In the year's first auction at Tokyo's sprawling Tsukiji fish market, the 222-kilogram (489-pound) tuna caught off northeastern Japan sold for 155.4 million yen, said Ryoji Yagi, a market official.
The fish's tender pink and red meat is prized for sushi and sashimi. The best slices of fatty bluefin—called "o-toro" here—can sell for 2,000 yen ($24) per piece at upmarket Tokyo sushi bars.
Japanese eat 80 percent of the bluefin tuna caught worldwide, and much the global catch is shipped to Japan for consumption.
The winning bidder, Kiyoshi Kimura, president of Kiyomura Co., which operates the Sushi-Zanmai restaurant chain, said "the price was a bit high," but that he wanted to "encourage Japan," according to Kyodo News agency. He was planning to serve the fish to customers later Saturday.
Kimura also set the old record of 56.4 million yen at last year's New Year's auction, which tends to attract high bids as a celebratory way to kick off the new year—or get some publicity. The high prices don't necessarily reflect exceptionally high fish quality.
The price works out to a stunning 700,000 yen per kilogram, or $3,603 per pound.
Stocks of all three bluefin species —the Pacific, Southern and Atlantic—have fallen over the past 15 years amid overfishing.
On Monday, an intergovernmental group is to release data on Pacific Bluefin stocks that environmentalists believe will likely show an alarming decline.
"Everything we're hearing is that there's no good news for the Pacific Bluefin," said Amanda Nickson, the director of the Washington-based Pew Environmental Group's global tuna conservation campaign. "We're seeing a very high value fish continue to be overfished."
The population of another species, the Southern Bluefin, which swims in the southern Pacific, has plunged to 3-8 percent of its original levels.
Stocks of bluefin caught in the Atlantic and Mediterranean plunged by 60 percent between 1997 and 2007 due to rampant, often illegal, overfishing and lax quotas. Although there has been some improvement in recent years, experts say the outlook for the species is still fragile.
In November, the 48 member nations of the International Commission for the Conservation of Atlantic Tunas, or ICCAT, voted to maintain strict catch limits on the species, although some countries argued for higher limits. The quota will be allowed to rise slightly from 12,900 metric tons a year to 13,500. Quotas were as high as 32,000 tons in 2006.
A total catch limit on the Pacific Bluefin has been imposed only recently in the eastern part of the Pacific near the United States and Mexico, but not by the intergovernmental group that oversees the western Pacific, Nickson said. So-called effort limits in place now—restrictions on the number of vessels and days fishing allowed—are not effective, she added, and fisherman also are targeting juvenile populations and spawning grounds.
"This poor species is being hit from every angle," she said.