“A narwhal's tusk is actually a tooth—usually the upper left canine—that can grow up to 10 feet (3 m) long.”
The narwhal is an Arctic whale famous for the long spiral tusk of males, an overgrown tooth packed with nerve endings. It dives deep beneath sea ice for fish and squid and is listed as Near Threatened.
By An Nguyen · Published · Updated
Monodon monocerosArtiodactylaMonodontidae
Browse narwhal images—from tusks and pods to Arctic sea ice and surfacing behavior.
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A closer look at habitat, diet, behavior, reproduction, and conservation.
The narwhal (Monodon monoceros), nicknamed the "unicorn of the sea," is a medium-sized toothed whale of the high Arctic, instantly known for the long spiral tusk that projects from the head of most males. It spends its whole life in cold, ice-covered water, and together with the beluga it makes up the small whale family Monodontidae. Behind the tusk is an animal finely tuned to hunt in the dark, deep water beneath Arctic pack ice.
The narwhal's "horn" is actually a tooth — an elongated left canine that grows straight out through the upper lip, spiralling counter-clockwise and reaching up to about 10 feet. It is present in nearly all males and roughly 15% of females. Unusually, it is built inside-out, with a porous surface and millions of tiny channels running to nerves at its core, which makes it a sensory organ that may detect changes in salinity and temperature in the surrounding water.
Its role is still debated. Males often "tusk" at the surface — crossing and rubbing tusks — which looks less like combat than a way to size up rivals and settle rank, and possibly to clean the tusk's sensitive surface. How the tusk compares with a true horn is separated out in is a narwhal's tusk really a horn?.
Narwhals are stocky whales, 13 to 20 feet long (not counting the tusk) and 1,760 to 3,500 pounds, with mottled gray skin that pales with age until old animals look nearly white. Two features stand out for polar life. First, they carry an exceptionally thick, blood-rich blubber layer — up to about 40% of body mass — for insulation and energy. Second, they have no dorsal fin, which cuts heat loss and lets them slip along directly beneath sheets of pack ice without a fin catching. Unfused neck vertebrae give them a flexible neck for scanning in tight, cluttered water under the ice.
The narwhal is an Arctic specialist with a circumpolar range confined to the seas off Canada, Greenland, Svalbard, and Russia. Its year follows the ice. In the brief summer it gathers in shallow, ice-free coastal bays and fjords to calve and molt; as autumn ice forms, it migrates offshore to deep wintering grounds over the continental slope, such as Baffin Bay, where it spends up to six months in water that can be 95% covered by pack ice — breathing through narrow, shifting cracks called leads.
Narwhals have no working teeth in the mouth (the tusk plays no part in feeding), so they hunt by suction, drawing whole prey in. The diet is narrow and fatty: mainly Greenland halibut, Arctic and polar cod, and deep-water squid, varying by season.
Reaching that food demands remarkable diving. Narwhals routinely make vertical foraging dives past 5,000 feet (1,500 m) that can last more than 25 minutes, among the deepest of any marine mammal. In the darkness at depth they rely on narrow-beam, high-frequency echolocation clicks to find and target individual fish near the seafloor.
Narwhals live in pods. In summer staging areas these can merge into aggregations of hundreds or thousands, but the core units are smaller maternal groups or male coalitions of about 10 to 20. They stay coordinated through a repertoire of whistles, pulsed calls, and trills that keep the pod together during migration and may carry individual identity — important for animals that travel long distances under ice where sight is limited.
Narwhals have a slow life history with heavy investment in few young. Mating happens offshore in the pack ice in early spring, and after a long gestation of about 14 to 15 months the female gives birth to a single calf during the summer move into warmer coastal water. A newborn is about 5 feet long and over 175 pounds, uniformly gray or brown rather than mottled.
Milk exceptionally rich in fat — over 50% — lets the calf build the blubber it needs fast. It stays dependent for one to two years, learning migration routes and deep-diving skills. Females mature around 6 to 8 years and males later, around 11 to 13, and wild narwhals can live up to about 50 years. They effectively cannot survive in captivity.
The narwhal is listed as Near Threatened, with a global population estimated around 170,000 to 190,000. Its natural predators are orcas and — at breathing holes — polar bears, but the largest pressure is climate change. Shrinking sea ice disrupts the whole cycle: it opens the Arctic to more orcas, shifts the distribution of the narrow range of prey narwhals depend on, and clears the way for shipping, seismic oil exploration, and fishing.
Narwhals are also very sensitive to underwater noise, which can mask their echolocation and calls and cause chronic stress. They remain subject to regulated subsistence hunting by Inuit communities in Canada and Greenland for meat, muktuk, and ivory. Their long-term future depends mainly on curbing greenhouse-gas emissions and protecting key High Arctic waters.
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Artiodactyla
Family
Monodontidae
Genus
Monodon
Species
M. monoceros
A narwhal's tusk is actually a tooth—usually the upper left canine—that can grow up to 10 feet (3 m) long.
The tusk contains up to 10 million nerve endings that may detect changes in water temperature, pressure, and salinity.
Narwhals can dive deeper than 5,000 feet (1,500 m) below the ocean surface to find food.
The name 'narwhal' comes from Old Norse meaning 'corpse whale' because their mottled skin resembles a drowned sailor.
Some narwhals grow two tusks, though this is rare and usually only occurs in males.
Narwhals have no dorsal fin, which helps them swim under sea ice without getting stuck.
Select a question to reveal the answer.
A narwhal is a medium-sized whale that lives in Arctic waters. It is best known for its long spiral tusk, which is actually an elongated tooth that can grow up to 10 feet long.
No. The narwhal's tusk is a tooth—usually the upper left canine—that spirals through the whale's upper lip and keeps growing throughout its life.
Scientists believe the tusk is a sensory organ packed with nerve endings that detect water temperature, pressure, and salinity. Males also use tusks in sparring displays.
Narwhals live in the Arctic Ocean and surrounding seas near Canada, Greenland, Norway, and Russia. They prefer cold, icy waters and spend winters under sea ice.
Narwhals are carnivores that hunt Arctic cod, Greenland halibut, squid, and shrimp. They dive very deep—sometimes over a mile—to find prey.
Narwhals can dive deeper than 5,000 feet (1,500 m) and hold their breath for up to 25 minutes. They are among the deepest-diving marine mammals.
Adult narwhals are typically 13 to 20 feet (4–6 m) long and can weigh up to 3,500 pounds (1,600 kg). The tusk adds several more feet to a male's total length.
Narwhals are listed as Near Threatened. Climate change is melting the sea ice they depend on, and they are hunted in some regions for food and ivory.
Most females do not grow a tusk, or they have a very small one. The long, prominent tusk is mainly a male trait, though some females do develop one.
Orcas are the main predators of narwhals. Polar bears sometimes catch them at breathing holes in sea ice. Greenland sharks and humans also pose threats.
Narwhals can live up to 50 years in the wild. They rarely survive in captivity, as they are highly adapted to the extreme Arctic environment.
Narwhals earn this nickname because their long spiral tusk resembles the horn of a mythical unicorn. Medieval Europeans often sold narwhal tusks as genuine unicorn horns.
Yes, narwhals are carnivores. They hunt Arctic cod, Greenland halibut, squid, and shrimp during deep dives beneath Arctic water and sea ice.
Narwhals have thick blubber, no raised dorsal fin, and strong echolocation. These traits conserve heat, reduce interference beneath ice, and help them navigate and find prey in dark water.
A narwhal has a streamlined whale body, thick blubber, flexible neck vertebrae, and no dorsal fin. In most males, one upper canine grows through the lip into the long spiral tusk.
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