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100 in 2002 and 2003, respectively. Abundance estimates in the Desolation-Gray Canyon reach of the Green River had relatively good precision in 2001 (CV = 16%) but relatively lower precision in 2002 and 2003 (CV's of 22 and 21%, respectively). The Desolation-Gray Canyon reach of the Green River consistently supported the highest average annual abundance of Colorado pikeminnow recruits during the study period. Recruit abundance was mixed over the study period at 163 (SE = 33) in 2001, 72 (SE = 28) in 2002, and 152 (SE = 44) in 2003; confidence limits for estimates in all years overlapped. Estimates of Colorado pikeminnow recruit abundance in the Desolation-Gray Canyon reach of the Green River were less precise than abundance estimates for adults, with CV's that ranged from 20 to 39%. Abundance of adult Colorado pikeminnow in the lower Green River reach was the lowest of all Green River reaches and similar to that in the Yampa River. Point estimates for adult Colorado pikeminnow abundance declined from 355 (SE = 56) fish in 2001, to 261 (SE = 51) in 2002, and to 227 (SE = 49) in 2003, a 36% reduction from 2001 to 2003. Overlapping confidence limits among pairs of point estimates did not suggest that any were statistically significantly different. Regression analysis of loge abundance as a function of time (N = 3) showed a negative relationship (loge abundance = 453.24 - 0.2236*year, rz = 0.955,p = 0.136). Numbers of unique animals captured declined from 143 in 2001 to 65 and 54 in 2002 and 2003, respectively. Lower Green River abundance estimates had only moderately good precision (CV's = 16 to 22%), likely due to the relatively small population present and low capture and recapture rates. Colorado pikeminnow recruits in the lower Green River reach were moderately common during the study period and ranged from 31 (SE = 13) in 2002 to 89 (SE = 27) in 2003, perhaps 29