Narwhal Tusk Facts: Did You Know?

Yes, narwhals are real and a tusked narwhal can feel fantastical to see in person. Narwhal whales can sometimes seem like a myth and people have wondered for ages just why narwhal even have a tusk.

It’s wild how much a tusk can set an animal apart from others. It makes them stand out and creates a sense of wonder that fascinates people all over the world.

Elephants have tusks to push brush out of their way, rhinos have a horn to defend themselves, and even in the Arctic walrus have teeth to maintain breathing holes in the ice during the frozen winter. But why does a narwhal have a tusk?

Profile: The Narwhal

COMMON NAME: Narwhal

SCIENTIFIC NAME: Monodon monoceros

TYPE: Mammals

DIET: Carnivore

SIZE: 13 – 18 ft /3.95 – 5.5 m

Male WEIGHT: 1,600 kg / 3,500 lb

Female WEIGHT: 1,000 kg / 2,200 lb

Life span: 50 y/o

The narwhal is most closely related to beluga whales and they are the two species that comprise the only members of the family Monodontidae.

Narwhals have a mottled pattern, with blackish-brown markings over a white background. They are darkest when they are younger and become whiter as they get older.

The tail flukes, the two wings that form the tail flipper, of males have front edges that are more concave and lack a sweep-back shape found in females. This is thought to be an adaptation to overcome the drag caused by the tusk.

Narwhal Tusks: Did You Know?

Did you know that a narwhal tusk is actually a tooth?

In fact, the scientific name is Monodon Monoceros which comes from the Greek meaning, “one-tooth one-horn.”

The tusk is a canine tooth that protrudes through the lip and continuously grows throughout their lives reaching up to 10 ft / 3.5 m.

The narwhal tooth is the only straight tusk in the world, all other tusks are known to curve.

While the tusk doesn’t curve, but it does form a spiral. It will always be a left-turning helix spiral. Even when a second tusk grows, both tusks spiral to the left.

All narwhals have two canine teeth that can grow into their tusk, but generally, it’s the upper left tooth that grows.

The tusk grows in most males and only about 15% of females. And about one in 500 males grow two tusks, and only one female has been recorded with two tusks.

Why Do They Have Them?

If only males tend to grow them, what are they for?

It is still unclear the purpose of the tusk. They aren’t used for dueling and they don’t spear food with them. If it was an evolutionary trait for hunting and not dueling then more females would have them.

We know it is a tooth but its composition is inverted.

While there is normally a hard coating of enamel, dentin, and cementum that shields the sensitive nerves, in fact, the narwhal tusk has nerves on the outside with the dense material on the inside of the hollow tusk and is used as a sensory organ.

The tusk has millions of tiny holes and nerve endings on the surface of the tusk. Seawater enters tiny holes in the tusk that channels the water into a “sensory centre” at the base of the tusk. These nerve endings send valuable information to the brain giving it information on the water around them.

These external stimuli provide vital knowledge for these Arctic whales. It’s believed that they can sense chemical changes in the water like the salt levels, temperatures, and water pressure while they’re migrating. And it’s also believed that they can sense chemicals released by potential mates.

Now, they have been used for practical uses like the rare practice of tapping a fish to stun it when they eat. But primarily it is believed to be a guiding feature. That means that when they gently do rub tusks together, it’s possible that they are transferring important information about the water’s environment.

One of the more simplistic reasons for the tusk could be that it is something of a flashy gender-based characteristic, like a lion’s mane. The idea is that it offers little function but may set certain narwhals apart from others for mating rights. But the question persists, why don’t females grow them more often?

We continue to be fascinated by this remarkable animal. The mystery of the tusk draws people to this Arctic whale and has been a source of countless folklores and legends like the unicorn. A tusk has even been used to defend London Bridge! This mysterious tooth is one of nature’s more intriguing features.

There is nothing more incredible than seeing these beautiful whales burst above the water’s surface. Capturing a photo of a tusked narwhal fulfills any Arctic bucket list. And with 75% of the world’s narwhal population migrating into the Canadian Arctic there is no better place to see them!