THE WHITE SEA - Dan Burton was 26ft under the Russian White Sea when a beluga whale appeared and locked its jaw around him. Above, on the surface, lay a foot of ice. The water was minus 2C (28.4F).

“It grabbed hold of my arm and my leg with its mouth. It locked on tight,” said Mr Burton, 41. “I think the beluga was testing me. It wasn’t actually trying to bite me. I was a bit nervous, but at least it wasn’t a great white.”

Mr Burton, a self-styled extreme photographer from Devon, was taking pictures of Julia Petrik, 36, one of the world’s leading free-divers, with the whales. Every year she and other Russian free-divers gather along the northwest coast to go diving with the belugas, which inhabit the sub-Arctic waters of the White Sea and can grow to 16ft.

“The way Julia moves through the water is just incredible,” said Mr Burton. But while Ms Petrik was offered a free ride on one whale’s back, Mr Burton’s encounter did not go quite so smoothly.

He insisted, however, that despite the “snowing, blizzardy and grey conditions, the black water, the floating chunks of ice” and his brush with a beluga, the experience was all “fairly run of the mill”.

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