British Birds in Their Haunts

by C. A. Johns

The Cuckoo hunts for its food both in trees and on the ground. On its first arrival it lives principally on beetles, but when caterpillars become abundant it prefers them, especially the hairy sorts. In the months of May and June, the female Cuckoo lays her eggs (the number of which is variously estimated from five to twelve), choosing a separate locality for each, and that invariably the nest of some other bird. The nests in which the egg of a Cuckoo has been found in this country are those of the Hedge Sparrow, Robin, Redstart, Whitethroat, Willow Warbler, Sedge Warbler, Wagtail, Pipit, Skylark, Yellow Bunting, Chaffinch, Greenfinch, Linnet, Blackbird and Wren; the Pipit being the most frequent. It has now been ascertained that the nests of birds in which the Cuckoo lays its eggs in different countries number 145 species.[24] In some of these instances, the position and structure of the nests were such that a bird of so large a size could not possibly have laid an egg in the usual way. Hence, and from other evidence, it is pretty clear that the egg is in all cases laid at a distance from the nest and carried by the bird in her bill to its destination. The bird can have no difficulty in accomplishing this seemingly hard task; for the gape of the Cuckoo is wide, and the egg disproportionately small, no larger in fact than the egg of the Skylark, a bird only a fourth of its size. The period during which a nest is fit for the reception of a Cuckoo's egg is short; if a time were chosen between the completion of the nest and the laying of the first egg by the rightful owner, the Cuckoo could have no security that her egg would receive incubation in good time, and again if the hen were sitting there would be no possibility of introducing her egg surreptitiously. She accordingly searches for a nest in which one egg or more is laid, and in the absence of the owner lays down her burden and departs. There are certain grave suspicions that the intruder sometimes makes room for her own egg by destroying those already laid; but this, if it be true, is exceptional. If it were very much larger than the rest, it might excite suspicion, and be either turned out, or be the cause of the nest being deserted; it would require, moreover, a longer incubation than the rest, and would either fail to be hatched, or produce a young Cuckoo at a time when his foster-brothers had grown strong enough to thwart his evil designs. As it is, after fourteen days' incubation, the eggs are hatched simultaneously, or nearly so, the Cuckoo being generally the first. No sooner does the young bird see the day, than he proceeds to secure for himself the whole space of the nest and the sole attention of his foster-parents, by insinuating himself under the other young birds and any eggs which may remain unhatched, and hurling them over the edge of the nest, where they are left to perish. 'The singularity of its shape', says Dr. Jenner, 'is well adapted for these purposes; for, different from other newly-hatched birds, its back from the shoulders downwards is very broad, with a considerable depression in the middle. To the question which naturally suggests itself, 'Why does the young Cuckoo thus monopolize the nest and the attentions of its foster parents?' the solution is plain. The newly-hatched bird must of necessity be less in size than the egg from which it proceeded, but a full-grown Cuckoo exceeds the dimensions of a whole brood of Pipits; its growth therefore must be rapid and cannot be maintained without a large supply of food. But the old birds could not possibly with their utmost exertions feed a brood of their own kind and satisfy the demands made by the appetite of the voracious stranger as well. The latter consequently saves them from this impossible task, and, by appropriating to his single use the nourishment intended for a brood of four or five, not only makes provision for his own well-being, but helps them out of a difficulty. So assiduously is he taken care of that he soon becomes a portly bird and fills his nest; in about three weeks he is able to fly, but for a period of four or five weeks more his foster-parents continue to feed him. It is probable that the young Cuckoo actually exercises some fascination over other birds. There is a case on record in which a pair of Meadow Pipits were seen to throw out their own young ones to make room for the intruder. In another instance, a young Cuckoo which had been taken from the nest and was being reared by hand escaped from confinement. Having one of its wings cut, it could not fly, but was found again, at the expiration of a month, within a few fields of the house where it was reared, and several little wild birds were in the act of feeding it. The Bishop of Norwich[25] mentions two instances in which a young Cuckoo in captivity was fed by a young Thrush which had only just learnt to feed itself.

In the days when omens were observed, it was considered a matter of high import to hear the song of the Nightingale before that of the Cuckoo. Thus Chaucer says:

it was a commone tale

That it were gode to here the Nightingale,

Moche rathir[4] than the lewde[5] Cuckowe singe.

So, when on a certain occasion he heard the Cuckoo first, and was troubled in consequence, he represents the Nightingale as thus addressing him: