Over the past few years, more than 200 distant-water vessels – most of them from Sri Lanka and Taiwan – have parked in the deeper waters along the edge of the bank to catch fish such as tuna, lizardfish, and scad, damaging and destroying seagrass in their wake. Ocean conservationists say conservation efforts are not moving fast enough to make a difference.
“It’s like walking north on a southbound train,” said Heidi Weiskel, acting head of global ocean team for International Union for Conservation Nature.
Since the late nineteenth century, the planet has lost roughly one-third of its seagrasses. Seven per cent more is lost each year – roughly equivalent to a soccer field every 30 minutes.
The Saya de Malha bank, which means 'mesh skirt' in Portuguese, was named to describe the rolling waves of seagrass just below the surface.James Michel Foundation
Like most seagrass environments, the Saya De Malha is home to a myriad of endangered species, including sea turtles.Supplied
Much like trees on land, seagrass absorbs carbon dioxide from the atmosphere and stores it in its roots and soil. But seagrass does it especially fast – at a rate 35 times that of tropical rainforest.
Seagrass also cleans polluted water and protects coastlines from erosion, according to a 2021 report by the University of California, Davis.
As ocean acidification threatens the survival of the world’s coral reefs and the thousands of fish species that inhabit them, seagrasses reduce acidity by absorbing carbon through photosynthesis, and provide shelters, nurseries, and feeding grounds for thousands of species, including endangered animals such as dugongs, sharks, and seahorses.
At a time when at least eight million tons of plastic end up in the ocean every year, seagrass traps microplastics by acting as a dense net, catching debris and locking it into the sediment, according to a 2021 study in Nature.
Seagrasses are frequently overlooked because they are rare, estimated to cover only a tenth of one per cent of the ocean floor.
“They are the forgotten ecosystem,” said Ronald Jumeau, the Seychelles Ambassador for Climate Change.
As a result, seagrasses are far less protected than other offshore areas. Only 26 percent of recorded seagrass meadows fall within marine protected areas, compared with 40 per cent of coral reefs and 43 per cent of the world’s mangroves.
In 2012, UNESCO considered Saya de Malha as a potential candidate to become a Marine World Heritage site, for its “Potential Outstanding Universal Value” – a designation that would have offered the bank protection. But despite describing it as “globally unique” and concluding that it was covered in what is likely the largest seagrass meadow in the world, the agency has not recognized Saya de Malha as such.
A decade later, the United Nations General Assembly adopted a resolution to declare March 1 as World Seagrass Day – acknowledging the urgent need to raise awareness of the global decline in seagrass ecosystems and take action to reverse it. The resolution was sponsored by Sri Lanka.
Speaking at the assembly in May, 2022, the Permanent Representative of Sri Lanka to the UN, Ambassador Mohan Pieris, said seagrasses were “one of the most valuable marine ecosystems on earth,” highlighting, among other things, their outsized contribution to carbon sequestration.
But as the ambassador gave his speech in New York, dozens of ships from his country’s fishing fleet were 14,000 kilometres away, busily scraping the biggest of those very ecosystems he was calling on the world to protect.
Over five hundred years ago, when Portuguese sailors came across a shallow-water bank on the high seas more than 600 nautical miles (1,100 kilometres) east of the northern tip of Mauritius, they named it Saya de Malha, or “mesh skirt,” to describe the rolling waves of seagrass below the surface.
Researchers say the bank is one of the least scientifically studied areas of the planet partly because of its remoteness. The area’s unpredictable depths have also meant that, over the centuries, merchant ships and explorers tended to avoid these waters. It has long been the type of fantastical realm so uncharted that on the old maps it would be designated, “Here Be Monsters.”
More recently, though, the bank has become traversed by a diverse cast of characters, including shark finners, bottom trawlers, seabed miners, stranded fishers, starving crews, wealthy yachters, and libertarian seasteaders.
