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and compared with Site 2 and the immediate river. 1 1 Site 2. Razorback sucker appear to be extirpated from the warmwater reaches of the Gunnison River, and reintroduction of this species will be required if recovery and monitoring are to proceed. The goal of any endangered species stocking effort is to establish self-sustaining populations. The widespread stocking of millions of razorback sucker in the lower Colorado River basin between 1981 and 1987 was unsuccessful (Minckley et al. 1991), and the stocking of 6,400 fin-clipped advanced fingerling razorback sucker in the middle Green River between 1987 and 1989 failed to produce any documented recaptures (Unpublished data, USFWS). Those stocking efforts were conducted without habitat modifications. The outcome of these reintroduction efforts indicated that the decline of the razorback sucker is not solely a problem of seeding, but rather, a wider problem associated with environmental changes. Thus, any stocking program to reintroduce the razorback sucker must be complemented with some form of habitat restoration and enhancement. The Recovery Program approved a plan (Burdick 1992) for the stocking of about 20 adult razorback sucker in the Gunnison River. This stocking is to gain biological information on survival, dispersal, and general movements, in addition to habitat use of riverine as well as off-channel areas. These 20 fish were surgically implanted with long-term (theoretical life expectancy, 4-years +) radio transmitters and were released 6 and 7 April 1994 between Roubideau Creek (river mile 50.5) and Hartland Diversion (river mile 59.9). Seven of these razorback sucker were stocked in backwater areas in the vicinity of the Escalante SWA. These fish are fully protected under the Endangered Species Act. The last known capture of a wild adult razorback sucker in 1981 was immediately upstream of the Escalante SWA at river mile 54.0 (Holden et al. 1981). The stocking of adult razorback sucker in 1994 will provide researchers with information regarding use of the present off-channel habitats and the newly reconnected off-channel habitats, such as at Site 2. In the future, trap nets could be set and run during the high flow spring period at Site 2 if other non- radiotagged fish are released in the area. Seasonal sampling of benthic invertebrates and zooplankton will be ' conducted to determine some dynamics of the food web. Specific scopes of work for biological monitoring and evaluation of this proposed habitat restoration project will be developed and reviewed through the Recovery Program. 1 1 22