When it comes to food, the world faces a tangle of seemingly impossible choices: Increase agricultural land-use to address food insecurity and you drive deforestation and risk biodiversity collapse. Industrialize meat production to bring prices down and you set the stage for new pandemics and imperil the welfare of billions of farmed animals. Feeding the world’s growing population without worsening parallel catastrophes has become the defining challenge of the 21st century. One could be forgiven for attempting to conjure a portal to a future that would avoid tradeoffs entirely.
And some, it seems, have attempted to cast just such a spell: “Blue foods” is the way to save the world.
Blue foods—food like fish, shellfish, and seaweeds obtained from bodies of water—and farmed blue foods in particular have been promoted by researchers, industry, NGOs, and the World Economic Forum alike as the way to feed the world; as a solution to hidden hunger and malnutrition; as the path to achieving global food system transformation; and as the fix for multiple global challenges. A common refrain in these circles: “The future of food is not just green—it’s blue.”
But as researchers studying aquatic organisms, their ecosystems, and their welfare, we are compelled to say: not so fast. And not like this.
Blue foods do have benefits, and they certainly have a role to play. For example, as a source of protein, farmed shellfish have a smaller carbon footprint compared to beef. And seaweed farming may increase carbon sequestration, ameliorate ocean acidification, and lead to socioeconomic gains. But the details matter, and so does the scale.
Mariculture dewilding can impact the environment, wildlife, captive animals, and humans’ view of each. (Credit: Emma Bautista)
For most of human history, the world’s oceans have been largely free of intensive farming. There have been myriad overfishing crises, but cultivation of the oceans has been limited. That may soon change.
Marine and coastal aquaculture production has soared since 1990, reaching a record 78.4 million tons in 2022. This expansion includes the growth of resource-intensive industries like salmon farming. It also includes attempts to rapidly domesticate hundreds of species. Such attempts have accelerated in recent decades, subjecting countless wild animals to captive conditions that are incompatible with their welfare. And yet, production is projected to increase for all major farmed species in the next decade.
In short, the rise of “mariculture”—farming in the ocean—is poised to dramatically alter our marine footprint. But, as we write in a new paper published last week in the journal Science Advances, the full suite of risks from mariculture are incompletely mapped.
