MOSHER: SCALE FEATURES OF SOCKEYE SALMON 



Table 8. — Percentage frequency distribution' of circuli (A) in the total freshwater zone and (B) in the first ocean 

 zone of age 3. sockeye salmon collected in various years from 1955 to 1964. 



(A) (B) 



zone. Adventitious checks in other zones are 

 not noted. 



AGE 0., ALL AREAS (Plate I) 



As noted previously, age 0. sockeye salmon 

 are not common anywhere since fish of this spe- 

 cies normally live for one or more years in a 

 lake before migrating to the sea. Consequently, 



it was not possible to assemble frequency dis- 

 tributions of the number of circuli in the first 

 ocean zone for age 0. fish. It appears, however, 

 that usually there are a few more circuli in the 

 first ocean zone of scales of age 0. than on scales 

 from fish of the same geographical area that 

 have lived one or more years in fresh water. 

 A few individuals of this age have been found 

 at some time in almost every locality. Gilbert 



151 



