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upstream of the Yampa River was restored. Low-flow conditions in drought years 2002 to <br />2004 increased water temperatures in the Green River to levels that likely mimicked pre- <br />dam conditions. This ensured a close match of Green and Yampa River water <br />temperatures during drought years when Colorado pikeminnow larvae were drifting <br />downstream from the Yampa River in summer. <br />? The Green River upstream of the Yampa River supported eight native fishes (nine if <br />bonytail is included) in 2002 to 2004, and only Colorado pikeminnow and bonytail did not <br />reproduce. Native fishes in Lodore Canyon declined in abundance in electrofishing, seine, <br />and drift net samples compared to those collected in 1994 to 1996. Ten native fishes were <br />collected in the Green River downstream of the Yampa River. Native fishes were <br />numerically dominant in electrofishing and trammel net samples; seine samples were <br />dominated by non-native taxa. <br />? Abundance of non-native fishes in Browns Park and Lodore Canyon increased in 2002 to <br />2004 compared to 1994 to 1996. Increases were throughout the study area and largest in <br />the upper portions of Lodore Canyon for small-bodied cyprinids, channel catfish, and <br />smallmouth bass. Smallmouth bass reproduction, which was not previously observed in <br />Lodore Canyon, was widespread and northern pike reproduction was also observed. <br />Salmonids were temporarily reduced in abundance in 2002, but increased in 2003 and <br />2004, and remained similar in abundance to that observed in 1994 to 1996. The overall <br />predator load in the Green River study area has increased. <br />? Diversity and abundance of other non-native fishes increased since 1994 to 1996. For <br />example, species not detected in 1994 to 1996 but found in 2002 to 2004 included creek <br />chub, brook stickleback, bluegill, and black crappie. Abundance of green sunfish and <br />black bullhead increased in 2002 to 2004 compared to the 1994 to 1996 sampling period <br />? A strong water temperature gradient played a role in controlling distribution and <br />abundance of fishes in Lodore Canyon. Further upstream expansion of several warm- <br />water fishes was restricted to upper Lodore Canyon because of relatively cool upstream <br />70