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<br />A -\ <br /> <br />water control structures, to hold water during the growing season. Some <br />sites will also have inlet water and fish control structures. Prior to <br />spring runoff each year, most sites will be dry (or rotenoned) to control <br />nonnative fishes to the extent possible. Most sites will also be <br />drainable, so that fishes can be harvested to evaluate results, and so <br />that nonnatives can be prevented from entering the main channel. <br /> <br />In accordance with approved stocking plans, wild and/or hatchery-produced <br />razorbacks will be stocked into the sites for rearing; and wild <br />razorbacks will have access to the site during high flows, through the <br />inlet or over the banks. larval razorbacks will be reared to a size that <br />allows individual tagging (e.g., PIT-tagging), and released into the <br />river (subject to approval by the Recovery Implementation Program). <br /> <br />The Technical Advisory Group recommended the use of wild larvae, because: <br /> <br />1) Theoretically, wild larvae have already imprinted on their <br />natal spawning site, and they will know where to go when they <br />reach maturity; <br />2) Wild larvae are believed to be more fit for survival in the <br />harsh riverine environment than are hatchery-produced fishes; <br />and <br />3) They are believed to genetically represent the existing wild <br />population. <br /> <br />The Genetics Panel, on the other hand, recommended the use of <br />hatchery-produced larvae, because: <br /> <br />1) Hatchery-produced larvae would come from known parentage, with <br />a genetic make-up known to represent the wild population; and <br />2) Wild larvae might be from only a few crosses, and not <br />genetically represent the wild population, resulting in <br />unnatural selection and inbreeding. <br />3) Imprinting and fitness of hatchery-produced larvae were not <br />discussed. <br /> <br />I recommend implementing Objective I with both wild larvae and <br />hatchery-produced larvae, using both floodplain habitats and rearing <br />(hatchery) ponds. The floodplain habitats, connected to the river, <br />would be funded by the Floodplain Habitat Restoration Program. The <br />rearing ponds, not connected to the river, would be funded under the <br />Propagation Element of the Recovery Implementation Program (RIP). <br />New sites will be designed and constructed under each element of the <br />RIP, but with different funding sources. Once the fish are reared <br />to a size where likelihood of survival in the river is improved, <br />they can be PIT-tagged and released. It must be understood, <br />however, that most will never be recaptured. The fact that there <br />are so few razorbacks, that our sampling efficiency in large rivers <br />is so poor, and that razorbacks are less vulnerable to capture than <br />other species, is justification for development of a sound <br />monitoring/evaluation program with refined sampling strategies to <br />evaluate the efficacy of the Floodplain Habitat Restoration Program. <br /> <br />3 <br />