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and Westerberg 2002; Allendorf and Leary 1988). This theory has caused concern in the fisheries <br />community because of the apparent loss of genetic variation in some hatchery stocks and the <br />implications of this loss to the augmented population (Waples 1991b). Allendorf and Phelps <br />(1980) suggest this loss may result in a decrease in fitness, such as a loss of alleles that are <br />important in disease resistance. Genetically, the effects of population supplementation with <br />hatchery stocks range from no effect (no survival of stocked fish) to a swamping of the wild <br />genome with hatchery stocks as indicated by marker data (Skaala et al. 1990; Hindar et al.1991). <br />Many authors have modeled potential losses of genetic diversity associated with wild stock <br />augmentation (Laikre and Ryman 1990; Waples 1991 a; Ryman and Laikre 1996); however, the <br />direct relationship between genetic marker diversity and fitness components are rarely addressed <br />and still controversial (Milligan et al. 1994; Waples 1991). Seldom have hatchery stocks been <br />subjected to extensive genetic monitoring as a management, rather than a research tool. We <br />propose to genetically characterize and monitor broodstocks and production fish to prevent the <br />loss of or a change in genetic diversity. <br />Genetic Risks for Broodstock Management and Captive Propagation <br />Founder effects <br />"The fundamental genetic hazard associated with broodstock management within a gene <br />pool maintenance program is loss or undesired changes in the genetic variation or identity of the <br />hatchery population with respect to its donor source" (Williamson 2001). One of the earliest <br />recognized genetic risks of captive rearing on native fish was the potential of a founder effect in <br />the hatchery population. This effect occurs when an inadequate sample of the wild genome is <br />used to develop the captive stock. Typically, this is the result of using too few individuals. Thus, <br />the genetics of future generations do not adequately reflect the donor population. This risk can be <br />minimized by genetic analysis of wild and hatchery stocks to ensure that hatchery stocks contain a <br />24