Wildlife Wednesday Species Spotlight Program
While social distancing requires us to temporarily suspend our monthly Wildlife Wednesday seminars, that doesn’t mean the learning has to stop.
Enrich your wildlife knowledge by following along with our weekly Wildlife Wednesday Species Spotlight. Each week during the Covid-19 pandemic, we will highlight a new Alaskan species, provide fun and interesting facts about the species, and for a bit of destress time, an image of that animal to color (great for kids and adults alike!). Play along with our Trivia Tuesday on our Facebook page to get a hint on the week’s species. Tag Alaska Wildlife Alliance when you upload your outdoor photos of the species and/or your finished coloring sheet!
Narwhal Fact Sheet
Narwhals breathing in a lead at the surface | Photo courtesy of NOAA
Scientific and common names
Monodon monoceros; narwhal; unicorn of the sea
General Description
Narwhals are toothed whales averaging between 16-17.5 feet long as adults, and can weigh over 4,000 lbs (2 tons!). Males are typically larger than females. Like their closest relative, the beluga whale, narwhals lack a dorsal fin. Their bodies are covered with dark gray and black spots on their back fading to a light cream-colored underside. They are often called the “unicorns of the sea” because in males, one of their two teeth grows into a long tusk up to 9 feet in length. This tusk always grows in a counter-clockwise spiral (as the animal sees it) and grows continuously, replacing wear. While the exact purpose of the tusk is unknown, it has been speculated to be used for courtship, fighting and foraging. Like other toothed whales, narwhals have evolved complex and sophisticated echolocation systems using sound to navigate their environment.
Centuries ago, the rich spent fortunes to obtain unicorn horns, which were often narwhal tusks brought back from the Arctic. In An account of the Arctic regions with a history and description of the northern whale-fishery, published by W. Scoresby in 1820, the narwhal is labeled as “Male Narwhal or Unicorn.” Herman Melville devoted a chapter to the narwhal in his American novel Moby Dick, in which he also referred to the narwhal as the “Unicorn whale.” Cited from The Narwhal's Tale: Surviving Sea Ice Change
Range
Narwhals reside in waters of the Arctic, ranging from northeastern Canada, northern Greenland, Svalbard, and waters of northern Russia as far east as the East Siberian Sea. Some narwhals have been recorded in the Chukchi and Bering seas as far south as the Alaska Peninsula and Commander Islands, as well as Newfoundland, the British Isles, Germany, and the Netherlands in the east; animals in these areas are considered “vagrants” since narwhals do not reside in these areas seasonally or year-round. The quality of ice habitats, especially areas of open water and the density of pack ice, seems to be a key aspect of habitat selection. Most sightings of narwhals in Alaska are east of Point Barrow. In summer they prefer deep coastal waters for calving and feeding, and transition in the fall/winter to waters ranging from 1000 meters to 5000 meters (over 3 miles!) deep.
The frequent (solid) and rare (striped) occurrence of narwhal populations
Life History
Narwhals generally, but not always, breed in the spring, with gestation lasting between 14 and 15.3 months. At birth, narwhals are dark bluish gray, weigh about 175 lbs, and are about 5 ft long. Calves nurse for one to two years. Females mature between ages 4 and 9, whereas males mature between ages 11 and 16. Females give birth to their first calf when they are between the ages of 7 and 13. The oldest narwhals may reach 50 years old, but most have a lifespan of less than 30 years.
Diet
Narwhals primarily feed on fish, such as Arctic cod and turbot (a species of flatfish), and invertebrates, such as squid, octopus and crustaceans. Since narwhals only have two teeth, which usually do not erupt from the gumline (except for the tusk in males, and very rarely, females), they swallow their food whole without chewing. Some narwhals use their tusk during foraging, but not to spear their food – they give their prey a quick hard tap with the tusk to temporarily stun the prey before sucking it into their mouth.
Threats & Concerns
Narwhals are dependent upon ice habitats, and extensively use sound to navigate their environment. The Arctic has been warming at a much faster rate than the rest of the world, and as the Arctic warms there will be changes in the ice – it will be thinner, form later, melt earlier, and be less predictable – and ocean currents could change which could result in changes in distribution and density of narwhal prey. A warmer Arctic can also lead to increased shipping and development (which adds noise to their environment, and increases the risk of pollution and ship strikes), and could lead to the introduction of novel species to Arctic waters (such as predators and diseases for which narwhals have no defense). In the US, there are no fisheries operating in the range of the narwhal, nor are narwhal hunted for subsistence purposes.
Narwhals are one of the most mysterious ocean species, but as their icy home melts, it’s becoming more deadly to the narwhals. Learn about the impacts of climate change on narwhals.
Fun Facts
A narwhal’s tusk is actually an inside-out tooth (usually its right tooth!), soft on the outside and hard on the inside, with a flexible tip, and full of nerves making it a highly sensitive organ.
The earliest record of a narwhal in Alaska dates back to 1874.
Although rare, it is believed that narwhals and belugas can breed to produce a hybrid. Hmm, would that be called a narluga or a beluwhal?
The GREMM research team was filming a group of belugas when they realized a narwhal was amongst them! Was this the same individual as the one observed in 2016 and 2017? After photographing the vagrant as well as his companions from both sides, researchers were able to confirm that it was indeed the same narwhal! Learn more about the adopted narwhal here!
