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The several important bird-protective measures adopted by State and Federal Governments, particularly those having as their objectives the conservation of the migratory song, insectivorous, and game species, can be effective only if they have intelligent public support. To increase such support, information must be more generally available on that little understood but universally fascinating subject of bird migration. A brief presentation of facts on the migratory habits of the birds scientifically gathered by the Fish and Wildlife Service over many years, will be helpful to bird-study classes, to conservation organizations, and to farmers and others individually interested in the welfare of the birds.

In addition to his original investigations in the field and in the files of the Fish and Wildlife Service, the author has made free use of the writings of many other students of the subject. To all of these grateful acknowledgment is made.

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Of observers whose writings are extant, Aristotle, naturalist and philosopher of ancient Greece, was one of the first to discuss the subject of bird migration. He noted that cranes traveled from the steppes of Scythia to the marshes at the headwaters of the Nile, and that pelicans, geese, swans, rails, doves, and many other birds likewise passed to warmer regions to spend the winter. In the earliest years of the Christian era, the elder Pliny, Roman naturalist, in his Historia Naturalis, repeated much of what Aristotle had said on migration and added comments of his own concerning the movements of the European blackbird, the starling, and the thrushes.