Narwhal

The narwhal (Monodon monoceros) is famous for the long ivory tusk which spirals clockwise several feet forwards from its head. The tusk is actually the whale's left tooth. Male narwhal, and some females, have two teeth. Usually only the left tooth becomes a tusk, but there are occasionally whales with double tusks.

The narwhal tusk probably plays no role in feeding because males and tusk-less females consume the same diet. Scars on narwhal males possibly indicate that they use their tusks to establish dominance over other males, perhaps during mating.

Narwhals have small, rounded heads and short flippers with upturned tips. Skin colour changes with age; newborns are mottled blue-grey, juveniles are completely blue-black, adults are mottled grey and old narwhals are nearly all white. Narwhals, like other arctic whales, lack a dorsal fin but have a tough dorsal ridge along their spine. Narwhals have a thick layer of blubber, which insulates them from the icy, arctic waters. Males are larger than the females. The largest reach around 4.9m.

Where are they found?
Narwhals spend their lives in the arctic waters bordering Russia, North America, and Greenland. In the depths of winter, when the seas are frozen with ice up to a metre thick, the narwhal has adapted by finding cracks in the ice called "leads", or areas of water that remain open year-round called "polynas", where the whales can surface to breathe.

What do they eat?
A narwhal's diet includes squid, halibut, shrimp, arctic cod, rockfish, flounder, and crab, which are found both at the floe edge, and in the ice-free summer waters.

How long do they live?
Female narwhals reproduce after five years, with males beginning to breed when they are eight-years-old. Calves are born after a 15-month gestation period, usually in July, the beginning of the ice-free summer months. Female narwhals usually give birth every three years. Narwhals may live for 30 to 40 years. Killer whales, which do not live year-round in the Arctic, but often travel through arctic waters, prey on narwhals. Inuit hunters report that killer whales may follow pods of narwhals.

Narwhals and hunting
Narwhals are hunted by some northern indigenous cultures. This subsistence hunt provides food and materials for traditional needs. The skin of the narwhal, called "maktaq" by Canadian Inuit, is eaten both raw and boiled, and the meat is eaten by the people, or fed to sled dogs. The tusk of the narwhal, made of ivory, is used for carving. Crafts made from this ivory are sold and can be an important source of income for Inuit artists. Some researchers believe that not enough is known about the size and stability of narwhal populations, and that care must be taken to not deplete the stocks through over-hunting.

Conservation concerns
Modern threats to this species include habit loss, and toxics and pollution that accumulate in the Arctic and which affect the health and reproduction of these whales. Researchers are working with aboriginal groups to ensure that narwhal hunting is carried out in a sustainable way, so that populations remain stable.