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~ } <br />years (scope of work entitled Flow effects on young_-of-the-year Colorado <br />sguawfish). These studies will be evaluated this year. Over-winter mortality <br />is undoubtedly important in at least some years, and should continue to be <br />investigated. In addition, there may be a general downstream movement pattern <br />of small Colorado squawfish that could carry them into Lake Powell and further <br />reduce their chance of survival. This movement pattern should also be <br />evaluated. <br />Reproductive success should also be measured by sampling for larvae. <br />Several years of river wide, larval dip-net samples have already been <br />collected--th.is sampling should continue. However, the dip-net samples should <br />be supplemented by drift net sampling at several strategic locations. Current <br />data indicate that Colorado squawfish spawn at many scattered locations in the <br />Colorado River between Grand Junction, Colorado and Lake Powell, Utah. <br />However, the majority of larvae and young-of-the-year Colorado squawfish are <br />found in the lower 100 miles of river. The larval sampling program should <br />attempt to determine where these larvae are produced. The Larval Fish <br />Laboratory will be writing a discussion paper on larval sampling techniques <br />and interpretation of results (scope of work entitled Position paper on <br />studies to evaluate movements of Colorado squawfish larvae throughout the <br />Upper Colorado River Basin). The results of their analysis will be important <br />to developing an appropriate sampling design. <br />Non-native fishes are also counted during the fall seining done by the <br />Interagency Standardized Monitoring Program. However, nonnative fish are only <br />counted in one-quarter of the seine hauls taken. Evaluation of the size of <br />the non-native fish community should include counting all fish in all seine <br />hauls and categorizing them by size class--at least young of the year and <br />35 <br />