The Sleep of Birds
The gamekeeper perhaps sees more of sleeping birds than most people; and makes many interesting mental notes of the resting habits of creatures in his woods. He observes that perch-roosting birds always rest with their heads to the wind. If when a high wind is blowing a rook alights on the home-tree, he swings his head into the wind before settling. So when the wood-pigeons come home with the wind behind them they pass over their roosting trees, then beat up into the wind. This is done to defeat the force of the wind, which might prevent the bird alighting where desired, or might blow him from his perch. At rest, the bird doubles the knees, as it were, which causes the toes to contract, the weight of the body resting chiefly on the breast and on the outspread wings—not on the eggs, if in a nest. The birds' legs and feet have sinews which work an automatic locking action of the claws, so that, roosting with knees doubled up, the feet grip the branch unfailingly. On rough nights, the pheasants take the precaution of roosting in lower branches than usual. If a strong gale springs up after a bird has gone to roost on an exposed tree, it may be driven to seek a berth on the ground—and to the wind that does no good to the pheasant the passing fox owes his supper.
Some birds seem always half-awake. Wild-fowlers will strike a match at night to test the question of the presence or absence of wild duck in the distant creek; if present, an instant quacking will betray them. Pheasants seem ever vigilant, and on the darkest night it is difficult to stalk them unawares, however quietly you move. If you come within a hundred yards of guinea-fowl at night they will raise the alarm. They excel at talking in their sleep. Sparrow catchers know that directly their nets touch one part of an ivy-covered wall birds fly out from another. But some birds, such as the wrens when cuddling in a hole in the thatch, seem to sleep soundly. And while we have found that on striking a match beneath a tree where wild pigeons were roosting they have flown out at once with a clatter of wings, a pigeon-lover in London informs us that his city birds, roosting on his window-ledge, lose their wariness by night, and will hold their own in face of a candle, while a hand is outstretched to touch their necks.
As the day closes in, the partridges seek some sheltered, dry-lying hollow in the fields, and a covey of twenty birds will huddle on a spot a yard in diameter. The colder the weather the closer they roost. The birds on the edge of the ring have their breasts outwards. Sometimes, by the way, it is unfortunate for partridges and pheasants that the positions of their nests prevent them from flying to and fro. Having to force their way through tangled undergrowth, a trail is left for the fox to follow home. The barn-door fowl, in captivity, may walk from her nest; but when in possession of a stolen nest abroad, she resumes the flying habit. Fowls suffer frequently from deformed breast-bones, perhaps from roosting when their bones are young and soft. That they and their cocks are not heavy sleepers most people have cause to know.