Bowhead Whale
The Bowhead Whale is a species restricted to the colder waters of the Northern Hemisphere, and is rarely far from ice. They migrate northwards, following cracks in the ice in the spring, and then southwards again in the autumn as the sea freezes over.
Classification: The Bowhead Whale, Balaena mysticetus, was classified by Linnaeus in 1758, meaning 'moustached sea monster'.
Local Names: Greenland Right Whale; Greenland Whale; Great Polar Whale; Arctic Whale; Arctic Right Whale. The common name is derived from the extreme arching of the lower jaw.
Description: This is a large, stocky whale with no dorsal and a huge head. Though calves are born blue-black, adults are black in colour, with a white/cream ‘chin’ on the forward part of the lower jaw. This lighter patch may contain black spotting. Occasionally there is a smiliar light area on the tail stock. Flippers are small and rounded, and a small eye is set at the angle of the jaw. Females are generally larger than males, with average length being between 14-15m (the longest recorded was 19m), and weighing 50-60 tonnes. The Bowhead Whale has the longest baleen plates of all baleen whales, typically reaching 4.3m in length, with around 700 plates per animal.
Recognition at sea: A large whale with no dorsal can only be a Right or a Bowhead. To discern between the two, the Bowhead's white 'chin' is absent in Right Whales. At a distance, Bowheads do not have the head callosities that are common on Right Whales. The blow is bushy, V-shaped, and up to 6m high.
Habitat: The Bowhead Whale is wholly in Arctic or sub-Arctic waters, occuring mainly in shallow water close to land. However, the species will swim in whatever depth is necessary in order to follow the retreating ice edge.
Food & Feeding: Bowheads feed in much the same way as Gray Whales, in that they are bottom feeders, but do so in water of less than 30m in depth. They are also skimmers, intaking food at the surface by swimming slowly along with the mouth open. They normally take a variety of organisms, including copepods, steropods and euphausiids.
Behaviour: Bowhead Whales often travel in groups of three or less in the spring, but larger groups of around 50 animals are common during the autumn migration. Breaching, lob-tailing and flipper-slapping are rare but not unheard of, and the whales are well-known for their ability to break air holes through ice of less than 0.3m thick.
Longevity: Unknown, but a freshly-killed Bowhead Whale being processed in Alaska in 1995 was found to have two stone harpoon blades lodged in its flesh. These harpoon blades were replaced by the electric harpoon in the late 1800s, so it is possible that the whale was over a century old. In addition, new evidence has suggested that Bowheads can live for 130 years.
Estimated Current Population: < 8,500 animals. Vulnerable.
The Influence of Man: Bowhead Whales were a prime target for whalers, being slow swimmers and yielding good quanities of oil and baleen. Populations were decimated quickly because of the species' ease of capture, and have been under protection from commercial whaling since 1975. Around 50 are still taken every year by Eskimos as a staple food source, and despite early exploitation, it is thought that the Bowhead Whale is recovering adequately.
Source: CETACEA
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