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with Service technology centers, field stations, tribes, and other states and federal agencies. • Captive broodstocks serve as an "insurance policy" if the wild stocks become extirpated and provide fish for experimental studies that are part of the restoration or recovery efforts. Planned captive propagation should minimizes the production of excess fish. In the absence of natural reproduction and restoration of natural spawning habitats, a genetic preservation program must be initiated that includes a culture program. Starting this recovery activity before the wild population has been reduced to a low number of individuals increases its chances of success and minimizes the likelihood of extinction (IUCN 1987). This strategy provides time to solve husbandry problems, increases the probability that adequate wild fish can be removed to give the new captive population a secures genetic and demographic foundation, and minimizes adverse effects of removing individuals on the wild population (Ralls and Ballou 1992). Captive populations should be managed to maximize genetic diversity and heterozygosity to counter unwanted genetic changes in captivity due to selection (Frankham et al. 1986) and avoid possible deleterious effects of inbreeding (Ralls et al. 1988). Without genetic variation, the captive individuals or their reintroduced progeny would be unable to adapt to future environmental changes (Frankel and Soule 1981) and various management strategies, such as within-family selection against recessive lethal or serious pathologies (Foose et al. 1986). The captive individuals must be housed (refugia) in such a way that the parentage of all offspring is known with certainty, and detailed records on all individuals born in captivity must be recorded. Refuges serve a vital function in • maintaining and protecting the genetic integrity of the species. A captive breeding and rearing program should be designed and conducted to reduce the risks of drift, selection, and inbreeding; and the hatchery stock should be founded with a sufficient number of individuals to accurately reflect the genetic composition of the natural population from which it was derived. Genetic profiles of each wild population need to be developed and minimum effective population sizes estimated and set as a goal. Based on these data, a certain number of wild brood fish are randomly captured and marked (tagged) from a designated population in association with spawning. Non-lethally sampled tissues must be taken from each wild fish for genetic identification and characterization. The number of wild fish removed at any one time must not adversely impact the genetic character and productivity of the donor population (Williamson 1992). In association with the captive broodstock management program, genetic risk assessment should be accomplished to make sure activities conducted do not impose an undo genetic burden upon the population and that genetic conservation be practiced for all fish stocks. Genetic risk assessment has identified four types of genetic risk: 1) extinction, 2) loss of within population variability (genetic drift and founder effect), 3) loss of between-population variability, and 4) domestication selection. Genetic Management Guidelines For Listed And Candidate Fish Species In Region 6 provides a conceptual framework for genetics management and rationale for maintaining genetic diversity of wild and captive listed and candidate fish species. Every aspect of the controlled •