Atlantic white-sided dolphin

The white-sided dolphin (Lagenorhynchus acutus) is black or dark purple to grey, with a yellowish blaze along each side of the tail behind the dorsal fin, and a white band on the flank below the dorsal fin. Below the dark dorsal zone is a pale grey stripe along the length of the body. The belly is a pale, yellowish cream and there are large black genital blazes. There is a dark stripe between the corner of the jaw and the anterior insertion of the flippers, which joins the large dark eye patch.

They have between 29 and 40 teeth. Female white-sided dolphins can reach 2.4m and males 2.7m in length and weigh from between 182 and 234kg respectively.

Where are they found?
The Atlantic white-sided dolphin is only found in the cool waters of the North Atlantic Ocean and is often found along the continental shelf edge. They range from West Greenland to the northern United States in the west, and from Iceland, east Greenland, western Norway and the British Isles in the east. White-sided dolphins have been seen in small groups, but commonly form larger pods of up to 1,000 animals offshore.

What do they eat?
White-sided dolphins feed on small schooling fish and squid. In the western North Atlantic short-finned squid, herring, smelt, and shrimp have also been found in the stomach of several animals.

How long do they live?
Female white-side dolphins are pregnant for about 11 months. The lactation period lasts about 18 months, and they calve every 2.5 years. White-sided dolphins are believed to live for at least 27 years. Sharks and killer whales hunt white-sided dolphins, and mass strandings are common.

Conservation concerns
Atlantic white-sided dolphins are hunted in the Faeroe Islands and Greenland. In the past, more than 500 have been killed in one year in the Faeroes. The catch in southwest Greenland is smaller, probably less than 50 animals.

The dolphins are also killed caught in fishing nets throughout their range. Monofilament gill nets are the biggest threat in the coastal shelf waters of the US, Canada and western Europe.