Minoru Nakamura, a fisherman from Iki Island, recalled the biggest tuna he had ever caught, back in 2013. “It weighed 319 kilos. It was so big I couldn’t get it into the boat, and I had to lash it to the hull.” A fish this size being rare, it made the front page of the local newspaper. A photograph showed Nakamura next to his enormous catch, 2.7 meters long, hanging from a crane. He looked proud, but not ecstatic: Their precarious livelihood makes these independent fishermen humble. “I can go for ten weeks without catching anything,” he said at the time; today that sounds like a prophecy. This remarkable fish was one of the last Pacific bluefin tuna over 300 kilos to be caught off Iki.

Iki (population 27,000), in the Sea of Japan between Korea and the Japanese city of Fukuoka, is a pleasant subtropical island with green hills, hot springs, rice paddies, and white sand beaches, but its fishing community is facing an existential crisis. The annual catch of bluefin, highly prized by sushi lovers, has plummeted: It fell from 358 tons in 2005 to less than 23 tons in 2014. Nakamura said: “The little fish, weighing 3-4 kilos, were the first to go, then the bigger ones, and now there are none at all.”

Nakamura and his colleagues have petitioned the Fisheries Agency, part of Japan’s agriculture, forestry, and fisheries ministry, several times. The agency maintains that falling catches are due to climate change. “They say the tuna have moved to the waters off Korea, where we’re not allowed to fish,” said Nakamura, who doesn’t believe it. The fishermen blame the powerful industrial fishing vessels operated by big companies like Nippon Suisan Kaisha (Nissui), which has 10,000 employees. These come from Sakaiminato, a mainland port 400 kilometers northeast of Iki. They started catching adult tuna in the Sea of Japan in 2004, the year Iki’s fishermen began to see their catch fall. Sakaiminato vessels seek out schools of tuna with sonar, then encircle them with a purse seine more than 1 kilometer in circumference. They catch up to 50 tons each time they deploy the net, and a total of 1,500 tons in June and July, when they fish most intensively. The Iki fishermen, who use pole and line, rarely catch more than 1.2 tons a month per boat.

Such intensive fishing is “a heavy burden on the environment,” says Kazue Komatsubara, an ocean campaigner with Greenpeace Japan. “It allows them to catch large numbers of fish of all sizes and species.” According to a report by the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC), nearly 60 percent of all tuna landed by Japanese vessels in the last three decades have been caught by this method.

Many of the bluefin that roam the Pacific Ocean return to the Sea of Japan every summer: This area and the northern part of the Philippine Sea are their spawning grounds. All the fishermen of Sakaiminato have to do is wait with their nets. Their methods anger environmental activists and researchers, who blame them for the decline of the species. “Intensive fishing of tuna during the spawning season is very harmful to the health of the species,” said Toshio Katsukawa of the University of Tokyo’s Atmosphere and Ocean Research Institute. “It’s the complete opposite of sustainable, and if it continues, it will lead to the collapse of the fishing industry in the region. The government should ban the practice.”

“Threatened” species

The impoverishment of the species has been confirmed across the Pacific. In April 2014 the ISC published shocking figures: In 2012 only 6 percent of all bluefin were old enough (three to five years) to reproduce; by 2016 the ratio had fallen to only 2.6 percent. Japan, responsible for 75 percent of all bluefin catches in the Pacific between 1980 and 2014, is now under pressure to introduce serious measures to stem the decline.

The Pacific Rim countries, including Japan, South Korea, and the US, agreed in 2014 to limit fishing of bluefin, at a meeting of the Western and Central Pacific Fisheries Commission (WCPFC), established in 2004 to protect highly migratory fish stocks in the region. Every country now has a quota. Japan, as the biggest bluefin consumer, agreed to reduce its catches by half compared with 2002–04 levels, to a maximum of 4,007 tons for fish under 30 kilos and 4,882 tons for larger fish. Meanwhile, the International Union for the Conservation of Nature (IUCN) has moved the Pacific bluefin to the “vulnerable” category in its Red List of “threatened” species (the stage before “endangered”).

The 314 fishermen of Iki are fighting their own way. In 2013 they set up the Iki Association to Think About Tuna Resources (Nakamura is president) and decided to suspend tuna fishing in June and July until 2017. A member of the association said: “The idea was to pressure the Fisheries Agency to introduce a permanent moratorium during the spawning season.” Another said: “We wanted to show people that if they went on consuming tuna at this rate, they would soon have none.” The association works with fishermen from other parts of Japan, organizing discussions and continuing to negotiate with the authorities and industrial fishing companies in Sakaiminato. In 2016 it was among the finalists at the Seafood Champion Awards, hosted by SeaWeb Seafood Summit, an international conference on the preservation of marine ecosystems.

