"We were fighting over who had caught more fish, and then I saw my crewmate pushed overboard by the captain," Akbar Fitrian, 29, an Indonesian crewmember says as he recounts an incident aboard a Chinese-owned fishing vessel in 2022. "The ship then started to drive away as my crewmate tried to swim towards us. And then I don't know what happened. The captain never reported the incident."

The seas of Southeast Asia — home to some of the richest in biodiversity in the world — have long been in decline. Since the 1950s, the Center for Strategic and International Studies estimates that 70-95% of fish stocks have been depleted and are at risk of collapse, perpetuated by the rise of industrial-scale fishing, much of which is illegal. Legal overfishing is another factor, and both are propped up by weak regulations, insufficient monitoring and insatiable demand. Approximately half of the world's global marine fish catch comes from the seas of Southeast Asia, according to the U.N., and it comes at a calamitous cost.

In the United States, approximately 50% of the imported seafood comes from Asia, with nearly $6.3 billion in trade coming from China, Vietnam, Indonesia and India alone, according to the U.S. National Oceanic and Atmospheric Administration.

Behind the illicit seafood trade is an opaque world standing at the crossroads of intertwining issues. There is the legacy of brutal human rights violations that have enabled sea slavery to become the norm. Those involved in the efforts of organizations like the international Freedom Fund and Thailand's Labour Protection Network, which work to end modern-day slavery in the region, say many workers are murdered at sea, abused and often brought into a cycle of debt bondage.

There is the lawless nature of the seas, which has emboldened traffickers to exploit desperate fishermen and impoverished casual laborers. Then there are the geopolitical factors at play: In a race to dominate the seas, China and, to a lesser extent, Vietnam, the Philippines, Taiwan and Malaysia have all built outposts and bases on shoals, reefs and atolls. Fishing fleets — of which China has the largest in the world — are fast becoming more militarized as a result.

All of this has imposed a heavy cost on unique ecosystems and led to devastating socioeconomic impacts on artisanal and small-scale fishers.

Three countries illustrate the intersectional nature of overfishing:

Thailand

"Fish were in abundance before," says Mimit Hantele, 53, a member of the Urak Lawoi tribe on the island of Koh Lipe in Thailand. "But now, the fishing season is a lot shorter, the variety of fish is far fewer, and I sell less. So I take tourists out on scuba expeditions to earn money."

For generations, the Urak Lawoi plied the rich waters around them for sustenance. Sea gypsies in a time past, the villagers evolved to rely only on what they could catch and used simple fishing equipment cast from small wooden boats.

Then, in the 1970s, came the big Thai and Malaysian fishing boats. Fishermen on Koh Lipe say the boats fish illegally around the island, appearing only at night to escape detection and in a protected national forest area. The ships use purse seiner nets and demersal trawlers, destroying the coral underneath and, consequently, the habitat for fish. Such overexploitation has led the Indigenous group to turn to tourism to make up for lost income and declining fish stocks. "Fishing is in our blood," Hantele said, but "our way of life has changed. We can't rely only on the fish."

According to a 2001 report from the U.N., roughly 80% of fishers in Southeast Asia at the time were small-scale or artisanal, relying on traditional practices. However, declining nearshore fish stocks have forced many artisanal fishers to venture farther from shore in search of commercially valuable species. Added to that are government subsidies for fuel and tax breaks for commercial fishing vessels, which have propped up the seafood industry. Rapid advancement in maritime technology has made fleets far more effective at finding rich hunting grounds while avoiding detection by switching off their monitoring systems.

Lax regulations on the most destructive types of fishing, particularly demersal trawling and cyanide fishing, the capture of juvenile fish that prevents the replenishment of stocks, the poor oversight of labor laws and the exploitation of workers desperate to earn a living have all contributed to the devastating knock-on effects for communities along coastlines and the potentially irreversible environmental consequences.

In Thailand last year, artisanal fishermen held protests over the rollback of major fisheries reforms implemented a decade ago that had helped to rebuild fish stocks in Thai waters. Thai corporations, which own a significant share of commercial fishing vessels, pushed the government to deregulate the fishing industry to increase their profits. Protestors focused on their concerns that relaxing the rules would revive illegal, unreported and unregulated fishing and lead to increased overfishing. The rollbacks, they argued, would reduce transparency and accountability across the industry and reduce checks on gear and labor. Less transparency would lead to less knowledge about what is left in the sea. In turn, sustainability decreases, hurting artisanal fishers who depend on the sea for sustenance and livelihoods.

The Philippines

The first time Donald Carmen was harassed by Chinese boats off the coast of Palawan was in December 2024. The following February, they harassed him and another fisherman again, getting close enough to hit their outriggers. "They forced us to move away and recorded us with cell phones and cameras. I have been fishing in this area since 2016, and back then, everyone was free to fish. I would catch 400-500 kilograms of fish in a night, about 60 nautical miles offshore. Now, because I don't dare venture out as far, I'm lucky if I catch 200-300 kilograms over three days," Carmen said as he steered his banca just weeks later, on the lookout for Chinese fishing boats and militia.

