Despite steady gains in efficiency and hefty subsidies, the world's international fleets of industrial fishing vessels are seeing their catch diminish much faster than previously thought.

And this is happening for a simple reason: because the oceans are running out of fish. This is the core finding of a major study published today in Nature Communications.

If the current rate of fishing continues, warns the study's leader, Professor Daniel Pauly of the University of British Columbia, consumers in rich countries will soon face fewer choices of wild fish and coastal residents of poor countries will see their supply of affordable animal protein dwindle.

The Sea Around Us project, supported by the Pew Environment Group and involving more than 400 collaborators working across the globe for over a decade in a multiplicity of languages, reconstructed the global catch from 1950 to 2010 from a wide array of sources ranging from nutrition studies to economic programs to the archives of former colonial powers.

They found that most countries had reported to the Food and Agriculture Organization their so-called industrial catches - few large vessels, few offloading points - and ignored their obligation to also report artisanal, subsistence and recreational catches, which involve many small vessels and many offloading points and are thus much harder to monitor.

The study's conclusion: the global catch has been 32% higher than the catch that countries reported to the FAO, whose latest assessment rated the global catch "practically stable."

In 2010, the study found the world's fish catch was actually 110 million tonnes, versus 77 million tonnes reported to the UN agency based in Rome, and they found it was declining at three times the reported rate.

Overfishing must stop

"The oceans are in big trouble", Pauly said in an interview. "If we don't start to reduce overfishing now, it's going to be much harder to let the fish stocks grow back to a decent size. The stocks need to grow so they can sustainably yield the amounts we need to feed a population that's growing by a billion people a decade, and at prices that people can afford."

The so-called industrial fleet is made up of large bottom trawlers, purse-seiners and long-liners, mostly from Europe, China and Japan, that fish in the waters belonging to poor countries, having first depleted the fish populations in their own countries.

"The catch is going down by 2% a year, but it looks more stable than it is", Pauly explained. "What they do is deplete one stock and then move onto another, which means they're going to run out of fish in a few decades."

Because these fleets, notably bottom trawlers operating off the rich waters off West Africa, often take coastal fish that the local fishermen depend on, eliminating the industrial fleets would increase the take of the local artisanal and subsistence fishermen. Dyhia Belhabib, the lead researcher for West Africa, discovered that only 40% of the industrial catch was being reported to the FAO.

So the European fleets took three quarters of their catch without paying for it - either their vessels had no license to fish in a country's waters, or they bought a license for a much smaller number of vessel-days, she documented. For Chinese fleets, the figure was an eye-popping 92%.

In Britain, someone blundered

On reporting, Britain fared no better than the rest of the world: the study found that the real UK catch was 35% higher than the catch London reported to the FAO, as an average of the 60-year period. Historically, it rose from 355,000 tonnes in 1950 to 700,000 tonnes in 1972 - a level that fisheries scientist Rainer Froese estimated was sustainable.

"If they had stopped there, today there would be more and larger fish in the water, fishermen would make more money, taxpayers would pay smaller subsidies, there would be more fish in the market and it would be cheaper", said Froese, a senior scientist at the Helmholtz Center for Ocean Research in Kiel, Germany.

Instead, the British catch rose to 950,000 tonnes in 1995 and tumbled down to 430,000 tonnes in 2010 as 7,000 jobs were lost, according to the study's lead UK researcher, Darah Gibson. "There's just not as much fish left", she said.

Most of the unreported catch, she found, was due to a network of secret wholesalers and processor the authorities uncovered in 2005. "For that to happen right under the nose of a well-regulated fishery is pretty amazing", she said.

Solution: end subsidies to big fishing companies

The most effective solution to the global problem, Pauly said, is to eliminate the so-called bad subsidies for fuel and for building new vessels or making existing ones ever more efficient - about $20 billion a year that serve to increase the fishing pressure on a fast-decreasing resource.

These go overwhelmingly to large, well-connected companies and ships. Another $15 billion goes to fund scientific research that allows governments to better manage their fisheries and benefit all fishers.

"The global fish catch is worth about $80 billion, so $20 billion is 25% of their income", explained Rashid Sumaila, a fisheries economist at UBC. "That means that any fishing company that doesn't make a 25% profit is going to go out of business" if these subsidies end.

That would be a good thing, he said. Not only do industrial fleets deplete fish stocks, but many, such as the bottom trawlers, also destroy the sea bottom - a fishing method that's often compared to razing a forest to catch its deer.

