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The Wide Net of Seafood Slavery

A crew of Cambodian boys and men work on a Thai fishing ship a couple hundred miles off the coast of Thailand in the South China Sea. Credit: Ian Urbina / New York Times

A crew of Cambodian boys and men work on a Thai fishing ship a couple hundred miles off the coast of Thailand in the South China Sea. Credit: Ian Urbina / New York Times

By David Tickler & Jessica Meeuwig

Labour abuses are allowing fishing fleets to remain profitable while depleting fisheries ever-further from the coast.

Many people think that slavery is a thing of the past, something from the era of colonial plantations and 18th century abolitionists’ efforts to end it. But such practices persist in the 21st century, with the International Labour Organisation and the Walk Free Foundation estimating that more than 40 million people are currently trapped in conditions of “modern slavery” – more than at any other time in history.

While forced marriages make up a share of this estimate, more than half of the people involved are being exploited in labour-intensive industries like agriculture and mining. Because of the survey methods used to identify victims of modern slavery, certain sectors may be underrepresented in the statistics, particularly those that operate in remote workplaces like the open ocean.

In recent years, reports of labour abuses on fishing vessels have emerged from all corners of the world, including Europe, Asia, Africa and Oceania. A key dimension linking cases has been the exploitation of migrant workers from low-income countries on industrial fishing vessels from wealthier countries. For example, Cambodian and Burmese workers are being exploited in neighbouring Thailand or on vessels from South Korea and Taiwan.

This is not simply a case of globalisation gone bad. Trends in the development of global fisheries since the 1950s have created a situation where cheating crew out of fair working conditions is not just the province of the pathologically greedy; it has become a basic condition of economic survival in many fisheries.

Industrial fishing had a growth spurt in the years following the Second World War as food demand rose rapidly and wartime technologies, such as improved navigation and SONAR, found commercial uses. Countries invested heavily in expanding their fisheries, and industrial fishing technologies such as trawling were transferred to developing countries as they emerged from colonial control. As the Cold War intensified, the Soviet Union reorganised its fisheries on a massive scale, creating fleets of factory ships that spilled out of their domestic waters into the Atlantic and Western Pacific.

Global catches grew rapidly as the fishing industry increased its effort and geographic scope, with industrial catches rising from 17.5 million tonnes in 1950 to a peak of 100 million tonnes in 1996. Importantly, catch has declined from “peak fish” levels at a rate of more than a million tonnes per year. This trend continues today.

Thomas Huxley’s “inexhaustible” ocean – where “nothing we do seriously affects the numbers of fish” – has turned out to be smoke and mirrors. While catches grew impressively, what was less evident was that this was only being achieved by throwing increasing amounts of fishing effort at the oceans, and by leapfrogging from one area to the next as local fish stocks declined. Since 1950 the effort required to catch a tonne of fish, in terms of vessel horsepower, fishing technology and fuel, has doubled, while the average distance from port to fishing grounds has almost tripled.

As fish became harder to find and vessels had to move further offshore to fill their nets, governments have provided subsidies for boat-building and fuel costs to keep fleets afloat. Despite this many fisheries, particularly those on the high seas, are still barely profitable, and operators in poorly managed and overcapitalised fisheries find themselves in increasingly dire straits.

It is here that attention turns to the remaining cost-cutting opportunity. Labour costs can make up 30–50% of the operating costs of fishing vessels, so access to cheap and often politically and economically vulnerable pools of migrants offers a tempting solution to this problem. Combine this with patchy or non-existent regulation and control of vessels at sea in some regions, and you have a perfect storm of motive and opportunity for labour abuse.

We wanted to draw the lens back from individual cases of labour abuses in fisheries identified by investigative journalists and non-government organisations, and examine the issue at the global level. Our goal was to identify what we suspected were the systemic drivers underpinning these apparently isolated incidents.

To do this we looked for data that described both fisheries and labour abuses globally. Two datasets currently attempt to do this: the Sea Around Us database of reconstructed fisheries catches, which gives a time series since 1950 of both official and unreported catches by every fishing country, and the Walk Free Foundation’s Global Slavery Index, which estimates the prevalence of slavery for 167 countries worldwide.

We also gathered economic data, including GDP per capita and government fishing subsidies, and used the Sea Around Us’ maps of fishing catches to determine how far each country was fishing away from its home ports – and consequently how far away they were from labour inspectors.

