The Lay of the Land

by Dallas Lore Sharp

Not far from my house is a nest of black-crowned night herons, or “quawks.” Preparatory to the mating of the pair there started from the crown of the male (and female, also, in this case,) two or three white, rounded plumes, which now hang eight inches in length, waving gracefully to his shoulders. They are the special glory of the wedding time; but soon after the nesting season is over they will drop out, not to come again until he goes a-wooing Mrs. Quawk once more. In the white American egret, and in the snowy egret, the plumes number about fifty, and occur upon the back close to the tail. They are straight in the American, recurved in the snowy, and make the famous “aigrette” plumes of the milliner. The birds are shot in their nuptial dress, and so great has been the heartless demand that both species, once very abundant, are now almost extinct.

Bobolink is another special case. He has two complete moults a year. Now, as I write, I hear him singing over the meadow,—a jet black, white, and cream-buff lover, most strikingly adorned. His wife, down in the grass, looks as little like him as a sparrow looks like a blackbird. After the breeding season he moults, changing color so completely that he and his wife and children all look alike, all like sparrows. They even lose their name now, flying south under the assumed name of “reedbirds.”

Bobolink passes the winter in Brazil, and at the coming of spring, just before the long northward journey begins, he moults again; but you would hardly know it to look at him, for, strangely enough, he is not black and white, but still colored like a sparrow as he was in the fall. Apparently he is. Look at him more closely, however, and you will find the brownish yellow color is all caused by a veil of fine fringes hanging from the edges of the feathers. Underneath are the black and white and cream-buff. He starts northward, and by the time he reaches Massachusetts the fringe veil is worn off and the black and white bobolink appears. Specimens taken after their arrival here still show traces of the yellow veil.

Many birds do not have this spring moult at all, and with most of those that do, the great wing feathers are not then renewed as are bobolink’s, but only at the annual moult after the nesting is done. In fact, the moulting of the remiges, or wing feathers, seems to be a family affair, the process differing with different families; for these are the bird’s most important feathers, and their loss is so serious a matter that Nature has come to make the change according to the habits and needs of the birds.

With all birds the order is for the body feathers to begin to go first, then the wings, and last the tail. But the shedding of the wing feathers is a very slow and carefully regulated process. In the wild geese and other water birds the wing feathers drop out with the feathers of the body, and all go so simultaneously that the birds cannot fly. On land you could catch them with your hands, but they keep near or on the water and thus escape, though times have been when it was necessary to protect them from their human enemies at this season by special laws.

The necessity for the moult entails many risks, for it exposes the bird to peculiar dangers; yet no single bird is abandoned during this period, none left without a way of escape. The geese, as we have seen, moult most rapidly and hence are most helpless, but there are few of their enemies that they cannot avoid by keeping to the water and grassy marshes; the hawks, that hunt by wing, moult so slowly that they do not feel a loss of power; while such birds as the quail and grouse, that always depend in part for protection upon the blending of their colors with the colors of their environment, seem especially so protected during the moulting season. A grouse blotched with light patches, where the dark-tipped feathers have fallen away, may so melt into the mottled color scheme of its background as to escape the sharpest eye.

Such a rapid, wholesale moult as in the case of the geese would be fatal to land birds. Instead, their primaries, or large wing feathers, drop out one or two at a time and symmetrically from the two wings. Oftentimes it is the two inner primaries that go first, then the others following one at a time, the outermost last. This order varies, as in the kingfisher. In the snow bunting all but two of the old primaries are gone before any new ones have grown as large as the secondaries. In the hawks, again, birds that must use their wings and must have them always at their best, the moulting of the wing feathers is very slow, lasting nearly the whole year. The homing pigeon, another great flier, but not of the same kind as the hawks, begins about May to moult his wing feathers, losing the tenth primary first, a month later the ninth, then the others at intervals of from eight to fifteen days.

It is quite enough to make one pause, to make one even wonder, when he finds that this seemingly insignificant matter is taken so seriously by nature, and that even here there is that perfect adaptation of means to end. The gosling, to cite another instance, goes six weeks in down, then gets its first feathers, which it sheds in the fall. The young quail, on the other hand, is born with quills so far advanced that it is able to fly almost as soon as it is hatched. These are mature feathers; but the bird is still young and growing, and soon outgrows these first flight feathers, so that they are quickly lost and new ones come. This goes on till fall, several moults occurring the first summer to meet the increasing weight of the growing body.

Where there are peculiar uses made of the tail, as with the chimney swifts and woodpeckers, there is a peculiar order of moulting. In most birds the tail is a kind of balance or steering-gear, and not of equal importance with the wings. Nature, consequently, seems to have attached less importance to the feathers of the tail. They are not so firmly set, and they are hardly of the same quality or kind; for if a wing feather is once broken or lost, after the moult, it must go unmended until the annual moulting time comes round again; whereas, if a tail feather is lost through accident, it is made good, no matter when. How do you explain that? I know that old theory of the birds roosting with their tails out, and so, through generations of lost tails, those feathers now grow, expecting to be plucked by some enemy, and so have only a temporary hold. Perhaps.