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hybridization (Maddux et through routine sampling levels of hybridization. al. 1993). Wild fish stocks will be monitored and necessary actions taken to avoid unnatural V. GENETICS MANAGEMENT OF CAPTIVE STOCKS A. Determining the Need for Captive Propagation and Reintroduction Captive propagation may be necessary if a fish stock does not have sufficient recruitment to achieve or maintain a self-sustaining population. Stocks may require captive propagation to produce fish for research and for approved augmentation or restoration programs (Williams et al. 1988). Captive-reared fish can be used for (1) genetic refugia and broodstock development, (2) research and development, (3) information and education, and (4) augmentation or restoration (Wydoski 1994). Refuges serve a vital function in maintaining fish that may become extinct due to declines in wild populations, catastrophic risks, and broodstock development. Captive-reared fish are needed for research to conduct laboratory and field experiments related to ecological requirements, habitat use, interactions with nonnative fishes, response to contaminants, olfaction and chemoreception studies, fish passage, taxonomy, anatomy, physiology, performance, fitness. and hereditary trials. Fish specimens are also needed for use in public relations programs and to educate the public. Augmentation may be required to provide a "jump-start" mechanism to supplement fish in habitats where the wild populations are very depressed. Restoration stocking may be necessary in river reaches where stocks have been extirpated. B. Genetic Risks Associated with Captive Propagation and Reintroduction. Planning recovery/restoration efforts for endangered and candidate fishes will be accomplished following a logical and systematic approach that will minimize potential genetic risks(See Box 3). A genetic risk is broadly defined as the sum of critical uncertainties associated with any management action or inaction that may change the genetic diversity both within and among wild stocks. Risk assessment consists of (1) estimating risk, and (2) managing risk (Lichatowich and Watson 1993). Major genetic risks associated with captive propagation can be identified and reduced through a careful assessment. Risk assessment will be addressed in each specific reintroduction or augmentation plan. The potential to manage genetic risks to wild stocks will be essential for a "no jeopardy opinion" under Section 7 consultation of the Endangered Species Act. If conducted in a scientifically sound manner, captive propagation will prevent: (1) extinction of the species: (2) loss of genetic diversity within a species, stock, or population: (3) loss of genetic diversity among stocks or populations; and (4) inadvertent artificial selection that may lead to directional succession from inbreeding or genetic swamping of wild stocks (Busack 1990; Kapuscinski et al. 1993). The genetic processes that 14