We combined these data to generate a risk model that grouped the major fishing countries of the world into high, medium, and low risk groups based on their fisheries’ performance, governance and economic dimensions. The results have been published in Nature Communications (

We found that countries with the highest risk of modern slavery in their fisheries shared several characteristics. Specifically, these countries provide high levels of vessel and fuel subsidies, which indicates poor profitability in the sector and overcapacity. Poor profitability is also reflected in low catch value per crew member, which further puts pressure on labour costs. High levels of unreported catch in countries’ national records suggests a lack of governance.

Finally, countries with the highest risk of modern slavery are highly dependent on fishing far from home ports and in other countries’ waters, putting them beyond the reach of domestic enforcement. This latter characteristic is worrying given that, with coastal fisheries depleted, the average distance to fishing grounds has increased to 1250 km, or 260% since 1950, making remote observations such as the Global Fishing Watch critical to transparency.

Our results reflect anecdotal reports that key countries in this area are heavily subsidised “distant water” fishing countries such as Taiwan and South Korea, or the poorly regulated and heavily overcapitalised fisheries of Thailand. Offences linked to these countries have occurred both in regions of poor supervision and enforcement. This includes the high seas tuna fisheries of the Pacific and the poorly regulated waters of developing countries in Africa, but also the waters of countries with supposedly well managed fisheries like New Zealand. This suggests that distant water vessels operating in the Exclusive Economic Zones of developed countries should also be subject to better scrutiny.

We also modelled flows of seafood through global trade networks, showing that products from fisheries likely to be affected by labour issues find their way onto the plates of consumers in countries far removed from these abuses. This increases the odds of eating slave-caught seafood by eight to ten times in the US, Europe and Australia. Seafood remains one of the most opaque food supply chains, with practices such as the transhipment of catch between vessels at sea obscuring the origins of fish long before they reach port.

Our research shows how failing and unprofitable fisheries, and a lack of transparency in supply chains, increase the risk that forced labour is used to put seafood on our plates. With a rapidly growing human population and consequent demand for seafood at a time when global catches continue to decline, reformed management of fisheries and the ecosystems upon which they rely is more needed than ever. This requires both the creation and enforcement of appropriate fisheries and labour legislation, and the rebuilding of fish stocks, to address both the opportunity and the need to use forced labour.

Moves towards creating large marine protected areas within national Exclusive Economic Zones and, more recently, on the high seas, point towards a recognition that rebuilding ocean productivity is a key strategy to ensure future human prosperity. Together with negotiations underway at the World Trade Organisation to eliminate the subsidies that buoy excess capacity in the global fleet, this can begin to restore the global industry to profitability.

Wider adoption of labour standards for fishing crew, together with effective enforcement, are needed to protect workers at sea. Net-to-table traceability within the currently complex and opaque seafood supply chain, deploying technologies such as blockchain to ensure tamper-proof information flows, completes a suite of strategies that can remove both the motive and opportunity for labour abuses in fishing.

Australia has the third largest Exclusive Economic Zone in the world, and is deeply involved in the global trade in seafood commodities, both through export of premium products such as western rock lobster, abalone and tuna, and through the import of a wide range of products. Australians collectively consume 330,000 tonnes of seafood annually, of which 70% is imported from overseas fisheries and processors. Australia can contribute to eliminating modern slavery from fisheries by:

  • building on the recently passed Modern Slavery Bill 2018 (Cth) by appointing an independent commissioner to advise seafood companies on minimising the risk of forced labour in their products. Australia’s regional leadership will help other countries to shape their own slavery legislation;
  • ensuring that our trading partners have fair labour laws regulating the hiring, payment and treatment of fishing crews. Key countries for Australia are China, Thailand and Vietnam;
  • supporting international efforts to eliminate harmful subsidies through the World Trade Organisation; and
  • helping to rebuild global fisheries through domestic stewardship, including the creation of large no-take marine parks as ocean replenishment zones.

Seafood is a vital contributor to both human health and livelihoods, but mismanagement and a lack of regulation and supervision have led to systemic abuses that threaten the future of both fish and fishers. With consistent efforts across Australia’s domestic and international dealings, we can help to ensure both a flourishing ocean and safe, rewarding work for those whose livelihoods depend on it.

David Tickler is a PhD candidate supervised by Jessica Meeuwig in the University of Western Australia’s School of Biological Sciences and the UWA Oceans Institute.