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survival of age-O razorback sucker. Below are three management options for depression wetlands: a) Provide water control and draining capability to a few large, naturally connected wetlands that will maintain water elevation through the summer allowing rearing of wild razorback sucker and removal of nonnative fishes simultaneously. Benefits of this option are that fish could be reared, counted and introduced directly into the Green River (following establishment of trends, counting and segregating native and nonnative fish may not be necessary). Given the high percent of nonnative fish biomass that access wetlands, periodic removal of nonnative fishes would offer a significant, if not the major opportunity to remove nonnative fish from the Middle Green River. A disadvantage of this option is construction cost. Given current knowledge, the cost of a future structure would be significant, but less than the one constructed in 1993/5. Labor costs to collect and sort fish would be minimal and not required annually. This approach would represent an intervention effort that would assist the population in increasing its abundance on a short-term basis, but is probably not the answer to long-term sustainability. b) Depression wetlands could be partially breached so that flows enter the wetland more regularly and fish have access to the river in their second or third year of life. Flo Engineering (1996) indicated that excavation in the Ouray area could result in floodplain inundation similar to historical frequency. Thus, depression wetlands would still exist, but would not be as deep. The advantages of this approach is that wetlands would be connected to the river more frequently and for greater duration. If the dikes on wetlands were lowered to allow connection to the river at382 m3/s, differences in time between floodplain isolation (from receding river elevation) and most backwater appearance in the Ouray area of the Green River would have been reduced from 36 d to 30 d in 1995. In 1996, the first razorback sucker larvae in the river would have had access to floodplains for 12 days (larvae were first collected on June 3 with the last larvae captured June 27 and flows receded below 382 m3/s on June 15). Under this management option, the wetland would probably dry more frequently, increasing its productive capacity by aerating soils (i.e. moist soil management). A disadvantage of this approach is that water levels may decline during the late summer to the point where water quality and fish survival are threatened during either the summer or following winter. In 1994, if water had not been supplemented in Old Charley Wash, fish probably would not have survived through the summer. Thus, this option would only be preferable for sites that could maintain adequate depth through the summer and may only be suitable during high flow years. Another potential disadvantage may be contribution of nonnative fishes into the main channel in the following spring when the wetland is connected. 2. The long-term solution to razorback sucker recovery is habitat availability. The connectivity and maintenance of floodplain habitats is dependent on the frequency, 47