Bowhead Greenland Right Whale

One of the first biological descriptions of the bowhead or Greenland right whale (Balaena mysticetus) is given in the book Drie Voyagien gedaen na Groenlandt, published around 1668 by Gillis Joosten Saeghman in Amsterdam. This book reveals that 17th-century whalers knew a great deal about the biology of whales, probably because they were not only excellent hunters but also very good observers. Thanks to information from such historical sources and data from recent biological research in Alaska, it is possible to give a description of the Greenland right whale.

Greenland right whales have a circumpolar distribution and are endemic to Arctic and Subarctic waters. It is a large whale that belongs to the family of the baleen whales (Balaenidae), which have baleen plates hanging down the upper jaw across the length of the mouth. With these baleen plates, sometimes more than 4 m long, the whale can sift the zooplankton out of the sea water. The Greenland right whale has 250-300 plates in each of two rows hanging down the upper jaw.

The length of the Greenland right whale varies between 12 and 18 m; although a whale can reach lengths of 20 m, only a few exceed 18 m. At birth, the length is about 4 m. In general, females are longer than males. After the feeding season the animal has a layer of blubber approximately 60 cm thick, which helps protect against extreme cold, and the average weight of an adult whale is about 75-100 metric tons. The body coloration is black, but there is a white spot on its "chin" on the lower jaw, and a light spot on the tail and/or fluke plates. The skin is smooth. The throat, chest, and belly lack ventral grooves and the back is smooth with no dorsal fin or ridge as other related species have.

The head is very large, about one-third of the total body length, and the bonnet callosities characteristic of this family are absent on the upper part of the head. The Greenland right whale has a higher arch of the upper jaw than related species, such as the northern and southern right whales (Eubalaena glacialis and Eubalaena australis). This high, bow-shaped head gives the Greenland right whale its common name— bowhead—and distinguishes bowheads from other whales. The arched head may be an adaptation that enables the whale to break through ice to breathe. The widely separated blowholes cause a double blow, the V-shape of which is characteristic of the Greenland right whale. The eyes are placed quite low on the sides of the head, about 30 cm above the corner of the mouth.

The Greenland right whale is a slow swimmer. It can remain underwater for more than 40 minutes, but it is not a deep diver. The whale spends a great part of its life close to the edge of the pack ice near the Arctic and Subarctic islands. From historical sources, it appears that the 200 m depth contour is of great significance to them. Both biological research and historical sources have demonstrated that because of their short baleen plates, young Greenland right whales use these shallow waters to feed on benthic prey as gammarid amphipods.

Adults feed primarily on small to medium-sized zooplankton, animals (euphausiids, copepods, mysids,

Bowhead or Greenland right whale (Balaena mysticetus), Nunavut, Canada.

Copyright Paul Nicklen/National Geographic Image Collection

Bowhead or Greenland right whale (Balaena mysticetus), Nunavut, Canada.

Copyright Paul Nicklen/National Geographic Image Collection and pteropods) found in concentrations along the ice edge near islands in the (sub) Arctic seas, at places where there are many nutrients. This availability of nutrients and the thickness of the ice determine the growth of both phyto- and zooplankton. This growth shows a seasonal rhythm with the peak coming later with increasing latitude.

In the springtime, the Greenland right whale migrates to the north to feed on this zooplankton and returns south in the autumn after the feeding season. It usually does not go farther south than 68° N. Archaeological excavation of 16th-century Basque whaling stations in Red Bay, Labrador showed, however, the existence of this whale species south of 52° N in the Gulf of St Lawrence in those days. The Greenland right whale usually travels alone or in small groups. Concentrations of hundred or more individuals are sometimes seen on the feeding and mating grounds.

The mating time is probably in July-August, but there are indications that Greenland right whales already mate in May-June when they are ice bound during their migration. The gestation period is believed to be 10-11 months long so that the parturition will take place in the spring and early summer. There are some historical sources, which confirm a parturition in the early summer. The lactation period lasts at least one year. The young animals are mature within two years, and the maximum age of a Greenland whale will be between 30 and 40 years.

The only natural predator is the killer whale (Orcinus orca). Other natural causes of death are starvation from lack of access to feeding grounds and suffocation under ice. However, most Greenland right whales die because of whaling. While indigenous peoples have hunted the bowhead whale for subsistence food and oil and as a ceremonial structure for centuries, commercial whaling began in the 16th century. Whalebone corsets were made from the baleen, and whale oil was used in lamps. The animal was very easy to catch because it is a slow swimmer and floats after being killed due to the thick, buoyant blubber. From the estimated number of 90,000 Greenland right whales at the onset of the international whaling trade, only 1000-3000 animals remain. Bowheads were classified as endangered on the US Endangered Species Act in 1969, and the Convention on International Trade in Endangered Species (CITES) prohibits the trade of whalebone. In 1937 when the first international convention was signed, the whaling nations also agreed on the complete protection of the Greenland right whale. From this moment on, no hunting took place on this whale but the damage to stocks had already happened. From the stocks existing in the Sea of Okhotsk, Bering Sea, Hudson Bay, Davis Strait, and Spitsbergen, only one survived in significant numbers, namely the Bering Sea stock. Nowadays only the traditional Inuit whalers from Alaska and Canada and the native Yupik people of Chukotka have permission to kill a limited number of Greenland right whales according to a quota set by the International Whaling Commission. The Inuktitut name for the bowhead whale is arvitt or arviq and the Inupiat name is agviq or aghveq.

Louwrens Hacquebord

See also Alaska Eskimo Whaling Commission (AEWC); Convention on International Trade in Endangered Species (CITES); International Convention for the Regulation of Whaling; Marine Mammal Hunting; Whaling, Historical; Whaling, Subsistence

Further Reading

Burns, J.J., J.J. Montague & C.J. Cowles (editors), The Bowhead Whale, Special Publication Number 2 (Lawrence), 1933

Hacquebord, L.,"The hunting of the Greenland right whale in Svalbard, its interaction with climate and its impact on the marine ecosystem." Polar Research, 18(2) (1999): 375-382 Leatherwood, S. & R.R. Reeves, Whales and Dolphins, San

Francisco: Sierra Club Books, 1983 Nerini, M.K., H.W. Braham, W.M. Marquette & D.J. Rugh, "Life history of the bowhead whale, Balaena mysticetus (Mammalia: Cetacea)." Journal of Zoology, 204 (1984): 443-468

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