentina and north to the UK, Norway, Japan and Canada.

Common dolphins eat fish and squid.

They hunt mostly at night, when the fish swim up near the top of the sea. In the day they rest.

Common dolphins eat schooling fish, which swim in big groups, and squid. They usually rest during the day and feed at night, when many fish and squid rise toward the surface from deeper water.

They can dive to about 300 meters, but usually feed about 30 meters down. In the eastern tropical Pacific they are often seen with schools of tuna and flocks of feeding seabirds.

Common dolphins feed mainly on schooling fish and cephalopods such as squid. NOAA Fisheries reports that they generally rest by day and feed at night, typically diving to about 100 feet (30 meters) to catch prey that migrates toward the surface after dark, although they can dive to about 1,000 feet (300 meters).

They often associate with tuna schools and feeding seabird flocks, especially in the eastern tropical Pacific, and have been seen in mixed groups with spinner and striped dolphins. They have many teeth: 40 to 57 pairs of small, sharp teeth in each jaw.

Common dolphins live in big groups.

Sometimes there are hundreds of them together! They leap, flip and swim beside boats, riding the waves.

Common dolphins are very social. They usually travel in groups of hundreds, and sometimes in huge gatherings called mega-pods of thousands, up to about 10,000 dolphins. Scientists think these big groups are made of smaller groups of 20 to 30.

They are energetic acrobats. They leap out of the water at high speed, flip end over end and somersault in the air. They also often ride the wave pushed up at the front of a ship, called bow riding, and have even been seen doing it beside big whales.

Group sizes average in the hundreds, and mega-pods can reach thousands, up to about 10,000 animals. NOAA notes these are thought to consist of subgroups of 20 to 30 individuals, possibly related or sorted by age or sex.

Common dolphins are often active at the surface, porpoising out of the water at speed, flipping and somersaulting. They bow-ride ships for long periods and have been seen riding alongside large whales. Their daily rhythm, resting by day and foraging at night, follows the vertical movements of their prey.

There are millions of common dolphins.

But sometimes dolphins get caught in fishing nets by accident. People are working to make fishing safer for dolphins.

Common dolphins are listed as Least Concern because there are millions of them across the world's oceans. But they face a big problem: getting caught by accident in fishing nets and lines, which is called bycatch.

Some groups are in trouble. Common dolphins in the Mediterranean Sea are endangered, and those in Greece's Gulf of Corinth are critically endangered. People help by changing fishing gear and methods, studying dolphin populations and watching dolphins from a safe distance.

The IUCN's global assessment (assessed 2020, published 2025) lists the species as Least Concern: available estimates total well over 6 million, and many areas, especially in the Southern Hemisphere, have never been surveyed. Bycatch occurs throughout the range; NOAA notes that off California this species has the highest mortality of any cetacean in the drift gillnet fishery.

Regional populations tell a different story: the Black Sea subspecies is Vulnerable, the Mediterranean subpopulation Endangered and the Gulf of Corinth subpopulation Critically Endangered. Prey depletion by overfishing, underwater noise, chemical pollution and climate change also affect some areas. In the United States all common dolphins are protected under the Marine Mammal Protection Act.