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Dubbed the “unicorns of the sea”, Narwhals are strange and beautiful creatures with a long tusk protruding from their heads. They change color as they age. Newborns are colored blue-gray, juveniles are blue-black and adults are mottled gray. Old narwhals are nearly all-white. They spend their whole lives in the freezing Arctic waters of Canada, Greenland, Norway and Russia.

See the fact file below for more information on the Narwhal or alternatively, you can download our 27-page Narwhal worksheet pack to utilise within the classroom or home environment.

Key Facts & Information

Etymology, Anatomy, and Habitat

Common Name: Narwhal
Scientific Name: Monodon monoceros
Type: Mammals
Diet: Carnivores
Size: 13 to 20 feet
Weight: Up to 1.5 tons
Conservation Status: Near threatened
The narwhal (Monodon monoceros), or narwhale, is derived from the Greek word for “one-tooth” or “one-horn”. It is a medium-sized toothed whale that possesses a large “tusk” from a protruding canine tooth.
The tusk is most commonly found on male narwhals. It is actually an enlarged tooth with sensory capability, having up to 10 million nerve endings inside.
Some narwhals have two tusks, while others have none. The spiraled tusk juts out from the head and can grow as long at 10 feet.
The narwhal is most closely related to the beluga whale.
Males can grow up to 6.2 meters – the average size being 4.7 meters – and weigh about 1,600 kg.
Females are smaller compared to male narwhals, with an average size of 4 meters and a maximum size of 5.1 meters and weigh around 900 kg.
A newborn calf is about 1.6 meters long and weighs about 80 kilograms.
A narwhal has a deep layer of fat, or blubber, about 10 cm thick, which comprises one-third of the animal’s weight and acts as insulation in the cold Arctic waters.
Narwhals have a mottled black and white, grey or brownish back, but the rest of the body is mainly white.
Newborn narwhal calves are pale grey to light brown, developing the adult darker coloration at about four years old. As these narwhals grow older, they will become progressively pale again.
The narwhal’s coloring gives researchers an idea about how old an individual is. Some may live up to 100 years, but most live to be 60 years of age.
Their most striking feature is undoubtedly their tusk. This long spiraled upper canine tooth is one of the two teeth narwhals have that grow out from the animal’s upper jaw and can measure up to 3 meters and weigh 10 kg.
The function of the tusk remains a mystery, but several hypotheses have been proposed. Many experts believe that it is a secondary sexual character, similar to deer antlers. Thus, the length of the tusk may indicate social rank through dominant hierarchies and assist in competition for access to females.
The tusk grows throughout a male’s lifespan but slows down with age.
Habitat requirements of narwhals are little known. The fact that they remain year-round in the Arctic waters, which are covered by sea ice for most of the year, makes the study of narwhal habitat somewhat difficult.
Narwhals generally spend winters – from November to April – in very deep, ice-covered waters where upwelling currents bring extra nutrients to the ecosystem. There, they spend much of their time in deep dives in search of food.
In July and August, narwhals disperse over a vast region farther north, in the Canadian High Arctic archipelago. These Narwhals group together in coastal areas, in bays, island passages and fjords with access to deep open waters.

Behavioral Traits and Conservation Status

During their migration, hundreds, even thousands, of individuals may be seen traveling together, but otherwise, narwhals tend to remain in smaller groups – or social units – of about three to eight individuals once in their summering or wintering areas.
These groups often comprise of same-sex and similar-aged individuals as well as mixed age-sex groups.
Even though narwhals are capable of traveling for a kilometer or more between breathing breaks, they need cracks in the ice to access air.
Narwhals are fully equipped to deal with long periods without oxygen in a high-pressure environment. They have been known to dive to 1 500 meters deep, with dives lasting 25 to 30 minutes.
Narwhals blood and muscles can hold more oxygen than most mammals, even many other whales, and they rely on their high number of blood vessels between their heart and lungs.
Between dives, narwhals quietly spend long periods of time lying at the surface – a behavior called “logging” – while they breathe heavily to restore their oxygen in preparation for the next dive.
Also, since very little light shines in the depths under the ice, narwhals use sound to investigate their environment. This process is called echolocation, which is also used by bats at night.
The whales get information about their surroundings by emitting clicks and knocking sounds that bounce off objects in the water. The melon, a fatty bump on their forehead, is used to focus and amplify these sounds. The echoes are captured by their hollow lower jaw and transmitted to their ears. Their brains then analyze these signals to get an idea of what’s around them and its distance. This process works like a sonar.
Narwhals are gregarious, they live in groups and communicate with each other by using whistles, squeaky hinge-like sounds and many other noises, which they produce by controlling the air passages near their blowholes.
When socializing, males have been shown to use greater “vocabulary”, or a larger range of sounds, than females.
Recent data has estimated the Baffin Bay population to be between 60,000 and 80,000 individuals, while the Hudson population is comprised of about 5,000 animals. The number of individuals in the East Greenland population is about 10,000. These numbers demonstrate that the narwhal is not rare nor at risk, unlike what is commonly thought. Even so, there are potential threats to this highly specialized species.
Only Inuit may hunt narwhal for subsistence, and they do so within a quota, or maximum number of catches. Inuit hunters need an export permit to sell tusks internationally.
The narwhal is hunted because of its vitamin C-rich skin for a meal called “maqtaq” in Inuktitut, but also because of its tusk. Narwhal tusks are valuable items on national and international markets.
Greenland instituted a ban in 2006 of all narwhal product exports, but before this ban, the only tusks that could be purchased in the European Union were gathered through Greenland Inuit hunts. An estimated 400 to 600 narwhals are hunted each year in Canada, and more studies are needed to know if this level of hunting is sustainable.
Ocean contaminants might also be a threat to the species. Heavy metals and other pollutants like pesticides tend to accumulate in the narwhals’ blubber and liver. This could cause health issues for the narwhal and even to humans that consume it.
Climate change and its impact on sea ice and water currents could be detrimental to the narwhal due to the whale’s close association with ice. Both the disappearance and the increase of ice could have an impact on the species.
It is important to have the best information about the narwhal. The more we know, the more efficient our efforts will be towards the conservation of the “unicorn of the sea”.

Narwhal Worksheets

This is a fantastic bundle which includes everything you need to know about Narwhal across 27 in-depth pages. These are ready-to-use Narwhal worksheets that are perfect for teaching students about the dubbed the “unicorns of the sea”, Narwhals which are strange and beautiful creatures with a long tusk protruding from their heads. They change color as they age. Newborns are colored blue-gray, juveniles are blue-black and adults are mottled gray. Old narwhals are nearly all-white. They spend their whole lives in the freezing Arctic waters of Canada, Greenland, Norway and Russia.