Illegal, unreported and unregulated fishing is inextricably linked to the geopolitical struggle for maritime dominance in the South China Sea. Over the past two decades, China has rapidly scaled up its fishing militias in a race to assert control over a vast area while trying to meet the country's insatiable demand for seafood. Vietnam, the Philippines, Malaysia and Taiwan have followed suit on a much smaller scale.

The South China Sea — or the East Sea, as Vietnam calls it, and the West Philippine Sea, as it's known in the Philippines — is one of the world's most strategic waterways. China's use of its fishing fleet to control trade routes and dominate territory to create maritime buffer zones threatens the food security and livelihoods of fishers in the region.

While Chinese aggression has persisted for years in areas off Zambales, a province of the Philippines, it has only recently affected waters off the coast of Rizal in Palawan, as China is believed to be building up its presence in the Sabina and Bombay shoals, much closer to the Filipino coast — encroaching on the Philippines' claim to the Kalayaan Island Group — from its original areas of claim like the Spratly Islands and the Scarborough Shoal. Among some of the tactics used by Chinese fishing militias to deter fishermen are water cannons, using swarming and encircling techniques, military-grade lasers and ramming fishing boats to intimidate and drive them from fishing grounds.

As countries in the region militarize their fishing fleets, the cost will ultimately be detrimental to ecological sustainability and geopolitical stability.

Indonesia

In Indonesia, poverty, lack of opportunities and desperation have pushed thousands of Indonesian men into trafficking circles, while others are lured by the promises of a well-paid job in the construction or service industries before being put aboard a fishing vessel unbeknownst to them. Patima Tungpuchayakul, the founder of Thailand's Labour Protection Network, says hundreds of fishermen go missing from commercial vessels each year, and many more are brutalized while facing appalling conditions and inhumane, unsanitary conditions on board, often at the mercy of the captain or the ship's owners.

Labor rights activists at the Migrant Resource Center in Pemalang, Indonesia, fishermen and a widow of a woman still fighting for compensation after her husband's death say agencies in central Java are adept at recruiting Indonesian crew to work primarily on Chinese fishing vessels, entrapping them in a cycle of debt bondage and, in many cases, effectively enslaving them at sea. Workers are not offered compensation for death or injuries unless they or their families were aware of what kind of insurance the vessel owner had for them. In the worst circumstances, they face brutal working conditions and 16- to 22-hour workdays and are often subject to physical violence.

Southeast Asia is still a hub for slave labor, primarily in Thailand and Indonesia, where the seafood trade contributes much of the tuna, shrimp and trash fish used for fishmeal to the supply chains of major retailers and pet food brands in the U.S. and Europe.

"There is now less physical violence and coercion — but coercion is now more debt-based," says Rosia Wongsuban, a program advisor at the Freedom Fund, a nonprofit working to end modern-day slavery. "Working conditions are the same. Because of a labor shortage, there aren't enough workers to operate on vessels, and then the crew needs to take the extra burden."

"In order to work on the fishing vessel, which was Chinese-owned, I was given a loan of 4 million Rupiah," Akbar Fitrian, 29, a fisherman interviewed in Jakarta, explains. "1 million went to paying for fishing equipment, and then I had to work until I paid back the other 3 million. Sometimes, I had to keep borrowing more to continue working to pay off the initial loan. Sometimes I would only end up with enough salary to buy cigarettes. Sometimes I went into the red."

For the nearly 10 million people who rely on these fisheries for their livelihoods and source of protein, the future of Southeast Asia's fisheries hangs in the balance, at the mercy of consumer demand and political will to enforce laws. The region faces not just ecological collapse, but deepening poverty, food insecurity and social instability if illegal, unreported and unregulated fishing continues unchecked. Overfishing occurs because high demand and global overconsumption for seafood far exceed the ocean's ability to replenish itself. Growing markets — especially in China, the European Union and North America — have transformed fish and fish products into a highly profitable global commodity. Exports from Southeast Asia alone amount to over $5 billion worth of fish products to the United States each year, illustrating the scale of international trade. This demand fuels industrial-scale fishing operations such as bottom trawlers and purse seiners, which sweep through vast areas of ocean indiscriminately. Supported by government subsidies, these fleets prioritize maximum yield, even when fish stocks are already severely depleted.

But decline is not inevitable. With stronger regional cooperation, transparent supply chains, corporate accountability and informed consumer choices, Southeast Asia can reclaim stewardship over its waters. The survival of its fisheries — and of the communities that depend on them — hinges on decisions being made now, far from shore.

This body of work, based on a nine-month-long investigation supported by the Fondation Carmignac, is on exhibit at the Bronx Documentary Center through April 26.

Nicole Tung is a photojournalist working primarily in the Middle East and Asia. You can see more of her work on her website, NicoleTung.com, or on Instagram, at @nicoletung.