Bowhead whale
Balaena mysticetus
Threat Index

Max Length:
Male: 18 m
Female: 20 m
Calf: 4 - 5 m

Max Weight:
Female: 90,000 kg

Est. Population: 12,000

Diet: Krill; copepods

IUCN Listing: LC (Spitzbergen stock listed as CR; Okhotsk Sea and Baffin Bay/Davis Strait stocks listed as EN; Hudson Bay/Foxe Basin stock listed as VU)
CMS Appendix: I
CITES Appendix: I
Synonym:
Arctic right whale, Arctic whale, Polar whale, Greenland right whale, Greenland whale, Bowhead whale

Related Projects:
None

Classification:
The bowhead whale has the longest baleen of any whale with the plates reaching 5m in length (the blue whale's baleen measures just one metre). The second species to become the primary target of commercial whaling, and hunted to near extinction in the middle of the 20th century, four of the five remaining stocks of bowhead whales remain Vulnerable, Endangered or Critically Endangered. Found only in Arctic and sub-Arctic regions, it would be difficult to confuse the bowhead whale with any other large whale as few range this far north except the occasional humpback or grey whale. The distinctive double-humped profile of the bowhead whale at the surface and lack of dorsal fin allows it to be distinguished from any rare visitors. Discoveries of two stone harpoon points from the late 19th century in the skull of a whale killed by Inuits in 1993 prove that the bowhead whale can live to be over 200 years of age – one of the longest-lived mammals yet known.

Appearance:
As their name suggests bowhead whales have a huge arched upper jaw, and their mouthline is strongly bowed. The head is approximately one-third of the total body length and has two blowholes. There is a large indentation behind the blowhole, giving it a distinct double-humped shape, or 'neck', when it surfaces to breathe. They have a distinct V-shaped blow, caused by the wide space between the two blowholes. The bowhead whale has a rotund smooth body with no callosities or growths and a rounded back with no dorsal fin, hump or ridge. The blubber is up to 70cm thick. The bowhead whale is predominantly black in colour with varying amounts of white on the lower jaw of an individual. The black markings on the white jaw each represent a chin hair follicle. There are also grey/white markings around the narrowest part of the tail stock and flukes, which become more pronounced with age. Bowhead whales have wide, paddle-shaped flippers with blunt tips and broad tapered tail flukes measuring up to 6m in length in some animals.

Behaviour:
Bowheads occasionally breach, lobtail and do flipper slaps, and may spyhop when alone. They feed at or just below the surface ('skim-feeding') and possibly along the seabed. Although not much is known about the diving habits of bowhead whales, as with other large whales they are thought to dive to depths of more than 200m, with an average dive time of four to 20 minutes, (although some have been known to submerge for over an hour at a time), often surfacing again in the same place. When they need to come to the surface to breathe, they are capable of breaking through ice up to at least 60 cm thick to make a breathing hole and some authorities suggest that they can break even thicker ice. The mother-calf bond is strong, and young animals are inquisitive and often play with objects found floating in the water. Bowhead whales are rarely found far from the edge of the pack ice and are the only large whales to live exclusively in the Arctic. They generally travel in groups of three or less, but congregate in larger groups on feeding grounds.

Distribution:
Prior to the nineteenth century it is thought that there may have been one single pan-Arctic population of bowhead whales however this species was hunted close to extinction and currently five stocks (distinct populations) are recognised by the IWC. Although the species is listed as Least Concern by IUCN (2008), the status of individual populations is not so positive with the Spitsbergen stock listed as Critically Endangered and the Okhotsk Sea stock as Endangered. Bowhead whales are still targeted in some areas by native subsistence hunts and thus hunting is still a threat to this species, as well as habitat loss, chemical and noise pollution, increased ship traffic and climate change.