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restoration of gravel pits may provide food that should increase survival of larval and juvenile endangered fishes. Graded gravel pits could function as seasonal, surrogate floodplain habitats for use by endangered and other native fishes. Protection, restoration, and enhancement of inundated bottomland habitat along mainstem riparian corridors are believed to be particularly important for recovery of razorback sucker. Before razorback sucker are reintroduced into historical reaches of the Upper Colorado River, reconnection of the river with the floodplain is essential. Reconnection of one of a few sites will not be adequate for improving survival of larval endangered fishes to aid in natural recruitment. Thus, additional floodplain sites will need to be identified and deve loped to provi de a seri es or "network" of off - channe 1 habi tats. The numerous gravel.pitponds have altered the natural floodplain by creating depr-essioos with irregular-shaped bottoms. Presently, floodplains contain primarily gravel-pit ponds that are deep. Therefore, habitat acquisition and restoration activities by the Recovery Program (U. S. Fish and Wildlife Service [FWS] 1987) will have to focus on such features in floodplains. Habitat development and enhancement is identified as one of the five principal elements of the Recovery Program for endangered fishes of the Upper Colorado River Basin. The overall goals of the Recovery Program are to restore, 1) restore razorback sucker and other endangered fishes in the Upper Colorado River in the Grand Valley, and 2) restore or enhance floodplain functions by connecting former floodplain to the river as habitat for the endangered fishes. A fi na 1 conceptual management plan was developed for Gardner Pond at 29 - 5/8 Road, adjacent to the Upper Colorado River, near Grand Junction, Colorado, describing alteration of this pond (Burdick 1994). Another pond, Hotspot Pond, is i rnmedi ate 1 y adjacent to Gardner Pond. The conceptual management plan described alteration of Gardner Pond and followup fishery studies of both ponds. The two ponds would be evaluated by comparing the seasonal use by native and nonnative fish. Hotspot Pond is sl ightly graded, slopes toward the river, drains mostly during low flows, and had been connected to the river for several years. Gardner Pond (unconnected to the river and not sloped) is an irregular.shaped depression that has been isolated from the river by a dike to protect former gravel-mining activities. The recommended alteration was to remove a portion of the dike at the downstream end between Gardner Pond and the river to form a channel that would connect this pond with the river to provide access for riverine adult razorback sucker, Colorado squawfish, and other native fishes. No alteration was planned for Hotspot Pond. Purpose and Objectives It is critical to determine if, graded ponds sloped toward the river that flood and drain seasonally, will be used and are more beneficial to endangered fishes than ungraded ponds that are perennially full of water (Valdez and Wick 1983). If isolated ponds are to be connected to the river as habitat for endangered fishes, careful consideration or evaluation of the pond's topography is crucial. For example, evaluations of use by both native and nonnative fish mi ght allow managers to make recommendat ions for pond design and out 1 i ne 3