104 FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



report that treats of the 1938 run and to present it as a separate publication. For this 

 purpose the data presented in the original report of the board of consultants have been 

 supplemented by data that have become available since the original report was pre- 

 pared. At that time no catch data were available later than the close of the "spring" 

 fishing season on August 25. In this revision the catch data for the "fall" season also 

 have been included. Various omissions and minor changes have been made, and some 

 additional analysis is given. 



Acknowledgment is due the Bureau of Reclamation and the writer's associates on 

 the board of consultants for permission to use here the material of the original report. 

 Acknowledgment also is due the Washington Department of Fisheries, the Fish Com- 

 mission of Oregon, the United States Army Engineers, and the Bureau of Reclamation 

 for many data used in the original report and in this revision. 



THE COLUMBIA RIVER SALMON FISHERY 



Five species of salmon are taken in the commercial fishery on the Columbia 

 River. These are (1) chinook salmon (Oncorhynchus tschawytscha) , (2) silver salmon 

 (0. kisvtch), (3) blueback salmon (0. nerka), (4) chum salmon (0. keta), and (5) steel- 

 head trout (Salmo gnirdnerii) . 



Fishing is permitted throughout the year except during March and April, and 

 during the period from August 25 to September 10. The open season from May 1 to 

 August 25 is spoken of as the spring season, and that from September 10 to March 1 

 as the fall season. Comparatively few fish are taken during December, January, and 

 February, however, so that the fall season is practically limited to the period from 

 September 10 to about the end of November. In addition to these seasonal closed 

 periods there is a weekly closed period extending from 6 o'clock Saturday evening until 

 6 o'clock Sunday evening, effective during the spring open season. 



Because the estimate of the intensity of the fishery is based on the ratio of the 

 commercial catch to the fish passing Bonneville Dam, it is important to consider the 

 relative extent of spawning which, for each species, takes place above and below this 

 point. Obviously, if a large proportion of the fish of any one species, population, or 

 group of populations spawns below Bonneville Dam, estimates of relative spawning 

 escapement based upon the number of fish passing Bonneville will be in error. 



Practically all the bluebacks spawn above Bonneville. As is well known, their 

 habit is to spawn only in lakes or the tributaries of lakes in which the young remain 

 for 1 or more years before making the seaward migration, and no lakes typical of those 

 in which bluebacks spawn are to be found in the tributaries of the lower Columbia. 



The chinooks spawn in nearly all the accessible tributaries of the river, both above 

 and below Bonneville; a fact certain to lead to some error. With one exception, 

 however, this error is probably negligible during the main part of the run because it is 

 chiefly the late fall fish that spawn in tbe lower tributaries. The exception is the 

 considerable run of chinooks that ascends the Willamette River in April and early May. 

 There are, unfortunately, no reliable estimates of the extent of this run, but it forms 

 the basis for an extensive sport fishery in the Willamette River, especially just below 

 the falls at Oregon City. No commercial fishing is permitted in tbe Willamette 

 River itself and the peak of tbe rim is ordinarily past Oregon City by the opening of 

 the season on May 1. Although some of these Willamette River chinooks are un- 

 doubtedly taken in the commercial fishery in the Columbia below the mouth of the 

 Willamette, it does not seem likely that these constitute a large percentage of the total 



