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WILDLIFE <br />Table 2D cont'd <br />p. 33 <br />Category <br />Minimum cfs <br />Interval <br />Source & Remarks <br />Least Tern and Piping <br />400 <br />non-summer <br />USFWS (1987b, p 35) <br />Plover <br />800 <br />summer <br />it if it <br />To maintain forage fish <br />for terns.° <br />Bald Eagles <br />1,100 <br />winter <br />NGPC (1985, p 36) and <br />NGPC (1985b, p 5) <br />For maintenance of open <br />water for feeding. <br />Waterfowl <br />No stream flows have been proposed specifically for meeting the <br />requirements of ducks and geese. <br />Fish <br />Discussions regarding habitat suitability index curve for fish (Fannin <br />and Nelson 1986) have not been translated into flow rate recommenda- <br />tions. USFWS is currently working on models for several fish species. <br />See also section on Least Terns, above, for discussion of forage fish. <br />Footnotes to Table 21) <br />A The Corps concluded that several studies "all independently indicate that a mean annual peak <br />flow of approximately 8,000 cfs is required to maintain the present braided reaches of the <br />river. The approximate duration of 5 days was selected on the basis of the historic pattern of <br />flows. The flow duration curve for Grand Island (1935 to 1979) indicates that flows greater <br />than 8,000 cfs presently occur about 1 to 1.5 percent of the time. Peak flows below 5,000 <br />cfs will lead to severe bank degradation and more rapid channel narrowing" (U.S. Army Corps <br />of Engineers 1988, p 9). "A duration of 5 days is needed to provide a beneficial effect from <br />the peak flows" (p 6). The Corps used instream flow study data, flow rates at the time of <br />maximum tree establishment in the Platte channel (1935- 1964), Karlinger et al. (1981), and <br />the analyses of Leopold and Wolman (1957), Williams (1978), and Ferguson (1984) to arrive <br />at their conclusion. "The above material ... is very persuasive" (U.S. Army Corps of Engineers <br />1988, p 10). <br />B After the often - discussed value of 3,800 cfs was "promptly dismissed" (see footnote "F "), "the <br />question of what discharge and duration would sustain the present channel conditions was <br />then entertained... The consensus of the group was 8,000 cfs for five days was necessary to <br />maintain the channel morphology" in the remnant braided reaches (O'Brien 1986, p 2). <br />C Although equations yield this and the next two values, "Additional information is required before <br />a minimum stream flow hydrograph to sustain the remnant braided reaches can be determined" <br />(O'Brien and Currier 1987, p 41). <br />