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<br />Draft Fmal Completion Report to UDWR for Contract #93-1070. Amendment 3 <br /> <br />20 <br /> <br />was used to assess habitat availability for large-scale remotely-sensed data, and a I.S-kIn reach within the lO-km reach <br />was used for smaller scale studies (Fig. 1). A small to large scale assessment strategy appropriate for the Green River <br />within Ouray NWR was implemented using the approach of Hill and others (1991). The geomorphology of nursery <br />habitat, the focus of this study, is of intermediate scale and addressed following the smaller scale "Habitat and Fish <br />Needs" component. <br /> <br />The Scale Appropriate for Assessing <br />Habitat and Fish Needs <br /> <br />IFIM was developed and validated for low flow periods in cold water streams, but the method has not proven <br /> <br /> <br />useful for warm water systems (Tyus, 1992). Consequently, empirically-based methodologies were employed to <br /> <br /> <br />determine small-scale habitat availability. For this study, the following habitat characteristics were quantified: <br /> <br />1) geomorphic setting, and maximum depth of individual habitats; <br /> <br />2) the relationship between area of available habitat and dischai-ge; and <br /> <br /> <br />3) the relationship between area and discharge as it changed from year to year. <br /> <br />Interpreted U.S. Bureau of Reclamation (Reclamation) video prints, taken during helicopter overflights taken at <br /> <br />base flow within the Ouray NWR, were used to deteJ:mine the geomorphic setting of individual habitats. Utah Division <br /> <br /> <br />of Wildlife Resources (UDWR) nursery habitat sampling data, taken in conjunction with the Reclamation video <br /> <br /> <br />overflights, were used to determine maximum habitat depth. Field mapping of habitat and flow patterns were used to aid <br /> <br /> <br />in interpretation of videography and delineation of individual nursery habitats. <br /> <br />Detailed topographic mapping and a stage-discharge relationship were used to synthesize the change in area of <br /> <br />available habitat as a function of discharge; maps made in the subsequent year were used to indicate the temporal <br /> <br />stability of the relationship between habitat availability and discharge. <br /> <br />Habitat Formation <br /> <br />The habitats utilized at low flows were created by bar and bank forms created by higher discharges, Bankfull <br /> <br /> <br />discharges are often assumed to control the form (for example, width) of the channel. Habitats for juvenile Colorado <br /> <br /> <br />SQuawfish were found at low discharges along the edges of bars and banks that were formed by higher discharges. For <br />