Improved travel infrastructure has made it possible for more divers to visit the furthest reaches of our planet, including the Arctic Circle, where many fascinating creatures can be encountered. One of the marine mammals sometimes encountered here is the narwhal – a toothed whale closely related to the beluga whale. Nicknamed the Unicorn of the Sea, the narwhal is distinguished by its long, helical tusk, which is actually an elongated left upper canine tooth.
Narwhal Facts
The narwhal isn’t just found in the Canadian Arctic – it also inhabits waters around Greenland, as well as other locales above 65° North latitude. Capable of diving to an astonishing depth of approximately one and one-half kilometers below the surface, the narwhal preys primarily on benthic flatfish, polar and arctic cod, shrimp, and squid.
Narwhals are typically encountered along the edges of ice floes and in summer, they also inhabit ice-free waters, where they rest motionless at or just beneath the surface. During particularly icy winters, they surface through cracks in the ice to breathe, sometimes in large groups.
Male narwhals are an average of four meters long, and females are slightly smaller, with an average length of 3.5 meters long. Adults can weigh anywhere between 800 and 1600 pounds at maturity. Males reach maturity at between 11 and 13 years of age, and females at between 5 and 8 years old. Calves are dark-colored when born, and as they grow, the whales take on a mottled grey and white appearance. The oldest males may lose almost all pigmentation, and can be nearly pure white like their beluga whale cousins.
Narwhals are well-adapted for life in icy oceans; for example, they have no dorsal fins, making it easier for them to surface from under ice floes with less risk of injury. In addition, the narwhal’s neck vertebrae are jointed rather than fused; both of these physical characteristics are shared by beluga whales.
What about that tusk? Decidedly the most fascinating of the narwhal’s physical characteristics, the tusk grows in a spiral pattern through the lip from the left upper jaw. The older the narwhal, the longer the tusk is likely to be; it reaches lengths between 1.5 and 3.1 meters. Approximately one in 500 males possesses two tusks, and some females also grow tusks though they tend to be smaller and less spiral-shaped.
Despite its formidable appearance, the narwhal’s tusk seems to be mostly for show, like a peacock’s tail or a lion’s mane. The tusks are rarely used for fighting, and they’re rarely used as tools for icebreaking or other behavior. In fact, the tusk is extremely sensitive, with thousands of nerve endings. There is only one documented instance of a narwhal using its tusk against another animal; in this case, the broken tip of a narwhal’s tusk was discovered embedded in a beluga’s melon in a manner indicative of a less than friendly encounter.
During the summer, when narwhals congregate, bulls sometimes engage in a behavior called tusking, in which they rub their tusks together as a method of maintaining social hierarchy. Like other whales, they use a series of vocalizations to communicate.
Like other animals in the arctic region, narwhals are threatened by climate change. As are other cetaceans, they are sometimes injured or killed when struck by boats, and they’re a favorite prey animal for polar bears and orcas. When brought into captivity, they tend to die rapidly, but in the wild, they’re believed to live for an average of about fifty years.
Some great places for diving with narwhals include Newfoundland, Hudson Bay, and Labrador, Canada, as well as Greenland, Norway, and Russia. These areas are also well-known for their beluga whales, humpback whales, and other exciting marine life including puffins, seals, and walruses. Though diving with narwhals might sound like a chilly adventure, it’s one you’ll never forget!