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1 Abundance estimates calculated with data collected since 1992 suggested a substantial decline in the number of razorback suckers in the middle Green River when compared to earlier estimates. On average, the most recent and reliable estimates from 1998 and 1999 data suggested that only 116 (SE = 29} wild fish remained. Abundance estimates from 1985 to 1992 averaged 524 fish (Modde et al. 1996). Even recalculating those estimates with a revised data base that included more recapture records suggested that the population averaged about 456 fish from 1985 to 1992 (SE = 185). Those earlier estimates were mostly based on sampling fish only at the spawning bar upstream of Jensen, which may have under-estimated population abundance in the entire middle Green River reach. Captures made from 1996 to 1999 were from sampling that was more evenly distributed, and thus, it is likely that recent estimates more closely reflect the population in the entire middle Green River. We also considered that size-selective sampling may have biased low the number ofsmall-bodied razorback suckers available for capture and influenced conclusions about declining population size and lack of recruitment. We dismissed that notion because recently stocked razorback suckers that were relatively small were captured in Basinwide and other sampling in the Green River. Thus, we feel as though conclusions regarding substantially reduced population size were warranted. Given the low recapture rates and the small apparent population size, we urge that more reliance be placed on interpreting and reporting a range of possible abundance values (e.g. confidence intervals) rather than annual point estimates. We attempted survival-rate estimation from several different models. The Cormack- too sparse. The recaptures only model and Pradel's survival and population rate of change model Jolly-Seber model, which also permits abundance estimation, did not converge because data were yielded useful estimates of survival for this population. Estimates of ~ were relatively consistent 23