The UN has pledged to ensure healthy, productive oceans – but how can this be achieved when demand for fish has never been higher

When I was in Senegal in 2003, the few Chinese vessels fishing along the coast from Mauritania to Liberia were unseaworthy rust-buckets, existing off what licences they could cadge.

Then in the past five years shining new trawlers appeared on the horizon, churned out by subsidised Chinese shipyards, earning their owners handsome subsidies if they travel outside China, where they run on subsidised fuel and exploit subsidised freight rates to get their frozen cargo back home. There seem to be unlimited funds available to buy licences to fish in ways that are far from transparent – and which have long been exploited by other Far East fleets and resourceful members of the European Union.

China’s distant water fleet is now the largest in the world, with about 3,400 vessels fishing in the waters of nearly 100 countries. Researchers estimate that nearly 75% of all the fish it caught came from African waters with almost 3m tonnes from west Africa.

And there is, as far as we can see, a problem. Scientists working for the University of British Columbia, using a new way of estimating the size and value of catches, reported this year that just 9% of the millions of tons of fish caught by the Chinese in African waters is officially reported to the UN. All nations have to report annual catches to the UN’s Food and Agriculture Organisation.

Once, if you wanted to understand how global trends in food consumption were affecting the health of the ocean, you would travel to different countries, stand on the fish dock and watch the boats come and go. Now you get a far better grasp of what is going on from a computer program that tracks fishing vessels by satellite. Focus in on west Africa and you will notice the extraordinary upsurge in the number of Chinese trawlers fishing there in the past four years. The program displays the routes of more than 400 industrial vessels, 220 of them from China – more than any other nation.

Facebook Twitter Pinterest Chinese fishermen unload chub mackerels at Qingdao port Photograph: Hong Wu/Getty Images

Zoom in on the coast of mainland China itself and you will understand why the Chinese fleet ranges across the world from the south Pacific to the Caribbean to bring home the shrimp, sole and tuna for home consumption. Along the shoreline from Hong Kong to Shanghai no sea is visible beneath the blue triangles denoting fishing vessels with their automatic identification system (AIS) switched on. Scientists reported in 2013 that 30% of China’s wild fisheries have collapsed and 20% were overfished.

No one can blame China for trying to feed its 1.35 billion people. But the way it does it is coming under scrutiny, for there are persistent allegations that its fleet is involved in illegal, under-reported or unregulated fishing. In west Africa, some 1.2m tons of fish are caught by 274,000 artisanal fishermen, often in direct competition with industrial vessels.

The result of this conflict is that stocks are in trouble all along the west African coast. Ghana recently had to propose a closed season of several months so fish could breed. The underlying problem is governance, or rather the lack of it. Under Ghanaian law, the beneficial owner of a fishing vessel is meant to be Ghanaian. The 60 licensed Chinese vessels in Ghanaian waters all fly the Ghanaian flag but the fish goes to China.

Stephen Akester, co-ordinator of a World Bank programme designed to improve governance and fish-stock management from Mauritania to Ghana, says the source of the problem lies in the custom of fishing companies buying licences through trawler agents who make payments to politicians that see this as their main source of income. The agency system means more fishing capacity gets licensed than stocks can stand, local fishermen lose out and, if landings are not measured properly, government loses tax revenue. When confronted for buying licences illegally, a Chinese diplomat told Akester, who is British, “You had your turn, this is ours.”

Facebook Twitter Pinterest Fishing crew along Kokrobite beach Ghana. Photograph: Merten Snijders/Getty Images/Lonely Planet Images

The west African example brings home some of the difficulties the world faces in meeting UN sustainable development goal target 14.2, which aims by 2020 to “sustainably manage, and protect marine and coastal ecosystems to avoid significant adverse impacts, including by strengthening their resilience and take action for their restoration, to achieve healthy and productive oceans”. The Overseas Development Institute has identified this target as one of the most difficult to achieve, because it requires a complete about-turn of current trajectories. On the bright side, some 6% of the world’s oceans have now been proposed or designated as protected areas, mostly by developed nations in places far removed from large human populations.

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This target is a more challenging task on the west African coast, where it is often difficult to work out where bending the law ends and breaking it begins. Professor Percy Showers at the Institute of Marine Biology in Sierra Leone explains the impact of foreign fleets: “The stocks are being over-exploited and the situation is not getting better. There is a need for more caution in managing the stocks.” Some fish species, such as the sea breams, are still holding up, but other species have almost disappeared.

The enemy of both marine reserves and fish stocks is what is known as IUU, or “illegal, unreported and unrecorded” fishing. Global losses due to IUU fishing are estimated at between $10bn and $23.5bn (£8bn and £19bn) annually [pdf] and represent between 11 and 26m tonnes of catch.

Steve Trent, executive director of the Environmental Justice Foundation, which has worked against overfishing and IUU fishing in Thailand, Indonesia and west Africa, said: “In order to achieve SDG 14, it is crucial that we put an end to IUU fishing. IUU fishing jeopardises the livelihoods and food security of some of the poorest communities in the world.”

Yet amid the gloom one example stands out and shows what can be done: Liberia. If you look at the computer program mentioned earlier, you will see that there are currently no industrial vessels currently at sea in Liberian waters. None at all. How can this be? Since it began working with the World Bank in 2011, Liberia has instituted a six-mile limit within which no industrial vessels may fish, along with fisheries monitoring that has reduced illegal fishing by 83% according to the ministry of agriculture and fisheries. The result has been that artisanal fishing communities have more than doubled their catch and some communities even report they are catching larger fish.

Facebook Twitter Pinterest Fishing boat in Monrovia, Liberia Photograph: John Moore/Getty Images

This is a rare example of what Akester says should happen everywhere, the reallocation of natural assets to where they are needed most, in the artisanal fleet. The World Bank has worked with motivated politicians in Liberia and is helping to train a new generation of west African fishery managers who have not been contaminated by the agency system.

Liberian agriculture and fisheries minister Moses Zinnah says artisanal fishermen have praised the recovery in stocks

The Liberian agriculture and fisheries minister Moses Zinnah says artisanal fishermen have praised the tremendous recovery in stocks, which has put food on the table and increased income so they can afford to send their children to schools and hospitals.

Tougher fisheries regulations may be in place and actually being enforced, but Liberia still intends to earn foreign currency by selling licences to foreign fleets to catch fish that its own fleet is not equipped to catch, such as tuna. So a five-year partnership agreement has been adopted by Liberia and the EU that will allow 28 purse seiners and six support vessels into Liberian waters under a strict surveillance regime.

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Are there any plans to admit the Chinese, who are hard at work in the other seven west African countries in the World Bank fisheries project? Liberia, Zinnah says, has no policy in place for discriminating against fishing vessels based on nationality. Currently 12 Chinese vessels have requested licences to fish in Liberian waters and these are being considered, provided they fish according to the same rules as EU vessels. Negotiations continue. “The rules are tough and we are not breaking the rules. It has been a bit tough for both sides,” Zinnah observes.

So sustainable use of the sea again hangs in the balance. If the UN goal for sustainable use of the world’s oceans is to be achieved, examples like Liberia’s must not only succeed but multiply.

Charles Clover is a journalist and executive director of the Blue Marine Foundation.

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