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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



f/^y CLARK LAKE 



• ^ 



Figure 1. — Kvichak River system : one of the principal spawning areas for red salmon in the Bristol Bay region of 



western Alaska. 



The Kvichak-Niiknek district is one of several 

 areas in Bristol Bay in which commerical fishing 

 is permitted. The fishery came into large pro- 

 duction at the turn of the century. Continuous 

 catch and pack records since that time show tre- 

 mendous fluctuations in abundance of red salmon 

 from year to year. These fluctuations have 

 formed a cyclic pattern with peak catches usually 

 occurring every 4 or 5 years. From 1910 to 1958, 

 the average annual catch was 9 million fish. The 

 peak catch was taken in 1938 when 21 million red 

 salmon were supplied to local canneries. Since 

 1938, however, the cycles tended to decline, and 

 the catch reached a 60-year low of 923,000 fish in 

 1958. 



Accurate estimates of escapements into the 

 Kvichak River system are lacking for the years 

 prior to 1955. In only one year was the entire 

 escapement counted : in 1932, when the Bureau of 



Fisheries passed 5,065,000 salmon through a weir 

 on the upper river (U.S. Bureau of Fisheries, 

 1933). Continued enumeration by weirs proved 

 impractical because of excessive costs of construc- 

 tion and maintenance, hence, their use was 

 discontinued. 



Catches have been used in some areas as indices 

 to escapements. But catches in the Kvichak- 

 Naknek district include fish destined for the 

 Kvichak, Nalmek, and Alagnak Rivers, and to a 

 lesser extent, the Egegik River. In addition, year- 

 ly changes in the distribution of gear, the intensity 

 of the fishery, and contributions of the various 

 runs, all vary the relation between catch and es- 

 capement. For these reasons, the catches are poor 

 indices to red salmon escapements up the Kvichak 

 River. 



Estimates of the numbers of salmon on the 

 spawning grounds, obtained from aerial surveys. 



