The unicorn of the sea just got a little less mysterious.
Until now, how narwhals used their long tusks had been subject to much speculation by scientists.
Behaviour captured for the first time on camera shows narwhals using the long tusks protruding from their heads to stun Arctic cod by hitting them, using jagged, quick movements. This behaviour immobilises the fish, making them easier to prey upon.
MYSTERY BEHIND NARWHAL'S ICONIC TUSKS REVEALED Video shows how narwhals use their iconic tusks to hunt fish. Filmed near Nunavut, Canada, a narwhal can be seen tapping a fish with its tusk.
The footage was shot by two drones in Tremblay Sound, Nunavat, in Canada's far Northeastern regions by Adam Ravetch for the World Wildlife Fund Canada and researchers from Fisheries and Oceans Canada.
Brandon Laforest, a senior specialist of Arctic species and ecosystems with WWF-Canada, explained why narwhals have been such a mysterious species.
"They don't jump like other whales. They are also notoriously skittish," said Laforest. "This is an entirely new observation of how the tusk is used."
Laforest, working with officials from the Canadian government, spent time camped in the narwhal's winter habitat. Because of the remote regions in which narwhals live, visual confirmation of their behaviour has been difficult to ascertain.
Marianne Marcoux, a research scientist for Fisheries and Oceans Canada, noted that drones have been an innovative tool for studying these elusive animals.
"Drones are very exciting, we can see things we couldn't see before," said Marcoux. Previous aerial observations were conducted by small planes that often provided an incomplete view or frightened the animals.
Three-quarters of the world's population can be found in neighbouring Lancaster Sound, which is being considered by the Canadian government for a protected area.
While the footage confirms one theory of how narwhals use their tusks, they may be used for other purposes as well, such as for ice picks, weapons, sexual selection, or as a tool for echolocation. Laforest, however, thinks they may be especially important as sensory organs. Their tusks are covered in thousands of nerve endings and pores that help narwhals sense the environment around them.
"They can feel their surroundings similar to how a human's broken tooth would have feeling," said Marcoux.
The tusk is a left canine tooth protruding from the heads of males and can grow as long as nine feet. The right canine stays embedded, and no other teeth protrude from the inside of their mouths; narwhals instead use suction to swallow their prey whole.
The new footage is also significant for conservation efforts because it shows that narwhals feed in the waters in their summer waters. Scientists previously believed they fed exclusively in their winter waters around the southern portion of Baffin Island. Identifying the key regions that narwhals depend on for feeding and calving can help conservationists better preserve their environment and migratory routes.
One of the biggest threats narwhals face is industrial development. As mineral extraction and tourism increases in their habitats, they face a greater likelihood of being struck by shipping vessels. Underwater noise from this development also interferes with their ability to communicate.
Because 90 percent of the world's narwhal's can be found in Canadian waters, Laforest stressed the importance of Canadian federal research to identify protected areas and create shipping routes that cause the least amount of disturbance.
Climate changes also may impact the species. They are one of the only animals whose food web is completely dependent upon sea ice, and thus uniquely susceptible to warming waters.
Threats to narwhals also impact the northern Inuit community, which depend on the animals for food and crafts that support their livelihoods.
Next up for the researchers is helping pinpoint critical narwhal calving areas, which may further aid plans to protect them.