Narwhal (Monodon monoceros) is a medium-sized Arctic toothed whale famed for the long spiraled tusk that gives it the nickname "unicorn of the sea." Found primarily in Arctic waters, narwhals live in coastal and offshore areas and are most often sighted in summer when they move into bays and fjords. For more general information see this resource.

Physical characteristics

Narwhals have robust, mottled gray bodies that darken with age. They lack a dorsal fin, an adaptation to swimming beneath sea ice. Adult lengths typically place them between small whale and large dolphin sizes. The species shows clear sexual dimorphism: males commonly develop a single long tusk — an elongated upper left canine — while females rarely do. Tusk length in males can reach about two to three meters in well-documented examples.

Tusk: form and function

The tusk is a distinctive, left-side tooth that spirals outward and projects forward. Historically surrounded by myth, modern research suggests multiple functions: a sensory organ rich in nerves that can detect changes in water temperature or salinity, a tool for social interaction and dominance displays, and possibly a secondary role in feeding. Its precise uses vary and remain an active field of study.

Behavior and ecology

Narwhals are social animals that form pods ranging from a few individuals to larger aggregations. They feed on fish, squid and benthic invertebrates, diving deep to reach prey on continental shelves. Narwhals use echolocation to navigate and hunt under ice. Seasonal migrations take them between offshore wintering grounds and summer coastal areas, often following shifting ice edges.

Human interactions and conservation

Indigenous Arctic peoples have hunted narwhals for subsistence for centuries; the species also has a role in local cultures and oral traditions. Modern threats include climate change, loss of sea ice, industrial activity, and noise disturbance. The narwhal is monitored by conservation organizations and subject to management aimed at balancing traditional use with population protection.

Notable facts and distinctions

  • Scientific name Monodon monoceros refers to its "one-tooth, one-horn" appearance.
  • Often called the "unicorn of the sea" because of the tusk.
  • Can be confused with the beluga, but narwhals lack the beluga's white coloration and dorsal prominence.
  • Predators include orca and polar bears when calves are at surface or near ice edges.