Oyster farming: a new direction for the blue economy

For years, marine sustainability has been portrayed primarily as a battle ‘against’ plastic, industrial discharges and visible pollution. This perspective is no longer sufficient. The sea and coastal waters face endemic and systemic pressures: eutrophication (excess nutrients), warming, loss of biodiversity, invasive species, and the fragility of lagoons and semi-enclosed systems. These phenomena cannot be resolved simply by removing waste: they require ecosystem management and solutions that arise from within the habitat itself. This is where the blue economy can shift the perspective: not merely reducing the impact of economic activities, but generating value by working with the ecosystem. In this context, aquaculture can rightfully form part of the ‘recipe’ for safeguarding our waters.

This is a sector with a twofold benefit: it produces food and value and, under certain conditions, can contribute to water quality. This is confirmed by experts Benedetta Coluccia and Pasquale Sasso, a researcher and lecturer at Pegaso University, who have recently published a study on competitiveness, regional development, productive resilience and alignment with European trends in the Italian oyster industry through the university’s Agrifood Tech & Innovation Observatory: ‘This is active sustainability: oyster farming, in fact, does not merely limit its environmental impact, but can actively contribute to improving water quality through natural processes of filtration and the removal of particulate matter and excess nutrients.’

The two experts, however, emphasise that this effect is neither automatic nor uniform, as it is the result of a combination of various factors: temperature, salinity, the quality of the basin, density and management. Furthermore, with shellfish farming under pressure, partly due to the spread of the blue crab, ‘oyster farming may represent a relatively more resilient diversification strategy’, even though it remains a niche sector: national production stands at around 300 tonnes per year. However, Coluccia and Sasso go on to say, ‘filtration capacity is not merely a biological parameter, but can become a strategic asset’ if translated into verifiable indicators and transparent monitoring. Hence the proposal to establish a collaborative infrastructure for innovation in this sector, because ‘the main bottleneck today is not demand, but the scale of organisation and production’.

This view is shared by Raphaëla le Gouvello, an expert and adviser to the International Union for Conservation of Nature (IUCN) and founder of the NGO RespectOcean, who calls for a change of direction: ‘We must go beyond sustainability and move towards a regenerative blue economy’. The expert explains that, when practised correctly, shellfish farming can help improve the quality of coastal waters (including the removal of nitrogen) and provide habitats for wild species, thereby increasing biodiversity. “These benefits are not sufficiently recognised today,” she explains, emphasising how the lack of access to new sites and increasingly complex regulations are currently creating major challenges for operators.

Le Gouvello reiterates the need for the EU to publish an ambitious roadmap towards a regenerative blue economy, within which the shellfish farming industry could become a key pillar, alongside seaweed cultivation and various types of aquaculture, when combined with the protection and restoration of marine ecosystems and renewable energy. But she warns: “Innovative financial mechanisms will be needed to support entrepreneurship and local initiatives and to reward – including through the mechanism of nature credits (such as nitrogen credits, ed.) – the ecosystem services and benefits that this type of farming provides’.