Social-ecological interactions, management panaceas, 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 stochastic 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 stocking fish in response to harvest-driven satisfaction of resource users. The realistic assumption of users remembering past harvest experiences when exploiting a stochastically fluctuating fish population facilitates the emergence of a stocking-based management panacea 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 hatcherydescended fish are reasonably fit (e.g., characterized by similar survival relative to wild fish) and/or when natural recruitment of the wild population is low (e.g., attributable to habitat deterioration), which leaves the wild population with little buffer against competition by stocked fish. The potential for release-based panacea formation 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 release or replanting strategies. The net result will be the preservation 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.stocking panacea | wild population collapse | angler satisfaction | social-ecological model | cultural ecosystem service

A review of on-ground recovery actions for threatened freshwater fish in Australia

“…The low incidence of reported success for water management should be viewed with caution because only six actions reported on monitoring. The lower incidence of monitoring associated with stock enhancement may reflect the view that stocking is a panacea and an assumption that simply reintroducing individuals 'solves the problem' (Harris 2003;van Poorten et al 2011). Monitoring is a critical component of threatened-species recovery, because the response of the focal species to management interventions is often difficult to predict with any certainty.…”

“…Stock enhancement continues to grow as a favoured solution for maintaining and/or enhancing fish populations as a result of its perceived simplicity (Philippart 1995;Molony et al 2003) and its perceived role as a panacea that 'solves the problem' (Harris 2003;van Poorten et al 2011). Ideally, stock enhancement should be a short-term response, applied after the underlying reasons for a species decline have been removed or reduced (Cowx 2002).…”

Challenges in Using Hydrology and Water Quality Models for Assessing Freshwater Ecosystem Services: A Review

“…In the literature on freshwater ecosystem services modelling, many studies have focused on fish populations: for example Boughton and Pike [52] studied the impacts of altered storm patterns on fish migration windows, Bouska, et al [53] studied the impact of environmental changes on fish species distributions, Downing, et al [54] focused on the effect of lake management on the stock of fish, Nelson, et al [55] studied the impact of sediments, water flows and temperature on fish assemblages, and van Poorten, et al [56] studied the effects of stocking management on the fish population. However, the fish dynamics depend mainly on the availability of food.…”

“…They can be shaped as probabilistic models such as Bayesian Belief Networks [33,59] where the links between variables can be characterised with expert knowledge or from datasets. They can also be deterministic models where the links are characteristics by empirical equations from the literature [55,56]. More qualitative approaches can also be used, such as feedback diagrams where only the positive or negative character of the relationships between variables is expressed [54].…”

Hydropower vs. fisheries conservation: a test of institutional design principles for common-pool resource management in the lower Mekong basin social-ecological system

“…We aim to contribute to that body of literature by adopting a socialecological systems approach, characterized by an ultimate interest in understanding social-ecological outcomes and trade-offs, i.e., not just cooperation (Ostrom 2009, van Poorten et al 2011, Epstein et al 2013, Evans et al 2014, Fleischman et al 2014b). …”