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IV. GENETICS MANAGEMENT OF WILD STOCKS All presumptive stocks of endangered and candidate fishes must be protected since each may have unique genetic attributes that may be important to their recovery or restoration (Philipp et al. 1986; Rohlf 1991). As species decline to the point where they become listed or candidates, each remaining stock could play an important role in increasing the probability for recovery (Rohlf 1991). The need for management actions such as translocation and establishment of captive populations suggests that recovery/restoration efforts may have been initiated too late for some species (Tear et al. 1993). Natural propagation will be given the first priority in fish recovery/restoration efforts (Figure 1). However, captive propagation of some stocks will be needed. Broodstocks will be developed to produce progeny for reintroduction/augmentation. These fish must have genetic diversity similar to the wild stock. A. Stable Stocks. All naturally sustaining or stable stocks will be managed to prevent irreversible losses of genetic diversity that may result from management interventions or lack of action. Genetic conservation requires the maintenance of similar genetic diversity among wild and captive-reared fish so that the risk of genetic loss or alteration is prevented or minimized (Lichatowich and Watson 1993). A systems approach (See Box 3) incorporating four basic planning steps will be used; (1) scoping and inventory to assess all the issues, problems and potential genetic risks, (2) strategic planning to solve issues, and problems including captive propagation, (3) operational planning to implement strategies, and (4) evaluation. Genetic management opportunities (See Box 2) should be incorporated into recovery strategies. All proposed reintroduction/augmentation activities will be thoroughly evaluated to ensure that they will not disrupt the genetic diversity of remaining wild stocks and to assess their success. Habitat enhancement activities will be implemented before or in conjunction with stocking and will also be conducted as experiments to evaluate the responses of all fish species. These actions are necessary to prevent hybridization or introgression among and within similar species and to minimize competition and predation by nonnative fishes.