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channel catfish numbers collected in fyke nets from the Green River by Crowl and Badame (2000) were juveniles. Channel catfish reproduce in the Yampa River (Nesler 1987; Colorado State University Larval Fish Laboratory, unpublished data) but few small juvenile channel catfish have been found in the lower Yampa River (Miller et al. 1982). Our study did not collect small juvenile channel catfish in any of the various gear types we used. Channel catfish generally mature between approximately 250 mm and 400 mm (Carlander 1969), indicating that the majority of fish from the Yampa River were subadult and small adult fish. The lack of smaller fish indicates that few catfish are reared in the lower Yampa River in Dinosaur National Monument and that migration of smaller individuals from the Green River may be the primary source of recruitment. Condition of channel catfish in 1998 was low with relative weights averaging less than 90 in most study reaches. In 1999, relative weights of fish captured by angling were much higher than observed the previous year, i.e., 120 and 123 respectively for treatment (removal) and control reaches. However, the relative weight offish collected from electrofishing (with the exception of reach 4) were more similar to those in 1998. Differences in relative weight offish captured by angling may have been the result of increased condition due to reduced density or an artifact of sampling. During 1999, a larger number of anglers participated in removal efforts. Fish subsampled for individual weight measurement may have been kept longer under stressful conditions in buckets resulting in increased water retention. Because few differences were observed in relative weight between angling in 1998 and electrofishing in 1999, it would seem more likely that the differences in condition of fish captured by angling in 1998 and 1999 were probably due to a sampling artifact. A distinct gradient of channel catfish size exists between the Yampa River above Cross 14