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BULLETIN OF THE BUREAU OF FISHERIES 



of the much larger run of Kvichak fish ; in the period 1911 to 1927 the catch of salmon 

 on the Nushagak side averaged only 23. S per cent of the total for Bristol Bay. It 

 does not appear probable that either the Kvichak or the Nushagak fish appear in the 

 runs south of the peninsula in materially different proportions than in Bristol Bay. 

 This is borne out by the results of the tagging experiments in 1923; 11.5 per cent of 

 the tags recovered in Bristol Bay that year were taken on the Nushagak side, and 

 the catch at Nushagak for the season was 10.5 per cent of the total for Bristol Bay. 

 These facts indicate strongly that the red salmon of the Ikatan district are composed, 

 in large part, of a mixture of Bristol Bay fish, in which each run is proportionally 

 represented. One would anticipate, if this be true, that the correlation between 

 Ikatan and Bristol Bay as a whole would be greater than the correlation between 

 Ikatan and any one of the units. In fact, the correlation with Kvichak is slightly 

 higher, but the difference is so small that it can have no possible significance. 



Fig. 15. — Percentage fluctuations in the catch of red salmon at Ikatan compared with those in Bristol Bay 



An interesting possibility suggests itself as a result of this intimate correlation 

 between the catches of red salmon at Ikatan and Bristol Bays and in view of the fact 

 that the fish require about two weeks in which to make the journey between the two 

 regions. It should be possible to determine from the run of fish at Ikatan what may 

 be expected in Bristol Bay later in the season. To do this with any accuracy would 

 involve a careful comparative study of the daily catches in both places, with particu- 

 lar reference to the reliability (as measured by the probable error) of determinations 

 of the Bristol Bay run based on the accumulated totals of catches at Ikatan on various 

 dates during the season. If such an analysis should prove accurate within reasonable 

 limits, it might have some very interesting and practical applications. 



Relative to the catches of other species of salmon, there does not seem to be any 

 material correlation between the catches taken in Ikatan and Morzhovoi Bays 

 except that due to the simultaneous development of the fisheries and other economic 

 factors. Therefore, we shall consider them as separate units in the following discus- 

 sions of the various localities in the Ikatan district. 



