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<br />. <br /> <br />. <br /> <br />accurate assessment of annual reproduction and <br />recruitment of young. <br />Sampling of adult Colorado squawfish immediately before <br />and during spawning and of larval Colorado squawfish in <br />backwaters should be minimized to reduce disturbance and <br />sampling mortality. <br />Collection of life-history, abundance (using marked or <br />tagged fish), and fishery-type data on all fishes <br />(including non-natives) is important. <br /> <br />Elements of the SDCR - Five Year Research Effort <br /> <br />ELBKENT 1 REPRODUCTION. This element addresses <br />hypotheses 2, 3, 4, 8, 9, and 10. Objectives of the <br />related study ("Annual assessment of Colorado squawfish <br />reproduction and larval abundance in the lower Yampa <br />River, Colorado, and the lower Green River, Utah") are <br />to use collections of drifting larvae to document <br />Colorado squawfish spawning, determine peaks in relative <br />abundance of drifting Colorado squawfish larvae, and <br />determine the relative abundance of Colorado squawfish <br />larvae transported into nursery habitats. <br />Reproduction will be assessed using drift-net <br />sampling at two sites: one in the Yampa River immediately <br />upstream of the Green-Yampa River confluence (covers <br />Colorado squawfish produced in the Yampa River; site used <br />in past sampling) and another in the Green River below <br />the Desolation-Gray Canyon Colorado squawfish spawning <br />area. Near-shore drift-net sampling (using flow-metered <br />nets) will be conducted daily at dawn during late June- <br />early August. Samples will be preserved in ethanol to <br />allow for subsequent ageing using otoliths (determination <br />of spawning times). <br />Data gathered from this study will provide <br />information on relationships between relative <br />reproductive success and annual flow regimes, and a <br />relative measure of input into downstream nursery <br />habitats (e. g ., Jensen-Ouray area and Mineral Bottom <br />area) . <br /> <br />BLEMENT 2 - AGE-O SURVIVAL TO FALL (aqe-o recruitment). <br />This element addresses hypotheses 3,6,7,8,9 and includes, <br />at this time, two studies (1) "Availability and quality <br />of nursery habitat" and (2) "An evaluation of Colorado <br />squawfish recruitment". Aspects of the study to evaluate <br />Colorado squawfish recruitment also relate to ELEMENT 3. <br />The study on availability and quality of nursery <br />habitat will be conducted in the Jensen-Ouray and Mineral <br />Bottom areas (Green River). Objectives are to determine <br />relationships between habitat availability at recommended <br />summer/fall flows and habitat utilized by young Colorado <br />squawfish and their relative abundance, assess utility of <br />video imagery to predict year-class strength of Colorado <br />squawfish and ways to refine interpretation of video, and <br />