Photographer Martin Le-May recently captured an extraordinary image of a weasel clinging to the back of a green woodpecker during flight.

The incredible photo has gone viral, and while some people have questioned the picture's authenticity, experts say it’s the real deal.

Le-May told ITV News that he snapped the photo Monday afternoon while taking a walk through a London park with his wife.

"I heard a distressed squawking noise and feared the worst," he said. "I soon realized it was a woodpecker with some kind of small mammal on its back."

Le-May and his wife grabbed their binoculars and watched as the bird hopped and flapped its wings, trying to dislodge the weasel.

"Just after I switched from my binoculars to my camera the bird flew across us and slightly in our direction; suddenly it was obvious it had a small mammal on its back and this was a struggle for life."

The woodpecker landed in front of Le-May, and he thinks his presence startled the weasel, giving the bird time to escape.

Zoologist Lucy Cooke told BBC News that woodpeckers aren't typical prey for weasels, but she said the small mammals are fearless.

"A female weasel weighs less than a Mars Bar but is as ferocious as a lion, so this is why the woodpecker would have been able to take off with it on its back," she said.

Weasels are known for having a "small person complex" and are often more fierce than their size would suggest.

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