648 
BULLETIN OF THE BUREAU OF FISHERIES 
RED SALMON 
The red salmon of this district are derived almost exclusively from the Chignik 
River. It is possible that a few fish, especially of those caught in Aniakchak Bay, 
come from smaller streams near by, but the Chignik runs dominate so largely that 
we have considered the total catch of the district as a unit and refer it exclu- 
sively to the Chignik River. Figure 2 shows graphically the total annual catches of 
red salmon. It will be seen that the fishery shows much the same history as some of 
the districts discussed in Part I; namely, a period of gradual growth to a maximum 
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Figure 2. — Catch of red salmon at Chignik 
which is maintained for a time but is eventually followed by a drop in productivity 
and the incidence of wider fluctuations which are indicative of depletion. The 
lowered level of productivity since 1924 is due in part to the regulations which have 
required an increased escapement as measured by the weir count. Such an increased 
escapement was necessary to prevent further depletion and to provide for the 
upbuilding of the run to the level of greatest productivity, but it has, necessarily, 
decreased the commercial catch. As the runs build up to a more healthy state the 
Figure 3. — Percentage fluctuation from the trend of the catch of red 
salmon at Chignik 
commercial catch will naturally increase again, and it may be presumed that, as 
conditions warrant, some of the present restrictions can be gradually removed. 
It is interesting to note the character of the deviations from the trend shown by 
the Chignik catches. The trend shown in Figure 2 has been calculated in the same 
way as the trends in the previous report and represents a moving average by fives. 
(See p. 61, Part I.) Figure 3 shows the percentage deviations from this trend. A 
comparison with the similar graphs (showing the percentage deviations from the trends 
