The Dall’s porpoise is a speed demon, well known to mariners on the British Columbia coast for its habit of riding the bow waves of passing boats. Although they ride in both bow and stern wakes of boats, they seldom stay for very long. They live throughout the coastal waters of the Pacific Northwest and Alaska. Fully grown, it is only slightly more than two metres (6.6 … This creates a spray called a “rooster tail”.

Fig. There is no Dall's porpoise fishery in the United States, but it is estimated that about 30 animals per year are killed as a result of being caught in fishing nets in Alaska. They are a very active species and they are among the fastest swimmers in the cetacean family, clocking up to 55 kilometers (34 miles) an hour. It came to worldwide attention in the 1970s when it was disclosed for the first time to the public that salmon fishing trawls were killing thousands of Dall’s porpoises and other cetaceans each year by accidentally capturing them in their nets.

I have not heard of any the other way around. These “hybrids” have the speed characteristic of the Dall’s and the appearance of the Harbour porpoise. Although they ride in both bow and stern wakes of boats, they seldom stay for very long. Dall’s Porpoises are hugely active creatures. Dall’s Porpoise. It is named for William H. Dall (1845-1927), an American naturalist working with the U.S. Geographical Survey from 1884 to 1909. They will often zigzag around at great speed on or just below the surface of the water. Dall's porpoise (Phocoenoides dalli) is a small toothed cetacean, widely inhabiting the North Pacific Ocean and adjacent seas, between about 30 and 62°N; however, only limited studies of its ecology have been made in nearshore areas.A cetacean sighting survey lasting 60 days was conducted during the 2012 summer cruise of the T/S Oshoro Maru (Hokkaido University, Japan) in the North …

Dall’s porpoises are social creatures, usually living in groups of between 2 and 12 porpoises, although they may gather in much larger groups of up to 200 when feeding. Dall’s porpoise mothers usually have calves every 3 years. The Dall’s porpoise is a speed demon, well known to mariners on the British Columbia coast for its habit of riding the bow waves of passing boats. These “hybrids” have the speed characteristic of the Dall’s and the appearance of the Harbour porpoise. Porpoises range in size from the 1.4 m (4 ft 7 in) and 54 kg (119 lb) Vaquita to the 2.3 m (7 ft 7 in) and 220 kg (490 lb) Dall's porpoise.

was large, was calculated based on the ship's speed (10 knots, or 300 m per min.)

They are about 3 feet (0.9 meters) long. Dall’s porpoises are speed demons.

Dall's do not jump very often, but when they are swimming at speed, its head and back produce a spray called a "rooster tail."

“Dall’s porpoise generally prefer open or deep water, where they can use speed to escape predators,” says study leader John Moran, fisheries biologist of the Alaska Fisheries Science Center. Open circle indicates school of dalli-types, closed circle that of … When the porpoises rode the bow wave, the ship's Dall's porpoise sightings, surface water isotherms (dotted lines, in centigrade), and the track lines of the Toshimaru No.