A $600,Secret Confessions (2025) Biyenan Episode 43000 price tag may seem mighty high for just one giant bluefin tuna.

But if every torpedo-shaped tuna cost that much, perhaps the species wouldn't be teetering on the edge of extinction.

A Japanese sushi chain boss paid just such a price on Thursday at Tokyo's 80-year-old Tsukiji fish market.

Kiyoshi Kimura, who owns Kiyomura Corp., bid a winning 74.2 million yen ($632,000) for a bluefin tuna that, at 212 kilograms (466 pounds), weighed as much as two or three people.

This year's winning bid is the second highest in the auction's history. In 2013, the same sushi chain paid a record 155.4 million yen ($1.76 million) for a 222-kilogram tuna.

The Tsukiji auction is among the biggest of Japan's New Year's holiday traditions.

But the star of the show is increasingly threatened by overfishing, which is driven by surging sushi consumption in Japan and around the world.

The Pacific bluefin tuna's population has plunged by more than 97 percent from its historic levels, the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean said in a 2016 assessment.

Stocks of Southern and Atlantic bluefin tuna have also dropped over the past 15 years amid rising demand for the pink- to red-fleshed fish.

In response, global fishing regulators tightened international limits in 2015, halving the amount of bluefin tuna under 30 kilograms that was caught compared to the average caught between 2002 and 2004.

But overfishing, illegal fishing and lax regulations have continued in some areas and threaten to undermine efforts to protect the species, experts say.

In the United States, conservation groups are pushing to grant the Pacific bluefin tuna protection under the U.S. Endangered Species Act.

The National Marine Fisheries Service last fall said such protection may be warranted in the face of the species' staggering decline.

Associated Press contributed reporting.