Three giant corpses washed up at different points on the west coast of Colonsay, in the Inner Hebrides, in August.
Nobody was able to confidently identify the bodies at the time, as they were covered in debris and smelled so bad that nobody wanted to approach them.
After being left for three months the debris has blown away to reveal the animals have white pelts, and locals are convinced they must be polar bears.
And they believe that the arrival of the dead creatures on the beach - 1,400 miles or about 2,200km from the nearest habitat of the bears - could be a sympton of global warming.
Instances of polar bears drifting from their national habitat on ice floes have been recorded in the past few years as sea ice is breaking up earlier each spring and freezing later each autumn due to global temperatures rising.
Colonsay Islander Kevin Byrne, one of the first people to see the carcasses when they arrived in August, explained that islanders were initially unable to identify them.
He said: “The bodies came ashore two or three months ago, and we were puzzled immensely.
“They were big lumps that seemed to have hair and limbs, but they were very, very smelly. Some people thought they were deep sea creatures and others ‘imagined’ they had hooves.
“They were dragged up away from the beach, and we thought, when they rotted down we’d get a look at the skeleton. Then, recently, a man called Colin Flower suddenly realised what they were. They are polar bears.”
The 69-year-old added: “If the icecap is melting, the Arctic will become an open ocean so there will be a change in currents. If it melts, one might imagine that water from that open area will flow south, towards the equator, to feed convection and condensation/evaporation.
“That water would be replaced by a converse flow - like the Bosphorus. If the water flowing south were to be on the surface, it would be the exact opposite of the existing arrangement, and would explain the bears.”
Colin Flower, a 70-year-old working at the farm where one of the bears is now being kept, said that he came to conclude that the animals were polar bears after examining them over the weekend.
Colin said: “Initially, these were grey blobs, they didn’t look like anything. Even a vet who had a look couldn’t come to a conclusion.
“Now, this grey coating covering them has blown away, or at least that’s my theory, and a white pelt is now visible.
“They are three metres long and you can also make out a head and eye socket now.
“I can’t see what else it could be? There’s no other sea creature that has that fur.”
The discovery was shared with local people on Saturday via the Friends of Colonsay Facebook page.
The admin for the page shared an image of the polar bear, and wrote: “Many Friends will remember the four mystery remains that came ashore here. They seemed to be covered in hair, had hooves, smelt of blubber. They were examined by doctors and veterinarians, a rumour started that they were horses.”
The admin explained that a local farmer “hauled one carcass clear of the sea at Port Easdail and it has now begun to reveal its structure.
“Colin Flower has had a close look, it is a polar bear! We must assume that a small family was marooned upon an ice floe which melted, causing them to drown.”
In 2010, British magazine Country Life published a spoof article on April Fool’s Day, claiming that a live polar bear had somehow washed up on the Isle of Mull.