Once said to possess magic powers, narwhal tusks were sold as unicorn horns centuries ago, and still today some mystique surrounds the overgrown tooth protruding from this unique whale's head. Scientists have never been able to pin down the exact purpose it serves, but have now captured the first-ever video evidence of it being used as a hunting tool, helping to unravel some of the mystery.

All kinds of theories have emerged regarding the use of the narwhal's tusk. The whales, which feed on squid, cod and shrimp in the Arctic, grow tusks up to 10 ft long (3 m) with up to 10 million nerve endings inside. But why? To bash through ice? Transmit sounds? To spear fish?

If you came here looking for dramatic footage of a whale impaling a fish and bursting triumphantly through the water's surface to show off its catch, you may be a little disappointed. Using drones to study narwhal behavior in far northern Canada, scientists have, however, seen narwhals using their tusks to capture their prey, though it is more of a subtle swipe, intended to stun the fish before scooping it up in their mouths.

The evidence, gathered by various research groups including the World Wildlife Fund Canada and Fisheries and Oceans Canada, is important all the same. The scientists say learning more about narwhals in the face of changing Arctic conditions will help conservation efforts moving forward.

"This footage, while also stunning to watch, will play a significant role in the future of narwhal conservation," says David Miller, President and CEO of WWF-Canada. "As the Arctic warms and development pressure increases, it will be important to understand how narwhal are using their habitat during their annual migration. With this information in hand, we can work to minimize the effects of human activities on narwhal."

Check out the footage below.

Source: WWF