The Narwhal is a medium sized toothed whale that has a long tusk protruding from a canine tooth. For both sexes, the body size can range from 3.95 to 5.5 meters, but the males are slightly larger than the females. Narwhals do not have a dorsal fin and their neck vertebrae are jointed, not fused like those of most dolphins and whales.
In the winter, the Narwhal feeds on benthic prey like flatfish under dense pack ice. During the summer they eat arctic cod and greenland halibut along with other fish such as polar cod.
Threats to Narwhals
Narwhals can live up to 50 years. They are often killed by suffocation when the sea ice freezes over. Another cause of fatality, specifically among young whales, is starvation. The current population of the narwhal is about 75,000, so narwhals qualify for Near Threatened under the criterion of the International Union for the Conservation of Nature. Narwhals have been harvested for over a thousand years by people in northern Canada and Greenland for their meat and ivory.
Females start bearing calves when six to eight years old. Adult narwhals mate in April or May when they are in the offshore pack ice. Gestation lasts for 14 months and calves are born between June and August the following year. As with most marine mammals, only a single young is born. Newborn calves average 1.6 metres in length and are dark grey.
As with most toothed whales, narwhals use sound to navigate and hunt for food. "Clicks", "whistles" and "knocks", may be created by air between chambers near the blow-hole, and reflected off the sloping front of the skull. These sounds are then focused by the animal's melon, which can be controlled by musculature.