It took nearly six months for a small Sri Lankan fishing vessel, the Hasaranga Putha, to travel the nearly 2000 miles to the Saya de Malha bank. By the time they arrived, they were desperately short on fuel, water, and supplies.Monaco Explorations
In 2015, an infamously scofflaw fleet of more than 70 bottom trawlers from Thailand dragged their nets over the ocean floor, scooping up brushtooth lizardfish, round scad, sharks, tuna, and other tuna-like species. Their catch would be turned into protein-rich fishmeal that gets fed to chickens, pigs, and aquaculture fish.
The Thai government was not yet a member of the Southern Indian Ocean Fisheries Agreement, therefore none of the vessels were approved to fish in the bank by the Indian Ocean Tuna Commission – two of the main international oversight bodies meant to protect this area of water. Thailand’s Director-General of the Department of Fisheries later confirmed the vessels were “operating in an area free of regulatory control.”
The illegal behaviour of this fleet has since been well documented. At least 30 of the ships had arrived in the bank after fleeing crackdowns on fishing violations in Indonesia and Papua New Guinea, according to a report from Greenpeace. Twenty-four had committed fishing violations, mostly from a lack of valid fishing-gear licences, according to a 2016 Thai government report.
The impact of the Thai fishmeal fleet was “catastrophic” to the Saya de Malha Bank, according to researchers from the environmental non-profit Monaco Explorations, who visited the area in 2022 in an expedition partly sponsored by the governments of Seychelles and Mauritius.
“It seems remarkable that the Thai government permitted its fishing fleet to commence trawl fishing,” the organization said in their final report. “Even a cursory glance” at the existing literature should have dissuaded any trawling, the researchers added.
In 2019, black, potato-sized polymetallic nodules seen scattered on the seafloor drew prospectors to the area in search of cobalt, nickel, copper, and manganese.Southeastern U.S. Deep-sea Exploration/NOAA
Citing a 2008 study that said trawling could “irreversibly destroy seagrass and coral biotopes and cause depletion of particular species,” the report also questioned whether the Thai government’s decision to approve trawling was a “case of complete negligence” or a “deliberate policy to trawl the bank prior to joining Southern Indian Ocean Fisheries Agreement.” It is “astonishing” that trawling was still taking place, the researchers concluded.
The Thai fishmeal trawlers have continued to return annually to the Saya de Malha Bank but typically with fewer vessels than in 2015. In 2023, only two trawlers, the Maneengern 5 and Chokephoemsin 1, were still authorized by the Southern Indian Ocean Fisheries Agreement.
More recently, the bigger fishing presence in the Saya de Malha Bank consists of Taiwanese tuna longliners and Sri Lankan gillnetters. Longliners are vessels that deploy fishing lines, sometimes stretching about 35 nautical miles, which are baited at regular intervals. Gillnetters hang wide panels of netting in the water, keeping them attached to the surface via floating lines.
More than 230 vessels fished in the vicinity of the Saya de Malha Bank between January, 2021 and January, 2024. Most of these ships (more than 100) were from Sri Lanka and many were gillnetters, according to data from Global Fishing Watch. The second largest group were from Taiwan (more than 70 vessels).
At least 13 of these ships from Taiwan and four from Sri Lanka have been reprimanded by their national authorities for illegal or unregulated fishing, with transgressions including the falsification of catch reports, illegal fishing in the waters of countries including Mauritius and Seychelles, and illegal transport of shark fins or shark carcasses with their fins removed.
In 2022, Monaco Explorations sent scientists to document the seafloor, search for sharks and collect samples from the Saya de Malha Bank. A remote-controlled submarine was also used to search the sea column.Monaco Explorations
In November, 2022, several scientists in scuba gear dove over the side of a 440-foot research ship, which had been sent to the Saya de Malha Bank. Their goal that day was to film sharks.
When they were not diving, the scientists submerged a remote-controlled submarine to search the sea column. Ranked as one of the largest and most advanced research vessels in the world, the ship had been sent to this remote stretch by Monaco Explorations to document a seafloor famously lush in seagrass, corals, turtles, dugongs, rays, and other species.