"In Somalia in the 80s, the mostly European fleets illegally decimated the fish stocks and they never recovered, so some fishermen turned to piracy", Sumaila said. "And it's starting to happen in the Gulf of Guinea."

Eliminating the subsidies won't translate to higher prices at the supermarket. "Small-scale fisheries get hardly any subsidies and still produce competitive fish", Pauly added. "There is not much of a relationship between subsidies and the price of fish."

A decade ago, Pauly and Sumaila participated in an effort to persuade the members of the World Trade Organization to ban fishing subsidies that increase the efficiency and number of large fishing vessels. Where there's less of those subsidies, there's less overfishing, said Pauly.

That's particularly true in the United States, where it's now illegal to fish anything but stocks that are either healthy (usually at least 50% of their original size) or recovering fast. Australia and New Zealand have also been able to curb overfishing.

At the WTO talks, those countries pushed for a global ban and were reaching a consensus until some countries demanded that in return, the US cut its $20 billion farm subsidies. Washington refused and "That was the end", Pauly said. The Doha Round ended in 2008 and there has been little movement since.

Progress in the Pacific and in Europe

The recently negotiated Trans-Pacific Partnership (TPP) is the first international document that formally bans subsidies to subsidized European and Asian fleets that openly engage in overfishing, such as for the bluefin and bigeye tuna and the thresher shark, and to ships that have been listed as fishing illegally.

It is the first agreement whose members pledge to refrain from extending such subsidies. The treaty also commits members to disclose existing and new subsidies to other members.

If the same rule were applied to Europe, where Froese, the German fisheries scientist, describes his job as "like being a doctor at a waterboarding session", two-thirds of the fish stocks are being overfished - fisheries that would likely cease if their subsidies were cut, he said.

Maria Damanaki, a reformist Greek politician who now runs The Nature Conservancy's oceans programs, tried and failed to make much of a dent in the subsidies in her tenure as the EU's maritime and fisheries commissioner from 2010 to 2014.

However, according to Froese and others, she was able to shift the focus of regulation from preventing the collapse of fish stocks to allowing depleted stocks to grow back so they can deliver their maximum sustainable yield. But national fisheries officials have delayed the implementation of much of her reforms until 2020.

"Since she left, the administrators of previous decades overfishing in Europe and abroad have regained control and continue business as usual, as if the reformed law did not exist", he wrote in an e-mail. But consumers don't need to wait for European officials to act, Pauly said. Non-profit organizations should create what he called an ethical seafood label:

"We have ways of knowing whether a fish has been caught sustainably, and whether the people who grew the coffee we drink were paid a decent wage. Now we need to start a movement for ethical fish that considers the impact of fishing not just on the fishes and the ecosystem, but also on the people who depend on them for survival."

FAO defends its methods

Marc Taconet, who heads FAO's fishery statistics branch, defended its general appraisal that the global catch is stable and the accuracy of his agency's statistics, which are presented with no indication of their margin of error, unlike the Canadian study.

He wrote in an e-mail to The Ecologist: "Comparing reconstructed catches with FAO statistics would be like comparing apples and oranges." Because of the study's "several sources of biases in the method and the wide uncertainty ranges, we express reservations that the paper's conclusions of declining catch trends can be strongly opposed to FAO's reports of stable capture production trends in recent years."

But Dirk Zeller, the paper's co-author, noted that most countries use extensive approximation procedures, so "all countries could estimate uncertainties around their reported data if they chose, but no one does."

Still, the FAO's Taconet added that "This type of research is crucial for stimulating international discussion on unreported catches...We concur with the paper's call upon countries' responsibilities for improving reporting and for mobilizing funding resources."

The paper: 'Catch reconstructions reveal that global marine fisheries catches are higher than reported and declining' is by Daniel Pauly & Dirk Zeller and published in Nature Communications.

Christopher Pala is a science journalist based in Washington, D.C. who has reported on ocean issues for Science, Nature, The New York Times, The Guardian and other publications. See his website.

Books: Christopher is the author of 'The Oddest Place on Earth: Rediscovering the North Pole' and a contributor to 'Underwater Eden: Saving the Last Coral Wilderness on Earth', on Kiribati's Phoenix Islands.

Also on The Ecologist today: 'EU is helping, not harming, UK fisheries' by Griffin Carpenter.