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Abundance of Colorado pikeminnow recruits (400 to 449 mm TL) per year over the period 2000-2003 varied from 130 (SE = 36) to 412 (SE = 51), and, on average, represented only 8.9% (4.7 to 13.3%) of the number of adults present in any given year. Estimates were variable over time and perhaps suggested a stable trend for Colorado pikeminnow recruits over the sampling period. Estimates of Colorado pikeminnow recruit abundance were less precise than river-wide abundance estimates for adults, with CV's that ranged from 12 to 27%. Survival estimates.-The best AIC model suggested a constant survival rate S for Colorado pikeminnow over the study period (Fig. 9) with a TL, TLZ, and TV terms (parameters and SE's for the function of logit S are intercept = 0.6173, SE = 0.1370; TL = 0.5606, SE = 0.2373; TO = -0.2068, SE = 0.1140; TV = -0.1320, SE = 0.0665), where survival was relatively low for fish about 350-mm TL, increased for fish up to about 600-mm TL, and then declined rather dramatically for larger fish. Average S adjusted to the mean TL for Colorado pikeminnow across all river reaches was 0.65 (95% CI, 0.586 to 0.708) for the 2000-2003 study period (Table 10). We fully investigated the apparent phenomenon that larger fish had poor apparent survival in this study with many different analyses but survival estimates for large fish consistently approached zero. Analysis of the capture history records for the 18 Colorado pikeminnow 800-mm TL or larger suggested that only two were recaptured after initial capture during this study, and both recaptures occurred within the same year. Because only recaptures across years contribute to survival analyses, this was the cause for declining survival relationships for larger fish, compared to those for 1991-1999. If some of those fish are captured in years after 2003, survival rates for that size-class may increase. Average S for Colorado pikeminnow captured during ISMP sampling from 1991 to 1999 was 0.82 (95% Cl 0.709 to 0.891), higher than that observed for 2000 to 2003. The shape of the 31