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minimize inbreeding within the hatchery population of RBS (Blouin et al. 1996; Norris et al. <br />2000). The cutoff for the discrimination of potential pairs will be defined after the initial genetic <br />survey is completed, but is expected to be 0.2. <br />Outbreeding depression, or the loss of coadapted gene complexes, is also of concern <br />within the conservation community. The RBS population in Lake Mohave is predicted to be a <br />sump for inundated populations throughout the basin. If this is true, then outbreeding is an <br />ongoing process occurring in every spawning aggregation. If only distantly similar fish are <br />considered as potential mates, the possibility of outbreeding depression will be exacerbated. <br />Dexter will produce fish for reintroduction that reflect as accurately as possible the genetic <br />identity of the donor populations. The aforementioned activities outline a variety of proximate <br />genetic management safeguards that will promote management success while reducing the risk of <br />genetic hazards inherent in all captive breeding programs (Williamson and Wydoski 1994). We <br />anticipate a dynamic process of identification of selective factors, and adjustments to hatchery <br />protocols to defray the genetic consequence on refugia and production fish. <br />Genetics research needs <br />Inbreeding depression and outbreeding depression are difficult to quantify. However, the <br />importance of both genetic hazards necessitates an effort to quantify the results of our breeding <br />strategy. Staff will initiate a research project to quantify the effects of inbreeding and outbreeding <br />after the initial genetic survey is completed. Staff will produce paired matings of the most and <br />least genetically similar fish with replicates of twenty pairs in each group. Offspring will be <br />reared in identical environments as production fish. Survival and growth will be assessed at 2 <br />months, 6 months, 1 year, and 2 years of age. The` hypothesis will assume that related and <br />divergent matings are not statistically different in growth and survival than production fish <br />30