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Ouray Bridge (RM 249). When a fish was recaptured, the marks allowed identification of the 5-mile <br />section or backwater where that individual fish was originally captured, capture history (e.g. if the fish <br />was recaptured repeatedly between passes or seasons), and the number of days between captures. <br />Winter Flow Fluctuations <br />Three distinct flow regimes for winters 1999-2000, 2000-2001, and 2001-2002 were proposed to <br />Bureau of Reclamation to evaluate the effects of fluctuating flows on the physical morphology of nursery <br />habitats (e.g., changes in area, water depth, velocity, ice cover) and fish inhabiting them. Flow regimes <br />for the first year were not manipulated but instead considered a stable flow regime. The second winter <br />called for a series of 5-d periods of daily fluctuations followed by a 9-d period of stable flows to produce <br />river stage changes at Jensen Gage (#9261000) of 0.10, 0.20, and 0.30. The final year of study proposed <br />a 90-d period of flow fluctuations at a level shown to invoke fish movement. <br />Winter Habitat Description and Winter Sampling <br />In conjunction with the proposed flow scenarios, a mixture of deep and shallow backwaters were <br />selected on the Ouray National Wildlife Refuge, a 12-mile section (RM 262-250) we call the Ouray <br />Backwater Complex. Each winter, two or three backwaters were chosen in close proximity to evaluate <br />effects of stage fluctuations. Three or four Optic StowAway® temperature loggers were placed into the <br />backwaters. A Trimble GeoExplorer IM Global Positioning System (GPS) unit was used to outline each <br />backwater and locate depth measurements, temperature loggers, and trap locations. Various fishing gears <br />were utilized to capture small-bodied fish prior to, during, and after ice cover. Gear types included fyke <br />nets, clover traps, minnow traps, and seines. An Aqua-Vu® underwater camera was used to monitor fish <br />presence and behavior under ice for 6 to 8 h between1400 h and 0900 h (refer to Report A for a more in- <br />depth discussion on methods). <br />viii