Survival Of Hatchery Subyearling Fall Chinook Salmon in the Free-Flowing Snake River and Lower Snake River Reservoirs, 1998-2001.

Technical Information Center Oak Ridge Tennessee

关键词: Fisheries;    Fishery surveys;    Snake river;    Dams;    Environmental impacts;   

RP-ID  :  DE2003807644

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

We report results from four years (1998-2001) of an ongoing study of survival and travel time of subyearling fall chinook salmon in the Snake River. We report analyses of associations among river conditions and survival and travel time estimates, which include data from 1995 through 1997. At weekly intervals from early June to early July each year (mid-May to late June in 2001), hatchery-reared subyearling fall chinook salmon were PIT tagged at Lyons Ferry Hatchery, trucked upstream, acclimated, and released above Lower Granite Dam at Pittsburgh Landing and Billy Creek on the Snake River and at Big Canyon Creek on the Clearwater River. We compared a number of characteristics of hatchery and wild fish. Hatchery and wild fish were similar in 2001, and from 1995 through 1997. Results for 1998 through 2000 showed some relatively large differences between hatchery and wild fish. However, recent information suggests that a considerable proportion of wild subyearling chinook salmon migrating in a given year may actually be stream-type (spring/summer), rather than ocean-type (fall) fish, which may account for some of the differences we have observed.