They are known to be extremely social creatures that thrive in the freezing waters of the Artic.
So the discovery of a lone beluga whale off the coast of Seattle — almost 1,500 miles from its nearest population in Alaska — has left scientists baffled.
The wayward creature's 'very rare' appearance is the first documented sighting of a beluga whale in the inlet of Puget Sound in more than 80 years.
The closest beluga whale population is in Cook Inlet, Alaska, about 1,450 miles away.
Mystery: The discovery of a lone beluga whale off the coast of Seattle — almost 1,500 miles from its nearest population in Alaska — has left scientists baffled (stock image)
Belugas, also known as white whales, are known for having rounded foreheads and no dorsal fin.
The marine mammals feed feed on fish, crustaceans, and worms.
Ranging from 13ft to 20ft in length, the whales are common in the Arctic Ocean's coastal waters.
But they migrate southwards in large herds when the sea freezes over.
The whales, whose scientific name is Delphinapterus leucas, have an average life span in the wild is 35 to 50 yaers, and weigh around a tonne.
Experts are stumped as to how and why it ended up near Seattle but the fact it has been swimming close to three different shipyards has thrown up one theory.
'I don't understand the attraction of a shipyard to a beluga,' said Howard Garrett, co-founder of Orca Network, a non-profit organisation that raises awareness about whales in Puget Sound.
He told Live Science: 'I don't know if that's a clue, if that means it had been held captive at a shipyard somewhere at a busy port, but we have no documents, no idea of where that would be, certainly in North America.'
Two years ago another beluga whale hit the headlines when it appeared off Norway's coast sporting a Russian harness and camera attachment, prompting speculation it may have been acting as a spy for Moscow.
It was spotted by fishermen in April 2019 and again puzzled experts because belugas are so rarely seen that far south of the high Arctic.
An investigation was launched by Norway's domestic intelligence agency, which deemed that the whale was 'likely to have been part of a Russian research programme'.
There is no suggestion the Seattle beluga is anything to do with the Kremlin, however.
Secret agent? Two years ago another beluga whale hit the headlines when it appeared off Norway's coast sporting a Russian harness and camera attachment (pictured), prompting speculation it may have been acting as a spy for Moscow
Garrett's other thought is that it may just be a keen