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Colorado squawfish use when compared to unsued backwaters. <br />~' Although correlations were questionable, both species appear to be adversely impacted by <br />'~ periods of extended high flows. -Flows did not a ear however to affect backwater avail ' <br />~. PP ability. <br />Extended high flows did show some negative impact to scour (secondary channel) backwaters, <br />which aze often large and deep. Idiigh flog sampling periods decreased the numbers of <br />shoreline eddies. Shoreline eddies, however, could be of any size and depth. <br />Because of the restricted nature of the Green River in these canyon reaches, backwaters <br />are laz~ely permanent fixtures. River flows impact size, depth and other characteristics because of <br />resultant river levels, but they do not create and destroy backwaters as often or readily as occurs <br />in floodplain meanders (such as the Jensen to Ouray reach). <br />1) Because of the appearant negative impact of extended spring flows on chub and <br />Colorado squawfish CPUE, scour (secondary. channel) backwaters and shoreline <br />eddies, it is recommended that duration of peak spring flows be moderated to <br />benefit these species. (One trade-offto consider, however, is that the same <br />. extended flows appear to negatively impact red shiners and fathead minnows and <br />---~ <br />_ may be useful in controlling their numbers.) <br />2) Maintaining summer and late season flows at a moderate level (below 4000 cfs and <br />above 1500 cfs) may provide the most stable backwater habitat distribution. <br />Under this scenario, the backwaters available (which tend to:be permanent}will be <br />larger and deeper; two qualities for which chubs and Colorado squawfish seem to <br />select for. <br />3) YOY chub numbers and incidence were highest in Desolation Canyon (above RK <br />249.4), indicating that spawning sites were restricted primarily to this reach. <br />30 <br />