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34 In contrast, the river reach below Cross Mountain Canyon contains few backwater habitats. The Little Snake River enters the Yampa at river km 82 (mile 51) and provides numerous eddies, sand islands and bars. The Yampa River between the confluence with the Little Snake and the entrance to Yampa Canyon (river km 74, mile 46) is characterized by sand deposition and braided channels. Fish numbers 1, 2 and 3 implanted below Cross Mountain Canyon used predominantly eddy, run, and side channel habitats. The fish implanted above Cross Mountain Canyon, where more backwater habitats are located, accounted for the high percentage of backwater use reflected in Figure 5. In 1982, work conducted by the U.S. FWS on the Colorado River indicated that gravel pits, similar hydrologically to some backwater habitats, were used by both Colorado squawfish and razorback sucker (Miller et al., 1983a). Thirty-six Colorado squawfish were collected from four gravel pits, 23 were captured in Walter Walker Wildlife Area (WWWA), just west of Grand Junction, where most collecting efforts were concentrated. In late June and early July, when water levels began to recede, 13.Colorado squawfish were captured in fyke nets as they were apparently leaving WWWA. When significant reductions in water levels threatened to isolate the gravel pits, squawfish left the habitat as evidenced by lack of squawfish in collections in isolated gravel pits or connected pits during low water. Movement patterns of 16 radiotagged Colorado squawfish were monitored in the Grand Junction area by USFWS in 1982. Twelve fish were collected in gravel pit and backwater habitats while four were collected in river habitats. The fish from WWWA exhibited the most dramatic movement patterns migrating both upstream and downstream. These observations on habitat use and subsequent