FISHERY BULLETIN: VOL. 71, NO. 2 



returns to the hatchery concomitant with 

 greater returns to the fishery. 



The information we have to date is sufficient 

 to consider the feasibility of a major collection 

 and transportation system on the Snake and 

 Columbia Rivers. An evaluation of a prototype 

 system was initiated at Little Goose Dam on 

 the Snake River in the spring of 1971. The 

 results of that study, we believe, should lead 

 to a determination of whether collection and 

 transportation of juvenile salmon and trout is, 

 indeed, feasible and can provide substantial 

 protection for runs from upriver areas. 



CONCLUSION 



1. The homing of adult fish that were cap- 

 tured during their seaward migration as juve- 

 niles and then transported (from upstream of 

 Ice Harbor Dam to below Bonneville Dam) 

 downstream was not reduced by the trans- 

 portation operation. A comparison of the trans- 

 port/control ratios of returning adults in the 

 lower river with those at Ice Harbor Dam 

 and the spawning grounds indicated that no 

 loss to the transport groups occurred between 

 the estuary. Ice Harbor Dam, and the spawn- 

 ing ground. Straying of either the transported 

 or control groups was not indicated in surveys 

 of hatcheries and spawning grounds. 



2. Data from adult returns indicated that 

 transportation of naturally migrating juvenile 

 spring- and summer-run chinook salmon and 

 of steelhead trout from upstream of Ice Harbor 

 Dam to below Bonneville Dam definitely in- 

 creased returns (50-300% ) to the fishery and 

 to Ice Harbor Dam, depending on the river 

 environment during the time of transport. 



3. Transportation of juvenile spring chinook 

 salmon to the release site below John Day 

 Dam did not increase their survival (as evi- 

 denced by adult returns) during the period 

 before the dams began heavy spilling but did 

 increase survival about 15% after heavy spilling 

 began. 



4. The juvenile population of chinook salmon 

 migrating seaward past Ice Harbor Dam from 

 12 April to 13 May in 1968 was of mixed 

 seasonal races — with juvenile summer and 

 spring chinook salmon mixed and evenly dis- 



persed throughout the period. After 13 May, 

 about 70% of the juvenile chinook salmon were 

 summer-run fish. 



5. Quality of brands on adult fish that had 

 been marked as juveniles (using tools that 

 were chilled with liquid nitrogen) varied be- 

 tween species — 38% of the marks on spring 

 and summer chinook salmon were legible com- 

 pared with 64% on steelhead trout. 



6. Relative effects of transport over controls 

 is demonstrated, but effects of handling on 

 both groups has not been evaluated. Thus, 

 the survival of transported fish needs to be 

 compared with survival of undisturbed mi- 

 grants and is currently being studied. 



ACKNOWLEDGMENTS 



The authors wish to thank the fishery biolo- 

 gists from the Fish Commission of Oregon, 

 the Washington Department of Fisheries, and 

 the Idaho Fish and Game Departments, who 

 assisted in recovering tags from adults in the 

 commercial and sport fisheries and the spawn- 

 ing grounds. We also wish to thank Paul 

 Winborg, Project Engineer, U.S. Army Corps 

 of Engineers, at Ice Harbor Dam for his 

 patient cooperation during this continuing 

 experiment. 



LITERATURE CITED 



BEimNGEN, K. T., AND W. J. Ebel. 



1970. Effect of John Day Dam on dissolved nitro- 

 gen concentrations and salmon in the Columbia 

 River, 1968. Trans. Am. Fish. Soc. 99:664-671. 

 Bentley, W. W., and H. L. Raymond. 



1969. Passage of juvenile fish through orifices in 

 gatewells of turbine intakes at McNary Dam. 

 Trans. Am. Fish. Soc. 98:723-727. 

 Bergman, P. K., K. B. Jefferts, H. F. Fiscus, and 

 R. C. Hager. 



1968. A preliminary evaluation of an implanted, 

 coded wire fish tag. Wash. Dep. Fish., Fish. 

 Res. Pap. 3(l):63-84. 



Durkin, J. T., W. J. Ebel, and J. R. Smith. 



1969. A device to detect magnetized wire tags 

 in migrating adult coho salmon. J. Fish. Res. 

 Board Can. 26:3083-3088. 



Ebel, W.J. 



1969. Supersaturation of nitrogen in the Columbia 

 River and its effect on salmon and steelhead 

 trout. U.S. Fish Wildl. Serv., Fish. Bull. 68:1-11. 



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