If you’ve ever wished Unicorns were real, you can find a very close second in Narwhals! With single tusks that make them a bit of a natural anomaly, these whales find a home in the icy waters of the Arctic Ocean.
General Information
What are Narwhals?
Narwhals are a species of whale that are defined by their large tusks. Dubbed the “Unicorn of the Sea,” they are one of two types of whale that spend their lives in Arctic waters, next to Beluga Whales.
Narwhals do not vary in anatomy from most other whale species, outside of their lack of dorsal fin (also a trait found in Belugas) and tusks, which we will discuss later on. Below you will find a breakdown of a Narwhal’s anatomy.
Flippers & Flukes
Flippers, found at either side of the Narwhal are used to help steer their bodies through the water.
Flukes, found on the tail, are meant to help propel the animal through the water.
Blowhole
A nostril located at the top of the head of all whales and porpoises. Narwhals need to surface every so often to take a breath. They can hold their breath for up to 25 minutes.
Blubber
Blubber is a thick layer of fat, or adipose tissue, that is formed just beneath the skin of all marine mammals. It is formed throughout the body, with the exception of the fins, flukes, and flippers. Blubber is very important for these mammals, as they store energy, insulate heat, and increases their buoyancy.
Pigment
Narwhals can range from a white to dark grey color with pigmented spots. These spots develop as an individual grows and can assist with identification and camouflage.
Teeth
Believe it or not, these carnivores are only equip with two teeth! One is located inside of the upper lip; and the other is actually that infamous tusk!
Tusk
Now let’s talk about this infamous tusk. While there is much speculation as to the composition and function, the narwhal tusk is actually one of a pair of teeth. Growing up to 10 ft (3 m) in or more in length, they’re primarily exhibited in males. This spiraled, ivory tusk is comprised of thousands of sensory nerve endings, much like human teeth, that can detect subtle changes in pressure, temperature, and particles in the water column. Unlike humans (or any other animals), though, this giant tooth’s inner-core nerve system connects directly to the outside; creating a direct link from the narwhal’s central nervous system to the outside world. Truly, these tusks are an evolutionary spectacle.
Understanding the function of these tusks is even more of a mystery than the tusks, themselves. It wasn’t until recently that scientists had a better idea of what these great appendages.
The automatic idea when you first see these tusks is that they’re probably used to fight and assert dominance. While there is little to no recorded observation of narwhals fighting, it’s not out of the question. Individuals have been found with broken tusks, and other with bits of foreign tusk embedded in their blubber. Leaving the idea that there is some form of sizing up and fighting for dominance.
While this seems like a reasonable and educated guess to the tusk’s function, through observation we have learned that they can be used for so much more. For one, it is believed that those sensory nerve endings assist with the narwhal’s ability to use echolocation to travel – which is a skill most porpoises have. It is also believed that, based on the sheer size of them, the tusks were developed as a form of sexual selection. Similar to male peacocks and their feathers, sexually selected traits are those which energy is put towards in order to attract mates.
Perhaps the most shocking function of these tusks that scientists have recently discovered through drone footage, is using the tusks to stun prey. Now the misconception is that those tusks are used to “skewer” their prey – however this would be almost impossible as it would require impeccable aiming and forward momentum in order to penetrate a relatively small prey item. It makes far more sense and uses less energy for the narwhal to create a sort of vacuum with their mouths; where they can devour their prey as it’s stunned. Check out this drone footage below.
Let’s Talk Behavior
Now that we know what makes a Narwhal a Narwhal, we can discuss what kind of behaviors they exhibit. They are very social animals, often viewed travelling in pods of 10-20; and sometimes even into the hundreds! Living in cold Arctic waters, these pods may travel throughout a given area, but have not been observed as migratory.
Every animal needs to eat, right? Narwhals enjoy a variety of fish species, squid, and shrimp. They use those tusks to temporarily stun their prey, and then create a sort of vacuum suction with their mouths to pull their immobile pray in to swallow whole. They have been observed to feed both on the surface and by diving deep into the water column.
As far as mating behaviors; male narwhals, on average, reach sexual maturity around 8-9 years of age, while females mature at 4-7 years. Reproducing in 3 year intervals, the mating season is typically exhibited in the Spring, with young being born the following summer (a 15 month gestation period!). As mentioned earlier, it is believed that sexual selection is a major function of the narwhal’s tusks.
Threats and Concerns
Narwhals only have one animal predator – Orcas (Killer Whales). Unfortunately, this does not mean that they have little to fear. Their two biggest predators throughout history involve humans and climate change.
Like elephants, narwhals have been subject to poaching for their tusks. Narwhals are believed to be the origin of Unicorn lore – so humans have hunted their ivory tusks in attempt to make a profit. Starting in the mid 1600s, the tusks were harvested for medicinal purposes. One was even known to be a prized possession of Queen Elizabeth I.
Narwhals also proved very useful to Eskimos. Their meat was used to feed sled dogs, skin was known to be rich in vitamins, and blubber was used for warmth.
While it seems that narwhals are very useful to humans in many ways, unfortunately humans have caused greater issues to their existence. Over 1,000 narwhals are known to be killed every year between Canada and Greenland alone. They live in areas that are subject to heavy mining and drilling practices. Scientists are starting to see high traces of metal in narwhal tissues and oil leaching contaminates the waters, quickly making them unsafe to live. With these practices come heavy noise pollution, which can affect an animal’s senses (especially considering how sound travels through water).
Narwhals are also very sensitive to changes in water quality. Remember all those sensory nerve endings in their tusks? They can detect the most subtle of changes in temperature and pressure. Climate change is causing the Arctic climate to grow warmer and ice caps are melting. This takes a severe toll on the narwhal’s environment. As these areas change, they search for new areas. Sometimes pods could even get stuck between fallen glaciers and die. It’s truly terrible.
Why Should We Care?
Narwhals are Keystone Species.
Keystone species are those which the survival of the surrounding environment largely depends on. The removal of a keystone species could mean devastation to an environment. Without Narwhals, the entire Arctic environment is at risk of collapse. So while their populations are not necessarily a concern right now, it is pertinent that we do our best to maintain their populations.
How can I help?
A List of Relevant Conservation Efforts
Sources
- Unicorn of the Sea: Narwhal Facts. (n.d.). Retrieved June 01, 2020, from https://www.worldwildlife.org/stories/unicorn-of-the-sea-narwhal-facts
- Narwhal. (2020, March 31). Retrieved June 01, 2020, from https://www.nationalgeographic.com/animals/mammals/n/narwhal/
- Narwhal: Unicorn of the Sea. (2020, June 03). Retrieved June 01, 2020, from https://us.whales.org/whales-dolphins/species-guide/narwhal/
- Hall, D. (2018, May 08). Why a Tusk? The real-life unicorns of the sea and the tusks that make them famous. Retrieved June 02, 2020, from https://ocean.si.edu/ocean-life/marine-mammals/why-tusk-real-life-unicorns-sea-and-tusks-make-them-famous
- Deamer, K. (2017, May 23). Narwhals Use Tusks to Stun Prey, Drone Footage Reveals. Retrieved June 01, 2020, from https://www.livescience.com/59225-narwhals-use-tusks-for-fishing.html
- National Marine Mammal Laboratory. (2006, August 21). National Marine Mammal Laboratory. Retrieved June 02, 2020, from https://www.afsc.noaa.gov/nmml/education/cetaceans/narwhals.php
- Gorter, U. (2017). Narwhal. Retrieved June 02, 2020, from https://www.acsonline.org/narwhal