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_.-_..._-........~=_---'-'-_~"-~~~~_,~~~.::j,._:J-_-',,_.-_ .~ 23 RECOMMENDATIONS We recommend that the effect of fluctuating flows on backwater availability in the Green River be tested. Videography of three low flows of 1,000 to 1,200 ft3/s should be acquired. The first videography should be acquired during low flows at the end of the summer when they would have less jffect on young-of-the-year Colorado squawfish. Flows of 2,000 to 4,000 ft Is should then be introduced into the Green River for a week and then allowed to stabilize at low flow conditions when the next set of videography should be acquired. This process should be repeated a second time and a third set of videography should be acquired. Backwater availability should be quantified and compared for the three sets of videography to determine whit ~t fluctuatjng flows may have on backwater availabilit~. We recommend a riverine habitat monitoring program utilizing airborne videographYIMIPS techniques for the Green River from Island Park to its confluence with the Colorado River and for the Colorado River from the Redlands Diversion to it's confluence with the Green River. This should coincide with the Standard Monitoring fish sampling program currently in place. Monitoring studies will provide valuable information on backwater availability which relates to Colorado squawfish abundance, as well as other parameters such as channel width and side channel habitat. It is also recommended that a study determining the effects of flows maximizing habitat in the upper nursery be compared to the habitat formed in lower nursery (Mineral Bottom to the confluence). Higher flows at the Jensen gauge may be required to maximize backwater availability at Mineral Bottom at the expense of backwater availability in the upper nursery. Finally, we recommend that efforts be made to improve and refine the videography techniques being proposed for river monitoring. This should include testing of CIR videography and various image scales and tape formats. ACKNOWLEDGEMENTS This study was supported by Bob Williams and Reed Harris of the Upper Colorado Regional Office of the U.S. Bureau of Reclamation. A special acknowledgement is given to Dr. Harold Tyus and Mr. Kieth Rose of the U.S. Fish and Wildlife Service for assisting with the design of the study. The statistical guidance of Dr. Elmer Remmenga is greatly app~ pJ~r . 0-3700 0-3742 0-3744 (Pucherelli) 0-5150 D-7922B cc: