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Fishery Bulletin 101(2) 



of 70% of the individual fish correctly assigned to specific 

 populations. Correct assignment to region of origin was 

 achieved for at least 80% of the chinook salmon from all 

 regions; the highest rates were for the Birkenhead River 

 and three Thompson River regions, and the lowest rates for 

 the middle and upper Fraser regions. 



Application to a coded-wire tag (CWD sample 



CWTs were available from seven Fraser River populations 

 caught in marine fisheries. The average error of the esti- 

 mated percentage for the seven populations present was 

 2% per population for the 83-fish sample estimated with a 

 50-population baseline (Table 61. Tags recovered from the 

 upper Adams River population were combined with the 



lower Shuswap River because the Upper Adams fish were 

 recent transplants from the Lower Shuswap River popula- 

 tion. Similarly, tags recovered from the Stave River popu- 

 lation were combined with the Harrision River population 

 because the Stave River fish were recent transplants from 

 the Harrison River. The average error of the estimated per- 

 centage for the five regions present was 1.4%. The accuracy 

 of estimated stock compositions obtained from analysis of 

 the CWT sample were within the range expected based 

 upon the analysis of the simulated mixtures. 



Lower Fraser commercial net fishery 



Estimation of stock composition in the lower river commer- 

 cial net fishery is of key local fishery management interest, 



