Page:Popular Science Monthly Volume 7.djvu/197

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THE MIGRATION OF INLAND BIRDS.
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a family not only, but to all of the various species separately, of which a score or more pass through the State as a general thing. During certain seasons we have noticed a marked preponderance of some one or two warblers, which for seasons following were much less common than many others. Thus, in 1860, 1864, 1867, and 1872, the common redstarts (Setophaga ruticilla) were very abundant, not only about their natural haunts, but within the city limits, and scores of them could be seen climbing over and flitting through the branches of the shade-trees of the less-frequented streets. Since 1872 these birds have not been so numerous as usual, and far less so than many other warblers, such as the yellow-rumped (Dendroica coronata), the black-throated blue (D. cærulescens), or even the chestnut-sided (D. Pennsylvanica).

Unlike the thrushes, the warblers seem to be wholly controlled by meteorological influences and sudden changes of the weather, which, unlike some birds, they seem unable to foretell, greatly influence their movements, and certainly delay their northward progress; and yet, while we have frequently known them to be caught in a "northeaster," they are not otherwise affected by it, so far as we could determine, other than by the delay, before mentioned. Even a sudden change from warm, summer-like weather to decided cold did not destroy any of them, apparently, or check their lively movements among the trees.

Let us glance at the well-known and noticed swallows. For five months of every year we have with us, in greater or less abundance, six species of swallows and one "swift," the common chimney-swallow. Of these, one, the rough-winged (Stelgidopteryx serripennis) is comparatively rare, and known only to ornithologists; the white-bellied (Hirundo bicolor) are not particularly abundant, except during certain seasons; the cliff-swallow (Petrochelidon lunifrons) is erratic, now here, about the barns and stables of a circumscribed neighborhood, for several years, and then wholly failing to appear in their former haunts, when spring comes slowly up this way, to greet May's sleeping blossoms. Not so, however, with the barn-swallow (Hirundo horreorum); with a variation in date of arrival of about ten days, we have come to us, in May, our full complement of these beautiful birds. They have decreased in numbers during the past thirty years, so observant old farmers have told us, but probably not so much as they think. It is more probably the increase in the numbers of other species that makes the numbers of the barn-swallow seem fewer. The bank-swallow (Cotyle riparia), earliest of all, is here literally by millions, and the purple martin (Progne subis), in moderate numbers, seldom fails to occupy the boxes placed for its accommodation; while, lastly, the chimney-swallow (Chætura pelagica), which really belongs to another family, nearer the humming-birds and goat-suckers, we believe, has never failed to appear in about the same numbers, year after