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Length-frequency distributions were developed by reach for all Colorado squawfish <br />collected. Mean total length and other summary statistics were developed for the four <br />reaches sampled. <br />Number of all species collected was totaled for the first seine haul in primary backwaters. <br />Gmean CPE was calculated for the three most common species in these collections. <br />Results and Discussion <br />Distribution and Abundance <br />Gmean CPE of YOY Colorado squawfish in Reach 1 of the lower Colorado River was <br />the highest observed in that reach since ISMP began (Figure 2; Table A-1). It was slightly <br />higher than 1986, the first year of ISMP, and slightly lower than 1985 when similar data <br />were collected by the Fish and Wildlife Service (McAda and Kaeding 1989). This peak in <br />abundance follows 1995 when Gmean CPE in Reach 1 was the lowest observed during <br />ISMP. YOY Colorado squawfish were distributed throughout the reach, with most fish <br />captured below RM 50 and a sharp peak in abundance between RM 40-50 (Figure 3; Table <br />A-2). No Colorado squawfish were collected in Reach 2 for the fourth year in a row. <br />In the Green River, Gmean CPE for YOY Colorado squawfish was somewhat higher than <br />1995 in Reach 3 and about equal with last year in Reach 4. Four extra samples taken in the <br />lower five miles of the Green River were included in calculations for Reach 3. This violates <br />the basic sampling strategy somewhat, but extra samples were taken by the Colorado River <br />sampling crew while waiting for the Green River. crew. The extra samples contained quite a <br />few more YOY Colorado squawfish than samples for the same five mile subreach taken <br />under the normal sampling strategy. Because of the difference between the two groups of <br />samples, it was decided that including all samples would be the most representative method. <br />Including the extra samples raised the gmean CPE for the reach from 0.81 to 0.88 fish/m2. <br />YOY Colorado squawfish were evenly spread throughout Reach 3, but exibited two peaks of <br />abundance in Reach 4 (Figure 3; Table A-2). <br />5 <br />