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CSy be conducted to determine other possible factors that could be limiting recruitment. The information obtained from pilot studies at demonstration sites will provide useful information for selecting other future sites for restoration. 1. Select flood plains as experimental monitoring units that cover a variety of features and have natural or managed access to the river. Provide mainstem flow connections to currently blocked historical off-channel habitats, e.g., gravel pit ponds by mechanical excavation. Monitor water levels and area flooded (using aerial photos); monitor short- and long-term changes in flood plain and adjoining channel geomorphology. 2. Utilize existing (or create) drainable flood plain ponds with inflow/outflow control from which all non-native fishes can be eradicated and excluded. Stock with larvae collected from natural reproduction ,(Green River). Rear them to a size that allows individual tagging (e.g., PIT tags) and release them into Green and Colorado rivers. 3. Study the annual and seasonal use of non-native fish in gravel pit ponds with different configurations and slopes. Compare non- native and native fish use in two ponds adjacent to each other and that are both connected to the river--one that is 'bathtub' shaped and that will hold water year round and one that is slightly graded toward the mainstem river but will hold water seasonally. Determine if a gravel pit pond gently graded toward the mainstem river will adequately fill during spring high flows and drain during recession of flows in the summer. Determine which pond configuration and bottom shape will reduce or eliminate non-native fish that are thought to adversely impact endangered fishes. IV. Description of past performance on this or similar project. In the Upper Colorado River, there has been little resear-ch and management activities aimed at reconnecting historic flood plain habitats to the mainstem river to benefit endangered fishes. Moreover, from the literature, it appears that there has been few attempts to restore historic flood plain habitat in other river systems. Therefore, many of the strategies proposed for restoring flood plain habitats in the Upper Colorado River Basin will be untested; initially, some may not work, but certainly an adaptive management approach must be used to determine those strategies that will be best suited for the particular site and its configuration. In the Green River, Old Charley Wash (Wood's Bottom) was reconnected to the mainstem and is a pilot project currently underway to test the hypothesis regarding flooded bottom land restoration for razorback sucker. Wydoski and Wick (1994) have developed an issue paper, "Enhancement of Flooded Bottomlands and 2