As aquaculture expands to meet the growing demand for seafood, land-based recirculating aquaculture systems (RAS) are increasingly presented as a potentially more sustainable alternative to conventional marine cage farming. These systems offer several environmental advantages, including reduced water consumption, improved biosecurity, and limited interaction with wild fish populations. Nevertheless, several proposed large-scale RAS facilities in Europe and elsewhere have faced substantial public opposition resulting in project delays or cancellation.
This study examined why technologically innovative aquaculture projects with environmental ambitions may nevertheless encounter resistance. Three case studies involving proposed large-scale RAS facilities were compared. Each project generated debate among stakeholders, policymakers, environmental and animal-welfare organisations, and local communities. Information was collected from scientific literature, government reports, public inquiry documents, policy papers, media coverage and other publicly available sources. The caseswere systematically compared to identify the principal concerns raised and the factors influencing project outcomes.
Animal welfare and environmental concerns - including wastewater discharge, energy and water use, and effects on the surrounding environment - featured prominently in all three cases. However, , landscape impacts, local community interests, trust in project developers, transparency, stakeholder engagement and governance also emerged as important sources of opposition. Importantly, the issues that dominated public debate were not necessarily the factors that ultimately caused projects to be delayed or cancelled. Project outcomes were shaped by a broader and interacting set of regulatory, governance, social and economic factors.
These findings demonstrate that technological innovation and environmental performance alone are insufficient to secure acceptance of large-scale land-based aquaculture. Developing and maintaining a social licence to operate also requires credible governance, transparent communication and meaningful stakeholder engagement. The study provides insights that can support the socially responsible development of future land-based aquaculture projects.