Introduction
Blue mussel farming is a form of non-fed aquaculture with high potential for more sustainable protein production, offering diverse ecosystem services while generally requiring fewer emissions and resources than fed aquaculture, such as salmon and other finfish (van der Schatte Olivier et al., 2020). There is growing interest in expanding this sector in response to calls for a transition towards sustainable and climate-smart protein to improve the health of the planet and people (Blanchard et al., 2017). Despite this potential, the global blue mussel aquaculture industry has remained relatively stagnant in recent decades (FAO, 2009). The potential for the expansion of the sector is currently influenced by supply chain efficiency (Krause et al., 2025; Avdelas et al., 2021), environmental conditions (Steeves & Filgueira, 2019; Padin et al., 2024), social acceptance (Wood & Filgueira, 2022), regulation (Fox et al., 2020), and economic conditions (Avdelas et al., 2021). These drivers generate uncertainties that hinder the industry's ability to plan for expansion by making it difficult to anticipate potential challenges and risks, and to identify where expansion opportunities may exist. Many drivers of mussel aquaculture are related to socio-economic and cultural contexts that vary geographically. Therefore, the expansion of mussel aquaculture will require coordinated yet place-specific strategic management to account for the many complex and interconnected external factors influencing the success of the sector. This study aims to identify the most relevant opportunities and barriers to the expansion of blue mussel aquaculture using semi-structured interviews with 18 stakeholders across 12 producer countries in the North Atlantic. This aim is addressed through a qualitative investigation and coding analysis using NVivo guided by the PESTEL (political, economic, social, technological, environmental, and legal) framework.
Results
Results revealed a greater number of barriers than opportunities across all PESTEL categories. Opportunities were identified but were often described as contingent on improvements in policy support, access to technology, and market development. Across all categories, findings highlight that mussel aquaculture is not constrained by a single limiting factor, but rather by interconnected structural challenges. Social factors emerged as the most prominent influence overall, particularly in relation to consumer demand and public acceptance, followed by environmental and economic factors. Technological factors were the only category more frequently associated with opportunities than barriers. Technology was also the least prominent category for barriers, suggesting that innovation may play a key enabling role. Legal factors related to government regulations were least frequently associated with opportunities, indicating an area where governments and policymakers could provide stronger support if expansion were a priority.
Discussion
This study offers fresh perspectives on the opportunities and barriers to blue mussel aquaculture expansion in the North Atlantic. Previous research has recognized key barriers, including low profitability, labour shortages, limited seed availability, environmental uncertainty, trade disruptions, low consumer demand, and complex licensing systems (Krause et al., 2025; Fox et al., 2020). Further, the participants in this study noted that climate change, restricted access to finance and technology, competition for marine space, and fragmented governance often affect small-scale producers most severely. Key opportunities recognized by the literature included sustainability, ecosystem services, contributions to food security, and rural employment (Avdelas et al., 2021; Bianchi et al., 2022). Participants also highlighted market opportunities through ecolabelling, tourism, geo-cultural branding, and product innovation, as well as technological advances in offshore farming, hatcheries, monitoring systems, and smart farming systems. Findings also showed apparent regional differences; for example, seed shortages were major concerns in some European countries but appeared less significant among participants from North America and Scandinavia.
Overall, the study suggests that successful expansion will require place-based strategies, streamlined regulation, market development, innovation, and coordinated policy that recognizes the role of mussel aquaculture in sustainable food systems, coastal economies, and environmental management.
Acknowledgments
This work is part of the Mussel Puzzle project and is led and funded by the Research Institutes of Sweden (RISE).
References
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