The Cuckoo (Cuculus) is a scansorial or climbing bird, the type of the family Cuculidae, now almost extinct in Britain. The note from which it derives its name is a love-call used only in the mating season. The greater number of species belonging to the genus are confined to hot countries, more especially India and Africa, though some are summer visitants of colder climates. In America no true cuckoos are found, the genus Coccyzus, to which the so-called American Cuckoo belongs, differing very essentially from them in its habits. The species best known in Europe, the Cuculus canorus, is a bird about the size of a small pigeon, though the length of the tail gives it at a little distance a strong resemblance to a hawk.
The adult bird is ashy-grey in colour, with a white breast barred across with narrow lines of grayish black; tail spotted and barred with white; bill black, touched at the gape with yellow; eyes and feet yellow. It appears in England about the middle of April, and in May begins to deposit its eggs in the nests of other species, giving the preference to those of the hedge-sparrow, meadow-pipit, or pied wagtail. The young Cuckoo ejects from the nest its young companions, and monopolizes the attentions of its foster-parents, which feed it for about five weeks after it is fledged. The young birds do not leave the country until the end of August or even September; but the adult birds commence their flight southward in July or at latest early in August. Their food consists largely of caterpillars (especially hairy ones), Cuckoos are one of only three species of birds that eat Cinnabar Moth caterpillars, with cockchafers, moths, dragon-flies, and other insects.
The female Cuckoo lays six or eight eggs, and each is placed in a different nest, by means of the bird's bill, as has been ascertained, being first deposited on the ground. Different strains of Cuckoo utilise different species of bird, each strain concentrating only on one species, and laying an egg which is identical in appearance to the eggs of the host species. Thus, one British strain of Cuckoo targets the nest of Reed Warblers only, and lays an egg identical in appearnce to that laid by the Reed Warbler, and it is possibly this factor which enables the Cuckoo chick to remain being cared for by its adoptive parents, even though the chick may grow many times larger than its parents. Research Cuckoo
Abbreviations
Nature
Research Cuckoo