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Ecology Five candidate sites were selected prior to the bottomland inventory and were proposed as sites to conduct demonstration studies aimed at testing hypotheses regarding flooded.bottomland restoration for endangered fishes. Wetland hydrology, water chemistry, and vegetation and invertebrate inventory studies were completed at these five bottomland sites in spring 1994. The studies were conducted at two sites along the Colorado River, in the Moab Slough bottomland site (Cooper and Severn 1994a), and at the 29-5/8 Road gravel-pit pond site (Cooper and Severn 1994b). The Escalante State Wildlife Area bottomland site (Cooper and Severn 1994c) on the Gunnison River and two sites along the Green River, the Escalante Ranch bottomland (Cooper and Severn 1994d) and one area within the Ouray National Wildlife Refuge (Old Charlie Wash [Woods Bottom] Cooper and Severn 1994e) were also studied. A conceptual plan was developed for each of these five sites that discussed experimental strategies, research, and evaluation that could be used to restore and enhance various types of bottomland habitats to assist recovery of endangered fishes. (Moab-Collins 1994; Escalante Ranch-Richardson 1994; Old Charlie-Modde and Irving 1994; Escalante State Wildlife Area-Burdick 1994a and 29-5/8 Road gravel pit pond-Burdick 1994b). Hydrology Stage vs. Discharge Relationship Hydrological parameters such as the timing, magnitude, and duration of flooding at a site are pivotal information to determine if a site is suitable for enhancement or restoration. This information was used to screen sites by determining how often or frequent does a site flood and how long (duration) does the site remain wetted following flooding. Temporary staff gauges were placed at seven bottomland sites adjacent to the Green River and at nine sites adjacent to the Colorado and Gunnison rivers to collect flow vs. elevation data from May through July 1994. These data would be used to establish stage vs. discharge relationships for each site and to estimate a range of flows necessary to inundate the bottomland site. Staff gauge placement corresponded nearest low areas along the river channel where water would enter into the adjacent bottomland areas. However, in some instances, the staff gauge was not placed at the lowest point because cameras would have been inundated at high water. Automatic, programmable 35-mm cameras were placed inside plexiglass-faced ammunition boxes and were aimed at each staff gauge to photo-document water level changes over time. Each camera was set to take pictures that ranged from 4 to 12 hours. Film was exchanged about every 10 to 14 days. The elevation of the top of the staff gauge was surveyed as a future reference point. Two ground reference control points were established at each site. In the Colorado and Gunnison rivers, the control point was arbitrarily set at a relative elevation of 1000.0 feet (305 m). In the Green River drainage, elevation control points were absolute (feet above sea level). Reinforcing rod with an aluminum survey cap served as the control point headpin. 12