High Seas Fishing Isn’t Just Destructive—It’s Unprofitable

Government funds prop up more than half of fishing in the open ocean, a new study reveals.

By Sarah Gibbens
Published 8 Jun 2018, 16:18 BST
A fisherman checks his fishing lines while fishing on the high seas. The high seas is ...
A fisherman checks his fishing lines while fishing on the high seas. The high seas is defined as the open waters outside a country's exclusive economic zone, generally 200 miles past the shore.
Photograph by Chris Johns, National Geographic Creative
This study was funded in part by the National Geographic Society's Pristine Seas initiative. Learn more.

A fish’s journey from ocean to plate may not be as straightforward as it sounds.

Most people are aware that a fisher, a grocer and a cook were involved in that journey. But a new study finds that governments lend a hand, too—and a mighty big one.

A paper, published in the journal Science Advances, found that as much as 54 percent of high seas fishing would be unprofitable were it not for governments covering some of the industry's costs. To a lesser degree, the study also found that exploited labour and underreported catch may explain how large vessels afford to fish in international waters.

“The study confirmed that much of the high seas fishing does not make sense,” says study author and National Geographic Explorer-in-Residence Enric Sala. “If it's ecologically destructive and economically unprofitable, why don't we end all high seas fishing?”

In 2016, just over 3,600 vessels actively fished on the high seas—the open ocean outside any country's jurisdiction. To better understand this impact, the research team of ecologists, data scientists, and economists looked at the most recent cost datasets available, from 2014. They found that the total cost of fishing in that year ranged anywhere from 6.2 to 8 billion USD (£4.6 to £6 billion) and that subsidies totalled around 4.2 billion USD (£3.1 billion).

By far, their data showed that China and Taiwan net the fewest profits in the sector, while exerting some of the most effort. Russia was also shown to have an unprofitable fishing industry, even with subsidies.

However, subsidies weren't just given to unprofitable fishing vessels. The study also found that marginally profitable companies in Japan, South Korea, Spain, and the U.S. had their profits boosted by government subsidies.

This boat is fishing for tuna, a species commonly fished out of the high seas.

“There are three different categories [of subsidies],” says University of British Columbia economist Rashid Sumaila, one of the study's authors. He and his colleagues began compiling data on fishing subsidies in 2000, and they found that not all subsidies were harmful. Some were ambiguous and hard to categorise. Others were beneficial and went toward activities like sustainable management, research, and regulation enforcement.

Other subsidies helped companies increase their carrying capacity—essentially these allowed boats to fish more in fisheries that might be at risk of depletion. Rather than directly providing a fishing company with a check, governments may offer tax breaks, help pay for fuel costs, provide money to upgrade gear, or fund infrastructure like ports.

Spying From Space

Open ocean outside EEZs, generally 200 miles beyond the shore, is free game. The UN's Food and Agriculture Organisation outlines a code of conduct on these high seas, but regulation is minimal and enforcement is scant.

What's more, vessels often have a competitive interest in not sharing details about their activities.

To compile data for one of the world's most inaccessible regions, marine data scientist and study author Juan Mayorga turned to a program called Global Fishing Watch that tracks vessels from space using the satellite-transmitted signal from AIS—Automatic Identification System—that vessels are required to transmit. Earlier this year, he used the data to find that industrial fishing covers a third of the planet.

“When we first came up with this idea, we did not have a good handle on what fishing on the high seas looked like,” says Mayorga. Over a two-year period, he determined how many vessels were operating in the high seas and how often, though he adds that the study's data can't account for all high seas fishing activity. Some vessels forego AIS or turn it off to be covert intentionally.

With the data for the ships they could measure, Mayorga used models to estimate fuel costs based on a vessel's size, location, distance travelled, and speed. He could also see the type of vessel and what it was fishing for, which helped him estimate needed labour. Looking at existing information on minimum wage laws and typical cost of labour, Mayorga was able to estimate labour costs on a scale.

He notes, however, that this estimate is the least certain part of the study, because reports from several non-governmental organisations show the fishing industry has a history of exploitative labour practices, verging on or directly resulting in slave labour in some regions.

“Labour is what drives the uncertainty in our analyses,” he says.

With his range of operating costs, Mayorga then estimated the haul each vessel was bringing to market. The study's authors suspect that catch may be underreported in some cases.


All-in-all, industrial fishing on the high seas is a relatively small portion of global fishing—accounting for only six percent of all fishing activity. Fishing subsidies in EEZs have been controversial, with the World Trade Organisation considering banning them in the past decade. So why subsidise fishing for more expensive fleets that yield smaller returns, the study's authors ask.

According to a representative from the UN's Food and Agriculture Organisation, food security is often cited as a major reason for providing subsidies to fishing industries. But a statement published by the agency in 2016 acknowledges a need to regulate subsidies to ensure sustainability.

“Fisheries subsidies warrant concern,” says FAO representative Christopher Emsden, adding, “Care is needed as they can serve development purposes in some cases, (although these would likely be for small-scale fishers and not those featuring in the study).”

In addition to depleting fisheries, high seas fishing subsidies also threaten important natural habitats, says Sala. Deep-sea bottom trawling, one of more common high-seas fishing practices, is problematic, he notes.

“Trawling is one of the most destructive practices on the planet,” says Sala. “They have nets so large they can hold a dozen 747 jets. These huge nets destroy everything in their path, including deep-sea corals. And it would not be profitable without subsidies.”

In addition, all three researchers noted that high-seas fishing may perpetuate exploitation.

“[Unprofitability] has implications about the extent to which unfair labour practices drive fishing on the high seas,” notes Mayorga.

The Future of High-Seas Fishing

Transparency, whether because industry officials intentionally withheld information or governments lacked records, presented a major hurdle for how researchers comprehensively assessed the high-seas fishing industry.

To combat what they say is an economically and environmentally unsound practice, the research team says increasing transparency is key. More stringently enforcing AIS, for example, is one way Sala says regulators could monitor the full impact of high-seas fishing.

Sumaila would like to see the World Trade Organisation ban or roll back fishing subsidies, but despite extensive discussion at the organisation progress has been minimal. The last vote was shot down in December of last year, primarily due to procedural hurdles.

In an emailed statement, the WTO responded to inquiries about high seas fishing subsidies by saying: "Governments of the world have entrusted the WTO with the responsibility of tackling fisheries subsidies that are harmful to our oceans. Last December, at our ministerial conference in Buenos Aires, all WTO members committed to securing a deal on this issue... by the end of 2019, and this work is now well underway. This is one of the important issues of our time. It requires a shared solution. The world is watching."

The high seas have sometimes been seen as an avenue for countries to compensate for other overfished waters. China, for instance, has experienced extensive overfishing in its own waters, and a study published in April 2017 found the country trying to compensate by fishing in waters as far as western Africa.

Depleting fisheries is a growing problem. Of the 600 fisheries monitored by the FAO, more than half are depleted to the point of yielding little to no catch.

Last December, the U.N. also began talks to create a framework to protect high-seas biodiversity. Negotiations are expected to be ongoing for the next two years.

The high seas doesn't belong to any one country, which means regional governments often clash during negotiations. In the past, some have objected to long-term changes, hoping to leave the door open to commercial opportunity, while others are worried they may be impacted by declining biodiversity.

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