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Winter conditions: Stamps Blakeney filmed at night

January 17, 2015 at 12:43 GMT Last Updated

The "secret" and "busy" nightlife of the largest seal colony of England, based on the north coast of Norfolk, was filmed for the first time by the BBC winter conditions.

Using a thermal imaging camera found weapons of oxen "sneak" in areas under the cover of darkness, hoping to mate with harems of adult bulls unnoticed - which often in battle on the beach.

Winter weather presenter Iolo Williams said the images of Blakeney Point Reserve was "amazing".

"Sitting in the book of the moonlight, with more than 4,000 brands was the experience of a lifetime," he said.

Winter weather again BBC Two at 2100 GMT Monday, January 19th.