Marianne Marcoux, a research scientist for Fisheries and Oceans Canada, noted that drones have been an innovative tool for studying these elusive animals.
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 neighboring 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. 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.
Although this hasn't been reported in reality, perhaps it could function as a weapon? Narwhals have rarely been observed using their tusk to aggressively fight other narwhals and the act of "tusking" between male narwhals seems to be a passive interaction.
The tusk is also too long and slender to be functional for chipping away at sea ice and it would be useless as a spear as the removal of speared items from the tusk would prove tough. As the tusk lacks an enamel covering and with a porous outer surface means that it is exposed to the narwhal's environment. As such the tusk could be sensitive to temperature and chemical cues. The centre of the tusk is made up of pulp, just like our teeth, which contains nerve endings, allowing for the relay of messages to the brain.
New research has suggested that the tusk may be a sensory organ. It was shown that when a narwhal is exposed to water of different salt levels there is a noticeable change to its heart rate, possibly identifying a reaction that could help narwhals to locate fish, find mates or predict when the sea is freezing, preventing entrapment.
Size: 13 to 20 feet. Weight: 1. Size relative to a bus:. Near threatened. Least Concern Extinct. Current Population Trend: Unknown. Share Tweet Email. Go Further. Animals Wild Cities This wild African cat has adapted to life in a big city. Animals This frog mysteriously re-evolved a full set of teeth. Animals Wild Cities Wild parakeets have taken a liking to London. Animals Wild Cities Morocco has 3 million stray dogs.
Scientists have long thought that the tusk was used for fighting, or as visual display of male dominance to attract females.
Some researchers have also theorized that narwhals might use their tusk to break through sea ice or fend off other predators, such as polar bears and orca whales. The tusk is not just an extension of tooth-like material. It is filled with sensitive pulp for nearly the entire length. Narwhals may use their tusks to detect temperature, water pressure, particle gradients, and motion.
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