of 2,000 fish migrate up the Teslin River, trib- 

 utary to the Yukon River below LaBerge Lake, 

 and continue 72 km. into Teslin Lake before 

 entering the Nisutlin River ; from here the fish 

 continue for another 153 km. to a spawning 

 area at the outlet of Nisutlin Lake. 



IMPLICATIONS OF PRESENT RESEARCH 



Our experiments indicated that adult fall- 

 run Chinook salmon can migrate through large 

 impoundments. This ability apparently does 

 not require previous reservoir experience in 

 the juvenile stage; adult salmon returning up- 

 stream through Brownlee Reservoir in 1958-60 

 had passed downstream through this area as 

 juveniles when it was still a river. The results 

 point to the feasibility of passing adult chinook 

 salmon directly through large storage reser- 

 voirs, thus eliminating the need for extended 

 transport around impoundments. 



The successful passage of fall chinook sal- 

 mon through Brownlee Reservoir has special 

 significance because the environment for the 

 survival of upstream migrants is perhaps as 

 poor as any found in the present freshwater 

 range of this species. Surface temperatures 

 over 21° C. are common in the reservoir until 

 mid-September, and oxygen concentrations in 

 the deeper, cooler water generally are 4 p. p.m. 

 or less 11 during the fall migration. Despite 

 the marginal environment for survival of sal- 

 monids in the reservoir, adult migrants appar- 

 ently suffered no greater losses than the fish 

 bypassed upstream to the river, where water 

 temperatures and oxygen concentrations were 

 much more favorable. 



"Ebel. Wesley J., and Charles H. Koski. Physical and chemical lim- 

 nology of Brownlee Reservoir. Bureau of Commercial Fisheries BioloEical 

 Laboratory, Seattle. Wash. Manuscript in preparation. 



CONCLUSIONS 



The studies on chinook salmon in the Brown- 

 lee Reservoir area support the following 

 conclusions : 



1. Evidence of successful passage by chinook 

 salmon through Brownlee Reservoir and of 

 their sustained migration through large lakes 

 in Alaska, British Columbia, and Yukon Terri- 

 tory suggests that the large size of an im- 

 poundment may not be detrimental to upstream 

 migration of this species. 



2. Despite initial disorientation, chinook sal- 

 mon released in the reservoir were able to reach 

 spawning areas as successfully as those trans- 

 ported and released in the river above the im- 

 poundment. In the river, fish resumed migra- 

 tion shortly after release. 



3. The ability of fish to spawn successfully 

 was not affected by passage through the 

 reservoir. 



4. Ancestral spawning grounds in the Snake 

 River above the reservoir continued to be used 

 after the impoundment was formed. 



LITERATURE CITED 



Bryant, Floyd G., and Zell E. Parkhdrst. 



1950. Survey of the Columbia River and its tributaries 

 — Part IV. Area III Washington streams from the 

 Klickitat and Snake Rivers to Grand Coulee Dam, 

 with notes on the Columbia and its tributaries above 

 Grand Coulee Dam. [U.S.] Fish Wildl. Serv., Spec. 

 Sci. Rep. Fish. 37, 108 pp. 

 Fish, Frederick F., and Mitcheli, G. Hanavan. 



1948. A report upon the Grand Coulee fish-maintenance 

 Project, 19.39-47. [U.S.] Fish Wildl. Serv., Spec. 

 Sci. Rep. 55, 63 pp. 

 Johnson, James H. 



1957. Sonic tracking of adult salmon at Bonneville 

 Dam, 1957. U.S. Fish Wildl. Serv., Fish. Bull. 60: 

 471-485. 

 Parker, Lewis P., and Harry A. Hanson. 



1944. Experiments on transfer of adult salmon into 

 Deer Creek, California. J. Wildl. Manage. 8: 192-198. 



CHINOOK SALMON PASSAGE THROUGH BROWNLEE RESERVOIR 



45 



