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22. habitat delineation and MIPS software. We believe this study represents a worst case scenario for accuracy and precision and although the results were acceptable, future studies will provide more accurate information as researchers become familiar with videography/MIPS procedures. The advantages of videography over aerial photography include (1) lower imagery cost, and (2) a live or real-time image display which allows ground truthing in the same time frame that imagery is collected. Another advantage of videography for riverine habitat monitoring is the ability of-- the video camera operator, or their assistant, to annotate the videography as it is being flown with audio information on the number and location of backwaters or other features as the imagery is acquired. This would allow~ more accurate delineation of questionable backwaters or flow through areas. Real-time imagery also allows for scale and exposure adjustment in flight as well as allowing the video operator to determine if a site has been completely covered. By contrast, aerial photography may not be available for 2-3 months and any coverage problems would have no or very expensive solutions. The turnaround time for a given project would be significantly less with the application of a videography/MIPS system. The use of videography/MIPS is not being suggested as a universal replacement for aerial photography/GIS. The MIPS system does not store data in a geographically referenced system as does GIS. Additionally, production of large, detailed multi-color habitat maps are not possible with MIPS. We are currently investigating how the resolution of videography can be optimized through the use of professional video cameras, various tape formats (e.g., super vhs), high quality monitors for video image analysis, and the optimum combination of aircraft elevation and camera focal length. The use of a digitizing puck and board will improve the precision of backwater delineation on videography over the current use of a mouse. CONCLUSIONS Aerial photography and videography can be used successfully to determine backwater availability in the upper Colorado River Basin in response to varying flow regimes. These techniques should also be applied to future riverine habitat monitoring programs for the Green and Colorado Rivers. A flow range of 1,000 to 1 800 ft3 s at the USGS Jensen auge will produce more bac wa er area an numbers on e UDper Gr~~n River. ows a ove 1,800 ft3/s had a detrimental effect on backwater development under our study conditions. A gradually decreasing hydrograph during summer months appears to be a required condition for maximizing backwater availability. High flows may be required before young-of-the-year Colorado squawfish enter the system to maximize backwater availability. Backwaters are much more numerous and substantially larger in the Green River above Desolation Canyon than below it. The upper nursery area (Tyus et a1. 1987) had the greatest amount of backwater habitat.