Ecosystem-based management to reduce dioxin concentrations in Baltic salmon and herring and the risks to human health: main challenges

Baltic herring and salmon provide a rich source of protein, Omega3 fatty acids and vitamin D for humans, but they also contain high levels of dioxins, which questions their positive health effects. Owing to dioxins, selling Baltic herring and salmon within the EU is restricted, and export outside the EU is difficult. BONUS GOHERR project (Integrated governance of Baltic herring and salmon stocks involving stakeholders) combines biological, public health and social scientific perspectives to explore the potential of ecosystem-based/integrated management of Baltic salmon and herring in reducing dioxins and the related risk to humans. Thus the project contributes to developing the ecosystem-based approach to fisheries management, which requires holistic thinking and comprehensive representations of the ecosystem, including social components. One of the main challenges of the project relates to understanding the system and its functioning, and to analysing how the system could be manipulated. For this, a decision support model is being built that integrates probabilistic information on 1) the predator–prey interaction between salmon and herring and the impact of this on bioaccumulation of dioxins, and 2) the impacts of fish intake on humans, given the dioxin concentrations. The model allowes assessing the effectiveness of alternative fisheries management actions to decrease the dioxin concentration, and the effectiveness of alternative fish-eating recommendations on the consumption of Baltic herring and salmon. The model evaluates the utility of different decision combinations from the perspectives human health, sustainable fishing, ecosystem health, and social effects, in parallel. Another major challenge of the project relates to analysing the role, scale and scope of governance to support the ecosystem-based/integrated management of these fisheries and the dioxin risk, taking into account societal values.