12 3 4 5 

 1949 



2 3 4 5 

 1950 



2 3 4 5 



1951 



1 2 3 



1952 



4 5 I 



2 3 4 5 

 1953 



AGES a YEARS 



Figure 10. - Age composition of downstream -migrant bluebacks caught 

 at Bonneville Dam, 1949-53. 



15 



