Pacific White Sided Dolphin is a long name for a relatively small marine mammal. And the Latin name is even more of a mouthful, so they are also called Lags for short. It’s a much easier name to explain exactly what species of cetacean is seen, especially over a marine radio.

Pacific white sided dolphin leaps in front of MV Gikumi

Pacific white sided dolphin leaps as whale watching boat MV Gikumi approaches

These gregarious dolphins travel in groups that, on occasion, reach numbers of up to approximately 3,000 which is a spectacular sight I have only seen once in all these years. Most frequently their groups are between 20 to 100. If you don’t see more than a couple, you might want to keep a look out, there are usually more not too far off.

Lags can travel quickly reaching speeds of up to 25 knots (almost 30 mph or 47 kph) effortlessly. They are very acrobatic and their frequent airborne flips and leaps can reach extreme heights. These leaps can help distinguish a smaller group of Pacific White Sided dolphins from Dall’s porpoises when they are in feeding mode and only seem to be creating splashes. Somehow, they can’t seem to resist a good leap for too long. One of the alternating photos on the top of this page shows a group chasing fish directly towards my boat after using the sound of the boat motor to help them corral fish. These are not dumb animals. There are many encounters and observations of them that has shown their intelligence and playfulness.

With such an affinity for these dolphins, people have asked why this species was not the first species description I wrote about for this site. Even the Whales and Dolphins of BC logo is a photo of a joyfully leaping Pacific White Sided Dolphin out in front of Powell River on the Sunshine Coast January 2010. There is so much for me to say about Pacific white sided dolphins, that I was concerned I would not stop writing about them. Even just thinking about them, they always make me smile. I will be writing more about boating, kayaking and watching these wonderful marine mammals, but the identification of this species must follow for now.

Pacific White Sided Dolphins – Lagenorhynchus obliquidens Specifics:


Pacific white sided dolphin leaping

Pacific white sided dolphin leaping

up to 2.5 m (8 ft)


up to 180 kg (397 lbs)


Dark grey – black on back

Light grey flanks

Light grey stripes along the sides

White underside

Light grey on trailing side of dorsal


Black and grey noticeably curved dorsal fin

Sleek tapered body with thick tail stock

Short beak with black lips

Curved pectoral flippers

Black tail

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