| Page | |
| The mystery of migration | 4 |
| Advantages of migration | 6 |
| The origin of migration | 7 |
| Northern ancestral home theory | 8 |
| Southern ancestral home theory | 8 |
| Theory of photoperiodism | 9 |
| Theory of continental drift | 11 |
| When birds migrate | 11 |
| Movements of species and groups | 12 |
| Nocturnal and diurnal migration | 15 |
| How birds migrate | 18 |
| Speed of flight and speed of migration | 18 |
| Altitude at which birds travel | 26 |
| Orientation | 28 |
| Segregation during migration | 31 |
| Where birds migrate | 34 |
| Short and undetermined migrations | 34 |
| Variable migrations within species | 35 |
| Fall flights not far south of breeding ranges | 37 |
| Long-distance migrations | 38 |
| Routes of migration | 41 |
| Wide and narrow migration lanes | 42 |
| The fly ways | 46 |
| Atlantic oceanic route | 48 |
| Atlantic coast route and tributaries | 53 |
| Mackenzie Valley—Great Lakes—Mississippi Valley Route and tributaries |
60 |
| Great Plains—Rocky Mountain routes | 62 |
| Pacific coast route | 63 |
| Pacific oceanic route | 66 |
| Arctic routes | 68 |
| Evolution of migration routes | 70 |
| Vertical migration | 72 |
| Vagrant migration | 73 |
| Perils of migration | 75 |
| Storms | 75 |
| Aerial obstructions | 76 |
| Exhaustion | 78 |
| Influence of the weather on migration | 80 |
| Problems of migration | 81 |
| Banding studies | 81 |
| Movements of residents | 82 |
| Migration of the white-throated sparrow | 84 |
| Migration of the yellow-billed loon | 84 |
| Conclusions | 85 |
| Appendix I—List of birds mentioned in the text | 87 |
| Appendix II—Bird banding | 92 |
| Bibliography | 94 |
| Index | 99 |