Found in Arctic waters, the narwhal is related to the bottlenose dolphin, beluga, porpoise and orca. It is easily distinguishable by the sword-like spiralling tusk that grows through the upper lip of the male. The male's tusk can grow up to 8.8 feet in length although the female grows a much smaller tusk. The narwhal grows anywhere between 13 to 20 feet and weighs up to 3500 pounds.
The narwhal travels in pods of two to 10 but has been sighted in groups of 15 to 20, with some reports describing hundreds or thousands of narwhals congregating. It communicates through a system of squeaks, trills and clicks.
While the tusk's purpose is not known, National Geographic theorizes that it is used for mating rituals, either to impress females or attack rival males. Observers have also witnessed males crossing tusks in a friendly or affectionate manner, either as a form of play or a way to clean their tusks.
The narwhal is one of the rarest whale species; its population is estimated at 45,000 to 50,000. Its migratory patterns cause it to travel close to the shore during the summer and live beneath the ice during the winter. Its diet is primarily composed of squid, fish and shrimp.