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majority of these fish were captured in Etter Pond near Debeque, Colorado. These fish were determined from genetic analyses to be progeny from a few adults that gained access to Etter Pond during the high spring flows of 1983 and 1984. In the Upper Colorado and Gunnison rivers, too few adult razorback sucker remain to re-establish or to sustain stable populations in the riverine system. Although limited recruitment may be occurring, it is not sufficient to maintain populations in either river. Only a few juvenile razorback suckers with a substantiated identification have been collected from the upper Colorado River Basin. Smith (1959) reported two razorback suckers (about 38 mm TL) from Glen Canyon during a preimpoundment study. Taba et al. (1965) collected eight juvenile razorback suckers (90-115 mm TL) from a Colorado River backwater downstream from Moab, Utah. In 1991, two juvenile razorback suckers were collected from the lower Green River (Gutermuth et al. 1994). Remaining razorback sucker populations are composed exclusively of old adults in the Upper Colorado and Gunnison rivers. Although the causes are not known, recruitment failure may be due to deterioration of water quality or predation on eggs, larvae, and juvenile razorback suckers by nonnative fish. In addition, the reduction of high spring flows has altered the natural flooding cycle, and some investigators (McAda 1977, Tyus and Karp 1989; Osmundson and Kaeding 1991) attribute lack of recruitment, in part, to the reduced availability of inundated floodplains which historically provided spawning or nursery habitat. Factors affecting survival of razorback sucker in the riverine system must be determined before large-scale augmentation or re-introduction stocking efforts can be expected to be successful. A plan to evaluate stocking to augment or restore razorback sucker in the Upper Colorado River (Burdick.1992) was accepted by Recovery Program participants. That plan proposed stocking small numbers (10-20 adults per experimental stocking site) of hatchery- or pond-reared fish to obtain information on: 1) dispersal, movement, and distribution following stocking; 2) survival of hatchery or pond-reared fish; 3) habitat use; 4) potential spawning areas; and 5) growth. That plan was partially implemented. In the spring of 1994, 41 adult razorback sucker were captured from Etter Pond near Debeque, Colorado, and implanted with 4.5-year radio transmitters. Twenty radio-tagged razorback sucker were stocked in historical habitat in the Upper Colorado River between Debeque and Rifle, Colorado, and 21 were stocked in the Gunnison River in the floodplain reach near Delta, Colorado. Preliminary results from this study suggest that post-stocking survival was less than desired. In September 1995, five of those fish were still alive. Two additional fish are contacted intermittently and may still be alive. An additional four adult razorback sucker from Etter Pond were radiotagged in March and held in the refugia ponds at Horsethief State Wildlife Area (SWA) until they were released in the Gunnison River in September 1995. Monitoring of these fish is ongoing. Burdick (1992) addressed the essential elements for an experimental stocking program to obtain fundamental information on the ecology of razorback sucker and to determine the feasibility of stocking as a recovery tool. The plan discussed the rationale and justification for experimental stocking, the genetic risks associated with experimental stocking, justification for 2