JAPAN - Numbers of wild torafugu, or tiger pufferfish, a popular luxury food, have been in continual decline, according to a government agency.
The torafugu catch in the Sea of Japan, Seto Inland Sea and other main fishing grounds declined at least 30 per cent over the 11 years to 2013, according to the National Research Institute of Fisheries and Environment of Inland Sea, which is based in Hatsukaichi, Hiroshima Prefecture, and is part of the Fisheries Agency.
Levels of torafugu younger than 1 year old are estimated to be down as much as 60 per cent, which could push catch levels lower still.
As torafugu fishing gets into full swing to meet high winter demand, the Fisheries Agency, local governments concerned and others are scheduled to begin a conference Thursday to discuss resource management.
The Yomiuri Shimbun The institute found that the torafugu catch in the Sea of Japan, Ariake Sea, East China Sea and Seto Inland Sea declined from 383 tons in 2002, the earliest year data is available, to 250 tons in 2013.
Over the same period, the estimated number of young fish under 1 year old went from about 640,000 to about 260,000, suggesting possible overfishing.
Torafugu reach 25 centimeters in length at age 1, 40 centimeters at 2 years old and can grow to 70 centimeters in adulthood.
Among the edible pufferfish species, torafugu are larger and considered a luxury item. There has been an increase in pufferfish farming recently, which has helped cover demand.
Males are mature at 2 years old and females at 3 years old, when they are able to spawn. Young torafugu have particular commercial value, which makes them vulnerable to overfishing.
"If things continue as they are, resource levels will keep declining," said Daisuke Katamachi, a researcher at the institute. "To increase the number of adult fish that can spawn, we need to protect 1-year-old fish in particular. If possible, 2-year-olds and 3-year-olds as well."
Six prefectures that have long been concerned about the declining torafugu numbers - Hiroshima, Yamaguchi, Fukuoka, Saga, Nagasaki and Kumamoto - have independently put in place regulations since 2005, such as setting fishing moratoriums and implementing size limits that require small fish 25 centimeters or shorter to be thrown back when caught.
Longline fishers in Fukuoka Prefecture, which in 2012 had the nation's top catch at 58 tons, have decided autonomously to increase this size limit to 35 centimeters, starting next January.
But the Fisheries Agency has concluded that the issue needs to be addressed over a larger area.
Officials from 20 prefectures, including Ishikawa, Kyoto, Wakayama, Hyogo and Kagawa, are scheduled to join fishing industry and fish market representatives at a conference on torafugu management that starts Thursday in Shimonoseki, Yamaguchi Prefecture.
They are expected to discuss size limits, as well as moratoriums and areas.
"We'd like to deepen the awareness of the crisis situation and discuss what kinds of regulations are feasible," an official of the agency's resource management department said.