大象传媒

Tweet of the Day is a series of fascinating stories about our British birds inspired by their calls and songs.

David Attenborough presents the ptarmigan. Few birds are tough enough to brave winter on the highest of Scottish mountains but Ptarmigan are well adapted to extreme conditions. They're the only British bird that turns white in winter and Ptarmigan have feathers that cover their toes, feet and nostrils to minimise heat loss.