CONTENTS 



Introduction 



Part I. Fur seal investigations, Pribilof Islands, Alaska, 1968 



Age classification and number of seals killed by sex 



Males 



Females 



Survey data 



Dead seal pups counted 



Causes of seal pup mortality 



Malnutrition , . . . . 



Hookworm disease 



Trauma 



Multiple hemorrhage-perinatal complex 



Infection (microbial) 



Miscellaneous 



Seasonal and annual trends in seal pup mortality 



Dead seals counted that were older than pups 



Living adult male seals counted 



Reproductive condition of female seals 



Living pups weighed 



Marking 



Application of marks 



Pups 



Yearling male seals 



Male seals age 2 years 



Recoveries of marked seals 



Marked seals 



Tag loss 



Time of tagging 



Tags vs. other marks 



Population estimates 



Number of seal pups born 



Number of yearling male seals 



Number of male seals age 2 years 



Forecast of the kill of male seals 



Quantitative comparisons for 3- and 4-year-old male seals 



Forecast of the kill of 4-year-old male seals 



Regression of the kill of 4-year-old male seals on the kill of 3-year-old 

 male seals and the mean round of the kill of 3-year-old male seals .... 



Regression of the kill at ages 3 and 4 on mean air temperature 



Regression of the kill at ages 3 and 4 on the mean weight of living seal 



pups and the count of dead seal pups 



Estimate of the kill based on an estimate of the yearling male seal popu- 

 lation 



Combined estimates of the kill of 4-year-old male seals on St. Paul Island. 



Forecast of the kill of 3-year-old male seals 



Regression of kill at ages 3 and 4 on air temperature, mean weights of 



living seal pups, and counts of dead seal pups 



Forecast of the kill at age 3 based on an estimate of the yearling male seal 



population 



Combined estimates of the kill of 3-year-old male seals on St. Paul Island. 



Estimates of the total kill of male seals in 1969 



Special studies 



Activity of young male seals on land 



Tagging 



Telemetry 



Adult male seals on the hauling grounds 



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