sustaining "wild trout" populations. Distribution patterns of most salmonids generally 

 conform to the physical geography of the landscape, with species diversity increasing 

 longitudinally in the downstream direction (Figure 3). Species assemblages and densities 

 offish can also vary greatly at the lower elevations of the watershed. 



Most salmonids (WSCT, bull trout, rainbow trout and brown trout) in the river 

 system exhibit migratory behavior and rely on tributaries at multiple life stages. WSCT 

 has a basin- wide distribution and is the most abundant species in the upper reaches of the 

 tributary system. Outside of the Clearwater drainage, WSCT exhibit both resident and 

 migratory (fluvial) life-history behavior. Resident populations of WSCT inhabit 

 tributaries where they complete their entire life cycle. By contrast, fluvial WSCT spawn 

 and rear in small tributaries and exhibit migratory behavior, which includes use of the 

 larger streams and rivers. Bull trout distribution extends from the mainstem Blackfoot 

 River to headwaters of larger tributaries north of the Blackfoot River mainstem; however, 

 juvenile bull trout will rear in smaller "non-spawning" tributaries, some of which are 

 located in the Garnet Mountains. Rainbow trout distribution is limited to the Blackfoot 

 River downstream of Nevada Creek and lower reaches of the lower river tributaries, with 

 the exception of Nevada Creek upstream and downstream of Nevada Reservoir. 

 Rainbow trout occupy -10% of the perennial streams in the Blackfoot watershed, with 

 river populations reproducing primarily in the lower portions of larger south-flowing 

 tributaries. Brown trout inhabit -15% of the perennial stream system with a distribution 

 that extends from the Landers Fork down the length of the Blackfoot River and into the 

 lower foothills of the tributary system. Brook trout are widely distributed in tributaries 

 but rare in the mainstem Blackfoot River below the Landers Fork. 



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