and the Future of Wild Fish Populations

Abstract

We explored the social and ecological outcomes associated with emergence of a management panacea designed to govern a sto- chastic renewable natural resource. To that end, we constructed a model of a coupled social-ecological system of recreational fisheries in which a manager supports naturally fluctuating stocks by stock- ing fish in response to harvest-driven satisfaction of resource users. The realistic assumption of users remembering past harvest expe- riences when exploiting a stochastically fluctuating fish population facilitates the emergence of a stocking-based management pana- cea over time. The social benefits of panacea formation involve dampening natural population fluctuations and generating stability of user satisfaction. It also maintains the resource but promotes the eventual replacement of wild fish by hatchery-descended fish. Our analyses show this outcome is particularly likely when hatchery- descended fish are reasonably fit (e.g., characterized by similar survival relative to wild fish) and/or when natural recruitment of thewildpopulationis low(e.g., attributable tohabitatdeterioration), which leaves the wild population with little buffer against competi- tion by stocked fish. The potential for release-based panacea for- mation is particularly likely under user-based management regimes and should be common in a range of social-ecological systems (e.g., fisheries, forestry), whenever user groups are entitled to engage in releaseor replanting strategies. Thenet result willbe thepreservation of a renewable resource through user-based incentives, but the once natural populations are likely to be altered and to host nonnative genotypes. This risks other ecosystem services and the future of wild populations.