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Reasons for the aecnne or the Pacific anaaromcus saimcnias vary oy soecies ana 

 geograonic area. The aeoressea status of the 214 siocks reriects the interaction of 

 nnerently variable environmental conamons. sucn as oceanic oroauctivity ana weather 

 oatterns. ana a variety cf management activities. In general, stock survival is threatenea 

 cy some comDination of hyaroeiectric aeveiooment ana ODeration. fisn harvest, fish 

 natcnery influences on aisease ana genetic fitness, ana fish haDitat ccnaitions. These 

 management activities sometimes are referrea to as the "four H's." 



3 Hydroelectric, fiooa control, ana irrigation aams have reaucea fish production in 

 many arainages througnout the range of the Pacific saimon. steelheaa. ana sea-run 

 cutthroat trout. This is especially true in the San Joaauin ana Sacrament River 

 Valleys of central California, and the Cclumoia River Basin of Idaho. Oregon ana 

 Washington. Recovery of as many as 20% to 40% of the stocks icentifiea by 

 AFS as "at risk" is limitea primarily by aam operations. The orppiem of hyaroeiectric 

 aevelopment ana coerations is particularly acute in the ColumDia River Basin, 

 wnere: (a) more than 30% of the saimon. steelheaa ana sea-run cutthroat trout's 

 historic range has been biockea by aams without fish passage facilities, (b) adult 

 fish have aifficulty in locating ana negotiating past aams wnere laaders have 

 been installed, (c) airect mortality of juvenile fisn as a result of passing througn 

 ppwer turpines is estimatea at 12-20% per dam. and (d) mortality of juvenile fish 

 has mcreasea aue to an approximately four-fold increase in aownstream travel 

 time (from 7-9 days to nearly 4 weeks) as a result of turning all but aoout 50 

 miles of the Columbia River into a series of placid lakes. The aemise of a large 

 majority of the extinct stocks is attnbutaole to dam construction and operation. 



o Harvest of Pacific salmon, steelheaa, ana sea-run cutthroat trout occurs in a 

 variety of sport, commercial, ana subsistence fisheries. Because small naturally 

 spawning fish stocks mix in the ocean with abundant hatchery stocks, management 

 for a "maximum sustained yield" can result in overharvest of some stocks, 

 appropriate harvest of some, and unaernarvest of others. Further conrounaing 

 the issue is the fact that much of the commercial harvest occurs outside the 

 national waters of the U.S. and of Canada, ana much of the suPsistence narvest 

 is guaranteea unaer treaty or given special priority by law. As a result, complex 

 junsaictional authorities must grapple with allocating a "fair share" of an ever- 

 dwinaling resource amoung various nations, states, and tribes. 



o Hatcheries were built to be a part of the solution to declining populations of 

 salmontds. However, many have become part of the problem and some have 

 had a subtle, but adverse impact. Traditional hatchery practices have contributed 

 to the decline, or may limit recovery, of 1 04 of the 21 4 stocks identified by AFS 

 as "at risk." Hybridization of hatchery stock with wild salmonids can reduce the 

 genetic fitness of the wild stock by affecting run timing and life history characteristics 

 impprtant to long-term viability. Competition between juvenile wild salmon, 

 steelhead. and sea-run cutthroat trout and juvenile hatchery fish (that typically 

 are larger because of hatchery feeding and/or time of hctching, and are released 

 in large numbers) can be overwhelming. Further, crowded rearing conditions, 

 warmer water, and greater concentrations of fish waste in many hatcheries can 

 increase the incidence of disease among hatchery fish that can be transmitted to 

 naturally-reproducing fish. Genetic contamination of the remaining lower Columc.a 

 River coho population by hatchery fish, and the resulting extinction of "wild" genes. 



PACFISH Strategy Executive Summary: Page - 2 



