More commonly seen in the Antarctic, the “ice pancakes” have formed in a quiet spot of the River Dee, the first time they have been seen in the area by those who work on the river.
The discs are made up of foam or slush on top which freezes, and is bashed into a circular shape by colliding with others as they float on the water.
Jamie Urquhart, a biologist at the River Dee Trust, photographed the ice pancakes when he spotted them at the Lummels Pool at Birse, near Aboyne, Aberdeenshire last week.
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He said today: “I’ve actually seen them before at the River Brora in Sutherland a couple of winters ago, but they were much smaller - more the size of a saucer.
“It’s the first time we’ve seen them at the Dee. They are quite a rare occurrence, the conditions have to be right for them to occur.
“I’ve spoken to a number of people across the catchment, the people on the river, such as the ghillies and anglers, who have never seen them here before.”
The ice pancakes have formed in a pool downstream from a fast-flowing part of the river, where the foam and froth gathers and circles together.
It is believed the foam froze overnight, and as it bashed into other frozen pieces, formed the dinner plate-sized ice pancakes.
It is thought the rim is created due to rising temperatures during the day and the cooler nights.
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