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1 calculate abundance estimates. We expended considerable effort attempting to ensure that all tagging records were included and to ensure that capture histories offish tagged with both carlin and PIT tags were merged. The few additional records that were matched with this effort are potentially important because longer capture histories may affect survival-rate estimates. Most additional data were obtained from the centralized database maintained by the U. S. Fish and Wildlife Service, Grand Junction, Colorado or from Modde et al. (1996). There were also several "re-discovered" recaptures from the years 1990 to 1992 (mostly fish for which carlin- and PIT-tag capture histories were not matched together), the last years for which abundance estimates were produced by Modde et al. (1996). These are important because the entire data set is sparse and overlooking just one or two individuals will bias abundance estimates based only on a few recaptures. We were interested mostly in captures of wild fish so we could ascertain the status of that portion of the population. Hatchery-reared fish released into the Green River from 1996 to 1999 were also captured in Basinwide and other sampling programs. We made a concerted effort to segregate wild from hatchery-reared and released fish but it was often difficult because we were uncertain if all released fish had been recorded in a database and reported. We also had difficulty tracking the status of wild fish taken to the hatchery for brood stock and when, if ever, they had been returned to the river. For example, one individual was captured in the vicinity of the spawning area in 1989, 1992 and again in 1993 when it was removed from the river and held in captivity. There were no other records of this animal, including a date of repatriation from the hatchery, until it was recaptured again in 1998 and 1999. Finally, there was uncertainty regarding numbers, release locations, sizes, and tag status ofhatchery-reared razorback suckers released into the Green River and associated flood plain habitat. Abetter system for tracking re- 7