The monodon monoceros, or narwhal or narwhale as it is most commonly known, is one of the rarest and most mysterious whales known to man.

Narwhal means 'corpse whale' in Old Norse. This is most probably due to the adult whale's color, which is bluish-gray with white splotches and a white belly. In addition to their color, the narwhal has a cylindrical body, a round head, a small mouth, and no dorsal fin, being a close cousin of the beluga. Narwhals are fairly small whales, growing to between 13 and 16 feet and weighing between 1 and 1.8 tons. Female narwhals have a 15 month gestation period; the young are born a murky brown color and are about five feet long and 175 pounds, feeding from their mothers for up to two years. They are considered to be one of the most vocal of all whale species.

Adult narwhals have a varied diet, consisting of cephalopods, arctic cod, flounder, mollusks, and various shrimps. Because they have no useful teeth, they use suction and the emission of a jet of water to catch their prey.

Narwhals are most distinguished by a long horn; however, this is no horn. Narwhals have only two teeth, which grow in their upper jaw. Almost exclusively in males, after the first year in life the left tooth begins growing outward. Generally, the tooth grows in a counterclockwise spiral shape and is hollow. This tusk can grow to be 10 feet long and weigh up to 22 pounds. Very few female narwhals--only 3%--grow this tooth, which is thin and relatively short; also, rarely, a narwhal may grow two tusks.

From Medieval times Vikings brought the narwhal's tusk to Europe, either starting or enforcing the belief of the unicorn, and guarding their secret for over 300 years. It was a highly valued commodity, as people believed the unicorn's horn could detect poison in their food. There are only two narwhal horns in existence today dating from Medieval times, carved with foliage and fantastic images of dragons; one is on display at the Liverpool Museum and Walker Art Gallery, with the other in the Victoria and Albert Museum.

It is not known what the precise use of the horn is, though there are many theories. One is that the males use it for dueling/courtship rituals or to show dominance. Another theory is that the horn is used for channeling and amplifying sonar pulses, which the narwhal uses to communicate.

Living in the Arctic, narwhals are rarely seen further south than 70 degrees North latitude and can be found from Canada to Russia and through the Norwegian waters. Large numbers have been spotted in the Davis Strait, near Baffin Bay, and in the Greenland Sea. Their compact shape, along with a thick layer of blubber, helps to retain heat in the frigid waters in which they reside.

Narwhals live in herds consisting of females with calves and several males, usually having similar size and tusk length. As they live in the Artic they rarely stray far from the ice, and so it initiates their migration, as they move from the offshore pack ice into fjords during the mid-summer.

It is estimated that the narwhal population is between 10,000 and 45,000, putting their conservation status at 'special concern'. While the narwhal is preyed upon by polar bears, walruses, orcas, and some sharks, its biggest enemy is man. Pollution of their habitat is part of the problem, but the narwhal is most widely hunted for its tusk, which is prized by hunters and collecters. As a result, even though the hunting quotas are strictly enforced, poaching is still a threat.

The narwhal is and has been traditional prey for the Inuit peoples of Greenland and Canada. Although some tribes still hunt with harpoons from kayaks, most use motor boats and high-powered rifles. The skin is a delicacy known as muktuk, with the tusk being used for traditional items. The flesh is often used to feed sled dogs, and the blubber is rendered down for heating and lighting. Though the narwhal is traditional fare for the Inuit, they have wisely restricted the number they hunt as knowledge has increased about their conservation status.


Sources
http://members.aol.com/puffindog/narwhal.html
http://www.narwhal.info/faq/
http://www.enchantedlearning.com/subjects/whales/species/Narwhal.shtml
http://www.narwhal-whales.com/