TOKYO -- One morning in early October, a North Korean fishing ship sank after colliding with a Japanese patrol vessel, requiring all 60 fishermen to be rescued off the Sea of Japan coastline.
The incident was a reminder of how North Korean vessels, as many as 1,000 strong during peak season, regularly descend upon Yamato Bank, a prime area for catching squid and other seafood.
But according to Japanese fishermen, the bigger threat comes from the massive trawlers hailing from China.
Those who belong to Japan's Ishikawa Prefecture of Fisheries Co-operative Associations, specifically the Ogi branch in the town of Noto, have long boasted of leading hauls of Japanese common squid throughout the country. But their catch has been on free fall throughout the past decade.
The scarcity of squid this year is without precedent. The haul averaged 59 tons per ship between June and the end of September. The volume is down by more than 60% from a year earlier, and only a fifth of what was caught 10 years ago.
Yamato Bank is the main fishing spot for the 13 fishing boats from Ishikawa Prefecture. But not only have the crew encountered competing fishermen from North Korea, they say they have also spotted Chinese vessels five times bigger than what is legally allowed.
Japan caps the size of offshore fishing ships at 200 tons. New vessels are often built within the 190-ton range to stay within regulation. But among the hundreds of Chinese vessels fishing around Yamato Bank, some as large as 500 tons to 1,000 tons can be seen.
Chinese vessels use trawling nets to catch squids, a practice Japanese fishermen have abandoned to maintain quality. Sometimes the nets are pulled simultaneously by two Chinese vessels.
"The method takes everything that's there," said a director of the Ogi co-op branch. "It's only a matter of time before resources are exhausted."
Yamato Bank lies in Japan's exclusive economic zone, which bans foreign vessels from operating in the area without Tokyo's permission.
Nevertheless, patrol boats from Japan's Fisheries Agency issued 5,315 warnings telling foreign-flagged boats to leave last year. The number has multiplied 12 times since 2012. Separately, the Japanese Coast Guard lodged 1,624 warnings to foreign fishing ships to exit the zone that same year.
The Ogi co-op branch, however, said Japanese fishing boats can be ordered not to approach fleets of foreign-flagged ships that have massed in the zone. As a result, non-Japanese fishing boats are able to operate with near impunity.
The squid population was already being affected by environmental changes in the ocean, and poaching has exacerbated the problem. The two forces, in addition to Japanese fishing ships being prevented from approaching a prime fishing spot, leaves little wonder as to why the haul of squid is decreasing each.
Seafood prices have risen globally due mainly to consumption by developing countries. In turn, Chinese and Taiwanese fishing boats have been catching massive volumes of saury and mackerel near Japan's exclusive economic zone off the northeast coast of Honshu. Last year, 440,000 tons of saury were caught in the northern Pacific, but Japan only accounted for about 30% of the share.
Japan, China and South Korea are all members of the North Pacific Fisheries Commission, a body that regulates the number of fishing ships. Last year, the commission reached an agreement that sets quotas on catches. Yet unregistered vessels still populate international waters near northern Honshu.
At the United Nations and other international bodies, many are voicing concerns about illegal, unreported and unregulated fishing. In Japan, both the Fisheries Agency and the Coast Guard are under mounting pressure to deal with foreign fishing vessels.
One reason why Yamato Bank has drawn many non-Japanese fishing boats is because Russian officials have cracked down on poachers in waters surrounding Hokkaido. If Japan is viewed as lax, then Yamato Bank will fall under virtual control of foreign fishing ships.