Stakeholder Perspectives on Blue Mussel Farming to Mitigate Baltic Sea Eutrophication

Abstract

Here, we present an application of systems thinking to controlling Baltic Sea eutrophication—a wicked environmental problem characterized by multiple stakeholder perspectives and no single, agreed upon solution. The Baltic Sea is one of the most polluted waterbodies in the world. More than 40 years of land-based (linear) measures have failed to adequately control eutrophication, yet internal (circular) measures are rarely used. Farming native blue mussels for nutrient capture has been proposed as one measure for eutrophication control, but the relevant stakeholders disagree as to its environmental, social and economic benefits. Here, we present the views of four Swedish stakeholder groups—academics, entrepreneurs, municipal government employees and representatives of non-governmental organizations (NGOs)—on the sustainability of native blue mussel farming, a circular measure for eutrophication control. Using semi-structured interviews, we elicited stakeholder perspectives on the environmental, economic and social dimensions of blue mussel farming. The interviewees generally agreed that blue mussel farming is not currently economically sustainable, but that it can contribute to the social sustainability of coastal regions. Academics were skeptical of the environmental benefits, claiming that farms could reinforce eutrophication, whereas the remaining stakeholder groups argued for its potential to mitigate eutrophication. In a roundtable discussion conducted one year after the original interviews, all stakeholder groups agreed that blue mussel farming alone will not fix Baltic Sea eutrophication, but can be part of the solution together with land-based measures. All groups also agreed on the need for cautious upscaling, continuous environmental monitoring and constant improvement if blue mussel farms are to be part of a “toolkit” for eutrophication control. Our results highlight the fact that wicked environmental problems can be addressed when multiple stakeholder groups with differing perspectives have the opportunity to achieve consensus through dialog.

Towards environmentally friendly finfish farming: A potential for mussel farms to compensate fish farm effluents

“…Nevertheless, it is practically impossible to directly capture the N released due to finfish excretion; mussel farming provides a promising internal measure to mitigate these emissions (Petersen et al, 2016;Žilinskaitė et al, 2021).…”

“…When using feed pellets in which P is bound in hydroxyapatite, emissions do not easily enter into the nutrient cycle and mussel farming in combination with fish farming can actually remove legacy P from the marine ecosystem. Nevertheless, it is practically impossible to directly capture the N released due to finfish excretion; mussel farming provides a promising internal measure to mitigate these emissions (Petersen et al, 2016; Žilinskaitė et al, 2021).…”

“…This largely explains why the south‐west region of the study appeared as the most promising area for nutrient mitigation by mussels. Nevertheless, these limiting factors do not prevent the successful farming of mussels in the Baltic Sea region, as farming solutions are still being optimized (Žilinskaitė et al, 2021). Importantly, the appropriate site selection for the co‐farming of mussel and finfish can result in reducing both expenses and impacts.…”

“…Moreover, the relatively high biomass yields at mussel farms in the south‐west region should ensure the economic feasibility of these farms beyond the compensation bargain. Currently, blue mussel farming is considered economically unsustainable in the Baltic Sea (Žilinskaitė et al, 2021), due mostly to the low number of mussel farms in the region. Once a sufficient and reliable quantity of mussel biomass is produced, greater incomes can be expected.…”