poor quality habitat. Also, Beaver Creek's elevation and severe winter conditions also contribute 

 to a short growing season and limited productivity. All the bull trout captured during the survey 

 were identified to be bull X brook hybrids. The bull trout hybrids are presumed to be part of a 

 non-resident fluvial population. Several age classes of sexually mature brook trout were captured 

 but at unexpectedly low densities. The low levels may be due to poor habitat conditions or low 

 stream productivity. The establishment of brook trout in Beaver Creek is limiting native trout; 

 by out competing westslope cutthroat and the genetic introgression with bull trout. 



Habitat Inventory 



Bear Creek: 



Habitat parameters in Bear Creek are in excellent condition. The channel is predominately stable 

 (>95%) with numerous undercut banks. The small numbers of unstable/eroding banks are within 

 the range for natural fluvial conditions. This high stability provides low sediment input and 

 clean spawning substrates for salmonids. Although fast water habitat types (riffles and runs) 

 dominate the channel, the pool to riffle ratios is sufficient to provide adequate fish habitat. Large 

 woody debris and meanders create most pool habitats with a few pools being created by boulders. 

 Continued recruitment sources are crucial for maintaining this channel diversity. 



Beaver Creek: 



Habitat parameters in upper Beaver Creek (above the irrigation diversion) are in good condition. 

 The channel is stable (100%) with numerous undercut banks. Although this high stability 

 provides low sediment input, fines and small gravels are still present in substrates. Sediment 

 sources might be originating off-site and contaminating the reach's salmonid spawning 

 substrates. Although fast water habitat types (riffles and runs) dominate the channel in this upper 

 area, the pool to riffle ratios is sufficient to provide adequate fish habitat. Large woody debris 

 and boulders create most pool habitats with a few pools being created by meanders. Continued 

 LWD recruitment sources are crucial for maintaining this channel's habitat complexity. 



Habitat parameters in lower Beaver Creek (below the irrigation diversion) are in poor condition. 

 The irrigation diversion has captured the stream's entire flow for numerous years. Immediately 

 below the diversion the stream channel no longer exists. Since the Beaver Creek channel does 

 not exist immediately below the diversion point, fish must migrate up the canal. The irrigation 

 channel may act as a partial fish barrier, excluding most fish. Ground water recharging 

 reactivates the stream channel approximately 0.5 miles down valley of the headgate and the lack 

 of discharge has altered the channel's dimensions, patterns and profile. These lower reaches are 

 unstable (<60% stability) with very few undercut banks (<18%). The channel's instability 

 increases sediment inputs resulting in high concentrations of substrate fines. These conditions 

 reduce salmonid spawning success. The pools in these reaches do not provide adequate fish 

 habitat. The channel has little LWD with most pool habitats being created by headcuts and 

 boulders. Reactivation of these reaches without extensive channel modifications would result in 

 an excessive and continuous sediment supply to Upper Willow Creek. The excessive sediment 

 would negatively impact Upper Willow Creek. 



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