Bowhead whales are the only whales that spend their entire lives in arctic waters. Those widespread off Alaska spend the winter months in the southwestern reaches of the Bering Sea. In spring, they migrate northward, following the melting of the ice, up to the Chukchi Sea and the Beaufort Sea, hunting for zooplankton, especially copepods.
They are slow swimmers and usually move alone or in small groups of up to six specimens. Although they can stay submerged for up to forty minutes, they are not believed to dive very deep. Bowhead whales have been hunted for their blubber, meat, oil, bones and baleen.
They are closely related to the right whale and like the latter have the characteristic of swimming slowly and floating once dead. Before commercial whaling, it is estimated that more than 50,000 bowhead whales lived in the region around the North Pole.
Commercial whaling began in the 16th century, when the Basques began catching whales in the Strait of Belle Isle as they migrated southward in the fall and early winter. By 1719, whalers had reached Davis Strait, and by the first quarter of the 19th century, Baffin Bay.
In the North Pacific, commercial hunting began in the 1840s, and within the next two decades, 60 percent of the population there had already been exterminated. Commercial hunting, the main cause of the decline of this species, has been erratic.
The population off Alaska increased markedly after commercial whaling ended. The natives of Alaska continue to kill a few specimens every year for their own survival. The status of other populations is less known. Off western Greenland there are 1200 (2006), while the population of Spitsbergen is made up of only a few dozen individuals.
In March 2008, the Canadian Department of Fisheries and Oceans conducted a new census, at the end of which it was reported that there are currently 14,400 bowhead whales in the Eastern Arctic. This number, which matches that of specimens that lived there before commercial hunting, indicates that the population is increasing.
Greenland whales are dark colored, stout-bodied animals with no dorsal fin, with the lower jaw heavily curved and the upper jaw very narrow. The baleen plates, which at over three meters long are the longest of any whale species, are used to trap tiny prey in the water.
These whales have very massive skull bones, which are useful for breaking ice for the purpose of breathing. Some Inuit hunters claim to have seen whales breaking 60 cm thick ice surfaces with this method.