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and we suggest continuing efforts started by Martinez (2007) to standardize electrofishing gear by providing field crews with technical assistance in testing and maintaining electrofishing equipment to insure that it operates at maximum potential. Although we observed declines in abundance that we attributed to our annual removals, compensatory mechanisms (e.g., recruitment and immigration) likely off-set some of our removal effort. This is to be expected in any fish removal program based on stock-recruitment dynamics and the meta-population structure we observed in this particular system. For example, throughout our study period, recruitment appeared robust based on abundant young-of-year smallmouth bass captured with electric seine and the wide distribution and high abundance of yearlings captured by boat electrofishing. Immigration of smallmouth bass into our study sites was documented based on the movement of fish between our two study sites, invasion of escapees from Elkhead Reservoir, and movement of tagged fish from other reaches such as South Beach, Maybell, and Yampa Canyon. The potential for smallmouth bass movement among reaches was shown by movements of up to 50 miles in less than a year and up to 100 miles after periods of more than a year. Documenting the rate of immigration into our study sites and improving our knowledge of movement dynamics in the Yampa River will require increased tagging effort in the Craig, South Beach, and Maybell reaches. Long-range movements of smallmouth bass throughout the Yampa River suggest that expanded and higher removal rates are needed river wide if we are to sustain removals in our study reaches. We documented that recapture rate (the proportion of tagged fish recaptured at least once) was lower than removal rate in almost all years. A large portion of tagged smallmouth bass (58% at Little Yampa Canyon and 70% at Lily Park) were never seen again after their release, suggesting that the proportion of tagged fish in the population was reduced by some combination of emigration, tagging mortality, or tag loss. And that these rates were higher at the shorter (5 mile) Lily Park reach than at Little Yampa Canyon which was 24 miles long. Smallmouth bass moved equally in upstream and 23