BRISTOL BAY AND ALASKA PENINSULA SALMON STATISTICS 69 



previous to 1919, and a distinctly larger spawning escapement certainly is called for 

 if further depletion of this region is to be prevented. 



On the eastern side of Bristol Bay the situation does not appear to be so serious. 

 It seems useless to try to give separate consideration to the Kvichak, Egegik, and 

 Ugashik districts on account of the high degree of correlation, which we have shown 

 exists between the catches in these three localities. If the correlation in catches at 

 five-year intervals holds for 1928, we would expect the run of the coming season to be 

 correlated largely with that of 1923, which was a very good year in the Kvichak 

 district and about average in both Egegik and Ugashik. The year 1922, from the 

 runs of which the 6-year fish of 1928 will come, was also an excellent year, but 1924 

 was relatively poor. So far as this evidence goes, then, it would appear that the com- 

 ing season on the eastern shore of Bristol Bay ought to be good. The trend of the 

 catches here has been slightly downward, but it would not appear from this that a 

 serious deficiency would occur in 1928, The escapment to the Kvichak in 1923, as 

 indicated by observations on the spawning grounds, was exceptionally poor, however, 

 in spite of the good commercial catches.' The escapement of 1922 was excellent, and 

 if we had discovered a correlation between catches at six-year intervals it would 

 seem a favorable indication. As it stands, the evidence for the Kvichak is conflict- 

 ing, although on the whole it would appear to indicate a somewhat less favorable 

 year than 1927.'° 



In this general connection there is one other matter that seems worthy of mention, 

 and that is the remarkable association between climatic conditions and catches in 

 1926 and 1927. The winter of 1925-1926 was one of the warmest on record in Alaska, 

 as was also the summer of 1926. The winter of 1926-1927, on the contrary, was 

 exceptionally cold, and the summer of 1927 proved correspondingly cold and rainy. 

 It seems not beyond the bounds of possibility that there was some causal connection 

 between these conditions and the exceptionally heavy run of 1926 and the excep- 

 tionally light run of 1927. We know nothing of the factors, other than age and size, 

 that affect the sexual maturing of salmon, and it may be that temperature or condi- 

 tions associated with temperature during the winter months may affect materially 

 the percentage of flsh of a given age group that matures in a given year. A high tem- 

 perature may result in the maturing of a larger than normal percentage of the fish in 

 the ocean, while a low temperature may retard maturation. On some such basis as 

 this we might explain the large run of 1926 as due in part to the maturing of a large 

 number of fish that under normal conditions would not have matured for another 

 year; and the poor run of 1927 as due in part to the reduction of the stock by the 

 unusual maturing of fish in 1926 and in part to the retardation of maturation in a 

 large number of fish that normally would have matured in 1927. If this were so, we 

 might expect a rather better run than otherwise in 1928, due to the maturing of fish 

 retarded in 1927. This seems to be a rather remote possibility, it being more likely 

 that the fluctuations in salmon catch and weather conditions in 1926 and 1927 were 



' Alaska Fishery and Fur-Seal Industries in 1923. By Ward T. Bower. Appendii III, Report, U. S. Commissioner of 

 Fisheriesjfor 1924 (1925),^pp, 80>nd 81. Washington. 



1° Since this report went to press, the 1928 salmon runs in Bristol Bay have proved to be of considerably greater proportions than 

 our data indicated. We have discussed above some of the possible causes that may upset any prophecy based on such data. With 

 such large probable errors as we have to deal with, close estimates of the size of salmon runs are Impossible, but it is our belief that 

 carefully considered estimates of this kind will, in the long run, be justified.— W. H. E., July 17, 1928. 



