Ecoviability for ecosystem‐based fisheries management

Abstract

Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.

How do fishing practices influence sperm whale (Physeter macrocephalus) depredation on demersal longline fisheries?

“…To increase profitability, these additional costs should not exceed the benefits gained by minimizing depredation (Trijoulet, 2016;Trijoulet et al, 2018). Further assessments are also be needed to ensure that these operational adaptive measures are in agreement with fisheries regulations and resource management strategies, which is currently one of the key challenges for various stakeholders (Doyen et al, 2017(Doyen et al, , 2012Gourguet et al, 2013;Nielsen et al, 2018). This study has also emphasized the various gaps of knowledge on odontocete depredation.…”

The role of technical protocols and partnership engagement in developing a decision support framework for fisheries management

“…Management, the co-viability approach can also provide an interesting perspective to provide advice 675 reconciling ecological, economic and social dimensions (see Doyen et al, 2017 andGourguet et al, 676 2013). Stakeholder and manager engagement in this kind of approach are currently under study.…”

From Resistance to Transformation: A Generic Metric of Resilience Through Viability

“…First and foremost, resilience is about dynamic systems, including the possible existence of feedbacks, nonlinear trajectories, and thresholds. This sustainable zone is the multidimensional space within which the system is viable, that is, does not violate its viability constraints today and in the future (Baumgärtner & Quaas, 2009;Cissé et al, 2013;Doyen et al, 2017;Doyen & Martinet, 2012;Mouysset et al, 2013;Schuhbauer & Sumaila, 2016). Derived from control theory (Bellman, 1964), the aim of viability approach is to analyze the compatibility between the (possibly uncertain) dynamics of a system and a series of constraints and to determine a set of controls, actions, or decisions that would allow the system to stay within the "sustainable zone" defined by the limits of the various constraints.…”

“…Derived from control theory (Bellman, 1964), the aim of viability approach is to analyze the compatibility between the (possibly uncertain) dynamics of a system and a series of constraints and to determine a set of controls, actions, or decisions that would allow the system to stay within the "sustainable zone" defined by the limits of the various constraints. This sustainable zone is the multidimensional space within which the system is viable, that is, does not violate its viability constraints today and in the future (Baumgärtner & Quaas, 2009;Cissé et al, 2013;Doyen et al, 2017;Doyen & Martinet, 2012;Mouysset et al, 2013;Schuhbauer & Sumaila, 2016). In mathematical terms, this sustainable zone is called the "viability kernel.…”