Of 1,136 fur seals sighted off Washington, 334 were collected, 41 were wounded 

 and lost, and 42 were killed and lost. 



Solitary seals were more prevalent than paired or large groups of animals. 



Fifty-four percent of 299 females killed were from 1 to 7 years old, and 48 year- 

 ling seals from the 1968 year class were taken. 



Twenty-six marked seals were collected. 



Pregnancy rates have ranged from 38 to 90 percent for females age 5 and older 

 collected off Washington in February and March since 1958. 



Fifty-five percent of 140 fetuses collected in 1969 were males. 



Forty-eight percent of the nonpregnant seals 4 to 19 years of age had ovulated. 



Anchovy was the leading species in 190 stomachs that contained food. Rock- 

 fish, capelin, and salmonids followed in importance. Salmon were the most valuable 

 of the commercial fishes eaten by fur seals off Washington in 1969. 



INTRODUCTION 



In 1969 the Pribilof Islands fur seal pop- 

 ulation began its climb to a new level. Females 

 will not again be killed intentionally until about 

 450,000 pups are born annually. We are not 

 able to predict how many years will be required 

 for this level of pup production to be reached. 

 With average survival perhaps 5 years will 

 be needed to accumulate a total of more than 

 700,000 females 3 years old or older needed 

 to produce 450,000 young. Exceptional sur- 

 vival such as that experienced by the year 

 classes of 1952 and 1958 or poor survival like 

 that of the year class of 1956 will substantially 

 change the time required to bring the number 

 of females to the desired level. 



We believe the population is sufficiently re- 

 duced now so that density-dependent mortality 

 causes do not strongly influence it. The reason 

 for the extreme success or failure of some year 

 classes has not been determined. We suggest 

 that the variations are caused by changes in 

 the environment that we are not yet able to 

 relate to survival of fur seals. Forecasting the 

 strength of year classes depends on understand- 

 ing this relationship. Until we know and can 

 measure the factors that determine survival 

 to age 3 years, forecasts have limited usefulness 

 for the year intended. Their use in planning 

 sales of furs or for other economic uses 2 or 

 more years in the future is unwarranted. 



The distribution and numbers of fur seals 

 off Washington and southern British Columbia, 

 as well as their size, reproductive performance, 

 and food were studied. The studies, which are 

 coordinated with Canadian research, will be 

 carried on for several years. The results, in- 

 sofar as possible, will be correlated with the 

 population changes taking place on the Pribilof 

 Islands. 



Part I, on land investigations, was prepared 

 by the staff making studies on the Pribilof 

 Islands: Alton Y. Roppel, Project Leader 

 (Wildlife Research Biologist) ; Ancel M. John- 

 son, Biometrician (Wildlife Research Biolo- 

 gist) ; Raymond E. Anas, Fishery Research 

 Biologist; Mark C. Keyes, Research Veterinar- 

 ian; and Douglas G. Chapman (Director of 

 the Center for Quantitative Analysis, Univer- 

 sity of Washington, Contract No. 14-17-0001- 

 2146), consultant. 



Part II, on pelagic investigations, was com- 

 piled by staff biologists: Clifford H. Fiscus, 

 Project Leader (Wildlife Research Biologist); 

 and Hiroshi Kajimura, Fishery Research Bi- 

 ologist. Merrill A. Petterson and Stephen D. 

 Treacy, Biological Technicians, took part in 

 the 1969 operations. Temporary employees 

 Robert G. Forbes and Arthur A. Harvey as- 

 sisted with the ocean work. 



Ford Wilke, Laboratory Director 



