DRUCKER: COHO SALMON OF KARLUK RIVER SYSTEM 



67 MEAN 



JUNE 22) 



22 ) 



TIME PERIOD 



Figure 9. — Migration of echo salmon smolts by time period from Karluk Lake for the 



years 1961-67, 



of the age 2 smolts migrated in daylight (Semko, 

 1954.) At Bear Creek, Alaska, 49.8^r of the 

 smolts migrated between 0400 and 2000 hr in 

 1962 (see footnote 1, Table 1), and W/c mi- 

 grated between 0900 and 1700 hr in 1964 (see 

 footnote 2, Table 3). 



AGE 



In 1956, 1965, and 1968, scale samples taken 

 from seaward-migrating coho salmon smolts at 

 the Karluk Lake weir revealed that the dom- 

 inant ages were 2 and 3 and that the age com- 

 position was similar between years (Table 6). 



The freshwater age composition determined 

 from the scales of adults collected in 1966 was 

 strikingly similar to the age composition of sea- 



Table 6. — Freshwater age composition of Karluk Lake 

 coho salmon as determined from smolt and adult scale 

 samples. 



ward-migrating smolts in 1965 — smolts that pro- 

 duced the adults in 1966 (Table 6). The only 

 group missing from the adult scale sample but 

 present in small numbers in the smolt scale sam- 

 ples was age 1 (fish that went to sea in their 

 second year of life). Fish from this age class 

 could have been missing in the returning adults 



89 



