Читать книгу Migration of Birds (1979) онлайн

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For more than three-quarters of a century the Fish and Wildlife Service and its predecessor, the Biological Survey, have been collecting data on the important details of bird migration. Scientists have gathered information concerning the distribution and seasonal movements of many species throughout the New World, from the Canadian archipelago south to the Argentine pampas. Supplementing these investigations is the work of hundreds of U.S. and Canadian university personnel and volunteer birdwatchers, who report on the migrations and status of birds as observed in their respective localities; while others place numbered bands on the legs of birds to determine their movements from one place to another. These data, stored in field notes, computer cards, scientific journals, and on magnetic tape constitute an enormous reservoir of information pertaining to the distribution and movements of North American birds. It is the purpose of this publication to summarize these data and present the more important facts about that little understood but universally fascinating subject of bird migration. The U.S. Fish and Wildlife Service is grateful to the many persons who have contributed their knowledge so that other people, be they bird study classes, conservation organizations, or just individuals interested in the welfare of the birds, may understand and enjoy this precious resource as well as preserve it for generations to come.