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captured averaged 644 mm TL (191 to 825 mm TL, Bestgen et al. 2006), and all were healthy and fat. Most were captured from deep eddies and pools or runs. There was evidence of reproduction by northern pike in Lodore Canyon as a 191 mm TL fish, presumably age-0, was captured in summer 2003 in lower Lodore Canyon. Channel catfish in the study area are restricted to the Green River downstream of Browns Park. Distribution and abundance of channel catfish in Lodore Canyon in 1994 to 1996 was relatively restricted, with few fish occurring in upstream reaches and abundance overall was low (Fig. 15). In the 2002 to 2004 period, abundance increases were evident across Lodore Canyon, particularly in downstream reaches, and channel catfish was most abundant in Whirlpool Canyon. Channel catfish abundance was increased only slightly in some reaches in 2005 over 2002-2004 levels, but in 2006, was markedly higher, particularly in Whirlpool Canyon. There continues to be no direct evidence of reproduction by channel catfish in the Lodore Canyon reach of the Green River because we did not collect any channel catfish < 180 mm TL in seine or drift net samples in the Green River; channel catfish are a regular component of drift samples collected annually in the lower Yampa River. Size structure of channel catfish in electrofishing samples in Lodore Canyon changed between the 1994-1996 and 2002-2004, mainly because of increased abundance in 2002 to 2004 (Fig. 33, in Bestgen et al. 2006). In general, during both periods larger fish (> 300 mm TL) were more common in the upper reaches of Lodore Canyon and smaller fish were more common in lower Lodore Canyon; the pattern is more obvious in 2002 to 2004. Similar to lower Lodore Canyon, channel catfish in Whirlpool Canyon in the 251 to 300 mm TL size class dominated populations, although a few very large fish were also present. No small channel catfish were sampled in Lodore Canyon, perhaps indicating absence of reproduction by that species there. Small channel catfish were present in downstream Whirlpool Canyon. Smallmouth bass are presently distributed from upstream Browns Park, being discovered there as recently as summer 2006 upstream as far as RK 604, downstream throughout Lodore and Whirlpool canyons and Island-Rainbow Park. They were first discovered in Browns Park during the additional sampling conducted in August 2006 that was aimed at obtaining a better 26