84 BULLETIN OF THE BUREAU OF FISHERIES 



The two most important localities, especially as regards the catch of red^almon, 

 are Ikatan and Morzhovoi Bays. The tagging experiments of 1922 and 1923 " 

 showed that the nms of red salmon in these two bays were intimately associated, 

 not only with one another but with the runs of Bristol Bay. It was apparent that 

 there was a considerable interchange of fish between Ikatan and Morzhovoi Bays, 

 and that important percentages of the fish from both localities went ultimately to 

 Bristol Bay. It was shown further that the traps located on the east side of Morzho- 

 voi Bay caught a smaller percentage of Bristol Bay fish and a correspondingly larger 

 percentage of red salmon derived from local spawning streams along the southern 

 shore of the Alaska Peninsula than did the traps on the west side of the bay. On 

 this accoimt it would be desirable to separate the catches made on the east and west 

 sides of this bay, but it has been impossible to do this with the data at hand. In 

 view of the close association between the red-salmon runs in Ikatan and Morzhovoi 

 Bays we have combined the catches for the purpose of analysis, and the data are 

 presented graphically in Figure 14. 



The trend of the total catch increased consistently up to 1922, but since that 

 year has fluctuated rather widely, although the general tendency seems to be down- 

 ward. We can not say whether this downward tendency is due to the restrictions 

 imposed during the past four seasons or whether it is a reflection of the general 

 downward trend that has been demonstrated in the Bristol Bay catches for the past 

 few years. It seems probable that both factors may have had their effect. 



It is quite clear from Figure 14 that the fluctuations in Morzhovoi Bay have been 

 proportionally greater than those in Ikatan Bay, the poor years being relatively 

 much poorer at Morzhovoi than at Ikatan. It has been suggested that in j'ears 

 marked by poor runs a smaller percentage of the fish enter Morzhovoi Bay. It is 

 as though the mass of fish passing along the southern shore of the peninsula kept to 

 the more direct routes for Ikatan Bay and False Pass in the poor years, while on 

 the good j'ears the relatively greater mass of fish tended to crowd large numbers off 

 the direct route and into such side branches as Morzhovoi Bay. The available 

 evidence lends some weight to such an hypothesis. 



On account of the proved relationship between the red-salmon runs in Ikatan 

 and Morzhovoi Bays and those of Bristol Bay we have been interested to learn to 

 what extent the catches at Ikatan and Morzhovoi Bays are correlated with the catches 

 in Bristol Bay. Figure 15 shows the percentage deviations of the red-salmon catches 

 from tlie trend as compared with the similar data for Nushagak and Kvichak and 

 for Bristol Bay as a whole. The Pearsonian coefficients of correlation for three com- 

 binations are as follows: 



Ikatan-Morzhovoi and Nushagak +0. 163 ±0. 181 



Ikatan-Morzhovoi and Kvichak +.814 ±.063 



Ikatan-Morzhovoi and Bristol Bay +.792 ±.070 



The high correlation between the Ikatan and Kvichak catches leaves little doubt 

 that the Kvichak fish form by far the most important element in the catch at Ikatan. 

 The lack of correlation with Nushagak is doubtless due to the dominating influence 



" Gilbert, footnote 12, p. 74. Second Experiment in Tagging Salmon in the Alaska Peninsula Fisheries Eeservation, Summer 

 of 1823. By Charles H. Gilbert and Willis H. Rich. Bulletin, U.S. Bureau of Fisheries, Vol. XLII, 1926 (1927), pp. 27-76. Wash- 

 ington, 1925. > 



