Discussion 



Based on the results of sampling and field identification methods 

 employed, two sculpin species are present in the study area. The 

 distribution of each species varies greatly. Slimy sculpin were 

 the most widespread longitudinally in the study area (similar to 

 1991 findings) . However, this species was mainly present south 

 of Libby. North of Libby it was found only in Pipe Creek. In 

 the Kootenai drainage, in close proximity to the main river, 

 slimy sculpin appear to be displaced longitudinally by torrent 

 sculpin. 



Torrent sculpin were found to have a more restricted longitudinal 

 range within the study area. They were typically found in 

 tributary streams of the Kootenai River drainage, in close 

 proximity to the main river. Two exceptions to this were the 

 Fisher River watershed and as Gangemi (1992) found, on Tobacco 

 River tributaries. Here, torrent sculpin were found far from the 

 main river. Sites in the Tobacco watershed with typical low- 

 order stream characteristics did not contain sculpin. Those 

 sites in the Tobacco occupied by torrent sculpin had stream flows 

 affected by most land use disturbances. 



Sculpin species in this survey were essentially allopatrically 

 dispersed, with sympatry restricted to a few larger-order 

 watersheds. Habitat of various tributaries in close proximity to 

 major waterways appear to be suitable for slimy sculpin, but 

 slimy sculpin were typically displaced upstream of the torrents 

 on tributaries where both species occurred. This was also noted 

 in the 1991 study (Gangemi 1992) . 



Factors Influencing Sculpin Distribution 



Stream Character 



These two sculpin species appear to prefer riffles, and to a 

 lesser degree, the transition area between runs and riffles. 

 Generally, stream segments were not randomly sampled, for habitat 

 preferences. Therefore, concluding that the sculpin species 

 prefer riffle habitat could be a reflection of sampling 

 methodology bias rather than a valid conclusion. 



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