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<br />much of the river was shallow enough for most fish to be susceptible to capture and flows <br /> <br />permitted use of electrofishing throughout the year (Dale Ryden, USFWS, personal <br /> <br />communication). Although we captured catfish with electrofishing gear on the Yampa River, more <br /> <br />fish were removed per trip by angling. Santucci et al. (1999) observed that angling was the most <br /> <br />efficient means of removing channel catfish from impoundments and Stauffer and Koenen (1999) <br /> <br />reported that both angling and low-frequency electrofishing were the most effective methods of <br /> <br />capturing flathead catfish Pylodictis olivaris in the Minnesota River. Both electro fishing and <br /> <br />angling represent effective removal methods. Electrofishing is more effective in shallow, higher <br /> <br />velocity habitats, while angling is more effective in deeper habitats. Angling offers the added <br /> <br />capability of being able to spend more effort in areas where success is greater. More catfish were <br /> <br />captured by angling in the Yampa River because deeper pools were sampled more effectively, <br /> <br />greater intensity could be exerted within a given reach, and anglers traveling in canoes could <br /> <br />traverse the river for a longer time period (i.e., rafts could not be used after flows receded below <br /> <br />28 m3s, whereas canoes could float through the canyon in flows down to 5.1 m3s) than <br /> <br />electro fishing gear. Because both methods are complimentary and similar costs, both methods <br /> <br />should be included in future removal efforts. <br /> <br />Telemetry observations of channel catfish showed little movement in either the San Juan <br /> <br />and Yampa rivers during the baseflow period with most fish moving less than 8 km (Brooks et al. <br /> <br />1999 Modde et al. 1999), which aided in the assessment of removal efforts. In addition, sedentary <br /> <br />behavior of catfish allows more efficient removal effort since collection effort can be concentrated, <br /> <br />thereby saturating specific reaches. A significant negative slope in catch per unit effort of catfish <br /> <br />angling in the Yampa River in three of four reaches suggested that channel catfish numbers <br /> <br />12 <br />