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restored because of human alterations and the river system is rapidly approaching a new state such that the future of river bars and floodplain terraces is unclear. Restoration of large river ecosystems must be done with full consideration of the river continuum and flood pulse concepts (Walker et al. 1995). Walker et al. emphasize that the greatest conflict occurs between the supp 1 y and demand of water from dryl and ri ver systems and bel i eve that the integrity of large dryland rivers will be maintained only if users use water that is surplus to maintenance needs of the riverine ecosystem. In addition, site- specific restoration will not restore the ecological integrity of large rivers. For example, Theiling (1995) believed a larger ecosystem approach would be required rather thansite-specific efforts to restore the Mississippi River ecosystem. Although the precise physical, biological, and chemical conditions of flooded bottomlands needed as nursery areas for endangered fishes have not been documented, application of the match-mismatch principle provides some insight into environmental conditions that would be beneficial to razorback suckers (Table 3). The river elevation to provide an adequate frequency of inundation of bottomland habitats is considered to be 1 in 5 years (Table 3). However, long-lived fish species such as the endangered Colorado River fishes may only require inundation of floodplains in lout of 10 years to maintain self-sustaining populations. Strong year-classes occurred in the endangered fishes, probably as a life history strategy that evolved with a dynamic, highly fluctuating river environment. Captive-reared fish that are released into the river should be a minimum of 100 mm (4 inches) in total length (Table 3) to escape the majority of predation by nonnative fishes. A razorback sucker that is 100 mm TL would be able to escape the high predation that is likely occurring on larvae by the nonnative minnows, green sunfish (Leoomis cyanellus), juvenile smallmouth bass (Microoterus dolomieui), and juvenile largemouth bass (Microoterus salmoides). Carp (Cyorinus caroio) activity will increase turbidity in floodplain habitats that will decrease light penetration, adversely affecting plankton production and the food web. Carp were observed to occupy and feed on the rocky shorel ines of Lake Mohave where they were suspected to feed (i.e., prey) on the eggs and emerging larvae of razorback suckers (T. Burke, 1994, Personal Communication). These nonnative fishes were considered to be the most likely to adversely impact larval and juvenile razorback suckers in flooded bottomland habitats (Nelson et al. 1995). Many of the bottoml and habitats flooded ephemerally under hi stori c ri veri ne conditions. For example, a streamflow of 15,000 cubic feet per second (cfs) was estimated for overbank flooding at Escalante Ranch in the middle Green River (Cooper and Severn 1994b). That streamflow occurred 33 times during a 47-year period of record (1947-1993). The Escalante Ranch site was inundated 19 times by streamflows of 15,000 cfs between 1965 and 1993. The duration of inundation of the Escalante Ranch wetland occurred for 25 days only 13 times in the 47-year period of record. Cooper and Severn (1994d) estimated that streamflows between 17,000 and 20,000 cfs were required to inundate the floodplain along the middle Green River on the Ouray National Wildlife Refuge. A streamflow of 20,000 cfs occurred 17 times during the 47-year period of record (1946-1993) but only 7 times since the completion of Flaming Gorge Dam in 1964 (29 years). This 13