Narwhal
| The narwhal |
Narwhal or Narwhale (Monodon monnoceros)
is a medium sized toothed whale and posesses a large tusk from a protruding canine tooth.It lives year-round in the Arctic waters around Greenland, Canada, and Russia. It is one of two living species of whale in the Monodontidae family, along with the beluga whale. The narwhal males are distinguished by a long, straight, helical tusk, which is an elongated upper left canine. The narwhal was one of many species described by Carolus Linnaeus in his publication Systema Naturae in 1758.Total length in both sexes, excluding the tusk of the male, can range from 3.95 to 5.5 m (13 to 18 ft).Males, at an average length of 4.1 m (13 ft 5 in), are slightly larger than females, with an average length of 3.5 m (11 ft 6 in). Typical adult body weight ranges from 800 to 1,600 kg (1,800 to 3,500 lb).Male narwhals attain sexual maturity at 11 to 13 years of age, when they are about 3.9 m (12 ft 10 in) long. Females become sexually mature at a younger age, between 5 to 8 years old, when they are around 3.4 m (11 ft 2 in) long.The pigmentation of narwhals is a mottled pattern, with blackish-brown markings over a white background. They are darkest when born and become whiter with age; white patches develop on the navel and genital slit at sexual maturity. Old males may be almost pure white.Narwhals do not have a dorsal fin, possibly an evolutionary adaptation to swimming easily under ice. Their neck vertebrae are jointed, like those of land mammals, instead of being fused together as in most whales. Both these characteristics are shared by the beluga whale.The tail flukes of female narwhals have front edges that are swept back, and those of males have front edges that are more concave and lack a sweep-back. This is thought to be an adaptation for reducing drag caused by the tusk.
Taxonomy
| Kingdom | Phylum | Class | Order | Family |
|---|---|---|---|---|
| ANIMALIA | CHORDATA | MAMMALIA | CETARTIODACTYLA | MONODONTIDAE |
| Scientific Name: | Monodon monoceros | |||||||||
| Species Authority: | Linnaeus, 1758 | |||||||||
Common Name/s:
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Habitat
Narwhale whales are generally seen in groups of twenty to thirty with varying combinations of male, female, and claves. Narwhals can be mainly found in the Atlantic and Russian portions of the Antarctic. Individual narwhals are sometimes seen in the northern portions of the Hudson Bay and Strait, as well as the Baffin Bay, off of the eastern coast of Greenland, and in a relatively narrow area running along the northern end of Greenland to eastern Russia.The narwhal whale population is estimated to be around 40,000, but has also been suggested to be as high as 50,000 individual whales.
Narwhals, being migratory, travel close to the coasts during the summer months, and travel farther away as the winder freeze starts to set in, and spend their winters in packed ice, and thrive in leads and small holes in the ice.
Basic Anatomy
Importance in environment
Whales, like the narwhal, are at the top of the food chain and have an important role in the overall health of the marine environment. Narwhals are also culturally important to indigenous communities in the Arctic. Like polar bears, the narwhal depends on sea ice for its existence and can be directly impacted by climate change.
Benefit for human
Narwhal whales are being hunted by the artic village on canada and greenland for food. In greenland, most of narwhal part are eaten, including meat,blubber,skin, and organs. And their bones and tusks are used for art craftmanship by the native communities.
sources:
http://en.wikipedia.org/wiki/Narwhal
http://staff.washington.edu/klaidre/narwhalfaq.html
http://worldwildlife.org/species/narwhal
http://www.defenders.org/narwhal/basic-facts
http://www.narwhalwhales.com/narwhalhabitat
http://www.iucnredlist.org/details/summary/13704/0