Things have not turned out as the Iki fishermen hoped. Purse seine vessels out of Sakaiminato continue to operate in the Sea of Japan, under the noses of the Iki fishermen. Restrictions were imposed after the WCPFC agreement, but the quota system takes no account of fishing methods. Greenpeace’s Komatsubara said: “The Fisheries Agency allocated quotas on the basis of catches for 2002–04. The issue of sustainability was not taken into account.” The fishermen of Iki face the same quota reductions (in percentage terms) as the Sakaiminato industrial fishing companies, which is neither logical nor fair. Nakamura said: “Why should we have our quotas cut by as much as the Sakaiminato firms? By rights, they should have to accept bigger cuts than us.”

Low price for a luxury fish

To make matters worse, industrial fishing companies are selling tuna at the shockingly low price of ¥1,000 ($9) a kilo. Katsukawa explained that it’s hard to get a good price for tuna caught during the spawning season because their flesh is less fatty. At Tokyo’s prestigious Tsukiji fish market, some of these tuna fail to find a buyer. These strangely low prices for a luxury fish have escaped the attention of Japanese consumers, though they are attached to sushi, which uses 62 percent of the tuna catch.

To the Japanese, who have been eating tuna since at least 5,500 BC, the idea that the species could vanish because of overfishing seems incredible. Komatsubara said: “People have a hard time accepting that it’s a threatened species, especially as every supermarket sells tuna fillets.” Though there are no official statistics on bluefin, consumption of tuna of all species has fallen from nearly 1.5 kilos per person in a decade, to barely more than 1kg in 2015. Imports of tuna doubled between 2010 and 2016, to 5,000 tons (53 percent of consumption), while tuna farming grew by 40 percent.

Some Japanese fear that stringent measures against overfishing will lead to high-quality tuna disappearing from their diet. “Many people, and businesses, feel that if tuna are going to become extinct, they might as well consume as much as possible while they still can,” said Komatsubara. The Sakaiminato fishermen’s approach—catching large numbers of fish and selling them cheap—reflects this.

This is particularly distressing to the fishermen of Iki because they take every possible care to enhance the flesh of their catches, killing the fish in the traditional way and immediately draining their blood. Kazunari Ogata, general secretary of the association, is proud of the sustainability of their methods: “We don’t catch so many tuna using our poles, but we try to maximise the value of our catch.” Tuna caught and killed this way can cost as much as ¥40,000 ($355) a kilo, and most is bought by smart Tokyo restaurants.

Last July, Iki was battered by storms. The fishermen, unable to put out to sea, gathered in Nakamura’s office and talked about the weather, the closing of their children’s school and, of course, tuna. Since deciding that they would no longer fish in summer, they have been urging the Fisheries Agency to extend the moratorium to all. But the agency maintains it’s better to protect small fish than big ones. Shingo Ota, an adviser to the agency, said the fishermen’s moratorium makes no sense: “Bluefin produce a huge number of eggs—more than a hundred million in some cases—and the vast majority of young fish die before reaching sexual maturity. So the key to the survival of the species is the environment in which the young fish grow. Protecting mature fish that are capable of reproduction will have no impact on small fish numbers.”

“Allow the fish to spawn”

The Sakaiminato fishermen see no reason to stop fishing around Iki. “We’ve been complying with the quotas for the last two years,” said a senior official of a Sakaiminato fishermen’s cooperative. “The authorities have assured us that fishing during the spawning season has no negative impact on stocks, so we’ve got a clear conscience.”

But the agency’s position does not have unanimous support among researchers. Katsukawa said: “Nearly all tuna today are caught before they are five years old, because of overfishing, which means they only spawn once or twice in their lifetimes. If we’re going to protect this resource, it’s very important that we allow the fish to spawn.” The Iki fishermen have asked for studies to determine the effects of their moratorium. The Fisheries Agency has refused, claiming it has no budget for such work.

The Iki fishermen complain of favoritism towards the big purse seine vessel operators. “They regularly give jobs to civil servants retiring from the Fisheries Agency, and that’s why it tries to protect them,” Tominaga said. In the last decade, at least five former senior officials have become advisers or even presidents of fishermen’s cooperatives with links to purse seine vessel operators. Ota admitted: “It’s true. Some former members of our institution are working for them.” But he denied any collusion.

In Iki, exasperation is growing. The independent fishermen get by as best they can by catching less profitable species, notably squid and butterfish. Their incomes have fallen by at last half in the last 12 years. Today, they earn between $1,500 and $3,000 a month; the regional average is $3,400. Forty fishermen have already sought other work. Those who remain are disappointed at how little they have achieved in three years. “Nothing has changed,” said Ogata. Nakamura warned that “if people go on catching tuna during the spawning season, a whole section of Japan’s food culture will disappear.” Given that Japan currently imports more than half of its tuna, there’s a risk the shortage will spread across the world.