What can it be, this homing instinct, that brings the birds back to us every year? That brings the wrens and the swallows to the very same nests around the house and barn? That leads the carrier pigeon home across a hundred, five hundred miles?
The trainer of pigeons has something significant to tell about this. He cannot release his birds for the first time in Moscow and expect them to fly home to Paris. He must first take them not a mile from home, and when they have learned all landmarks thoroughly, he may take them thirty or forty miles away. Each pigeon must be educated in its route. Birds, then, in their mirgrations would seem to have a memory for landmarks, and flying very high as they do, they see so much country in one little eyeful that the memory need not be burdened with a crushing weight of detail.
But the slippery question of the ways of birds upon their majestic travels will not rest as this. If it be true that the young of the season, who have never made the flight before, often travel in little jaunty bands of adolescents, as they appear to, without the oldsters accompanying them, then memory of landmarks cannot be all the story. Something else draws on their restless wings across the sea and the unbroken forest, some feeling in their light, air-filled bones, that sweeps them north in a grand phalanx in spring, and surges south with them in autumn.
More information on our Almanac For Moderns project and the work of Donald Culross Peattie can be found here.