Toothed Whales, Dolphins, and Porpoises

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Members of this group sighted in waters near the Togiak Refuge are the beluga whale, Cuvier's beaked whale, the killer whale (orca) and the Pacific white-sided dolphin. Belugas are common locally (common in certain areas), killer whales are uncommon, and Cuvier's beaked whales and Pacific white-sided dolphins are rare.

Harbor porpoises and Dall's porpoises also inhabit the waters of the Togiak Refuge. Dall's porpoises are uncommon, while harbor porpoises are considered rare.
 

  • (Odontoceti)

    Marine mammals spend all or the majority of their time in water, and thus are specially adapted to this way of life. Their thick layers of fat help to keep them warm in frigid waters. Since they are mammals, they must always come up to the surface to breathe, although they can often hold their breath for surprising lengths of time.

    Toothed whales and dolphins, along with porpoises, are grouped together in the suborder Odontoceti. They all have teeth, although in some cases these teeth may not erupt through the gums. The size and type of teeth vary depending on the food they eat. The members of this group vary in size from the huge sperm whale, almost 60 feet in length, to comparatively tiny 6 foot long porpoises. All members of the subgroup have only one external blowhole.

    The toothed whales most common in southwest Alaska are the beluga (white whale) and the killer whale (orca). Two species of porpoises are known to occur in waters off Togiak National Wildlife Refuge: the harbor porpoise (Phocoena phocoena) and Dall's porpoise (Phocoenoides dalli). The Goosebeak, or Cuvier's beaked whale (Ziphius cavirostris) and the Pacific white-sided dolphin (Lagenorhynchus obliquidens) have also been reported near the Togiak National Wildlife Refuge, but these sightings are quite rare. 

  • Beluga whale (Delphinapterus leucas)

     Adult belugas are completely white, with a short broad beak and no dorsal fin. Young are slate gray to pinkish-brown, and these colors change to pure white at adulthood. They can weigh up to 3300 pounds and be almost 15 feet in length.

    Belugas are fairly social and can often be seen in large groups called pods. Populations may be stationary or migratory, with the movement patterns being dictated by seasonal ice cover.

    Belugas may be hunted by killer whales or polar bears, although predation is not considered heavy. Native Alaskans also hunt them for oil, muktuk (blubber), and meat.

    Mating occurs in spring and young are born the following summer after 14 months of gestation. Calves, almost 5 feet long at birth, remain with their mothers for two years but are partially weaned after the first year. Females may have calves every two to three years.

  • Killer whale (Orcinus orca)

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     The killer whale is known for its prominent dorsal fin (on its back) and black and white coloration. The triangular dorsal fin may be almost 6 feet tall in males. In females the dorsal fin is smaller and more curved. Killer whales are black with white patches behind the eyes and on the belly and sides. A gray saddle is also found behind the dorsal fin. Males grow to more than 31 feet long, weighing eight tons or more; females are smaller.

    Killer whales are social and live in fairly stable groups called pods. Pods can be a few individuals or as many as 30, with both sexes and a variety of ages included. These pods often hunt together, and virtually nothing in the marine ecosystem is safe from them. They may prey upon other whales, seals, walrus, seabirds, turtles, and a variety of fish.

    Calves are born in the fall and winter, after more than a year of gestation. Calves remain dependent for at least a year. Calves weigh around 400 pounds at birth, and are more than six feet long.The killer whale is known for its prominent dorsal fin (on its back) and black and white coloration. The triangular dorsal fin may be almost 6 feet tall in males. In females the dorsal fin is smaller and more curved. Killer whales are black with white patches behind the eyes and on the belly and sides. A gray saddle is also found behind the dorsal fin. Males grow to more than 31 feet long, weighing eight tons or more; females are smaller.

    Killer whales are social and live in fairly stable groups called pods. Pods can be a few individuals or as many as 30, with both sexes and a variety of ages included. These pods often hunt together, and virtually nothing in the marine ecosystem is safe from them. They may prey upon other whales, seals, walrus, seabirds, turtles, and a variety of fish.

    Calves are born in the fall and winter, after more than a year of gestation. Calves remain dependent for at least a year. Calves weigh around 400 pounds at birth, and are more than six feet long.

  • Resources

     Leatherwood, Stephen and Randall R. Reeves. 1983. The Sierra Club handbook of whales and dolphins. Sierra Club Books. San Francisco California.