Country & Garden: Nature Notes

PTARMIGAN ARE among the highest-living birds in Britain. Cousins of the red grouse, they inhabit the rocky upper ranges of the Scottish Highlands, and rarely come down below 2,000ft.

I once asked a gamekeeper what they live on, and he replied, "Stones, mostly." In fact they eat heather shoots, bilberries, crowberries, seeds and insects. In winter they often have to burrow into snow to find food.

At this time of year they are still in their autumn plumage of grey and white, but in winter they turn pure white all over as a form of camouflage in the snow. In places where they rarely see humans the birds are often extremely tame; a whole covey will toddle along through the rocks a few yards in front of any hiker, not bothering to fly off.

In windy weather they become very wild, and take off in a whirl of white wings the moment an intruder appears. Their main enemies are golden eagles and peregrine falcons, against which their best defence is immobility; if they huddle down and keep still among stones, or in the snow, the predators often fail to spot them.

A ptarmigan's territorial call is strangely mechanical: a steady whirring maintained for several seconds, which sounds like a barn door opening on rusty hinges.

Duff Hart-Davis