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<br />among sample occasions, greater total effort for fish removal in any year was primarily <br />due to more sample occasions. However, in 2006 and 2007 removal effort also <br />increased due to the expansion of the treatment reach to 24 miles. <br /> <br />Effort expended to remove smallmouth bass from the Little Yampa Canyon treatment <br />reach using boat electrofishing increased over time from 15 hours in 2003 to 156 hours <br />in 2007 (Table 1), In 2003 at Little Yampa Canyon, we sampled the control and <br />treatment reaches equally and removed small mouth bass on two occasions. In 2004 <br />and 2005, we sampled the treatment reach twice as often as the control reach and <br />removed smallmouth bass on eight occasions each year. We completed five removal <br />occasions in 2006, a low water- year and seven occasions in 2007, a normal water- <br />year. In those two years, extra effort was required to remove bass from a larger <br />treatment area. Effort expended to remove small mouth bass from Little Yampa Canyon <br />with electric seine ranged from 21 to 42 hours (Table 2). <br /> <br />Effort expended to remove smallmouth bass from Lily Park was relatively consistent <br />among years with four to five sample occasions each year and 24 to 30 hours of boat <br />electrofishing each year (Table 1). Length of the reach remained constant at 5 miles in <br />all years. Smallmouth bass were removed from Lily Park with 2 hours of electric seine <br />in 2007 (Table 3). <br /> <br />Fish captured with boat electrofishing- Using boat electrofishing we removed 15,190 <br />smallmouth bass with a biomass of 2,441 kg and tagged and released 4,876 <br />smallmouth bass (1,801 kg) in 5 years at our two study sites (Table 5). We captured <br />and released another 88 smallmouth bass (51 kg) in areas outside of our study sites. <br /> <br />At Little Yampa Canyon, 8,883 smallmouth bass (1,923 kg) were removed from the <br />river with boat electrofishing; 5,677 (1,878 kg) of those fish were adults (Table 5). <br />Generally, we removed increasing numbers of both adult and sub-adult smallmouth <br />bass each year from Little Yampa Canyon, with the most bass (n = 2,785) removed in <br /> <br />12 <br />