From the perspective of restoration, these cores also suggest spring creek restoration 

 methods should correct upstream sediment sources prior to channel construction or 

 placement of instream spawning gravels. 



In 2004, we also ran an upstream/downstream comparison at an undersized bridge 

 on Monture Creek (Dave Rosgen, personal communication). The upstream section is 

 geomorphically "unstable" compared to geomorphically stable reach below the bridge 

 (Dave Rosgen, personal communication). Although not statistically significant, the 

 samples recorded a higher percentage of fines (<6.35mm) in the unstable sample 

 compared to the lower sample. Based on prediction equations for percent survival at 

 emergence for bull trout (Fraley and Weaver 1991), core samplings upstream of Monture 

 Creek indicate lower survival (30%) compared to the downstream sample (38%). In this 

 area, a combination of an undersized bridge, historical timber harvest and large 

 concentrations of instream wood all appear to contribute to channel "instability." 

 Interestingly, the channel complexity brought on in part by charmel instability (log-jams 

 and beaver activity) also appears to provide a hi^ level of rearing area complexity 

 upstream of the bridge. 



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82 



