FISHERY BULLETIN: VOL. 82, NO. 1 

 Table 1.— Percentage downstream migration for fast-reared spring chinook salmon released into the Pelton ladder in 1977. 



TABLE 2. — Percentage downstream migration over semimonthly intervals for fast-reared spring 

 chinook salmon released into the Pelton ladder in 1978. 



Recovery of Released Fish 



In 1978, the greatest recovery of fish liberated into 

 Pelton ladder (92.5%) was from the large group of 

 1,000 fish released on 14 February (Table 2). From 

 81.0 to 85.3 f /(: of the fish released from 15 March 

 through 15 June were recovered. Only 58.5 and 

 59.5 f 7f of the fish released on 14 July and 15 August, 

 respectively, were recovered in the trap as migrants. 

 Presumably the remainder were residuals in the 

 ladder. 



In 1 97 7, recovery of both migrants and nonmigrants 

 from all groups was lower than in 1978 (Table 1), 



although the extent of migration of fish released near 

 the time of maximum migration tendency on 11 May 

 and 3 June was 8 1.5 and 85 c /'c, respectively, similar to 

 that observed for most release groups in 1978. Few 

 residual chinook salmon from releases before August 

 1977 were found when the ladder was drained in 

 January 1978. Nonmigrant fish were recaptured in 

 increasing numbers from releases from 12 July on. 



Size and Growth Relationships 



Growth rates of juvenile chinook salmon reared at 

 Round Butte Hatchery were 0.046 and 0.058 cm/d 



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