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<br />r <br />;' <br />, <br />:1 <br /> <br />in the river mainstem. Varying dam operations had no effect <br />on water temperatures downstream. <br /> <br />i' <br /> <br />* Adult Humpback chub distribution apparently compressed <br />around the warm Little Colorado River where they continue to <br />successfully spawn. <br /> <br />* Cold water releases from the dam were credited with <br />reducing predatory nonnative carp and catfish from 80 percent <br />pre-dam to less than one (1) percent. <br /> <br />* Clear, cold water releases provided a habitat for formation <br />of a blue-ribbon trout fishery. This fishery reached its peak <br />under high fluctuating flows. <br /> <br />* The trout population in the Lees Ferry area was maintained <br />by artificial stocking. This population did not rely on <br />natural spawning to maintain its numbers. <br /> <br />, <br /> <br />" <br />, <br /> <br />* The trout population was not significantly affected by <br />stranding during receding flows but anglers were upset when <br />mature spawning trout became stranded. <br /> <br />. <br /> <br />, <br />< <br />f. <br /> <br />* Recreation use of beaches and shorelines from Glen Canyon <br />Dam to Lake Mead dramatically increased to 320,000 user days <br />per year since dam closure. <br /> <br />* River rafting increased from 205 to about 22,000 people per <br />year since dam closure. The latter figure is lower than the <br />demand due to restrictions on rafting use imposed by the Park <br />Service. <br /> <br />.1 <br /> <br />.-' <br /> <br />The changed conditions were beneficial to some components of the <br />ecosystem and detrimental to others. For native fish, the dye had <br />been cast when nonnative fish were introduced long before the dam <br />was built. Little scientific study has been done and little has <br />been written in the EIs about these relationships in the canyon <br />since dam closure especially regarding early life stage competition <br />and predation. Nonnative fish now play a major role in ecosystem <br />processes making it impossible to return to "natural" processes <br />under which native fish evolved. Rules of the game have changed <br />forever meaning the processes no lonaer operate nor can be made to <br />operate the wav thev did when the native fish evolved. Recognition <br />of the limitations in our ability to reconstruct natural processes <br />is lacking in the EIS and should be added. The EIs should discuss <br />whether these conditions represent the baseline which the <br />alternatives are attempting to change or whether these are the <br />conditions alternatives are attempting to protect. Also, if the <br />alternatives intend to change these conditions, what are the goals? <br /> <br />~~ I <br />" <br />~ <br /> <br />.~ <br />'- <br />.f' <br /> <br />~"': <br /> <br />4 <br />