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FEEDBACK: Salmon Extinctions by Fred Mensik Columbia Basin Bulletin, February 8, 2008

In the Feb. 2, 2008 issue of the CBB, a sentence in the article entitled "Research Estimates Salmon Extinctions for Historical Baseline" reads, "In total it is estimated that 40 percent of the West's salmon and steelhead habitat is no longer accessible to the fish".

While the percentage may be correct, the reader should recognize that the remaining 60 percent never supported and will never support the volume of fish production that the inaccessible 40 percent once maintained in the Snake River basin. For example, the North Fork of the Clearwater River represented only 26 percent of the entire Clearwater River subbasin habitat for anadromous fish (NPT and IDFG 1990), but 50 to 60 percent of the Steelhead entering the Clearwater River spawned in the North Fork of the Clearwater River and its tributaries (NPPC Clearwater Subbasin Assessment). Additionally, "Chinook salmon smolt production from the Clearwater subbasin was estimated by Chapman (1981) to be 1,817,625. Chapman's data suggests that tributary systems in the Lower Clearwater and Upper and Lower North Fork AUs were historically substantial producers of chinook salmon, accounting for roughly 65 percent of the chinook salmon smolt production for the Clearwater subbasin tributaries (excluding mainstem production)" (NPPC Clearwater Subbasin Assessment). Dworshak Dam on the North Fork of the Clearwater River, a few miles upstream from the main stem Clearwater River, eliminated only 26 percent of the Clearwater River basin habitat, but it ended a major portion of the Steelhead and Chinook production of the entire Clearwater River basin.

The most abundant specie to return to the Snake River system was Sockeye, with the largest population of Sockeye returning to the Payette River system. The Payette River system has been part of that 40 percent lost habitat for decades. Additionally, 100 percent of the prime fall Chinook habitat, which existed in an area above Brownlee Dam on the Snake River, in Idaho, is also part of the 40 percent lost habitat.

In 2007, up to 86 percent of the fish collected at Lower Granite Dam were of hatchery origin (Lower Granite Dam Smolt Monitoring 2007 Annual Report). It is the fish production areas in the inaccessible 40 percent of the Snake River basin that historically produced the most number of fish. Essential habitat was lost due to dams like Dworshak, Brownlee, Hells Canyon, Oxbow, C.J. Strike, Bliss, American Falls, Lower Salmon Falls, Upper Salmon Falls A, Upper Salmon Falls B, Swan Falls, Milner, Twin Falls, Barber, Black Canyon and Upper Malad dams, all built without functioning fish ladders or fish bypass systems and all in the state of Idaho. If objectives to be attained include preventing the extinction of evolutionarily significant units and/or having healthy, harvestable, self-sustaining populations of wild anadromous fish, then fish access to an adequate volume of productive spawning habitat is essential.

Related Pages:
Research Estimates Salmon Extinctions for Historical Baseline, Columbia Basin Bulletin, 2/1/8
FEEDBACK: Salmon Extinctions by Jim Esch, Columbia Basin Bulletin, 2/8/8