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i <br /> <br /> 4 Describe the relationshi between n o <br />p ursery habitat types available t and selected by <br /> Colorado pikeminnow. <br /> 5) Describe the relationship between degree-day accurriulation in main channel and nursery <br /> habitat azeas. <br /> 6) Determine the relationship between degree-day accumulation in all potential nursery <br /> habitat azeas and those utilized by young Colorado pikeminnow. <br /> 7) Determine the relationship between the quantity of nursery habitats available in the <br /> summer period to the number of young Colorado pikeminnow present in nursery habitats <br /> during the autumn period <br />8) Determine the usefulness of video imagery as a predictor of year class strength of <br />Colorado pikeminnow <br />9) Refine the interpretation of video so that "quality" nursery habitats can be distinguished <br />10) Compare intensive sampling data and the concept of habitat utilization to standardized <br />monitoring data to assess a) ways of refining standardized monitoring procedures and b) <br />ways of making greater use of the data currently being collected. <br />Geomorphology <br />METHODS <br />For 1993 and 1994, field, photographic and numerical computations were employed in <br />order to understand the effect of low- and flood-flow variation on habitat availability. <br />Geomorphic studies within a 1.5 km reach focused on a large, bank-attached compound bar and <br />were used to study the geomorphic processes that determine channel form and habitat <br />availability. Large-scale videography from a 10 km reach was used to quantify differences in <br />habitat availability at base flow in years with different flood magnitudes. The study reach was <br />located within the Ouray National Wildlife Refuge (NWR), Utah. <br />Channel response to flood passage was assessed at three scales. Detailed topographic <br />surveys of the study bar from two years showed the response of individual bed- and barforms to <br />flood passage, and were used to measure the change in habitat availability as a function of <br />discharge. Overlay maps of available habitat were created for each contour line of the detailed <br />topographic map. Area statistics from these habitat maps were used to create localized Habitat <br />Availability Curves (HACs) for 1993 and 1994. <br />Cross-section surveys within the 1.5 km reach were used to chazacterize patterns of scour <br />and fill during flood passage and subsequent low flows. The measurements were used to <br />calculate changes in bed elevation for individual cross sections, determine changes in sediment <br />storage, and as input to a numerical flow and sediment transport model developed by Andrews <br />and Nelson (1989), and modified by J. Nelson (pers. comm. 1994). <br />