What’s happening?

“Blue” foods including shellfish, fish and algae carry significant potential to improve global development if the appropriate policies and investments are adopted, according to a major global review. Professor Dave Little of the University of Stirling’s Institute of Aquaculture contributed to the Blue Food Assessment research, with five peer-reviewed papers produced as part of the project. He said small fisheries and aquaculture provide 90% of jobs in the sector and have a crucial role to play in local food security. The review examined how aquaculture can improve diet, protect livelihoods and reduce the environmental footprint of the food industry.

Why does this matter? At present, over 2,500 species and groups of shellfish, fish, aquatic plants and algae are either fished or cultivated as part of global food networks. Given global demand for blue foods is expected to double by 2050, fisheries and aquaculture have a large role to play in the sustainability and resilience of these systems.

Blue foods can play a significant role in delivering more sustainable diets globally. One of the five published studies explored the environmental performance of blue foods, with researchers finding major species produced in aquaculture such as carp and salmon have a lower footprint in comparison to chicken, which is considered the most efficient land-based livestock species. On average, most blue food stocks produced for human consumption generate fewer greenhouse gases, water pollution and require less resources than livestock.

Among aquatic foods, farmed seaweeds, bivalves and small pelagic species including sardines generate the least greenhouse gas emissions, according to researchers. In addition, aquaculture farms for species such as oysters and mussels can simultaneously offer natural benefits, such as filtering excess nutrients from water and removing pollutants to improve water quality.

In another study, researchers evaluated the role of small-scale fisheries and aquaculture operations, which provide livelihoods for over 100 million people around the world and ultimately sustain one billion but are often overlooked in policy and decision-making. It highlighted that local seafood producers are more likely to survive shocks, such as the Covid-19 pandemic during which smaller actors were able to fill market gaps as larger producers scaled back international operations.

Despite some efforts from governments and organisations, including a fast-track plan for small fishing co-operatives in South Africa, and a framework aiming to enhance sustainability in Southeast Asian small-scale shrimp farms, the progress of small aquaculture operations is still hindered by disproportionate inaccessibility to resources, climate change risk and social exclusion. The analysis noted women as crucial actors in ensuring an equitable food sector, highlighting the gender inequalities that continue to undervalue them.

It’s worth also noting that while blue food systems can help improve global development with the right support, their benefits are climate-vulnerable. For instance, ocean-based aquaculture operations may be impacted by ocean acidification and changing species distributions, while land-based fisheries could see knock-on effects from regional droughts posing risks to freshwater supplies. It’s worth noting aquatic food systems in developing nations such as Africa, the Indo-Pacific and Southeast Asia are the most exposed to climate risks and food security.

It is important techniques are employed that take account of this and also minimise the environmental impacts of aquaculture. To curb water pollution, tech-based offerings are gaining interest, such as nanobubbletechnology by Moleaer that restores the health of aquatic systems and water quality in salmon aquaculture. Researchers are also working on solutions to reduce waste at source, for instance by developing biodegradable rope that can be composted, as well as creating less-polluting fish feed formulas.

Projects to repurpose aquaculture waste are also underway, with scientists at Hanoi University finding applications in biofuels, and in Singapore for biomaterials for bone repair. Some industry experts have also suggested bolstering fish populations could be used as a natural climate mitigation measure to remove large quantities of atmospheric CO2 in a similar fashion to land-based forest ecosystems. Finally, organisations are working alongside Indigenous communities – which possess often overlooked traditional and cultural knowledge – to minimise the environmental impact of fisheries by utilising low-impact techniques such as hook and line.

Source: University of Stirling