Genetic Evaluation 



Electrophoretic analysis of samples of Salmo collected in the vicinit:/ of 

 sediment monitoring stations on Gold Creek, Martin Creek, Meadow Creek, Moose Creek, 

 Sleeping Child Creek, and Tolan Creek detected only westslope cutthroat Salmo clarki 

 levisi genetic material (Appendix A-1). This result indicates we are dealing with 

 pure v7estslope cutthroat populations in these drainages. Only three other streams 

 with pure populations have been identified in the Clark Fork River basin compared 

 to numerous introgressed populations. The Bitterroot drainage is suspected to 

 harbor a fair number of the pure populations still available in Western Montana. 



Fish Populations Rock Creek Drainage 



West Fork of Rock Creek 



The West Fork of Rock Creek was sampled at tz-io locations; one 2.23 miles 

 from the mouth, the other 13 miles upstream from the mouth below Sand Basin 

 Creek. The species of fish found included cutthroat trout (suspected pure 

 because near absences of rainbow trout) , rainbow, bull trout (suspected pure 

 since no brook trout found in all West Fork drainage stream), mountain whitefish, 

 longnose sucker, longnose dace, and sculpins (Table 1). Cutthroat dominated the 

 catch with mountain whitefish and bull trout sharing the second most abundance. 



Ross Fork of Fv.ock Creek 



The Ross Fork of Rock Creek was sampled upstream from the sediment monitoring 

 station because of the interference with a headgate structure, bottom disturbance 

 and potential flow problems from the diversion. The species of fish found 

 included: cutthroat, brook, and bull trout, mountain whitefish, and sculpins 

 (Table 2). Cutthroat were dominate in terms of number of individuals found and 

 are suspected to be pure since no rainbows were collected. 



Sand Basin Creek 



Sand Basin Creek was sampled at two locations; one approximately 0.3 miles 

 from the mouth, the other 3.2 miles from the mouth. The species of fish found 

 differed between the two sections. The upper section had only cutthroat trout 

 and sculpins whereas the lower section was cutthroat, bull trout, mountain 

 whitefish, and sculpin (Table 3). The upper section of Sand Basin Creek had 

 100% sand substrate, the worst sediment situation of all sections sampled. 



Fish Populations in Bitterroot Drainage 



Daly Creek 



We sampled Daly Creek approximately 0.65 miles upstream from the confluence 

 with Skalkaho Creek. We now have two estimates on this section since estimates 

 were completed in 1984 as well as in 1985 (Table 4 and 5). The Daly Creek section 

 was lengthened by 150 feet which improved the estimates considerably. Confidence 



