Pacific White Sided Dolphins

Lagenorhynchus obliquidens

Pacific White Sided dolphins are seasonal visitors to the San Diego marine ecosystem. Lagenorhynchus obliquidens or ‘Lags’ are one of our favorite species of dolphins to encounter, not just because they are less commonly found in San Diego, but they also can be very acrobatic and thrilling to observe. We typically see Lags when the ocean temperatures cool down in winter. For the most up to date information visit our Facebook and Instagram pages where we post daily sightings reports, including if we have seen Pacific White Sided dolphins.

Pacific White Sided Dolphin Info

Description – Lags are named for their bright and distinctive coloration. They are a mid sized dolphin (up to 8 feet and 350 pounds) with a robust frame. They have a short snout and a relatively tall dorsal fin.

Range – Pacific White Sided dolphins are a pelagic species that prefer temperate seas. They range across the north Pacific and are found from California to Alaska.

Behavior – Pacific White Sided dolphins are usually found in smaller pods of 10-12 individuals. However, they do form large aggregations of over 1,000, especially during high prey events. In San Diego we usually see these smaller pods. Lags are typically active dolphins that react to the presence of the boat with bow riding and amazing leaps.


The population of Pacific White Sided dolphin along the west coast of the US is not considered threatened. It was recently estimated to be 26,000.

There are still threats of mortality to Lags, mostly from entanglement in fishing gear. Noise pollution is also a concern for the conservation of the Pacific White Sided dolphin.