CONTENTS

Page
Introduction[1]
Mystery of migration[3]
Historical accounts[3]
Advantages of migration[4]
Theories of causes of migration[5]
When birds migrate[7]
Movements of species and groups[8]
Nocturnal and diurnal migration[11]
How birds migrate[13]
Speed of flight and speed of migration[13]
Altitudes at which birds travel[22]
Orientation[23]
Segregation during migration[25]
Where birds migrate[27]
Distances of migration vary[27]
Short and undetermined migration[27]
Variable migrations within species[28]
Fall flights not far south of breeding ranges[29]
Long-distance migrations[30]
Routes of migration[33]
Wide and narrow migration lanes[34]
Atlantic oceanic route[39]
Atlantic coast route and tributaries[42]
Mackenzie Valley-Great Lakes-Mississippi Valley
route and tributaries		[45]
Pacific coast route[47]
Pacific oceanic route[49]
Arctic routes[52]
Evolution of migration routes[52]
Vertical migration[55]
Vagrant migration[55]
Perils of migration[56]
Storms[56]
Aerial obstructions[57]
Exhaustion[59]
Influence of the weather on migration[59]
Problems of migration[61]
Banding studies[61]
Movements of residents[62]
Migration of the white-throated sparrow[63]
Migration of the yellow-billed loon[63]
Conclusions[65]
Bibliography[66]
Index[69]