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FISH CULTURE-PERSPECTIVE To make significant progress on this issue will require an effective, two-pronged attack. First, scientists must do a better job quantifying the risks and potential benefits of artificial propagation. For example, a typical question to tackle would be, "If hatchery program A were implement- ed, what would be the likely effects (changes in fitness, changes in within- and among-population diversity) on populations B, C, and D, and what would be the short- and long-term consequences of these cbanges for sustain- ability of the resource?" These questions are difficult to answer, but until scientists progress in this area, we cannot provide managers with the information they need to prop- erly evaluate the biological consequences of alternative management actions (Table 1). Second, a framework needs to be developed to help fisheries managers, policy makers, and social scientists evaluate the disparate types of costs and benefits associat- ed with artificial propagation. Again, this will not be sim- ple, but some of the approaches from the field of decision theory could be applied usefully to this issue. Research Major gaps in our understanding occur for most of the key processes associated with fish culture. Some critical issues (e.g., domestication selection, the relative impor- tance of inbreeding depression and outbreeding depres- sion) are regularly identified by scientific workshops and panels as high-priority research topics; however, such re- search is seldom funded because the necessary experiments are expensive, time-consuming (often requiring several fish generations), and logistically difficult. Major new funding initiatives are unlikely in the cur- rent political climate. However, one approach is readily available and could make a significant impact: Devote more hatchery facilities to research. This could involve either setting aside portions of a number of hatcheries or devot- ing one or more facilities entirely to research. Doing so would not only alleviate many logistical problems associ- ated with this type of research, it also would reduce the ex- pense because in most cases retrofitting existing hatcheries to conduct research should be simpler and cheaper than constructing new facilities. On a smaller scale, production programs could incorporate more cooperative research projects at relatively modest cost. Many hatchery man- agers and fish culturists are willing, even eager, to partici- pate in research projects provided they understand the importance of the project and have a stake in its success. Uncertainty More and better research is necessary but is not by itself sufficient. Because new research will not resolve all uncer- tainties, and because in any event some critical information is not likely to be available for many years, it also is essen- tial that we develop workable methods for dealing with uncertainty. For production hatcheries, the most critical questions are, "Given the inevitable uncertainty, where should the burden of proof reside? Should hatcheries be presumed harmless unless proven other~jse (thus risking irreversible losses to biotic integrity if d~leterious effects do occur), or should hatcheries be used only very cautiously (thus risking major sacrifices of societal benefits that may turn out to be unnecessary)?" Underscoring the impor- tance of this issue is the fact that, in many cases, it will be impossible to accommodate all concerns regarding hatch- eries without major changes to existing programs and, in some cases, sacrificing legal mandates to produce fish. For supplementation programs this question has an additional twist: "Should hatcheries be used aggressively in supple- mentation because of their demonstrated ability to pro- duce more fish (thus risking deleterious effects to natural populations that may outweigh the benefits), or should they be used sparingly because of a lack of empiri- cal evidence for long-term benefits to natural populations (thus risking loss of an opportunity to alleviate high short-term risk of extinction or loss of diversity)?" Judicious appli- cation of the precautionary prin- ciple in these situations requires the wisdom of King Solomon. A considerable amount has been written on how to deal with uncertainty in the fields of decision analysis and ecological risk assess- ment (e.g., Raiffa 1968; Lackey 1997), but it has not been used effectively with hatchery issues (see discussion of this issue in Currens and Busack 1995). Two key points are worth men- tioning here. First, both risks and potential benefits should be calcu- lated as a distribution of possible Table 1 shows the type of quantitative analysis necessary to make a direct link between a particular hatchery-wild interaction and the primary and secondary consequences for natural populations. For simplicity, only the modal values (in bold) for stray rate and change in fit- ness are used to evaluate subsequent consequences. For example, this hypothetical hatchery program is most likely to lead to a stray rate between I I % and 20%; jf straying at that level occurs, the most likely consequence is a 6%- I 0% reduction in fitness of the natural popula- tion, and the most likely consequence of a fitness reduction of this magnitude is a 5 I %-100% increase in chance of extinction in 100 years. All values shown are hypothetical. Event Hatchery fish stray into natural populations Magnitudea Probability Consequences Primary Change in fitness Magnitude Probability 0 .05 >+10% .03 1-5% .15 +6 - +10% .07 6-10% .25 -5 - + 5% .20 11-20% .30 -6 - -10% .30 21-40% .20 - I I - -20% .25 >40% .05 < -20% .15 Secondary Change in extinction riskb Magnitude Probability > 1,000% 501 - 1 ,000% 101- 500% 51- 100% 2 I - 50% <20% .05 .10 .25 .35 .20 .05 .Percentage of naturally spawning fish that were reared in a hatchery bChance of extinction in 100 years 20 .. Fisheries Vol. 24, NO.2