You might see a pod of them off in the distance, plowing up water in plumes of bubbles and spray, arcing, crossing each others’ paths, zipping like mad across the sea’s surface. As they speed toward your boat, you can almost hear the sound effects that accompany the Tasmanian Devil’s entrance in the Warner Brothers Cartoons. “Dall’s Porpoises!”
At an average length of 6 feet (1.8 m) and distinctively marked in black and white, they look like miniature versions of Orcas. And they love small boats. On any given outing here in Resurrection Bay, you can almost count on a group of these speedsters showing up around your bow. And since they seem to prefer to play around boats that are running fairly slowly, they don’t discriminate between powerboats and sailboats.
Dall’s porpoises frequently come right alongside small boats, seeming to use the vessels as objects to play around and to race against. Here a group of them are cutting back and forth beneath our C-Dory.
Strictly speaking, Dall’s porpoises don’t really “porpoise.” They quickly surface, throwing up rooster tails of spray as they do, take a quick breath and keep on swimming. Fast. Photographing them is a matter of guessing where they’ll show up next and snapping shots until they do.
Like other dolphins and porpoises, Dall’s have teeth. They feed on small fish, such as herring. We’ve noticed that when we’re trolling for salmon, right about the time we spot Dall’s, our rods often start arcing and our reels start singing – probably because both the porpoises and the salmon are keying on herring.
Although groups typically contain a handful of individuals, there are times when they gather by the thousands. They roam both nearshore and offshore waters in the Northern Pacific. Unfortunately, although they are still common, hunting (several countries take an average of 10’s of thousands annually – an unsustainable number) and fatal encounters with fishing nets are reducing their numbers.
A good place to read more is in the book Whales and other Marine Mammals of British Columbia and Alaska, by Tamara Eder.