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<br />- Mean ISMP catch rates of Colorado ikeminnow were consistentl hi er than <br />P Y ~ <br />intensive sampling catch rates because quality habitats were targeted by ISMP. <br />- The sam 1' <br />p ing efficiency study showed that ISMP samphng was a good estunator of the <br />composition and relative abundance of the common fish species. <br />- There was no significant difference between fish species percent composition between <br />the initial seine hauls, and that present in total, except for channel catfish, which were <br />consistently under-represented on the first pass. <br />- Species diversity was greater in total than in the first pass. However, additional species <br />were represented by incidental catches of few individuals of 1 to 4 species. <br />- Colorado pikeminnow were collected in the first seine hau182% of occasions where <br />they were present in the habitat. <br />- ISMP sampling was not representative of the other native fishes which do not <br />preferentially use backwater habitat. <br />- Initial capture probability (C(p) averaged 53%. An average of 54.7 % of fish were <br />removed in the first seine haul, and an average of 78.4% were removed by the third <br />pass. <br />- Initial capture probability did not seem to be affec*.ed by seining difficulty, except in <br />habitats with obstructed substrates such as weeds or large rocks. <br />RECOMMENDATIONS <br />Flow Levels <br />Peak discharge: Infre uent hi floods lar er in ma 'tude than the 1993 eak are ne <br />' q ~ g ~ p cessary <br />to maintain channel form and rebuild bar topography. The practice of matching the timing of <br />Yampa and Green River peaks to augment flows should be continued in order to maintain in <br />channel habitat for young of the year Colorado pikeminnow. Moderate peaks rearrange <br />deposits and increase the complexity and habitat availability. Low peaks should be <br />augmented, but the duration should be limited for those flood discharges less than bankfull, <br />but greater than bar top, stage. <br />- A moderate year, in which peak discharge is near average, flow declines quickly and <br />stabilizes, temperatures rise early, and habitats are stable, is likely to offer the most favorable <br />conditions for both good production and subsequent recruitment into the age one group. The <br />recommendation is to manage the river system as naturally as possible, in order to take <br />xix <br />