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~ <br /> : <br />' t <br /> <br /> naturally. Once progeny have reached suitable size for release, they will be <br /> marked and released to the adjacent mainstem adult population. The amount of <br />' genetic variability conserved by this technique is limited by the number of <br /> breeding adults, which in turn is limited by the acreage of available habitat. The <br /> same adults should not be used repeatedly for this purpose. <br /> 3. Utilize hatchery propagation based on a broodstock. Broodstock used in <br />' hatchery propagation should include the maximum number of wild fish possible. <br /> Strict breeding pedigrees should be followed to minimize inbreeding and at the <br /> same time pass on a maximum diversity of alleles to F2 progeny. Genetic <br /> variability passed on from agiven-sized broodstock is governed by: <br /> a. measured contributions of gametes from individuals with known genetic <br /> attributes; or <br />' b. a statistical breeding regime based on the probabilities that each allele <br /> present in the broodstock is present in their progeny. <br />' 4. Use wild adults from Lake Mohave as broodstock. Once spawned, each. wild <br /> adult would be PIT tagged and returned to Lake Mohave, using each adult only <br /> <br />t once. <br /> Of these strategies, the first one is preferred as it maintains the highest genetic <br /> variability in these fish by potentially using the maximum number of wild fish. <br />' Regardless of the mating strategy applied, the only genetic variation that can be <br /> passed on to the progeny in a hatchery setting is that of the original broodstock <br /> (Minckiey et al. 2003). If the complete component of genetic variance is not <br />' captured in the broodstock, genetic variation will be diminished and less new <br /> variation generated. The potential for reduced fitness due to fixation of <br /> detrimental alleles may be increased. Such reductions in fitness when the <br />' number of contributing individuals declines appear to be a particularly severe <br /> problem in species with large ancestral populations and consequently high <br /> historical genetic loads (Hedrick and Kalinowski 2000). Management to maintain <br />genetic variance should be under the most natural conditions possible, <br /> emphasizing achievement and maintenance of the species' carrying capacities in <br /> <br />' diverse habitats. The end result should be increasing opportunities for <br />emergence of novel variation <br />thus maximizing adaptive potentials <br /> . <br />, <br /> CONDITIONING METHODS <br /> <br />12 <br /> <br />