The gyrfalcon (Falco rusticolus), the largest of the falcon species, is a bird of prey. It breeds on Arctic coasts and tundra, and the islands of northern North America and the Eurosiberian region. Its plumage varies with location, with birds being coloured from all-white to dark brown. These colour variations are called morphs. Like other falcons, it shows sexual dimorphism, with the female much larger than the male.
I was lucky enough to photograph her in Denmark. I have been told, later, by bird-watchers (some very sad as they missed her) that she is probably a visitor from Norway due to her colors (again I learnt that Icelandic ones are usually white).
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