During the three weeks that the research team combed the waters of the Saya de Malha Bank, they didn’t spot a single shark.
The likely culprit, according to the scientists, was the multinational fleet. While many of these ships target tuna species such as albacore, yellowfin, skipjack, and bigeye, they are also catching sharks in huge numbers.
Sharks play a critical role in the ecosystem as guardians of seagrass, policing populations of turtles and other animals that would mow down all the plants if left unchecked. Catching sharks is not easy, nor is it usually inadvertent. In tuna longlining, the ship uses a line made of thick microfilament, with baited hooks attached at intervals. Many tuna longliners directly target sharks using special steel leads designed not to break as the bigger, stronger sharks try to yank themselves free.
To avoid wasting space in the ship hold, deckhands usually throw the rest of the shark back into the water after they cut off the fins, which can sell for one hundred times the cost of the rest of the meat. It’s a wasteful process and a slow death, as the sharks, still alive but unable to swim, sink to the seafloor. To offset poverty wages, ship captains typically allow their crew to supplement their income by keeping the fins to sell at port, off books.
The 2015 Thai fleet routinely targeted sharks in the Saya de Malha Bank, according to an investigation conducted by Greenpeace. Trafficking survivors who worked on two of the vessels – the Kor Navamongkolchai 1 and Kor Navamongkolchai 8 – told Greenpeace that up to 50 per cent of their catch had been sharks. (Questions about their working conditions linger. Conditions on many distant-water fishing boats are notoriously brutal with violence, trafficking and neglect common.)
Since then, the Thai presence in the Saya de Malha Bank has diminished, however the Sri Lankans and Taiwanese have continued to fish the bank intensely. Of the more than 100 Sri Lankan vessels that have fished in the Saya de Malha since January, 2022, when the country’s fleet first began broadcasting vessel locations publicly, about half – or roughly 44 – use gillnets, according to vessel data from the Indian Ocean Tuna Commission.
These gillnetters operate across the Indian Ocean, and a number of the vessels were observed at the bank by the 2022 Monaco Explorations expedition. Sharks are especially vulnerable to gillnets, which account for 64 per cent of shark catches recorded by the Indian Ocean Tuna Commission.
In August, 2024, a video was posted to YouTube showing dozens of shark and ray carcasses recently unloaded from vessels in the Sri Lankan port of Beruwala. In the video, a man butchers one shark with a machete, dark blood pooling on the concrete of the harbour as he hacks at the body, removing its fins and hauling entrails from the carcass. Several videos showing similar scenes – hundreds of dead sharks, some without fins, being unloaded from fishing vessels and lined up on Sri Lankan harbors for sale to local exporters – have been uploaded to YouTube over the past two years.
The videos offer a window into the booming trade that has decimated local shark populations: About two-thirds of Sri Lanka’s domestic shark and ray species are listed as threatened by extinction by the International Union for Conservation of Nature. That threat has now moved further afield, to the high seas far from Sri Lankan shores – including to the Saya de Malha, putting yet more pressure on the threatened ecosystem.
In 2022, a Sri Lankan fishing ship, the Hasaranga Putha, approached a Monaco Exploration research vessel begging for fuel, water, and cigarettes.
The scientists aboard the research vessel provided assistance to the Sri Lankans by delivering water, food, and soda, but they did not have the type of fuel the smaller vessel required.Monaco Explorations
Historically, Sri Lankan vessels have targeted sharks in domestic waters. Between 2014 and 2016, for example, 84 per cent of reported shark catches came from domestic vessels, according to research into the Sri Lankan shark and ray trade published in 2021.
But as domestic populations declined, vessels – among them the fleet of gillnetters – moved to the high seas, leading to a new boom in the fin trade. Sri Lanka’s annual exports of fins quadrupled in the past decade, according to UN Comtrade data, with 110 tons exported in 2023, primarily to Hong Kong, compared to just 28 tons in 2013.
Tracking data also shows that more than 40 of the Sri Lankan vessels do not publicly broadcast their location while in the bank. This practice is a persistent barrier to ocean conservation because it masks the true scale of the fleet or hides when these ships plan to engage in illegal behavior.
