8 things you didn’t know about narwhals

Known as the unicorn of the sea, take a look at these awesome facts about everyone’s favourite whale!

 

Narwhals begin life with teeth

Although adult narwhal have only four teeth, two of which are beneath the gum line. A developing narwhal foetus has 16 teeth, but these teeth are engulfed by the gums and are not used for chewing as an adult.

Tusk growth isn’t uniform

1 in 500 male narwhals grows two tusks, and 15 per-cent of females grow a single tusk. In many other animals, tusk or horn growth can reflect the health, age, or status of an animal but this doesn’t appear to be the case in here. So it goes to show, you can’t judge a narwhal by its tusk.

 

[DC], Male Narwhal (monodon monoceros) in clear blue ocean water near surface, View from below. --- Image by © Dave Fleetham/Design Pics/Corbis

They are slow swimmers

Although they are big, they certainly are not fast. Narwhals swim at an average pace of 1.7 metres per second, which is 3.8 miles per hour. That’s slower than the walking pace of a human. Although they are incredibly slow, they have stamina in spades. Dubbed as the ‘marathon runners’ of the ocean, they may not be able to make a quick get-away but they could definitely out-swim you.

They are deep divers

Narwhals can dive to depths of 1800 metres (6000 feet) when feeding, and these dives last between 7 and 25 minutes. The physiology making them excellent divers, is also the reason why they are such slow swimmers. Narwhals have the highest percentage of slow twitch muscle fibers within swimming muscles for any marine mammal – giving them a composition close to human endurance runners. Why does this make them excellent divers? Well this type of muscle is great for storing oxygen. Exactly what narwhals need on a long dive.

They take the same journey every year

Narwhals spend their summers off the coast of Somerset Island in Canada, and move to Baffin bay off the coast of Greenland in the winter. This migrant population is made up of 88 000 narwhals.

Their horn is not a horn

The famous tusk is actually not a tusk after all. It’s an enlarged tooth, but not just any old tooth, it has an impressive network of sensory nerves, with as many as 10 million nerve endings inside. Not all narwhals have tusks – some have two and some have none. It can be quite variable. Some can even grow up to ten feet long, giving all the other narwhals tusk envy.

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Narwhal tooth on display in a museum.

We don’t even know what their non-horn is for

Some believe it is used as a weapon for underwater jousting, or perhaps to flaunt like a peacock and attract a mate. Another (more likely) theory is the aforementioned nerve endings can help transform the elongated tooth into an environmental sensor, helping the whale to detect changes in water pressure or temperature.

There are no narwhals in captivity

Several attempts have been made to keep narwhals in captivity throughout the years. However, it seems we just aren’t as good at keeping narwhals as we are at keeping cats, and every single captured narwhal died within several months.

 

 

 

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Image from www.flickr.com/photos/stuutje

 

Photograph credit: Andre Torrez