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1,592, mean TL = 210 mm) in autumn 2003. Our autumn 2003 trammel net sampling occurred six to nine d after stocking at Echo Park, but we did not detect any of those individuals. We documented that hatchery-reared bonytail survived for short periods in the wild, but they do not appear to survive over winter because we captured no fish that were at large more than a few weeks. We did capture early June-stocked bonytail downstream of Echo Park in late September 2005 (unpublished data). Lack of longer-term recaptures was in spite of stocking in all three of our sampling years, 2002 to 2004, in areas upstream of our sampling. We feel confident to detect their presence because we used an array of gears in a wide variety of habitat types in all seasons except winter. Even though bonytail captured in autumn 2004 were healthy shortly after stocking, observations of fish captured in autumn 2005 that were stocked the previous June revealed that most fish were in poor condition. Most fish had multiple Lernea infections, some had fungus, and their general appearance and color were poor. In summer 2005, we also netted a weakly swimming bonytail in Split Mountain Canyon with an aquarium net. The specimen had a fungus infection, Lernea scars, missing scales, and was near death. Means to increase survival of stocked bonytail in this portion of the Green River should be investigated. Razorback sucker.-We did not capture any pure adult razorback suckers in the study area in the three years of sampling from 2002 to 2004; one was detected in Lodore Canyon in the 1994 to 1996 period. We captured two razorback sucker X flannelmouth sucker hybrids, identified on the basis of characteristics that were intermediate between the presumptive parental species. Both individuals were from lower Whirlpool Canyon and one recaptured individual was in the Recovery Program database as a pure razorback sucker even though it was clearly a hybrid and exhibited nearly no nuchal hump. We already discussed the two putative razorback sucker X white sucker hybrids, one in each of years 2003 and 2004, captured in drift nets set in the Green River upstream of the Yampa River. Non-native predators.-Eighteen northern pike were captured by electrofishing, two by seining, and one in a trammel net and all were found in the lowermost 16 km of Lodore Canyon and Whirlpool Canyon. Three were taken in 2002, 10 in 2003, and eight in 2004. Five pike were captured in Lodore Canyon reach LD3, 11 in LD4, three in WH1 and two WH2. Most LD4 fish 57