Fishery bulletin of the Fish and Wildlife Service - NOAA

106 FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE
The catch, within the river does not, therefore, represent the entire productivity of the
runs of this species, but with available data it is not possible to determine with much
accuracy what this total productivity actually is. The constant decline of the last 20
years, however, taken in connection with data presented in this report, certainly
warrants the conclusion that the chinook runs are seriously depleted." We shall show
below that the present exploitation of these depleted runs is being conducted with an
intensity so great that it can only lead to disaster in the not far distant future unless
the present trends can be altered.
The blueback salmon catch for both of the first 2 periods shown in figure 1 is approximately
twice that of the succeeding periods, and there is some reason to think
that the abundance of blueback salmon previous to 1890 was at least the equal of that
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