Table 8- — Average number of fall-run chinook salmon entering 

 sections of the Columbia River and its tributaries^ 



Stream 



Klaskanine, Grays, ELokomin, 

 Clatskanie Rivers, and Big and 

 Gnat Creeks _ 



Cowlitz River ■. 



Kalama River 



Lewis River 



Washougal River 



Tanner Creek (Hatchery) i . . . 



Eagle Creek ( " ) 



Herman Creek ( " ) 



Wind River 



Little White Salmon River 



Spring Creek ( Hatchery ) 



Big White Salmon River 



Hood River 



Klickitat River 



Columbia River, John Day 



damsite to McNary Dam 



Snake River: 



Main Snake, mouth to Salmon River 

 jxinction 



Main Snake from mouth of Salmon 



River to Oxbow Dam 



Main Snake above Brownlee Dam. . . . 



Columbia River, Pasco to Chief 



Joseph Dam 



Total 



Period 



{') 



1957-60 



1957-60 

 1957-60 



1957-60 



Nujiiber 

 of fish 



Thousands 



5 20 



6 8 



225 



Estimates of niunbers entering individual tributaries are 

 based on counts in spawning areas or numbers appearing at 

 hatchery racks. 



^ Period on which estimate is based. 



^ Specific years unknown. 



^ Intimates of population using this reach are based on 

 aerial surveys. 



^ Estimates based on apportionment of total run entering 

 Snake River. 



^ Counts at Oxbow and Brownlee Dams. 



sented in table 8 and map 6. (Streams having 

 estimated spawning populations of less than 

 1,000 fish are not included.) Average counts 

 of fall chinook salmon at Bonneville, The 

 Dalles, and McNary Dams were 163,000, 

 90,000, and 56,000, respectively, for 1957-60. 

 These counts were considered in estimating 

 runs above each dam. 



Runs to the uppermost spawning areas in 

 the Snake River have been greatly reduced in 

 recent years primarily because of the failure 

 of juvenile salmonids to pass through Brownlee 

 Reservoir. All fall chinook salmon bound for 

 spawning areas above Brownlee Reservoir are 

 now intercepted at the Hells Canyon damsite 

 and propagated artificially. The most important 

 production areas for fall chinook salmon, ac- 

 cording to average returns during 1957-60, 

 were as follows: (1) Snake River, (2) main 

 Columbia River from John Day to McNary 



Dams, (3) Spring Creek (hatchery production 

 only), (4) Cowlitz River, and (5) Kalama 

 River. 



SUMMARY AND CONCLUSIONS 



Irrigation, logging, mining, dam construc- 

 tion, and other activities have reduced the 

 productive capacity of many of the spawning 

 streams for chinook salmon throughout the 

 Columbia Basin. 



Much of the information contained in this 

 report on spawning is based on reports pub- 

 lished in 1948-50 by the Fish and Wildlife 

 Service. The data in the reports were ob- 

 tained by extensive surveys of the Columbia 

 River Basin which were started in 1934 by 

 the U.S. Bureau of Fisheries and continued 

 under the Fish and Wildlife Service until 1946. 

 Subsequent reports by both Federal and State 

 fishery agencies were used to obtain more 

 specific information on certain sections of the 

 Columbia River Basin. 



Cooperative Federal-State public works pro- 

 grams in the 1930's corrected conditions in 

 many problem areas by installation of fish 

 screens on water diversions, improvement of 

 fishways, and removal of logjams and splash- 

 dams. The Columbia River Fishery Develop- 

 ment Program (a Federal-State construction 

 and rehabilitation program started in 1949) 

 has restored productive areas, made new 

 areas available, and provided numerous hatch- 

 eries . 



The Columbia Basin has three runs of 

 chinook salmon- - spring, summer, and fall-- 

 based on the periods when the adults migrate 

 from the ocean to the river. Spring and sum- 

 mer runs dominated the catches until about 

 1928, when catches from the fall run be- 

 came larger. 



Adult spring-run chinook salmon start their 

 spawning migrations by entering the Columbia 

 River from February to mid-May and spawn 

 in smaller tributaries and upper reaches of 

 large streams from late July to late Septem- 

 ber. Summer-run chinook salmon enter from 

 June through mid-August and spawn in the 

 main stem and medium and large midriver 

 tributaries from mid- August to mid- 

 November. Fall- run chinook salmon enter 

 the Columbia River from August 15 through 

 October. They spawn from September to De- 

 cember in tributaries of the lower and middle 

 river; the main stem above The Dalles, 

 McNary, and Rocky Reach pools; and in the 

 Snake River from above Ice Harbor pool to 

 Hells Canyon damsite. 



Spring- and summer- run chinook salmon 

 now migrate in largest numbers to spawning 

 grounds of the Salmon River in Idaho and its 

 tributaries; these runs constitute 44 percent 

 of the recent (1957-60) Columbia River escape- 

 ments. Other tributaries having substantial 



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