spawn in intermediate and large tribu- 

 taries and in middle reaches of the main 

 stem. 



Spring- run chinook salmon spawn in sonne 

 lower Columbia River tributaries such as 

 the Willamette, Cowlitz, and Kalama Rivers. 

 They also are distributed in middle tributaries 

 of the Columbia and Snake Rivers. (Fall-run 

 chinook salmon, discussed later in the report, 

 share spawning grounds in some sections of 

 the Cowlitz and Kalama Rivers.) These are 

 not all of the areas in which such duplications 

 occur but are cited as examples. 



French and Wahle (1960, 1965) observed 

 that some spring- run chinook salnnon spawned 

 in the same areas as the summer-run chinook 

 salmon in the middle Wenatchee and Methow 

 Rivers. Summer-run chinook salmon were 

 more numerous in the lower and middle 

 Wenatchee and Methow Rivers, whereas 

 spring- run chinook salmon were found prin- 

 cipally in the tributaries and upper parts of 

 these rivers. The examples are typical of the 

 spawning distribution of spring- and summer- 

 run chinook salmon in tributaries of the 

 Columbia River. 



In referring to the major sections of the 

 Columbia River drainage, I have defined the 

 lower Columbia River as the area below 

 McNary Dam, the middle Columbia River as 

 the area between McNary and Chief Joseph 

 Dams, and the upper Columbia as the area 

 above Chief Joseph Dam. Former or past 

 spawning areas are those known to have been 

 used before 1965. Present spawning areas are 

 those that were still in use in 1966. 



Map 1 shows the approximate location of 

 present and former spawning areas of spring 

 and sunnmer chinook salmon in the Columbia 

 River. The Willamette River, the principal 

 tributary of the lower Columbia, has an ex- 

 tensive tributary system with many excellent 

 spawning grounds (map 2). 



Table 2 lists the length of streams in kilo- 

 meters and distance of the stream from the 

 mouth of the Columbia or of the contributing 

 drainage. The table also indicates present and 

 former principal spawning areas and carries 

 notes on special features of the tributaries or 

 runs. 



Spring- and summer- run chinook salmon 

 formerly migrated almost the entire length 

 of the Columbia River (map 1 ). Fronn informa- 

 tion obtained from residents of the upper 

 Columbia River area in 1936, Bryant and 

 Parkhurst (1950) reported that large chinook 

 salmon (probably summer- run), weighing from 

 18 to 27 kg., migrated nearly 1,932 km. up 

 the Columbia River to spawn in the main 

 stem just below the outlet of Windermere 

 Lake in British Columbia. After the construc- 

 tion of Grand Coulee Dam, runs were inter- 

 cepted at Rock Island Dam (1939-43) for 

 transplanting into the Wenatchee, Entiat, 

 Methow, and Okanogan Rivers. 



Migrations of spring- run chinook salnnon 

 into the upper Snake River were documented 

 by Evermann (1896). Spring- run chinook 

 salmon were observed spawning as far 

 upstream, as Rock Creek, a tributary that 

 enters the Snake River just below Augur 

 Falls--a distance of more than 1,442 km. 

 from the ocean. The runs that migrated into 

 Rock and Salmon Falls Creeks and into the 

 Bruneau River were depleted or lost many 

 years ago because of inadequate or no provi- 

 sions for fish at irrigation dams and diver- 

 sions . 



In summary, some of the more obvious 

 factors responsible for the destruction of 

 spawning and rearing areas for spring and 

 summer chinook salmon in the Columbia 

 Basin are: (1) reduction of stream flow and 

 blockage by irrigation projects and splash- 

 dams; (2) blockage by hydroelectric proj- 

 ects; (3) inundation of spawning areas by im- 

 poundments; and (4) destruction of spawning 

 and rearing areas by siltation, debris, or 

 pollution fronn sewage, farming, logging, and 

 mining. 



Abundance of Spring- and Summer-Run 

 Chinook Salmon 



Commercial salmon fishing in the Columbia 

 River initially was confined almost solely to 

 the spring and summer runs of chinook salmon. 

 The size of the catch (up to nearly 19.5 million 

 kg.), the extent of the fishery, and the reports 

 by early settlers of the large runs observed 

 in nearly all of the accessible tributaries 

 attest to the magnitude of these stocks during 

 the early Columbia River salmon fisheries. 

 Inevitably, the runs began to decline as major 

 upriver producing areas were cut off because 

 of factors previously mentioned. 



Some of the more important spawning areas 

 of spring- and summer-run chinook salmon 

 no longer in production include: (1) Lower 

 Columbia tributaries- -major portions of the 

 John Day and Umatilla Rivers; (2) Snake River 

 tributaries - -most of the Clearwater and 

 Powder Rivers; all of the Burnt, Weiser, 

 Malheur, Payette, Owyhee, Boise, and Bruneau 

 Rivers; and all of the Salmon Falls and Rock 

 Creeks; (3) middle and upper Columbia tribu- 

 taries--the nnajor portion of the Walla Walla 

 River system, considerable area in the Yakima 

 and Okanogan Rivers, and the entire area 

 above Chief Joseph Dam (including the main 

 stem Columbia, the San Poil, Spokane, Kettle, 

 Pend Oreille, and Kootenay Rivers). 



In a report prepared for a hearing on regu- 

 lations for commercial salmon fisheries of 

 the Columbia River (Fish Commission of 

 Oregon and Washington State Department of 

 Fisheries, 1967), the fishery agencies of 

 Washington and Oregon provide current esti- 

 mates of the size of spring and summer runs 

 of chinook salmon. These estimates (table 3) 



