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Most habitat in the treatment reach suitable to support small-bodied smallmouth bass was sampled on three sampling passes conducted from late-July/early August to early September, each pass taking about 9 days to complete. That period was targeted for removal because young smallmouth bass that had hatched in late June through July were of a size sufficient for efficient capture using the electric seine. Main areas sampled were shallow, had low-velocity, and were typically shorelines of pools and runs with cobble or large substrate. A sampling pass was also completed during this time frame in the control area so that small-bodied smallmouth bass abundance could be compared to that in the treatment area. Native fish evaluation sampling.-- Sampling for this study typically began by early to mid-September and extended into late-October until the river froze. In each year, three to four sampling trips of 7 to 9 nine days each were conducted, and similar per trip sampling effort was usually expended in the control and treatment reaches. Sampling in both reaches during each pass would reduce confounding of comparisons of fish abundance through time if river-wide changes in water temperature, flows, turbidity or other factors were responsible for changes which may otherwise be attributable to a reach (removal) effect. We attempted to sample a mix of channel areas across the reaches, including backwaters, eddies, pools, riffles, runs, pools isolated from the main channel, and low velocity shorelines of pools and runs. The number of channel area types sampled was about proportional to their availability, except that most isolated pools were sampled because they were an unusual and biologically interesting habitat type. We attempted to sample a similar number of habitat areas in each of the control and treatment reaches, although differences in the mix of habitat types in each reach did not always allow for that. Some sites were accessible by vehicle but most were sampled from canoes during this low-flow autumn period. Low flows also limited access by rafts or other craft capable of transporting heavier boat-based electrofishers that may be more efficient at sampling the longer and deeper pools in some reaches. Anderson (2005) was able to sample a couple pools in the Duffy Tunnel area with a raft electrofisher. When we tried this gear type, we could not navigate longer river reaches, and found that water depth and limited mobility 4