A blue revolution is currently underway in response to growing food insecurity, as aquaculture is playing an increasingly important role in sourcing food around the world. However, despite providing a livelihood for billions of people, policies surrounding the sustainability of blue foods and the viability of a blue economy remains unclear.
The future of aquaculture. New fish farming technologies
The need for new food drives the blue food revolution
Food insecurity is increasing due to climate variability, human conflict, and economic instability. In conjunction with the rise of greenhouse gas emissions, the loss of biodiversity, and the degradation of food systems, a growing portion of the human population is facing malnutrition. In response, food policies have shifted their focus to alternative food production methods, including blue foods harvested from aquaculture.
Aquaculture, which refers to the farming of 'blue foods,' including aquatic animals and seaweeds, is the fastest-growing food production sector in the world. With a growth rate of 5.8% annually over the last two decades, aquaculture is becoming increasingly important for human development, well-being, and long-term food security. In 2016, the global production of aquaculture reached 80 million tons of food, and the amount and diversity of food types continue to increase.
Around the world, blue foods supply protein to over 3.2 billion people and support the livelihoods of over 800 million people, the majority of which are small-scale, local, community-based systems. However, despite their growing contributions and future potential, blue foods tend to be underrepresented in discussions about how to feed the world's population over the coming decades sustainably.
Many issues persist in understanding the factors underlying the supply and demand of blue foods. Specifically, the regional and species-specific aspects of demand are often obscured. This was further discussed in a 2021 study by Naylor et al., who analyzed the roles of economic, demographic, and geographic factors and preferences in shaping blue food demand.
The study used data from the FAO and The World Bank, published models, and case studies, to demonstrate distinct geographic patterns in the demand and supply of aquacultural foods. Findings showed strong regional patterns based on culture, food availability, and socioeconomic parameters. For example, results showed high consumption of freshwater fish in China and pelagic fish in Ghana and Peru, where these fish are widely available, affordable, and traditionally eaten.
The study concludes by projecting a doubling of the demand for fish by 2050, and the authors highlight that the rising demand's nutritional and environmental consequences will depend on substitution among fish groups and other animal source foods in national diets.
Contribution to food security and prospects of a blue economy
According to a 2014 study by Waite et al., as of 2010, the production of blue foods occupied nearly 20 million hectares of land, of which 70% was inland, and 32% was coastal. These activities focus on tropical and subtropical regions, with Asia accounting for nearly 90% of global aquaculture production in 2016. By 2018, the counties ranked highest in aquacultural food production were China (61.5% global production), followed by India, Indonesia, Vietnam, and Bangladesh.
Blue foods also encompass a range of species. Nearly 600 species are used for aquaculture, and this number keeps increasing. The species of highest value are carp, catfish, tilapia, salmon, and shrimp, which can be used for human consumption and as animal feed.
As aquacultural activities expand to new areas, use new species, and use new technologies, strategies are beginning to integrate knowledge from different areas. For instance, deep coastal food webs are increasingly exploited for their rich fish communities that have remained less affected by fishing due to technological constraints. Deep sea dredging has recently allowed these areas to be fished.
However, a study by Queiros et al. in 2019 presents how the exploitation of deep coastal areas may compromise carbon fluxes as these areas play a key role in CO2 sequestration. This is of ecological concern as climate change mitigation is at the foreground of current environmental policy development. In response, the authors highlight that such areas should be a priority for policies aiming to preserve or limit exploitation, yet policymakers' decisions remain unclear.
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Blue frontiers- limitations and challenges to the blue revolution
The rapid development of aquaculture has been considered the blue revolution. Although human demand for food may be addressed by relying on aquaculture, the blue revolution of aquaculture is associated with a wide range of ecological concerns.
This was reviewed in a 2019 study by Ahmed and Thomason. The study presented how aquaculture generates a range of environmental concerns, including habitat destruction, water pollution, eutrophication, biotic depletion, ecological impacts, and disease outbreaks. These act on short-term timescales, yet other impacts also act in the longer term, including increased carbon emissions associated with mangrove deforestation due to shrimp cultivation.
Authors emphasize that to increase fish production for a growing global population, aquaculture must grow sustainably while, at the same time, its environmental impacts must reduce significantly. The study concludes that to fulfill the blue growth potential, policies must address environmental concerns in parallel to increasing food production.
This conclusion was echoed in other studies, including a 2021 study by Farmey et al., who further explored the competing uses of ocean resources in the race to set up a blue economy. The authors also discuss how the emphasis of the blue revolution is currently on production growth rather than the equitable distribution of benefits or sustainability. As a result, this has created flawed assumptions in our conceptual view of a blue economy.
The equitable distribution of resources and long-term viability of production are key elements to consider in the production of blue foods. In turn, considering such elements would allow blue foods to contribute towards the Sustainable Development Goals to a greater extent, including the objectives to reduce hunger and malnutrition.
- Ahmed, N., & Thompson, S. (2019). The blue dimensions of aquaculture: A global synthesis. Science of The Total Environment, 652, 851–861. https://doi.org/10.1016/j.scitotenv.2018.10.163
- Blue food. (2021, September 15). Nature. https://www.nature.com/immersive/d42859-021-00055-6/index.html?error=cookies_not_supported&code=ccded1cd-8f08-4aec-8030-aac32fa78358
- Naylor, R. L., Kishore, A., Sumaila, U. R., Issifu, I., et al. (2021). Blue food demand across geographic and temporal scales. Nature Communications, 12(1). https://doi.org/10.1038/s41467-021-25516-4
- Queirós, A. M., Stephens, N., Widdicombe, S. et al. (2019). Connected macroalgal‐sediment systems: blue carbon and food webs in the deep coastal ocean. Ecological Monographs, 89(3). https://doi.org/10.1002/ecm.1366