The three huge corpses were discovered at different points along the west coast of Colonsay, in the Hebrides, in August.
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The carcasses were covered in debris, making the species difficult to determine.
The decomposing bodies also smelled so bad that no one wanted to approach them.
However, three months later, the debris has blown away to reveal the animals' remains have distinctive white pelts.
Locals now believe the remains are those of polar bears.
The nearest habitat of the creatures is in the Arctic, 1400 miles from the island. But in recent years, the creatures have been recorded drifting from their natural habitat on ice floes as global warming takes its toll.
Colin Flower, a 70-year-old working at the farm where one of the bodies is now being kept, said he concluded the animals were polar bears after examining them over the weekend.s
Colin said: "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."
His conclusion was shared on Saturday via the Friends of Colonsay Facebook page.
The site admin wrote: "We must assume that a small family was marooned upon an ice floe which melted, causing them to drown."