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Temperature 



Temperature was recorded at random times of day while electroshocking. As a result, 

 comparisons of species specific stream temperatures using statistical analysis were not 

 appropriate. However, temperature trends were distinguishable for each species except at 

 sites where species were rare in occurrence (Figure 7). 



Torrent sculpins tended to be found at sites with warmer stream temperatures than the 

 other sculpin species. The observed mean temperature at sites where torrent sculpins were 

 abundant was 52.4°F. This was 4.5° higher than the observed mean temperature at sites 

 containing slimy sculpins. The observed mean temperature where slimy sculpins were 

 abundant was 47.9°F. Shorthead sculpins appeared to prefer sites with cooler stream 

 temperatures. The observed mean water temperature for shorthead sculpins was 44.0°F, 

 3.9° lower than that for slimy sculpins and 8.4° lower than the observed mean temperature 

 for torrent sculpins. 



The warmest temperatures recorded at a site with sculpins present was 62.5°F.. All 

 three sculpin species were found at sites with this stream temperature. However, all three 

 species were either uncommon or rare in abundance at these sites. 



Gradient 



Stream gradients appeared to be an important factor influencing sculpin distribution 

 within the study area. Sculpins were found at sites with stream gradients from less than 1 

 percent to 2 percent (Figure 8). In general, each sculpin species was more likely to be 

 found at sites with approximately a 1% stream gradient. Sculpins were not found at sites 

 with gradients exceeding 2 percent. 



Slimy sculpins were able to tolerate the widest range of stream gradients. Fifty-five 

 percent of the sites containing slimy sculpins had a 1% stream gradient. Approximately 



