The idea of gushing whirlpools so large and strong that they could sink a boat might sound like tall tale but there is some nugget of truth to these legends. Whirlpools can be small and short-lived but the most powerful – known as maelstroms – can be dangerously strong.
Maelstroms are created when strong tidal currents collide or are influenced by underwater landscapes. As the topography forces the water in one direction or another, it can create epic whirlpools.
There are several famous examples. The Maelstrom of Saltstraumen in Norway has currents that can reach 25 miles an hour. The whirlpool appears four times a day and is most spectacular in the days around a full or new moon. During every tidal cycle (of around six hours), 400 million cubic metres of water flow through the maelstrom.
The sloshing water at the 76-metre Old Sow – located between Deer Island, New Brunswick in Canada and Moose Island in Maine, USA – grunts and gulps like hungry pigs and the smaller whirlpools that are created nearby are known as its piglets.
The Cambridge Dictionary defines them as “an area of water that moves with a very strong circular movement and sucks in anything that goes past.” As this suggests, these phenomena can be dangerous.
Around a dozen people are said to have been killed by the Old Sow. Thankfully, a visit to a huge whirlpool is less risky for larger vessels and modern boats so tourists can go and see these natural wonders without putting themselves in harm’s way.
These swirling eddies can also be beneficial for marine life because they oxygenate the water and bring nutrients to the surface.
The Old Sow is popular with wildlife watchers who visit in the hope of spotting minke whales, puffins, porpoises and seals as well as various other seabirds.
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People even go scuba diving at Saltstraumen to see cod, haddock, pollock and wolffish – but they have to time their visit incredibly carefully. "You have a small window where you can dive, just as the current shifts,” divemaster Borghild Viem from Nord&Ne tells Visit Norway. “You'll have about an hour in total, before the washing machine, as I call it, starts again.”
top image: Current tide at Saltstraumen maelstrom in Norway. Credit: RelaxFoto.de/ Getty Images
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