https://qz.com/could-offshore-aquaculture-make-fish-farming-more-susta-1849366981?utm_source=email&utm_medium=daily-brief&utm_content=3b1baa85-640a-11ed-befa-d2ed08b7562e
Advocates say it's the future of fish farming, but environmentalists warn about potential impacts
Fish farms, now mostly operating out of tanks on land, are testing the waters in the deep ocean.
With fewer wild fish to catch in the open sea, a new industry is emerging to farm them there instead. Using technology like sensors and cameras, companies are building giant floating farms dozens of miles offshore.
Advocates say this is the future of fish farms, which now account for the bulk of the fish we eat. Fish farming has been fraught with issues, from crowded pens to the use of antibiotics and GMO feed. But in the ocean, there’s more room for fish to spread out and contaminants to dissolve, they say. And industrial offshore fish farming also gives depleted fish stocks a chance to replenish.
“Going forward with the planet you’ve got two choices: Mandate that everyone become vegan and see how well that goes, or move the population towards more efficient forms of animal protein production,” said Neil Sims, founder of Ocean Era, a US-based offshore aquaculture company.
But critics say farming offshore comes with the same problems as doing it on land—plus others that are unforeseen. Last month, several environmental groups filed a challenge in federal court against a permit for a facility 40 miles off the coast of Florida owned by Ocean Era. The Environmental Protection Agency, they argue, did not properly vet the potential harm from wastewater and fugitive fish from the offshore farm. Ocean Era did not respond to a request for comment on the filing.
More than half of the seafood consumers eat these days comes from a farm, according to the UN Food and Agriculture Organization (FAO). In 2022, the industry is expected to produce 92.2 million tons of fish worth $178 billion (pdf).
And fish farming is expected to keep growing. Global fish consumption has increased by 122% since 1990. Meanwhile, the size of legal wild fish catches has shrunk by more than 60% since 1974.
That’s why the FAO estimates more than 60% of the fish we eat by 2030 will be farmed. The agency believes aquaculture will be key to meeting future food demands sustainably. Fish provides animal protein that could substitute more carbon-intensive meat.
So far, aquaculture on land is the most common form of fish farming, the FAO reports (pdf), but advocates say offshore facilities are more environmentally friendly for salt-water fish.
Land-based systems rely on controlled aquatic environments, which require high amounts of energy. “On land, you have to pump the water, provide the oxygen, provide for the filtration of the water…everything costs energy,” said Sims. Offshore, the ocean takes care of a lot of that, he adds. “Why would we be moving a system from the ocean where you have natural tides, the capacity of the ocean ecosystem that can provide the water, the oxygen, the nutrients…why would you not use that?”
Offshore farms can also produce larger amounts of fish. Ocean Era’s commercial partner farms harvest around 300 tons of fish from one 10,000 cubic meter pen, compared to 50-cubic meter pens that harvest about three tonnes of fish per pen on land, Sims estimates.
But offshore presents its challenges. Farms are miles away from land, requiring an industrial setup in places with no infrastructure.
In one word, technology. Cameras and sensors, along with remotely operated vehicles (ROVs) are being used by companies like Ocean Era to determine when fish are hungry or move pens to protect them when there’s a storm.
Hawaiian Kanpachi fish, a type of tropical yellowtail, are farmed by Ocean Era.Photo: Courtesy Neil Sims/Ocean Era