CONTENTS 



Page 



Introduction 1 



Population 3 



Males 3 



Age classification 3 



Bull counts 7 



females 8 



Methods used in current studies 8 



Age classification 9 



Reproduction 11 



Tag recoveries and tagging 12 



Tag recoveries 12 



Taggmg--pups 12 



Tagging--yearlings 14 



Survey--yearlings 18 



Appraisal of problems involved in tagging and tag recoveries 19 



Results of double tagging 20 



Homing tendency 21 



Mortality 23 



Total dead-pup counts 23 



Dead-pup counts on sample areas 23 



Population estimates 24 



Estimates from tagged males 24 



Estimates from tagged females 26 



Estimates from pup sampling 26 



Discussion of estimates 27 



Seal pup weights 29 



Measurements of 3-year-old males 31 



Related studies 31 



Live-pup counts 31 



Experimental skins 32 



Dentition studies 32 



Plastic impression technique for studying sealskins 33 



Eye lens weight as an indicator of age 33 



Age of the fur seal pup at completion of its first molt 33 



Other wildlife species 33 



Sea lions 33 



Whales 33 



Walrus 33 



Sea otter , 33 



Reindeer 33 



Summary 34 



Acknowledgments 35 



Literature cited 35 



Glossary 36 



Appendix A. Prediction of 1964 male returns and kill 37 



Appendix B. Appendix tables 40 



FIGURES 



No . 



1. Kill of 3- and 4-year-old male seals, by round, St. Paul Island, 1963 7 



2. Percent 3- and 4-year-old male seals in cumulative kill, by date, Pribilof Islands, 



Alaska, 1963 7 



3. Length classes of 701 selected yearlings, St. Paul Island, 1963 16 



4. Length classes of 98 known-age yearlings, St. Paul Island, 1963 16 



5. Comparison of length classes of selected and known-age yearlings, St. Paul Island, 



1963 16 



6. Pup shearing, St. Paul Island, 1963 27 



