The scientific name of narwhals, Monodon monoceros, means one tooth and one horn, and it highlights the most unique aspect of these marine mammals, nicknamed sea unicorns. It’s thought that the single large tusk from these animals is behind the legend of the unicorn in cultures that had never seen a narwhal. Despite man’s fascination with their appearance, the fact that narwhals often live in places far from humans means that scientists still have many unanswered questions about the narwhal’s life and behavior.
Narwhals are Whales
The narwhal is a type of whale, a member of the Monodontidae family. This is a very small family of whales -- the only other living member is the beluga. Like all whales, narwhals have blowholes that allow them to breathe when they break the surface of the water. When they dive, the blowholes close, preventing them from accidentally breathing in a lungful of the ocean. Their blowholes are set on top of their heads, a bit further back than their eyes.
Description of a Narwhal
Narwhals are on the small side for whales, with males getting no more than about 16 feet long and females only reaching 13 feet. They are long and sleek, with necks that are more flexible than many whales, but not as much as the necks of the belugas. They have round, domed heads -- the dome is also known as the melon -- and skin that is gray in youngsters but turns black and white as they age. They lack any kind of a dorsal fin but do have an irregular ridge running along their backs. Males have a large tusk that sticks out of the left side of the face.
Survival Under the Ice
Narwhals can stay under water for up to 20 minutes at a time. During this period they dive deep and have been tracked swimming down more than a mile in search of fish, squid and other prey. Though the deep water remains unfrozen, narwhals must eventually surface to breathe. They use their melons and tusks to break through thin surface ice as it freezes, to their keep breathing holes open; the opening must be large enough for the narwhal to get his blowhole out of the water or he will drown. A sudden hard freeze or a shift in the ice can quickly kill all the narwhals in an area.
The Narwhal’s Distinctive Tusk
The most obvious feature of a male narwhal is his tusk; females may sometimes grow tusks but never to the extent that the males do. The tusk is actually a single tooth -- narwhals only have two teeth -- that grows out through the whale’s upper lip and can easily reach up to 8 feet in length. The other tooth normally never gets long, though some double-horned narwhals have been seen. The tooth grows in a counter-clockwise spiral and is now known to contain nerves that provide the narwhal with information about his environment.
- University of Washington: Narwhal FAQ
- Messiah College: The Narwhal – Basic Facts
- Harvard University Gazette: Marine Biology Mystery Solved
- University of California San Diego: Voices in the Sea: The Narwhal
- University of Michigan Animal Diversity Web: Narwhal
- Exploratorium Ice Stories: Arctic Whales: Narwhal
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