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FISH CULTURE-PERSPECTIVE has a strong research and evaluation component. In spite of these efforts, data for the early 1990s showed that, com- pared to natural adults, returning hatchery fish were younger, were smaller for the same age, and had lower fecundity for the same size (Bugert et al. 1992). The under- lying causes of these somewhat surprising phenotypic changes are not known; however, even if the changes were entirely an environmental response to hatchery conditions, they still would represent a significant single-generation reduction in productivity of the population. · Reisenbichler (1997) has compiled available informa- tion regarding the effects of hatchery culture on fitness of anadromous Pacific salmonids in the wild. These data-all from controlled experimental studies-are imperfect: They apply to a single species (steelhead) and in some cases confound the effects of fish culture and stock transfers. Nevertheless, they are the best available data on this issue, and they demonstrate that fitness of hatchery-reared fish in the wild can be substantially reduced compared with natural fish. Furthermore, the reductions in fitness occurred across all life stages and increased with the num- ber of generations of fish culture. These examples are important but not entirely satisfy- ing; they raise as many questions as they answer. Never- theless, they emphasize a point made by Busack and Cur- rens (1995:77) regarding effects of hatchery fish on natural populations: "We are unaware of rigorous research designed to detect genetic impacts that has failed to find them." What is lacking is a consensus on what constitutes a reasonable approach to this issue given the substantial uncertainty involved and the potentially major conse- quences of whatever actions are (or are not) taken. Myth 5: It is not a hatchery problem; it is a fisheries management problem. Campton (1995) and others (e.g., Rense11997) have argued that critics of hatcheries often confound biological factors intrinsic to hatcheries with effects of fisheries man- agement (stock transfers, selective breeding, extensive har- vest rates in mixed-stock fisheries). As a result, many hatchery managers believe they have "become scapegoats for virtually every perceived negative biological effect associ- ated with the artificial propagation, release, and management of anadromous salmonid fish" (Campton 1995:338). This argument has some merit. Adaptive management is most effective when the consequences of individual actions can be evaluated and modified as appropriate. To the extent that distinguishing between biological and management fac- tors facilitates this process, it can be useful and productive. However, we should be careful not to exaggerate the dichotomy between biology and management. No fish hatchery exists in a vacuum isolated from fisheries man- agement concerns; rather, every hatchery program is designed to meet one or more management objectives (e.g., harvest enhancement, mitigation, conservation). Some factors identified by Campton such as stock trans- fers and mixed-stock fisheries are primarily a function of fisheries management rather than fish culture, but many 18 . Fisheries others involve both. For example, selective breeding, when it occurs, is carried out by fish culturists to achieve a fish- eries management objective. The effects on natural popula- tions from an action such as selective breeding are the same whether one chooses to allocate this action to fish culture or fisheries management. In this case, the only meaningful unit to consider is the overall hatchery pro- gram, which encompasses both fish culture and fisheries management. Put another way, "Fish culture is as much a part of management as management is of fish culture" (Incerpi 1996). It is unfortunate if hatchery managers and fish cultur- ists believe they are scapegoats in the controversies about hatcheries. The concerns about hatcheries I have raised here and elsewhere are not directed at those involved in the culture of fish-professionals conscientiously trying to do their job the best way they know how-but rather toward the effects of hatchery programs on natural fish populations. To the extent that we can depersonalize the debate about hatcheries and redirect energy to solving the problems rather than trying to assess blame, the resource as a whole will benefit. Myth 6: Everything will be okay if we have a good monitoring program. Although no one doubts the importance of monitoring and evaluation (M&E) for adaptive management, there is a very real danger in relying too heavily on M&E as a sub- stitute for meaningful and comprehensive risk manage- ment. The danger arises from three factors. First, M&E for hatchery programs has limitations with respect to both reliability and timeliness. Statistical power to detect genetic effects of hatcheries can be relatively high for selectively neutral molecular markers, which can pro- vide key information on gene flow between hatchery and natural populations, individual reproductive success, and effective population size (e.g., Waples et al. 1993). Howev- er, the most serious concerns regarding fish hatcheries in- volve fitness effects on phenotypic, behavioral, and life history traits in natural populations. As discussed by Hard (1995; see also Peterman 1990), the power of even the most ambitious M&E program to statistically detect a fish cul- ture effect on traits such as these is likely to be very low because the background noise level (natural variability in the same traits) is typically very high. Furthermore, even if such an effect is detected, it will generally occur only after several (fish) generations of monitoring. This means that artificial propagation could substantially harm natural populations long before there is any reasonable expectation of being able to detect it. Of course, this does not mean that deleterious effects will always occur; however, it should give pause to those willing to embark on a high-risk pro- gram in the expectation that they will be able to quickly and surgically intervene at the first sign of an undesirable outcome. Unfortunately, in most cases that is a myth. Second, even if harm is found, there is no guarantee that effective remedial action will be taken. To be effective, an adaptive management program should include a Vol. 24, No.2