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<br />abundance estimate in 2007. The 2007 abundance reflected fish removal that occurred <br />from 2004 through 2006. Fish removal done in 2007 will be evaluated with the 2008 <br />abundance estimate. Two other annual measures of removal effectiveness were <br />removal rate and recapture rate. Removal rate measured the proportion of fish <br />removed in relation to the abundance estimate. Recapture rate measured the percent <br />of tagged fish recaptured during removal. Comparison of the two rates provides insight <br />into how we gauge success. If we tagged a proportion of a population of fish in a <br />closed system with no loss of tags or change in the number of fish through immigration, <br />recruitment, emigration, or mortality and all fish behaved similarly to the sampling gear, <br />then we would expect recapture rate to equal removal rate. For example, if we tag and <br />release 100 fish from a population of 1000 fish (Le. 10% of the fish are tagged) and <br />later we remove 400 fish from the system, then our removal rate is 40% (400/1000 = <br />40%). If recapture rate equals removal rate then we would expect that 40 of those 400 <br />individuals would be recaptured tagged fish. If so, then recapture rate would equal 40% <br />(40/100 = 40%). <br /> <br />Movement of tagged fistr Recaptures of tagged smallmouth bass were examined to <br />determine the extent of movement within and between study sites. To determine if <br />smallmouth bass remained within each control and treatment reach, we examined the <br />proportion of smallmouth bass that moved out of each reach after they were tagged and <br />released on the first sampling occasion. High rates of movement between the two <br />reaches during the year would reduce our ability to compare control and treatment <br />reaches. We also examined movement of all smallmouth bass that we tagged in all <br />years, including fish initially tagged by us that were recaptured by another agency or <br />fish initially tagged by another agency that were recaptured by us. Distance moved was <br />the distance between the initial tagging location and the last capture location. We <br />excluded fish recaptured less than 7 days after initial tagging to reduce the immediate <br />effects of capture and examined movement of recaptured fish that were at large for two <br />time intervals: less than one year and greater than or equal one year. We also <br />excluded fish recaptured after escaping from Elkhead Reservoir in the above analysis, <br /> <br />8 <br />