from the area of heaviest fishing amounted to 

 378 per 1,000 fish tagged. The comparisons 

 follow: 



one locality to another varies with the distance 

 separating the stocks. Emigration of herring 

 stocks of the Lower East Coast of British Columbia 

 is lower than for other areas, but immigration 



Recoveries per 1,000 fish tagged 



Species and locality 



Year after tagging 



Pacific sardine- 

 Tagged off Baja California 

 Tagged off S . California 

 Tagged off C . California 



British Columbia herring 

 (1936-37 to 1951-52) 



2/ 

 Pacific halibut— 



(tagged in 1951) 



Total 



1/ From data given in Clark & Janssen, Calif. Div. Fish & Game, Fish Bull. No. 61 . 



2/ From data given in Reports of the International Pacific Halibut Commission, Nos. 20, 21, and 22. 



Taggings were carried out on all main her- 

 ring stocks in British Columbia waters in order 

 to determine the degree of discreteness of her- 

 ring populations . A summary of the percent 

 emigrating from and immigrating into the prin- 

 cipal areas ("populations ') is given in the follow- 

 ing tabulation: 



into this area is higher. 



Herring "populations" along the west coast 

 of Vancouver Island. --Tester (1949) summarized 

 extensive data gathered on herring "populations " 

 along the west coast of Vancouver Island: over 

 22,000 vertebral counts made on 12 consecutive 

 year classes from five contiguous areas. He 

 analyzed the data for variation between samples, 



There is a considerable mixture of herring 

 stocks along the British Columbia coasts . About 

 a fourth of the fish of each "population" emigrate 

 to other areas . The amount of emigration from 



between age groups, between year-classes and 

 between areas. He then proceeded to examine 

 the reliability of results in the light of tagging 

 experiments . 



55 



