There is urgent need to reduce the possibility of large percentages 

 of blueback salmon being isolated by construction of high dams such as thf; 

 proposed Priest Rapids Dam situated between Rock Island and McNary Dams, 

 or injured and delayed aj; at McNary Dam and at Dryd.en and Tumwater Dsjns 

 during low-water periods. Tliis could be accomplished by surveys and ex- 

 ploratory planting of young bluebacks to detenriine what other lakes and 

 streams may be utilized for blueback salmon spawning in the event that 

 those presently in use should become isolated by river utilization for 

 other purposes. 



With the present increase in the runs,, larger numbers of young fish 

 are available for experimental planting, A possibility for a test of 

 this kind would be the Yakima system where blueback rims have been elimi- 

 nated by lack of fishways and fish screens at water diversions — conditions 

 which have since been improved by extensive construction of these devices. 

 In the Yalcima system such lakes as Keechelus^ Kachess, Cle Eluia, and 

 Bumping are reported to have been at one time natm-al reai'ing areas for 

 bluebacks. These lakes are presently dammed at their outlets and used for 

 water storage. The v/ater is released in accordance with irrigation demands o 

 Tne most readily adaptable of these is Bumping Lake which has a l45-foot dam 

 and a reasonably constant year-round flew. It is possible that alterations 

 of flow regulation (such as those proposed for the Trinity River, California, 

 Noffett and Smith 1950, p„ ?8) could be made in one or two of the other lai<es 

 to make them suitable for blueback salmon. 2/ (These f low r egulations and 

 related teraperat-ores will be studied further.,) A planting of Mupbacks in 

 Bumping Lake was made in 19Ji2 with a recovery of 0,008 percentiS/ from a 

 25,COC-fish planting as shown by returns of marked individuals. It is felt 

 that more experiments shoula be conducted in Biomping Lake, as well as some 

 in other lakes » If a good return were experienced, the bluebacks could be 

 trapped and hauled over Biimping Lake Dam until proper fishways were warranted. 



Another possibility is Palmer Lake which is on the Similkameen River, a 

 tributary of the Okanogan River. Six miles from its confluence with the 

 Okanogan River, the Similkameen River has a power dam 65 feet high that has 

 never been equipped Trdth a fishway. PaLner Lake lies farther upstream but 

 is all within the United States and has l^een regarded as being well adapted 

 to the production of blueback salmon, ii^ 



2/ The level of abundance of the Yakima River anadromous-fish populations 

 could be raised substantially if adequate flows were provided during periods 

 of fish migrations if certain improvements were made to fishways at Prosser, 

 Sunnyside and Wapato Dams, and if certain other improvements in the interest 

 of fish life were effected, (Corps of Engineers 19u8, p, 68). 

 10/ This extremely low percentage of recovery could well be a rei-ult of in- 

 troducing Quinault sockeye salmon which are not endemic to the Columbia River 

 system, 



11/ "A report of the pr'sliminary investigations into the possible methods 

 of preserving the Coiiombia River salmon and steelhead at the Grand Coulee 

 Dam." Mimeographed report by the Vfeshingtcn State Department of Fisheries, 

 121 pp, January 19l8. 



27 



