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1 <br />1 <br />and regressed against each other. Estimates were made for ten-mile subreaches within the <br />' monitoring reaches and for each of the four monitoring reaches. Gmean CPE and total <br />number of fish were plotted for each year when divided into 10-mile subreaches and for <br />' three years combined when calculated for each monitoring reach. Histograms of Gmean <br />CPE, Total CPE, total number of fish, total area of backwaters (> 30 m2), and total number <br />of backwaters (> 30 m2) by 10-mile subreaches for each monitoring reach and each year of <br />' the study are provided in Appendix A (Figures Al through A6). <br />' When computed by 10-mile subreach, total number of fish and Gmean CPE were <br />significantly correlated (P < .1) with each other in all reaches during all years (Figures 4 and <br />5). The relationship in Reach 2 is based on only 3 data points (2 of which are zeros) each <br />' year, but relationships is the other monitoring reaches are based on at least 11 data points <br />each year (generally with at least one or two zeros). Reach 4 of the upper Green River, <br />' which is the reach where aerial video was first used to quantify backwater area (Pucherelli et <br />al. 1988), had the best relationships. Relationships in reaches 1 and 3 had more spread in <br />the data points, and thus lower correlation coefficients, but nonetheless showed weak <br />' correlations between the two variables. <br />' There was more variation in correlations between Gmean CPE and total fish for reach <br />wide data (Figure 6) than when calculated by 10-mile subreach. Reaches 1 and 2 had <br />' essentially no relationship between the two variables, with quite a bit of spread among the <br />data points. Reach 3 had a high correlation coefficient (r), but had two data points at one <br />end of the line and one at the other. Reach 4 had the best distribution of data points along <br />' the regression line, although its r value was lower than Reach 3. More data points would be <br />desirable to sort out the relationships in an analysis such as this, but each data point requires <br />' an extra year of data collection. <br />Total CPE was well correlated with Gmean CPE when compared by 10-mile subreach (r <br />' >_ 0.9 in 11 cases, r=0.8 in 1 case; Appendix Table A3) and by ISMP reach (r? 0.9 in three <br />out of four cases; Appendix Table A4). Therefore, its relationships with total fish by 10- <br />mile subreach and by ISMP reach were similar to those between Gmean CPE and total fish <br />(Appendix Tables A3 and A4). Gmean CPE and Total CPE were not correlated with total <br />area of backwaters within the same 10-mile subreaches (Appendix Tables A3 and A4). <br />' These poor correlations suggest that something other than (or in addition to) number or area <br />of backwaters is influencing the distribution of YOY Colorado squawfish. This is <br />' particularly apparent in Reach 2 which has quite a few backwaters, but very few YOY <br />Colorado squawfish. <br />13