It sounds like a mystery pulled straight from science fiction: reports of a pinging noise emanating from the bottom of the sea; local wildlife spooked; the military scrambles an aircraft in the remote Arctic to investigate.
But this isn't a missing "X-Files" script, this actually happened high in the Canadian Arctic and, so far, there's no satisfactory explanation as to what's going on.
For the last few months, local (mainly Inuit) populations around Canada's northeastern Nunavut Territory have reported that the waters in a once-fertile hunting ground has been strangely devoid of sea mammals. The large territory is home to around 31,000 people who regularly hunt seals, caribou and whales in the Hecla and Fury Strait. According to ScienceAlert, this is a prime location as it's an open area of water surrounded by ice known as a "polynya," which sea mammals use as feeding grounds.
The apparent lack of animals this summer has coincided with reports of a mysterious sound coming from the sea floor and many are pointing to the anomaly as being the cause. The noise - described as a "pinging," "humming," or "beeping" - has been heard for several months and is now being taken seriously by the Canadian government.
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"The Department of National Defence has been informed of the strange noises emanating in the Fury and Hecla Strait area, and the Canadian Armed Forces are taking the appropriate steps to actively investigate the situation," a government official said in a statement.
Among the measures taken, a CP-140 Aurora aircraft was dispatched to the region to seek out "acoustic anomalies," but nothing out of the ordinary was found.
"The (aircraft) crew did not detect any surface or sub-surface contacts," the Canadian military told the BBC. "The only thing the crew did observe were two pods of whales and six walruses in the area of interest."
According to a group of boaters on a private yacht who passed through the area, the sound could be clearly heard through the vessel's hull, but further evidence is apparently hard to come by.
As with any mystery, hypotheses as to the strange noise's source are rich and varied. One idea is that it could be evidence of a mining company in the area conducting sonar surveys of the sea floor, though no permits have been approved and local companies deny they're carrying out such work. Another theory points the finger at the conservation group Greenpeace, who have a history in the region having opposed the Inuit seal hunt in the 1970s and 1980s.
A Greenpeace spokewoman, however, told CBC News that they have nothing to do with the mysterious noise and that they wouldn't drop a sonar device in the waters to scare away wildlife. "Not only would we not do anything to harm marine life, but we very much respect the right of Inuit to hunt and would definitely not want to impact that in any way," said Farrah Khan.
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Of course, the very fact the noise is being described as a "pinging" hints at submarine activity. Military analyst Tyler Rogoway points out that, although unlikely, submarines could be traveling through the region. Though deep in Canadian territory, as climate change has increased the frequency at which the Hecla and Fury Strait is ice-free, it's conceivable that the passage could be eyed as a route into the previously hard-to-navigate waterways. There is no evidence to suggest this is the case, however.
Officials agree that, for now, the source of these reported noises is a mystery. But it's worth remembering that correlation is not the same as causation; the coincidence of a mystery pinging in Arctic seas isn't necessarily causing the apparent reduction in sea mammal wildlife in Canada's northeastern Nunavut Territory. It could just be that the two are happening at the same time and have no relationship with one another. As climate change is accelerating its impact on Arctic regions, it's more likely that marine animals are migrating farther afield to look for feeding grounds and the local populous is blaming scattered reports of a strange noise as being the culprit.
As with the bizarre ocean "Bloop" that captivated the world when it was recorded by Pacific Ocean hydrophones in 1997, the source of this Arctic "Ping" will likely be found - it could be artificial or it could be natural. The Bloop was found to be (probably) generated by ice-quakes in calving glaciers, could the Canadian Ping have a similar cause? Who knows, but science will, eventually, zero-in on an explanation.
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