Atlantic White-Sided Dolphin

Category: Sea Life

The Atlantic white-sided dolphin is a short-beaked oceanic dolphin that lives in the northern Atlantic Ocean.

Atlantic White-Sided Dolphin

Atlantic White-Sided Dolphin

Scientific & Common Names

Class: Mammalia

Order: Artiodactyla

Infraorder: Cetacea

Family: Delphinidae

Genus: Lagenorhynchus

Species: L. acutus

Common Names: Atlantic White-Sided Dolphin


This dolphin features a body type similar to most other short-beaked oceanic dolphins, with a sleek overall shape and a sickle-shaped dorsal fin. It is colored black above with gray sides and a white underside, with black pectoral fins. Its most distinctive feature that helps separate it from other short-beaked dolphins is the large patch on either side that runs diagonally from the dorsal fin to the tail. The patch is white near the dorsal fin, and becomes yellowish as it reaches closer to the tail. These dolphins can reach up to 9 feet long and weigh over 500 pounds when full grown.


Gestation lasts around 11 months, and these dolphins are believed to breed once every two years. Calves are weaned from their moths at 18 months.


Like most dolphins, Atlantic white-sided dolphins are very social animals and can gather in pods of up to 500 individuals. While traveling, they often breach or jump completely out of the water, engaging in all sorts of aerial acrobatic tricks. They eat a wide variety of fish and sometimes squid


The Atlantic white-sided dolphin was first named by John Edward Gray, a British zoologist, in 1828. It’s genus “Lagenorhynchus” means “bottle-beaked”, while its species name “acutus” means “sharp”, referring to its pointed dorsal fin.

Present status

The Atlantic white-sided dolphin is a species of “Least Concern”. This species has been historically hunted in Norway and Newfoundland, but these hunts have recently been stopped.

While the overall population is not in immediate danger, the dolphins in the North and Baltic Sea, as well as the British and Irish populations, are known to be harmfully affected by water pollution.



2. Shirahai, Hadoran & Jarrett, Brett (2006). Whales, Dolphins & Other Marine Mammals of the World. Princeton, New Jersey: Princeton University Press.