A Ptarmigan, Lagopus mutus, among granite rocks and a snow field in the Cairngorm mountains, Scotland, in March.

Ptarmigan are resident in the arctic-alpine zone of the Scottish Highlands, and remain on the mountain tops throughout the year.
In severe weather they seek shelter behind boulders or in the lee of a hill, and take cover from winter blizzards by digging into snow drifts, like snow-holers, where they remain insulated from the meteorological mayhem above.

As with mountain hares ptarmigan populations fluctuate, on cycles of around ten years. The Cairngorms' population is thought to vary by a factor of 10 or 20 between exceptionally good and poor years.

The birds' plumage changes to match the season. In winter they are snowy white, as here, and males like this one also have a red eye wattle.
By high summer they are mottled granite grey apart from, in flight, white wings.
Whatever the season their camouflage is remarkably effective.

Location: Highland Region, Scotland.