FISHERY BULLETIN: VOL. 73. NO. 4 



fish to Youngs Bay were more or less detrimental 

 than the more natural migration pattern from the 

 hatchery through Bonneville Dam and down- 

 stream to the ocean. If the employed transportation 

 method caused significant mortalities and if 

 changes in the method can be made to improve 

 survival, then a better contribution from this type 

 of release procedure could be obtained. 



Other researchers have had similar difficulties in 

 evaluating groups of fish released at different 

 sites. Ellis and Noble (1960) had difficulty compar- 

 ing the contribution and survival of groups of 

 chinook salmon released at Klickitat Hatchery and 

 Skamokawa, Wash., 354 km (220) and 53 km (33 

 miles), respectively, from the Columbia River 

 mouth. Differences in the size of fish at release and 

 marks used on each group as well as generally poor 

 nutrition and survival during the hatchery rearing 

 period influenced the results. However, the catch 

 data indicate that contribution to the Columbia 

 River fisheries was increased by release site 

 manipulation. If straying could have been 

 evaluated, total survival for the transported group 

 may have been greater than the nontransported 

 fish. 



Wagner (1967, 1969) noted in studies with 

 various release sites for steelhead on the Sandy, 

 Alsea, and Wilson rivers that, in general, the con- 

 tribution of hatchery reared steelhead to the sport 

 fisheries was increased by releasing smolts in the 

 lower stream areas. Here again, different mark 

 types on the groups and variations in fishing ef- 

 fort on different stream sections may have 

 influenced the results. 



More recently Ebel et al. (1972) transported 

 chinook salmon around Snake and Columbia River 

 dams. They found that the contribution ratio of 

 transported versus nontransported fish in the 

 lower Columbia River sport and commercial 

 fisheries was 1.4 to 1. Passage of chinook smolts 

 through Snake and Columbia River dams certainly 

 had an influence on survival differences between 

 transported and nontransported groups. 



SUMMARY AND CONCLUSIONS 



This study was initiated to determine the 

 feasibility of creating or enhancing a fishery in a 

 specific area by releasing hatchery salmon smolts 

 into that area. The plan was to release hatchery 

 coho salmon smolts into an area and sample the 

 fisheries in the area to determine if the fish re- 



turned in great enough numbers to warrant ex- 

 pansion of this practice. 



Two groups of approximately 100,000 1968- 

 brood coho at Little White Salmon National Fish 

 Hatchery were marked— one with a right ventral 

 finclip and the other with a left ventral finclip. 

 Youngs Bay near Astoria, Oreg., was selected as 

 the release site for the LV-marked group. The 

 RV-marked coho were released at the hatchery. 

 The releases were made in April and May of 1970. 



The Youngs Bay and Columbia River gill-net 

 fisheries were sampled for these marks in the fall 

 of 1970 and 1971. A comparison of the catches and 

 hatchery returns of the two groups showed that 

 the two groups homed back to their respective 

 areas of release with very little straying. The con- 

 tribution of these two groups to the fisheries 

 sampled was 7.7 fish per 1,000 released for the 

 LV-marked Youngs Bay release and 11.7 fish per 

 1,000 released for the RV-marked Little White 

 Salmon Hatchery release. 



These statistics appear to favor the Little White 

 Salmon Hatchery release, but there are several 

 factors which prevent an accurate comparison of 

 the two groups. First, the LV-marked coho were 

 released in Youngs Bay 2 wk prior to and at a 

 smaller size than the RV-marked coho released at 

 the hatchery. Second, no evaluation was made of 

 the possible effects of delayed mortalities of the 

 LV coho due to hauling. Third, incomplete 

 sampling for these marks was carried out in the 

 ocean sport and commercial fisheries. Finally, 

 duplication of single fin marks in the ocean 

 fisheries prevented assignments to specific 

 experiments. These four factors could have a sig- 

 nificant influence on the contribution of either or 

 both groups of coho. 



Conclusions as to the practicality of transport- 

 ing fish to an area to create or enhance local 

 fisheries cannot be reached because of the four 

 unknown factors influencing contribution. 

 However, catches, hatchery returns, and the lack 

 of straying indicate that this practice is 

 biologically feasible. A study structured to 

 evaluate the total contribution of two releases 

 similar to those in this investigation and to 

 eliminate the unknowns is presently underway. 



ACKNOWLEDGMENTS 



We thank the personnel of the New England 

 Fish Company and Barbey Packing Corporation 



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