Atlantic white-sided dolphin

Lagenorhynchus acutus
Atlantic white-sided dolphin


Size: max 2-2.8m

Key features:
- Yellow or tan band on tail stock
- White underside
- White and grey stripes on flank
- Black upper side and dorsal fin

Atlantic white-sided dolphins are robust and have an abnormally thick tail stock. They have a distinct colour pattern; a dark back and dorsal fin, grey sides and white underbelly. They also have a thin white stripe along their flank, which goes to a yellow-tan colour on the tail stock. They have a slopping head and a tall curved dorsal fin.


The Atlantic white-sided dolphin is a fast swimmer revealing only their upper backs as they pass through the water. They are also known for their acrobatics often exhibiting exuberant breaching and tail slapping displays. They are sociable dolphins that like to hang out with large whales, riding in their bow waves.


The range of the Atlantic white-sided dolphin is similar to the white-beaked dolphin; it’s confined to the cool temperate and sub-arctic waters of the North Atlantic especially over the continental shelf and slope.


The major threats towards white-beaked dolphins include entanglement in fishing gear, being caught as bycatch and the overfishing of their prey.

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