LANDER and HENRY: 1965-66 BROOD COHO SALMON 



Table 8. — Tests of the hypothesis that recoveries of 1965-66 brood coho salmon in 

 ocean troll and sport fisheries are independent of hatcheries of origin. Chi-square 

 was tested at the 95% level. 



' LR — number of Lower River mark (Ad-RM) recoveries. 

 2 UR = number of Upper River mark (Ad-LAA) recoveries. 



Distribution by Ocean Commercial 

 and Sport Fisheries 



It also is possible to compare the recovery of 

 marks from the Lower River (Ad-RM) and the 

 Upper River (Ad-LM) hatcheries in the ocean 

 commercial and sport fisheries for the different 

 states. This is done in Table 8 for both the 1965- 

 66 broods by means of Chi-square tests. The 

 commercial fishery usually operates farther 

 from shore than the sport fishery, so the analysis 

 also may test differences in offshore distribu- 

 tion between these two marks. In Table 8 we 

 see the hypothesis of independence is rejected 

 for the Washington fisheries for both brood 

 years. In other words, the recovery of marks in 

 the Washington commercial and sport fisheries 

 was different for these two groups of marked 

 coho salmon for both brood years. For Oregon, 

 on the other hand, the differences were not 

 significant for either brood year. For California 

 recoveries, the difference in the recoveries 

 between the two marks and two fisheries was 

 significant for the 1965 brood but not for the 

 1966 brood. As was pointed out earlier, it was 

 these 1965 brood recoveries of Ad-RM marks in 

 California which showed the high percentage 

 recovery in Figure 4. To summarize these 

 analyses, the two marks (Ad-RM; Ad-LM) 



showed no significant difference in recoveries 

 in the Oregon ocean sport and commercial 

 fisheries, were significantly different for the 

 Washington fisheries, and were significantly 

 different for the 1965 brood for the California 

 fisheries. This suggests a definite differential 

 distribution pattern north of the Columbia for 

 both broods and also a differential distribution 

 pattern south of the Columbia River, at least 

 for the 1965 brood fish. 



Distribution by Time 



The Upper River (Ad-LM) and Lower River 

 (Ad-RM) mark recoveries also can be examined 

 to see if the data indicate any difference in time 

 of recovery in certain fisheries. In Table 9 are 

 listed the calculated seasonal recoveries (in per- 

 cent) for selected ports along the Pacific coast. 

 In general, data for most of the ports not listed 

 either showed a similar pattern or had insuf- 

 ficient sampling data for this analysis. 



The data listed in Table 9 clearly indicate that 

 there was a definite difference in timing between 

 these two groups of fish for both the British 

 Columbia and Washington recoveries for both 

 brood years, the Upper River fish (Ad-LM) dis- 

 appearing first from the ocean fisheries. This 

 difference in time of capture also persisted for 



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