AAlong Tombo’s crumbling waterfront, dozens of hand-painted wooden boats arrive in the scorching midday sun with the day’s catch for the market fray at one of the Sierra’s largest fishing ports Leone.

In a shady corner of the bustling wharf, Joseph Fofana, a 36-year-old fisherman, mends a torn net. Fofana says he earns around 50,000 leones (£3.30) for a brutal 14-hour day at sea, crammed with 20 men, all paying the owner for the use of his ship. “It’s the only job we can do,” he says. “It’s not my choice. God brought me here. But we are suffering.

Every day, around 13,000 small boats like Fofana’s leave Sierra Leone’s 314-mile (506 km) coastline. Fishing employs 500,000 of the approximately 8 million inhabitants of this West African country, represents 12% of the economy and is the source of 80% of the protein consumption of the population.

But a dozen fishermen interviewed by the Guardian say their catches are rapidly declining due to sustained large-scale overfishing. “Many years ago, you could see fish in the water here, even big ones,” Fofana says. “No more. There are less fish than before.

The fishing community of Tombo blamed the foreign fleets squarely. About 40% of industrial licenses are held by Chinese vessels; Although legal, locals say they pay meager fees for their permits, under-report their catch and contribute little to the local economy.

At the same time, illegal, unregulated and unreported (IUU) fishing is a huge problem, costing Sierra Leone $50 million a year, President Julius Maada Bio said in 2018. Last year, A joint operation by the Sierra Leone Navy and conservation organization Sea Shepherd Global led to the arrest of five foreign-owned fishing vessels in two days, including two Chinese-flagged trawlers that were fishing without a licence.

Those in Tombo who have protested illegal fishing say they face violence from crews. Alusine Kargbo, a 34-year-old mackerel fisherman, says trawler crews threw boiling water at him when he confronted them about fishing in areas where trawling is prohibited. “Before, the trawlers weren’t in our areas, now they are,” says Kargbo. “The difference is so great [in terms of his catches] compared to before, I find it difficult to feed my children.

Others are driven further in search of fish. Ibrahim Bangura, 47, often goes on three-day Atlantic fishing trips, a deadly adventure during the rainy season. But while the potential reward is greater, he says conflicts with Chinese trawlers are more likely. “There are so, so many,” says Bangura. “They disturb my property, ransack my nets. And if you try to stop them, they will fight you.

In addition to dominating authorized markets, China is consistently ranked as the worst offender for IUU fishing in a global index of 152 countries. Across West Africa, illegal trawling is devastating marine ecosystems and undermining local fisheries, which are a key source of jobs and food security. A 2017 study found that Sierra Leone, Senegal, Mauritania, Gambia, Guinea-Bissau and Guinea lose $2.3bn (£1.7bn) a year due to fishing IUU, which represents 65% of declared legal catches.

Some experts warn that coastal communities in Sierra Leone face the devastating consequences of legal and illegal overfishing. “The Chinese fleet has been grabbing the profits from the fishery for 30 years and the impact on fish stocks has been terrible,” says Stephen Akester, adviser to Sierra Leone’s Ministry of Fisheries and Marine Resources between 2009 and 2021. “Resources are disappearing, fishermen are suffering, families are starving. Many only eat one meal a day.

“Imagine working for weeks and not being able to catch food,” says Woody Backie Koroma of the Sierra Leone Artisanal Fishermen’s Union. “They are going into debt. They go to bed without eating.

The pressure is such, says Koroma, that a debt-ridden fisherman in Tombo committed suicide last year after his boat was confiscated by local authorities.

Efforts to manage the sector, including the creation of a coastal exclusion zone that prohibits all but subsistence fishing within the nearest six nautical miles of shore, the installation of motion trackers on industrial trawlers and the establishment of community fishing associations to promote sustainability, have so far had limited impact due to policing and funding issues, officials say. A month-long ban on industrial fishing in 2019 has been criticized as being too short to allow stocks to recover.

“We get a lot of reports and intelligence about illegal fishing,” says Abbas Kamara, an officer with the Tombo Fisheries Ministry. “But it’s hard to corroborate. The trawlers work day and night.

“Fish is very important to Tombo – it’s how people survive – but the fish goes to the Chinese,” Kamara says.

The Chinese Embassy in Freetown did not respond to the Guardian’s request for comment.

Amara Kalone, of the Environmental Justice Foundation, a charity that monitored foreign vessels in Sierra Leone until last year when funding for the project ran out, said fleets are adapting their tactics to evade the restrictions on industrial fishing.

“Semi-industrial vessels are approaching estuaries, and they are in a legal gray area,” he says. “Other crews use very fine monofilament nets, which are illegal but difficult to track.”

According to Salieu Sankoh, coordinator of the West Africa Regional Fisheries Program in Sierra Leone, another major concern is the increase in marauding fishing crews from neighboring countries such as Guinea and Liberia, who catch juvenile fish in protected breeding areas, fatally undermining fish populations. “It is a serious threat to the nutrition of the population,” he says. “Some local boats go out to sea and come back with nothing.”

In Tombo, as skies turn orange on Sierra Leone’s western peninsula and the ocean becomes unusually calm, a sense of desperation is setting in among the many artisanal fishermen struggling to stay afloat.

The poor journeys meant Ali Mamy Koroma, a 40-year-old fisherman with two wives and six children, had to borrow 1million leone (£65) to pay his bills. “I feel like I’m drowning,” says Koroma, slumped against the wall behind Tombo’s covered market. “But I can’t swim. There’s no way out.”