FISHERY BULLETIN: VOL. 71, NO. 3 

 Table 4. — Comparison of size and condition of migrating salmon with salmon in reservoir population. 



' From Figures 12, 13, and 14; mean is for midpoint of sampling period. 



- Taken between 2/27/62 and 5/27/62. 



3 Taken 5/7/63. 



"* By extrapolation of Figure 12. 



salmon left when temperatures were 11° to 

 14.5°C, and spill was 0.014 to 0.056 ma/s 

 (0.5to2cfs). 



CONCLUSIONS 



The high productive capacity of the reservoir 

 was seen in the rapid growth, high condition 

 factor, and high net production achieved during 

 the summer by planted chinook salmon. High 

 mortalities were caused primarily by predation. 

 Severe summer conditions also caused deaths, 

 indicating that the reservoir and others similar 

 to it in thermal and chemical qualities should 

 be considered marginal for use in natural rear- 

 ing of salmon smolts. 



Emigration by salmon was limited, but indi- 

 cated that substantial voluntary movement may 

 occur at appropriate temperatures and outflows, 

 and that migrations by both age classes I and 

 II including fish in excess of 100 g in weight are 

 possible. 



ACKNOWLEDGMENTS 



The authors wish to express their apprecia- 

 tion to the following who assisted in the prep- 

 aration of this manuscript: Jay B. Long di- 

 rected field operations in summer 1961. James 

 Shelton advised on field work and assisted dur- 

 ing transplanting operations. John Edgington, 

 David Vincent, and other students assisted in 

 field and laboratory work. Donald W. Chapman 

 helped interpret the biological data. James D. 

 Hall, John R. Donaldson, and Anthony J. Ghar- 

 rett reviewed the manuscript. 



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890 



