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two other individuals less than 400 mm TL were detected in sampling in the 1990's that could be reasonably classified as wild fish. Regression of average annual length offish captured as a function of time resulted in a negative slope coefficient (-2.96, SE = 1.55, P = 0.07), which was heavily influenced by the few small fish captured in 1994 and 1995. In the absence of those few small fish in 1994 and 1995, average length offish in the middle Green River was similar over 1 1 1 i 1 time. The negligible changes in length of recaptured PIT-tagged fish from 1990 to 1999 suggested that razorback suckers in the Green River grew slowly overtime (Fig. 7). Changes in length between recapture intervals was generally less than 20 mm TL for most fish, regardless of the length of the recapture interval. Notably, two individuals which were at large 10 and 11 years, increased an average of 2 and 0.45 mm TL per year, respectively. Many fish apparently decreased in TL, which suggested measurement error. Abundance estimates.-Abundance estimates of adult razorback suckers calculated for pairs of sequential years from 1985 to 1992 averaged 456 animals (Table 3, Fig. 8 in part). Regression analysis did not detect a substantial change in average annual abundance over the same period (Table 4), although the coefficient was negative. We excluded the 1982 estimate which was based on only a single recapture to provide the most conservative trend analysis. Inclusion of that abundance estimate would have leveraged the slope of the regression coefficient substantially downward. Abundance estimates of adult razorback suckers calculated for pairs of years from 1993 to 1999 were reduced from earlier levels and averaged about 210 animals. From 1994 to 1997, captures and recaptures were particularly sparse so estimates in 1995 (1994 and 1995 year pair) and 1997 (1996 and 1997 year pair) were unavailable and estimates for 1994 and 1996 were 14