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and CPUE for Colorado pikeminnow in electrofishing samples declined in 2002 to 2004 <br />compared with 1994 to 1996, particularly in reaches LD3 and 4 (Fig. 14); CPUE data were not <br />significantly different. In the recent period, Colorado pikeminnow relative abundance was <br />highest in lower Whirlpool Canyon, but was similar to or less than Colorado pikeminnow <br />abundance in the lower reaches of Lodore Canyon where it was most common in 1994 to 1996 <br />Colorado pikeminnow in Lodore Canyon in each study period were a mix of sizes <br />including a single fish in each period in the 351 to 400-mm TL size class (Fig. 15). Modal size <br />in the 1994 to 1996 period was larger than in the 2002 to 2004 period. Modal size of <br />pikeminnow in Whirlpool Canyon was similar to that in Lodore Canyon in the 2002 to 2004 <br />period. <br />Roundtail chub was found in every reach of the study area in 2002 to 2004 except <br />Browns Park and showed increased downstream abundance in both seine and electrofishing <br />samples in a downstream direction. However, roundtail chub abundance in electrofishing <br />samples declined in 2002 to 2004 compared to the 1994 to 1996 period (Fig. 16); catch rate was <br />reduced by more than 50%, a significant decline (Table 8). Roundtail chub abundance was <br />higher in upper Whirlpool Canyon compared to other reaches but overall, represented a <br />relatively small portion of the fish community there. Roundtail chub abundance in seine samples <br />was low in all Lodore Canyon reaches in 2002 to 2004 and declined relative to samples collected <br />in 1994 to 1996. Similar to adult chub captured by electrofishing, small roundtail chub captured <br />in seine samples were most abundant in upper Whirlpool Canyon and were present in lower <br />Whirlpool Canyon and Island-Rainbow Park, but overall represented a relatively small <br />proportion of samples. <br />In general, only large roundtail chub (usually > 300 mm TL) were present in Lodore <br />Canyon. A mix of sizes was present in Whirlpool Canyon samples (Fig. 17) and included nearly <br />all adult roundtail chubs < 300 mm TL captured in this study. <br />Speckled dace was distributed throughout the study area but was generally uncommon in <br />the 2002 to 2004 period in most reaches (Fig. 18). Speckled dace abundance in electrofishing <br />samples declined from the 1994 to 1996 period to the 2002 to 2004 period; CPUE data showed a <br />28