The place to be on the ship is up in the bridge. That is the place to see all the animals. We have two different groups of scientists up there from sunrise to about nine at night. We have scientists looking for different kinds of birds and we have scientists looking for ice seals. Sometimes they see other animals. Like today. They saw another kind of cetacean, a porpoise. If you’d like to learn more about them, read on.
Dall's Porpoise
Scientific name: Phocoenoides dalli
Where do Dall's porpoises live? Dall's porpoises only live in the North Pacific Ocean from Japan to Southern California and as far north as Bering Sea.
How many Dall's porpoises are there? We don't know. Although population numbers are unknown, Dall's porpoises appear abundant through their range. Dall's porpoises are not considered endangered.
How can I identify a Dall's porpoise? Dall's porpoises are beautiful! Though individual animal coloring varies slightly, Dall's porpoises are easy to identify as they are mostly black with white along their sides, on the top half of their dorsal fins and on the trailing edge of their flukes. Dall's porpoises mature to around 7 feet (2.1 meters) long and have 19-23 spade-shaped teeth. When swimming, Dall's porpoises leave a characteristic splash called a 'rooster tail.'
How well can a Dall's porpoise see or hear? Scientists don't really know. Captive Dall's porpoises emit low frequency clicks that are presumably used for echolocation.
What do Dall's porpoises eat? Dall's porpoises are thought to have a rather varied diet consisting of hake, squid, lanternfish, anchovy, sardines and small schooling fish.
How do Dall's porpoises have babies? Female Dall's porpoises reproduce at approximately six years of age while male Dall's porpoises mature at 8 years of age. Dall's porpoise calves are born in mid-summer after a 12 month gestation period. They are about 3 feet (0.9 meters) long. Calves and their mothers live separate from main porpoise herds for a time. Dall's porpoise mothers usually have calves every 3 years.
How long do Dall's porpoises live? How do they die? Dall's porpoises usually live about 16-17 years. Very little is known about their mortality however many believe that Dall's porpoises are very susceptible to "incidental" capture by certain types of fishing gear. These porpoises become so intense upon the pursuit of their food that they fail to anticipate or see gill nets set for fish. Porpoises that get entangled in nets usually drown.
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