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oxbow lakes, former side channels in broad valley fIoodplains, ponds, and wetland depressions. During high flow events, some of these off-channel features were temporarily connected to the river in the past. These former natural riverine features could be integrated back into the historic floodplain by removing portions of man-made dikes or natural obstructions (e. g., gravel/sand bars). Background Although gravel pits are artificial environments that are typically diked and isolated from the mainstem river, they comprise a large proportion of pond habitats created by gravel-pit mining in the floodplain in some river corridors along the Upper Colorado River. Much of the floodplain habitat in the Upper Colorado River from the Colorado-Utah state line upstream to Rifle, Colorado, on the Colorado River and upstream to Austin on the Gunnison River has been modified by humans either from levee construction or mining gravel. There are four areas along the Upper Colorado River where gravel-mining operations have created numerous pits that vary in size, depth, shape, and orientation to the mainstem river: the Grand Valley between Palisade and Loma, Colorado (15- and 18-mile reaches), between Rifle and Debeque, Colorado, and near Delta, Colorado, on the Gunnison River. For example, Mitchell (1995) identified 243 ponds within 1 mile either side of the Upper Colorado River between Palisade and Loma. He calculated that these ponds totaled approximately 713 surface acres of standing water. Most of these ponds were created either from gravel mining or for sewage treatment plants. More importantly, these ponds are located in the former floodplain. Historical aerial photos of this same area reveal very little gravel-mining activity and ponds as late as 1954. In 1937 and 1954, there were no gravel pits in this reach and only 'virgin' floodplain existed where the 29-5/8 Road gravel- pit pond site occurs today. Even more dramatic is the approximate 15 miles of man-made dikes in this 33-mile stream reach between Palisade and Loma (Irving and Burdick, 1995) that effectively prevent inundation of potential off-channel habitats and fish access to historic floodplain habitat. During high flow events, some of these ponds have temporarily connected to the river allowing access to fish. However, these ponds that do not have permanent connections to the river have also trapped fish following recession of high flows. Ponds that are reconnected to the river are less likely to trap endangered fishes. Integrating ponds created from gravel-pit mining into the historic floodplain by removing portions of dikes, resloping gravel pits toward the river, and re-establishing connectivity to the river may provide off-channel habitats which are beneficial for effective management of the riverine ecosystem and recovery of endangered fishes. Most researchers believe that connecting isolated ponds to the river can be seasonally beneficial to endangered fishes. Ponds that are gently graded and connected to the river should be evaluated for their use and benefit for endangered fishes by providing off-channel habitats while reducing or minimizing proliferation of nonnative fishes that may compete with or predate upon endangered fishes. Valdez and Wick (1983) and Osmundson and Kaeding (1991) hypothesized that graded gravel pits that flood during runoff and drain with descending flow may benefit adult razorback sucker and Colorado squawfish by providing feeding, resting, conditioning, and possibly spawning areas. Habitat 2