The Fisheries Agency is planning to propose rules at an international conference in September that would greatly reduce the catch of immature Pacific bluefin tuna, according to sources.
The government hopes that creating common regulations, out of criteria currently adopted independently by Japan, would prevent overfishing of the high-priced fish.
However, as some nations are expected to object strongly, the proposal's future is unclear.
Last year, the Western and Central Pacific Fisheries Commission (WCPFC), which counts Japan, the United States and South Korea among its members, agreed to cut each nation's 2014 haul of immature fish by at least 15 per cent from the 2002-04 average.
However, the Fisheries Agency determined that, without more significant cuts, bluefin tuna were at risk of disappearing from the Pacific Ocean.
Japan decided independently to limit the haul of immature fish to half the 2002-04 average, or 4,007 tons, starting next year.
On Tuesday, agency officials met with fishing industry representatives to explain how the target could be realised.
Masanori Miyahara, an adviser at the Agriculture, Forestry and Fisheries Ministry, urged the parties to join forces and cooperate for the sake of the future.
Specifically, the yearly 4,007-ton limit is to be split into a 2,000-ton quota for purse seine fishing, from boats using large nets, and 2,007 tons for coastal fishing, such as by fixed shore nets.
For coastal fishing, the nation is divided into six marine regions-north Pacific, south Pacific, west Sea of Japan, north Sea of Japan, Seto Inland Sea and west Kyushu. Catch limits for each region are to be calculated based on hauls from previous years. This would be the first time for the government to set catch limits on a regional basis.
If a region's catch reaches 70 per cent of the limit, an "advisory" would be issued. This would be followed by a "warning" at 80 per cent, a "special warning" at 90 per cent and a "request to restrain operations" at 95 per cent.
However, previous voluntary restrictions have already brought the catch below the new criteria-just 3,815 tons were caught in 2012. The Fisheries Agency, therefore, believes the catch limit will not greatly affect prices.
South Korea to object?
Even if Japan meets the goal of lowering its catch to half the 2002-04 average, the effect would be small if other nations continue toward the less strict "15 per cent or more" reduction target.
The government is, therefore, planning to ask other nations to cut their catches by half as well, at a WCPFC subcommittee meeting in Fukuoka on Sept. 1-4.
Pacific bluefin tuna consumption in Japan makes up 70 per cent of the world total, so making sure bluefin tuna remain available in the Pacific Ocean is vital to the nation's food culture.
The government hopes it can take the lead in the negotiations by pointing to its voluntary decision to make significant cuts.
It appears that South Korea will play a crucial role in the talks.
If the 50 per cent cut were adopted, South Korea's catch would be limited to 718 tons next year. However, since the country caught 1,406 tons in 2012, it could have trouble meeting the target.
A WCPFC meeting is also planned for December. If member nations do not eventually agree to Japan's proposal, there is a possibility of entering next year with no restrictions in place.
The talks will be a test of Japan's negotiation capability.