However, these dark vessels can be tracked by monitoring the signals from their fishing buoys. Sri Lankan vessels can have up to a dozen, each with its own unique identification signal, Sri Lankan fishing records indicate.
At least one of these hidden vessels that fished in the Saya de Malha between March and June, 2024, the IMUL-A-0064 KMN, was detained last August by Sri Lankan authorities with over half a ton of oceanic whitetip shark carcasses aboard, all with their fins removed.
A shipment of shark fins smuggled in from Sri Lanka, including some from endangered species, are seen on a street in Hong Kong in 2018. Catching oceanic whitetip sharks and removing shark fins at sea is prohibited under Sri Lankan law.Sea Shepherd Global/Getty Images
Catching oceanic white-tip sharks is prohibited under Sri Lankan law, as is the removal of shark fins at sea. This was not an isolated incident: Sri Lankan authorities have seized illegally harvested shark fins on at least 25 separate occasions since January, 2021, according to press releases from the Sri Lanka Coast Guard.
Though Taiwanese law does not allow vessels to engage in shark finning, the practice still takes place. In a sample of 62 Taiwanese vessels fishing on the high seas between 2018 and 2020, half engaged in shark finning, according to the Environmental Justice Foundation, which interviewed former crew on the ships.
At least one of the Taiwanese vessels that fishes in the Saya de Malha, the Ho Hsin Hsing No. 601, was penalized in May, 2023 for having dried shark fins in its vessel hold. The vessel operator was fined the equivalent of $123,000 and had their fishing license suspended for a month. The ship had last fished in the Saya de Malha between September and October, 2022.
Ocean scientists say the presence of these ships poses a dire threat to biodiversity in the bank.
Jessica Gephart, a fisheries-science professor at the University of Washington, explained that the Saya de Malha Bank is a breeding ground for humpback and blue whales, which can be injured or killed by ship collisions.
“Bycatch is definitely the largest known threat from longline fishing, but aside from that, there is a risk of entanglement by marine mammals and long-term risks posed by abandoned gear,” she said.
James Fourqurean, a biology professor at Florida International University, said the worry is not just that fishing vessels may cut down the seagrass. These ships also risk causing turbidity, making the water opaque by stirring up the seafloor, and thereby harming the balance of species and food pyramid, he said.
The Saya de Malha Bank remains unprotected by any major binding treaties largely due to an anemia of political will by national authorities and a profits-now costs-later outlook of fishing interests.
International institutions known as regional fisheries-management organizations are supposed to regulate fishing activities in areas of the high seas such as the bank. They are responsible for establishing binding measures for the conservation and sustainable management of highly migratory fish species. While their roles and jurisdictions vary, most can impose management measures such as catch limits.
The Southern Indian Ocean Fisheries Agreement and Indian Ocean Tuna Commission are intended to protect the Saya de Malha.
However, these organizations are often criticized by ocean conservationists because their rules only apply to signatory countries and are crafted by consensus, which opens the process to industry influence and political pressure, according to a 2024 Greenpeace report.
The Saya de Malha, as an archetypal example of these limitations, is governed by the Southern Indian Oceans Fisheries Agreement. Sri Lanka, the home of the bank’s largest fleet, is not a signatory.
WATCH:
Deaths and disappearances on distant-water fishing vessels
Content warning: This video contains brief images of deceased and mentions of death by suicide. Fishing is the most dangerous job in the world with more than 100,000 people dying at sea a year. Ae Khunsena is one example; he jumped overboard from a Thai fishing vessel in remote waters and was never seen again. The vessel was working the Saya de Malha Bank in the Indian Ocean. Hundreds of miles from the nearest port, it is one of the most remote areas on the planet, which means it can be a harrowing workplace for the thousands of fishers who make this perilous journey.
Outlaw Ocean
This story was produced by The Outlaw Ocean Project with reporting and writing contributed by Maya Martin, Joe Galvin, Susan Ryan, and Austin Brush.