Using this book Bird migration is a complex subject, and knowledge of patterns of movement for some species and in many areas of the world is, at best, sketchy. The information given in this book is accurate, as far as is currently known, but the subject remains one about which there is much yet to be discovered. Within each chapter, species are arranged according to the systematic order, which is approximately the order in why they evolved. This scientifically accepted system has the advantage over other methods of organization that birds that are related are grouped together. Species have been chosen for inclusion on one of two major criteria: their migrations are typical of one or more patterns of movement and/or there are interesting stories associated with their migrations. Common names for birds tend to vary and are often a matter of choice or editor's preference; those used in the book reflect general usage as far as possible. [Information is also provided on using: "The maps," "The Calendars," "The Fact Files," and "Symbols and Abbreviations."] -- Introduction: Birds on the move Migration is probably the most awe-inspiring natural phenomenon. What it lacks compared with the enormous power of the weather, an earthquake, or a volcano, it makes up for in romance -- a small bird pits its wits against the elements and accomplishes, as routine, a journey that is truly superhuman. Outlandish theories have been proposed to explain the seasonal ebb and flow of bird populations, including that the birds went to the moon, were transformed into other species, or spent the winter in the mud of lakes or ponds. The knowledge of what really happens is, in many ways, no less fantastic. Over the centuries, people have struggled to understand birds' migrations and how they manage them year after year. How can they fly such tremendous distances without becoming lost or so exhausted that they die? How have today's complex migration patterns evolved from what were once, presumably, simple movements? And what particular problems are migratory birds facing now and are they coping? Although many parts of the mystery have been unraveled, there is still much that remains to be discovered about this fascinating phenomenon. Excerpted from The Atlas of Bird Migration: Tracing the Great Journeys of the World's Birds All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.
