Baby, it's cold outside

When the temperature drops, how do Britain's birds, beasts and plants keep the chill at bay? John Lewis-Stempel reveals Nature's own thermals

- John Lewis-Stempel

WE have all seen it. You are driving over the moor in dead winter, the snow descending unceasing; but, by the wayside, there is an Exmoor pony, or a Welsh, grazing unconcernedly. Or, you open the bedroom curtains on a January morning, the garden mummified in mortal white frost, and a tiny, fragile wren is, somehow, hopping perkily about the acacias.

How do they survive the depths of winter, the animals and the birds? Winter in Britain is variable, yes, often mild and wet, but then it soars in all its cold majesty. In English, the seasons are not capitalised, but Winter must be. Winter, with the majuscule initial, Winter with its ice and its snow. Winter when the pond freezes over with a pale ice lid, the snow builds unremittingly to the hedge top and the earth of the wheat field is cast in iron, unyielding to the beak of the rook. We humans flip up the car heating, turn around the dial of the house thermostat, shove an extra dog on the bed. Yet, the natural things outside, really, how do they survive?

They have their stratagems, the wild things. Most obviously, flee! Hence the pre-hibernal migration of our avian summer visitors, the swallow, the warbler, the cuckoo and all, southing to warmer climes, the avian Club Med, even beyond. Our resident birds are also cognisant of the evasion manoeuvre, the flight before the white storm, with the curlew gliding down on its long wings from high moor to low coast, a continental difference in climate—the seashore rarely freezes.

Smaller birds, the passerines, the finches and the larks, may join travelling bands to stay in front of the talons of the wind, constantly alighting, pecking for food. Winter, after all, has two killing claws: the cold and the lack of food, both of them requiring dressing in initial capitals like Winter itself. These are Hypothermia and its handmaiden Famine.