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within 40 RM below the release site, with the remaining 15% distributed fairly evenly down to the confluence of the Colorado. The pattern was similar on the Colorado River where 94% of all bonytail captures occurred within 30 RM downstream of the release site. Overall, it would appear that juvenile bonytail are not entering the higher gradient canyon sections, which confine the two flat-water sections in which they were released. This is further supported by ISMP sampling and population estimates for humpback chub in Westwater (1997-2000), Cataract (1998-1999), and Desolation/Gray (200 I) canyons, in which yielded no stocked bonytails. One adult bonytail (TL 370 mm) was captured in Gray Canyon (RM 148) during the 2002 humpback chub population estimate. A total of 49 adult sized bonytail (TL >300 mm) were implanted with radio tags in the Colorado and Green rivers during 1997-2000. The overall survival of radio-tagged bonytail was excellent throughout the study. Only one of the 49 bonytail implanted was suspected to be deceased before tag failure. Survival of the bonytail was confirmed via daily movements throughout the life of the tags or until the fish had moved out of monitored areas. This was a vast improvement over the confirmed mortality rate of 74.4 % experienced by Chart and Cranney (1993) during the tracking of 86 bonytail in 1988 and 1989. The most important variable affecting survivorship of radio-tagged fish was likely age at release. For bonytail tracked in the Colorado and Green rivers specific habitat locations were recorded for 574 contacts. Many habitats were utilized throughout the study period, however, we believe that after the period of acclimation adult bonytail were selecting areas which offered a combination of eddy and run habitats. Each year bonytail showed a basic pattern of being sedentary for the first month following release, then increasing in both longitudinal and local activity during periods of spring runoff, and finally moving back upstream to areas which offered eddy/run habitats. Although downstream movements up to 113 river miles were observed radio-tagged fish generally remained within 20 river miles of their release sites and all remained within the flat-water section in which they were released. Final recommendations include the following: 1) stock hatchery-reared bonytail in the Colorado, and Green, rivers at a target size of 300 mm, 2) mark all hatchery-reared bonytail with PIT tags prior to release, 3) stock bonytail in March to early April to allow for an adequate acclimation period. 4) monitor stocked bonytail in mid-April to early June, and utilize electrofishing as the primary monitoring method. 5) monitor for successful bonytail reproduction, and 6) any further investigation of flow training should occur at Wahweap State Fish Hatchery. Keywords: bonytail, Gila elegans, stocking, reintroduction, monitoring, telemetry, Colorado River, Green River IX