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initiated because riverine backwaters are the habitats where piscivorous centrarchids are <br />most likely to come into direct contact with early life stages of the endangered fish. <br />Goal <br />The ultimate goal of non-native fish removal is to increase survival rate of larval <br />and juvenile endangered fish. The primary objective of this project was to remove from <br />backwaters all centrarchids and other large, nonnative fish species deemed detrimental to <br />the native fish community, i.e., black bullhead Ictaluras melas, common carp Cyprinus <br />carpio, white sucker Catostomus commersoni, channel catfish. A secondary objective <br />was to evaluate efficacy (both practicality and degree of measurable success) of using <br />mechanical removal of predators as an ongoing recovery program activity. <br />TARGET AREA <br />Non-native fish were removed from backwaters of the Colorado River from a 93- <br />km reach (Fig. 1) extending from the Grand Valley Irrigation Company Diversion Dam <br />at Palisade, Colorado (rm 185.1; rk 298) downstream to the Westwater Ranger Station, <br />Utah (rm 127.6; rk 205). <br />METHODS <br />Electrofishing was selected as the means to capture centrarchids because seines <br />have been found to be ineffective where vegetation or other structure interferes with <br />netting (Bundy and Bestgen 2001). Backwaters were electrofished twice annually from <br />1999 through 2001: once prior to spring runoff (March-April) and once following runoff <br />4