Scientists have long speculated on what narwhal tusks are for. Video footage now shows how narwhals use their tusks in action.
Narwhals are notoriously skittish, which is why there haven't been definitive answers on what the tusks are for. Observing narwhals can be difficult because of their skittishness, and also because they don't leap through the surface like other whales. They also live in remote places that can be difficult to get to.
Known as the “unicorns of the sea”, narwhals have long, pointed tusks protruding from their faces. These tusks look like the mythical unicorn's horn, hence the fanciful nickname. Tusks are actually teeth that can grow to lengths of up to three meters. Tusks are common in male narwhals, but only a small percentage of females grow tusks.
Scientists have had a number of theories on what narwhal tusks are for. Some have postulated that narwhals use their tusks as ice picks. Others have said that tusks come in handy when males are fighting over a mate, while others have said that tusks may be a tool for echolocation. While these theories may actually be true, we don't know for sure just yet.
We do, however, know of one tusk function for sure.
A drone managed to capture footage of narwhals using their tusks in Tremblay Sound, Nunavut, Canada. The footage shows narwhals using their tusks to stun and immobilize Arctic cod. The narwhals quickly tapped the cod with their tusks, stunning the fish. Stunned fish make for easier prey. The video shows how narwhals stun their prey, then approach them and suction them whole into their mouths. The fish offer no resistance.
Researchers say that narwhal tusks may also be useful as sensory organs. Tusks have thousands of nerve endings that can help narwhals get a better sense of their surroundings. With the use of drones, which can capture footage of narwhals without disturbing them, we may find out more about narwhal behavior.
The video footage was significant for a reason other than the discovery of how narwhals use their tusks. Because of the footage, scientists discovered that narwhals feed in the waters they live in during the summer. Scientists previously thought that narwhals only fed in the waters they live in during the winter.
This discovery can aid scientists in conservation efforts. If scientists can find out where narwhals feed and have their calves, conservation can focus on those regions as well as the routes narwhals take when they migrate.
Like many animal species on Earth, narwhals face a lot of threats to their survival. One of these threats is industrial development. Mining and increasing tourist activity take place in narwhal habitats. Thus, shipping vessels have a significant chance of running over a narwhal. These vessels produce underwater noise that can disrupt narwhal communications and echolocation.
If researchers can map out the narwhals' migration routes and habitats, the information can help the Canadian government set up protected areas. Ships can also take new routes to minimize the impact on narwhal populations.
Finding out what narwhal tusks are for can open up avenues towards keeping narwhal populations safe. Hopefully, narwhals will eventually be able to whack fish over the head and eat in peace.
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