TABLE OF CONTENTS 



Page 

 PREFACE 1 



INTRODUCTION 2 



THE HISTORY AND SCOPE OF MIGRATION 4 



TECHNIQUES FOR STUDYING MIGRATION 7 



Direct Observation 7 



Aural 8 



Preserved Specimens 8 



Marking 8 



Bands, Collars, Streamers 8 



Radio Tracking 10 



Radar Observation 10 



Laboratory 11 



Orientation and Navigation 11 



Physiology of Migration 11 



ADVANTAGES OF MIGRATION 13 



STIMULUS FOR MIGRATION 15 



WHEN BIRDS MIGRATE 17 



Time of Year 17 



Time of Day 20 



SPEED OF FLIGHT AND MIGRATION 25 



ALTITUDE OF FLIGHT AND MIGRATION 32 



SEGREGATION DURING MIGRATION 35 



By Individuals or Groups of Species 35 



By Age 36 



By Sex 38 



By Kinds of Flocks 40 



WHERE BIRDS MIGRATE 41 



Migration by Populations Within Species 41 



Fall Flights Not Far South of Breeding Range 42 



Long Distance Migration 44 



ORIENTATION AND NAVIGATION 47 



INFLUENCE OF WEATHER 51 



INFLUENCE OF TOPOGRAPHY 56 



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