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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />OOJuu6 <br /> <br />years, and an increase in island area (Kirchner and Karlinger 1981), Since 1909, <br />climatic conditions in central and western Nebraska have remained fairly <br />uniform, but peak and mean annual discharge in the Platte and North Platle <br />rivers have decreased significantly (Williams 1978), <br />A large portion of the research conducted for future projects along the <br />Platte River system has been devoted to determining flow requirements for <br />different aspects of river ecology. The recommended instream flow rates for <br />different periods throughout the year varied greatly for three separate projects <br />(Catherland. 1983; Two Forks, 1987; Prairie Bend, 1989), The comparison of <br />flow recommendations for these three projects are given in Table 1 below. <br /> <br />Table 1 Comparison of Flow Recommendations <br />for Proposed Projects along Platte River <br />Project Migration Flows Wet Meadow Channel <br />Mar. 22-M~v 10, spong Maintenance flows Maintenance flows <br />Sept. 2O-Nov. 10 r~lI <br />Catherland note 1) 1700 cIs 1100 cfs 3800cfs for 23 days <br />Two ForXs (note 2 1200 cfs 1100 cfs 8000cfs for 5 days <br />Pralne Bend (note 2) 2000 cfs 1100 cfs 8000cfs for 5 days <br />Note 1: data found in EA Eng, Sci. and Tech 1983 <br />Note 2: data found in Bowman and Carlson 1994 <br /> <br />The recommendations in Table 1 were suggested in order to maintain or create <br />the ideal habitat conditions as previously discussed, The only apparent <br />consensus between the studies was with the 1,100 ds recommended flow for <br />wet meadow maintenance. During February to early May, wet meadows should <br />be maintained If a flow of 1.100 cis is provided (USFWS 1990), Another <br />recommendation of 2.000 cis for migration flow was made by Faanes and <br />Bowman (in press), They reported that flows of 838 to 5.150 cis existed in the <br />Platte River on 16 dates when whooping cranes occupied the Big Bend reach of <br />the Platte River. Ninety percent of the whooping crane use occurred when flows <br />were greater than 1,200 cis, The mean flow dunng all confirmed sightlngs of <br />whooping cranes was 2.683 cis, The recommendation of 2,000 cis by Faanes <br />and Bowman was based on (1) eXisting habitat conditions. (2) present <br />population levels of the whooping crane. (3) knowledge of the species <br /> <br />. <br />