richness in unimpaired streams of western Montana is at least 14 (Bellman, 

 unpublished data). 



Number of long-lived taxa. Long-lived or semivoltine taxa require more than a 

 year to completely develop, and their numbers decline when habitat and/or water 

 quality conditions are unstable. They may completely disappear if channels are 

 dewatered or if there are periodic water temperature elevations or other 

 interruptions to their Life cycles. Western Montana streams with stable habitat 

 conditions are expected to support six or more long-lived taxa (Bollman, 

 unpublished data). 



i 



RESULTS 



Habitat assessment 



Figure 1 compares habitat assessment results for the two sites studied. Breakdown 

 of total scores into the nine evaluated components is presented in Table 1. 



Figure L Total habitat assessment scores, expressed as percent of maximum, for two sites on Siiields 

 River, August, 2000. 



McCloud station 



Johnstone station 



Habitat assessments indicate that conditions contrasted sharply between McCloud 

 station and Johnstone station. Overall assessment at McCloud station suggested sub- 

 optimal conditions, whereas Johnstone station was judged to have marginal habitat. At 

 McCloud station, all but one of the instream indicators were scored optimally; the 

 exception was sediment deposition, since some point bar formation was noted. In 

 addition, flow status was judged sub-optimal, as were all of the streambank and riparian 

 indicators. 



In contrast, degradation of instream habitats was indicated by the assessment 

 conducted at Johnstone station. Substrate embeddedness was noted, and sediment 

 deposition was judged to be heavy. The investigator detected marginal flow status at this 

 location. Streambank stability and vegetation were given poor scores, and the riparian 

 zone was noted to be minimally intact. 



4 



