8 



BULLETIN OF THE BUREAU OF FISHERIES 



Figure 7 shows graphically the annual catches from 1896 to 1926, both inclusive, 

 broken up into five-year cycles, of which there are six complete cycles and a seventh 

 just beginning with 1926. No attempt was made to include the data for the years 

 previous to 1896, as these data obviously are not comparable with those since that 

 date. During the first few years (from 1882 to 1888) the industry was growing rap- 

 idly, and during the years from 1888 to 1895 it profited from the intensive exploi- 

 tation of a practically virgin field. Since then the annual runs have presented a 

 more or less regular sequence of events. 



to 

 o 



1906 



\ 



\ 



\ 















1901 

 1896 



\ 



X 



•s 



A - 



1 



\ 



\ 















1916 

 1926= 



\\ 



\ \ 













1911 

 1921 



— 



Vv \ 



\ 



/ 



/ 





1905 

 1900 



1910 







\ \ 

 \ 



N \ 



\ 7 



A I 



m 



MEAN 

 1920 

 1925 





\ 



\ 





\. 



y 



1915 





2 : 



\ 4 5 



YEAR OF CYCLE 



Fig. 7.— Catch of red salmon at Karluk in 5- year cycles, from 1896 to 1926 



The graph shows clearly the cyclic character of the runs of red salmon in the 

 Karluk River. Since the Karluk salmon are predominantly five-year fish, we 

 anticipate a correlation between the run of any year and that of the fifth year pre- 

 ceding, the fifth year following, etc. With the exception of one of the six cycles, it 

 is apparent from the graph that the Karluk runs consist of two good years followed 



