The biggest porpoise, alone in its genus
Dall’s porpoise is the largest of the world’s porpoises, thickset and powerful for its size, and it’s the only living species in the genus Phocoenoides. It favors cold, offshore Pacific water rather than the shallow bays and estuaries some other small cetaceans prefer, and it’s rarely seen resting still at the surface for long, favoring near-constant, fast swimming.
A squid-and-fish hunter in deep, cold water
Recorded prey for this species is a mix of small schooling fish and squid, including eulachon, capelin, Pacific hake, and several deep-water squid species like the armhook and gonate squids. That diet points to a porpoise that dives well below the surface to feed, chasing prey that itself lives in cold, food-rich water rather than staying in the shallows.
Mostly an Alaska animal, with a Pacific-wide range
The great majority of records for Dall’s porpoise come from Alaska, with smaller but consistent numbers off California and a handful from Washington. Nearly all recorded sightings sit right at sea level, which fits a species that lives its entire life at the surface and in the water column rather than ever coming ashore. Sightings peak in early-to-mid summer, when Alaskan waters see the heaviest observation effort.
Long-lived, but slow to reproduce
A Dall’s porpoise can live past 20 years, but it doesn’t rush into that lifespan. Females don’t mature until around age five, males closer to six and a half, and pregnancy runs close to a year before a single calf is born, an event that happens less than once a year on average. No predators show up in the interaction data for this species, though that likely reflects what has been documented rather than proof that nothing hunts it. The IUCN lists Dall’s porpoise as Least Concern.
