“There is a Power whose care
Teaches thy way along that pathless coast,
The desert and illimitable air,
Lone wandering, but not lost.”
This may seem like begging the question; yet, to my mind, it is impossible to develop a philosophy of the universe without assuming an original creative Intelligence. True, the laws of evolution will account for many of the details, and birds, like men, are empowered in a large measure to work out their own destiny; but somewhere there must be a Power that has infused into Nature all these wonderful potentialities of development. Involution must precede evolution.
But this is speculation. Account for them as we may, the facts are evident. Within the circle of my own observation there is abundant proof of this varied but wise adaptation in Nature. There, for example, is the tiny golden-crested kinglet, which remains here all winter, no matter how severe the weather, and seems to be the embodiment of good cheer; whereas the brown thrasher, a bird many times as large, would be likely to perish in the first snow-squall. Then, when spring arrives, Master Kinglet hies to the north for the breeding-season, while Monsieur Thrasher comes up from the south and becomes my all-summer intimate.
Another matter of intense interest concerning bird migration is that the migrants which winter farthest north are, as a rule, the first to arrive in the spring at their summer homes or vernal feeding-grounds. For instance, in the latter part of March or the beginning of April, while the thrashers, cat-birds, and others which winter in our Southern States, are arriving in New England, New York, Pennsylvania, and Ohio, the warbler army, which spends the winter in the West Indies, Yucatan, and Central America, is just crossing over from those countries to the southern borders of the United States.
When autumn comes, experience has taught the migrants that their only safety lies in making their way to the south before cold weather sets in; for many of them certainly do start on this voyage long before winter drives them from their northern haunts. In my opinion, they are gifted with sufficient reason—call it instinct, if you like—to do this, and I do not think they are moved by an uncontrollable impulse which acts upon them as if they were mere automata.
Portions of the migrating army often overlap. For example, the juncos and tree-sparrows are winter residents in my neighborhood, but very frequently they remain here a month or more after the earliest arrivals from the south. Presently, however, they grow nervous, flit about uneasily, trill little snatches of song, inure themselves to flight by longer or shorter excursions about the country, and then join the northward procession en route for their breeding-haunts in British America. With regret I bid them adieu, but find compensation in the knowledge that their places will be supplied by a brilliant company of summer residents.
One of the strangest features of migration is the fact that a bird will sometimes make the voyage from north to south, and vice versa—or a part of the voyage—alone, at least as far as companionship with individuals of its own kind is concerned. Whether this is done advertently or inadvertently I am unable to say, but the fact cannot be disputed. In the spring of 1892, as noted in another chapter, a hooded warbler was flitting about a gravel bank in a wooded hollow, and although I scoured the country for miles around day after day, I never met another bird of this species. The little Apollo in feathers was so gentle and familiar that surely his mates would not have escaped my notice had there been any in the neighborhood. Why he preferred to travel alone, or in company with other species rather than his own kin, might be an interesting problem in avian psychology. A little farther down the glen a single mourning warbler was also seen at almost the same date. His companions had probably wished him bon voyage, and left him to strike out in an independent course through the trackless ocean of air.