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<br />substantially over capture-recapture intervals during the 1991-2003 period, which may have <br />biased size effects over time. <br />Finite population rates of change (1) estimated for the period 1991 to 2003 suggested a <br />long-term expansion in abundance of Colorado pikeminnow in the Green River Basin up to year <br />2000 because Xi was > 1 every annual interval except for 1996-1997 (0.80) and 1998-1999 (0.99) <br />(Fig. 12). Confidence limits about the estimates were typically wide. For all three annual <br />intervals between years of abundance estimation sampling from 2000-2003,,X was < 1 and the <br />upper bounds of confidence limits did not include one in any of the three periods. <br />ISMP catch/effort trends, 1991 to 2003.--Catch/effort indices at standard ISMP sites for <br />Colorado pikeminnow in the four reaches of the Green River Basin were variable but generally <br />increased up to year 2000 (Fig. 13). White River catch/effort indices were particularly variable, <br />as they varied by almost an order of magnitude over the duration of ISMP sampling. Catch/effort <br />indices were highest for the White River and middle Green River reaches and lower for the <br />Yampa River and the lower Green River reach. If catch/effort indices reflected population size, <br />Colorado pikeminnow abundance in the Green River Basin appeared to increase rather <br />dramatically from 1991 to 2000, particularly in the middle Green River and the White River <br />Catch/effort data suggested that abundance of Colorado pikeminnow in the Yampa and lower <br />Green River reaches increased at a slower rate up to 2000. Similar to abundance estimates and A, <br />catch/effort indices for Colorado pikeminnow after 2000 declined in all river reaches. <br />Correlation of annual abundance estimates and ISMP catch/effort indices for all river <br />reaches combined (n = 15, none for Deso-Gray reach) from 2000 to 2003 suggested a positive <br />and moderately strong relationship (r = 0.70, p = 0.005). Correlation coefficients for annual <br />abundance estimates and ISMP indices for individual river reaches were relatively strong for the <br />36 <br />r