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3. Use the information collected to: (a) assist with the process of making year-round flow recommendations far the Gunnison River and (b) assist with identification of areas that might be appropriate for habitat- improvement projects. Methods Sfudy Area Five study sites were selected within the portion of the Gunnison River currently occupied by Colorado squawfish (Figure 1; Table 1). The study sites varied from 0.5 to 1.6 mi in length and were selected to represent the range of macro habitats available in the Gunnison River. Two sites (1, 2) were selected because of Colorado squawfish use documented by Burdick (1995) and one site (3) was chosen because general features of the site resembled reaches of the Green or Yampa rivers known to be spawning sites used by Colorado squawfish. One site (4) was chosen because it was also being used in a study conducted jointly by Reclamation and the U.S. Geological Survey (USGS) and the last site (5) was chosen because it represented floodplain habitat. The joint Reclamation-USGS study investigated flows necessary to move sand, silt, and larger particles from the bed of a regulated river (Milhous in press). The five sites composed a relatively small portion of the Gunnison River, but represented all macro habitats found there. Habitat Mapping Reclamation videotaped the Gunnison River from a helicopter flying along the river corridor at a constant elevation of 2,000 ft. A continuous image of the river was acquired from its mouth to Austin, Colorado (65 mi) using a Sony DXC M7 CCD video camera with a 12:1 zoom lens set at full wide angle. The imagery was recorded on a Sony 3/4-in VO 8800 Umatic SP recording deck. Most of the river was covered by a single upstream pass. However, the wide river channel and extensive floodplain in Escalante State Wildlife Area (SWA; Site 5) required three different passes to capture the different river channels and all floodable areas on the video. A total of seven flights were made at river discharges ranging from 981 to, 15,800 cfs. The entire study area was videotaped in 1 day at each flow level. Surface habitat was mapped by a ground crew at the same time as the helicopter flight. However, it took the ground crew 2 days to map all five study sites at each river flow. Usually the four lower sites were mapped on the first day and the much more complicated Site 5 was mapped on .the second day. The senior author did all habitat mapping to ensure consistent habitat classification among study sites and river flows (Roper and Scarnecchia 1995). The water surface at each of the 3