1950's. The reason for the decrease is not 

 clear because of uncertainties about the causes 

 of mortality at different sizes of the pup popu- 

 lation. To understand how mortality will change 

 as the size of the total pupulation changes, we 

 need to determiine the causes of death among 

 pups as the number of seals is allowed to 

 increase in successive steps. 



We have found that handling and marking 

 seal pups retards growth and probably reduces 

 survival. We, therefore, face the problem of 



how to get needed information without causing 

 unreasonable disturbance. 



This part of the report discusses research 

 data collected on the Pribilof Islands in 1966, 

 methods of forecasting the kill of male seals 

 in 1967, and results of special studies. Terms 

 having special meanings in fur seal research 

 are described in the glossary at the end of 

 part I. The locations of rookeries and hauling 

 grounds on St. Paul and St. George Islands 

 are shown in figures 1 and 2, 



'MORJOVI 



SEA LION 

 NECK 



LITTLE POLOVINA 



POLOVINA CLIFFS 

 POLOVINA 



ROOKERY AND 

 HAULING GROUND 



'REEF 



ARDIGUEN^ 



•^SEA LION ROCK 



Figure l.--Locatlons of rookeries and hauling grounds, St. Paul Island. 



