Aquaculture is often framed as a vital solution to food security by expanding the supply of seafood for a growing population. But new research from the University of British Columbia suggests the industry may be heading in the wrong direction.

Today, most farmed seafood comes from fin fish — like salmon, trout and tilapia — as well as shrimp. However, farming these species delivers limited benefits for food security, climate mitigation and biodiversity, according to the paper published in the journal Fish and Fisheries. Aquaculture is linked to water pollution, disease outbreaks and farmed fish escaping and mixing with wild populations. It also depends on fishmeal and fish oil, the production of which requires fossil fuels and depletes small fish that other marine species rely on.

“While aquaculture used to focus mostly on nutritious species low on the food chain (like carps, mussels and seaweeds), we now farm lots of resource-intensive fish species that are tough on the environment,” Aleah Wong, a PhD candidate at University of British Columbia and the lead author of the study, tells Sentient in an email.

One way forward, the study suggests, is expanding the production of bivalve species — like mussels and oysters — and seaweed. These species don’t require fish-based feed and can provide a range of environmental benefits, Wong writes.

However, bivalves and seaweed remain underproduced globally and scaling them up is “very tricky and requires policy, market and cultural shifts,” Wong writes.

Benefits of Non-Fed Species

In 2022, aquaculture production surpassed capture fisheries for the first time, reaching 131 million metric tons, according to the Food and Agriculture Organization of the United Nations. Fin fish made up about half of this, with around 62 million metric tons produced. That’s far more than the 37 million metric tons of seaweed and 19 million metric tons of molluscs such as oysters, clams, mussels and scallops. That might sound like a surprisingly large amount of seaweed, but that category includes spirulina, used as a dietary supplement, and carrageenan, used as a gelling agent in products ranging from toothpaste to ice cream to processed meat.

Read the full article about expanding bivalve and seaweed production by Gaea Cabico at Sentient.