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W Comparisons of our data to historical captures suggested that Colorado pikeminnow were more abundant in Lodore Canyon in 1994-1996 than at any time since 1980 (Holden and Crist 1981). Using slightly different electrofishing gear and sampling fixed sites, Holden and Crist (1981) captured two Colorado pikeminnow for a capture rate of 0.08 fish/h of electrofishing. In 1987-1988, Karp and Tyus (1990) sampled Lodore Canyon with an electrofishing raft and captured three Colorado pikeminnow (mean = 0.27 fish/h). Capture rates for Colorado pikeminnow were relatively high in 1994 to 1996 at 0.6 fish/h (we modified our estimates of pikeminnow abundance reported in Bestgen and Crist 2000 using the same methods used in this study) but apparently declined in 2002 to 2004 to about 0.4 fish/h. Higher recapture rates in the 2002 to 2004 period was likely the result of intensive basin- wide sampling for Colorado pikeminnow in 2000 to 2003 and capture and tagging of a relatively large number of pikeminnow in Lodore Canyon in a separate study (Kitcheyan and Montagne 2006). Lodore Canyon remains an important seasonal-use area for Colorado pikeminnow. Kitcheyan and Montagne (2006) found that Colorado pikeminnow used Lodore Canyon seasonally, mostly in summer and autumn, and particularly in low-flow years. Presence of a ripe and tuberculate male Colorado pikeminnow in Lodore Canyon in summer in each of 2001 and 2003 indicates possible spawning in Lodore Canyon. Roundtail chub.-Chubs were absent in Browns Park, rare in Lodore Canyon, more common in Whirlpool Canyon, and less so in IRP in 2002 to 2004 (Fig. 16). Electrofishing captured only nine adult roundtail chub in three years of sampling from 2002 to 2004 in Lodore Canyon in reaches LD1, LD3, and LD4; seining captured only seven small individuals (12 to 125 mm TL) and they were from the same reaches. In comparison, 46 roundtail chub adults were captured with electrofishing in the Whirlpool Canyon reach and 272 small chubs (13 to 117 mm TL) were captured by seining. A total of 72 small chubs (18 to 86 mm TL) were captured in the Island-Rainbow Park reach with seining from 2002 to 2004. All small chubs captured in 2002 to 2004 were identified as roundtail chub, based on morphological and meristic characters, although the longer fin lengths were often more typical of humpback chub (Muth 1990). 51