and recreation activities, all of which have contributed to habitat degradation or fish 

 population declines. Of 1 08 inventoried streams or river reaches, ninety-six have been 

 altered, degraded or otherwise identified as fisheries-impaired at some level (Pierce et al 

 2005). The majority of habitat degradation occurs on the valley floor and foothills of the 

 Blackfoot watershed and largely on private agricultural ranchlands. However, problems 

 also extend to commercial timber areas, mining districts, and state and federal public 

 lands. 



Distribution patterns of most salmonids generally conform to the physical geography 

 of the landscape, with species richness increasing longitudinally in the downstream 

 direction (Figure 5). Species assemblages and densities of fish can also vary greatly at 

 the lower elevations of the watershed. Native species of the Blackfoot Watershed are bull 

 trout {Salvelinus confluentus), westslope cutthroat trout {Oncorhynchus clarki lewisi), 

 mountain whitefish (Prosopium williamsoni), pigmy whitefish (Prosopium coulteri), 

 longnose sucker {Catostomus catostomus), largescale sucker (Catostomus macrocheilus), 

 northern pikeminnow {Ptychocheilns oregonensis), peamouth {Mylocheilus caurinus), 

 redside shiner (Richards onius balteatus), longnose dace {Rhinichthys cataractae) slimy 

 sculpin (Cottus cognatus) and mottled sculpin (Cottus bairdi). Non-native species of the 

 Blackfoot Watershed include rainbow trout {Oncorhynchus mykiss), kokanee {O. nerkd), 

 Yellowstone cutthroat trout (O. clarki bouvieri), brown trout {Salmo trutta), brook trout 

 {Salvelinus fontinalis), artic grayling (Thymallus arcticus), white sucker {Catostomus 

 commersoni), fathead minnow (Pimephales pomelas), northern pike {Esox lucius), brook 

 stickleback {Culaea inconstans), Pumpkinseed {Lepomis gibbosus), largemouth bass 

 {Micropterus salmoides) and yellow perch {Perca flavescens). 



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

 stem river system exhibit fluvial migratory life-history characteristics, whereas tributaries 

 support both migratory and resident populations. WSCT have a basin-wide distribution 

 and is the most abundant species in the upper reaches of the tributary system. Bull trout 

 distribution extends fi-om the main stem Blackfoot River to headwaters of larger 

 tributaries north of the Blackfoot River main stem. 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. However, 

 populations of rainbow trout are also established in back country mountain lakes, 

 primarily in the upper North Fork drainage. Brown trout inhabit -15% of the perennial 

 stream system with a distribution that extends fi-om 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 main stem Blackfoot River below the 

 Landers Fork. 



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