We have two species of cuckoo in the United States, but each of them builds a nest of its own, and rears its own young, although our yellow-billed cuckoo is a very bad nest-builder, and is said often to desert its young, leaving them to starve unless other birds take pity upon them and bring them food. Most of our smaller birds are very sympathetic during the breeding season, and are ready to give food and care to any young bird which needs it, even if it is not one of their own species.
Although our American cuckoos have not, as a general thing, the bad habits of those of Europe, we have another very common bird which is hatched and brought up by strangers. Every boy who lives in the country knows the cow-bird, cow-blackbird, or cow-bunting, for it is called by all these names. It is a small bird, a little larger than the bobolink and of much the same shape. The male has a dark-brown head and a bright greenish-black back and wings, but the female is so much lighter in color that you would hardly believe that they belong to the same species. These birds are very abundant in the spring and summer, and may be seen in flocks flying and feeding in company with the red-winged blackbirds. They are often found among the cattle and sheep in the pastures and barn-yards, and they derive all of their common names from this habit. Although nearly related to the orioles, which make such wonderful nests, the cow-birds make none at all, but lay their eggs in the nests of other birds, such as the blue-bird, chipping-bird, song-sparrow, yellow-bird, and some thrushes and fly-catchers. Like the cuckoo, this bird usually chooses the nest of a bird much smaller than itself, but as its egg is not small, the deception is at once discovered, and the birds whose nest has been selected for this purpose are very much disturbed. It is necessary for the female cow-bird to find a nest in which the owners have just begun laying, for if the owners have no eggs of their own they will desert the nest, and if their own eggs are somewhat advanced before the cow-bird's egg is laid, their own young will hatch first, and the parents will then leave the nest to hunt for food, thus allowing the cow-bird's egg to become cold and die.