Big news is coming from Japan about the New Year tuna auction at Tokyo's Tsukiji market. The auction on Thursday saw a bluefin tuna sold for a mind-boggling 74.2 million yen ($642,310).

The top bidder for the 212kg (467.38 pounds) fish was Kiyoshi Kimura, president of Kiyomura Corporation, which runs the Sushi Zanmai restaurant chain. In the auction, Kimura outbid all rivals for the sixth year straight.

The man-sized fish was caught off the coast of northern Japan's Aomori prefecture. The price is obviously quite high compared to the 14 million yen posted in 2016. Still, the current price is a dwarf compared to the record 155 million yen paid by the Kimura in 2013.

After winning the bid, a jubilant Kimura posed with a big knife in front of the dark-silvery fish. He said that the bid was "a bit expensive, but I am happy that I was able to successfully win at auction a tuna of good shape and size."

Thanks to the passion for costly tuna auctions, Kimura is known by the nickname "Tuna King".

The Tsukiji market's first auction in the New Year is a big business as it draws hordes of restaurants which are keen to convert the publicity into a marketing opportunity.

Endangered Tuna

Even as big bucks are chasing bluefin tuna, the outlook on the fish, also known as the King of Sushi, is grim.

"This tuna is being fished at rates up to three times higher than scientists say is sustainable," said Amanda Nickson, director of global tuna conservation at The Pew Charitable Trusts in a recent report.

Many environmental groups including Pew have called for a two-year ban on commercial fishing of the bluefin tuna.

Japan tops the charts as the biggest consumer of Pacific bluefin tuna, where 80 percent of all bluefin tuna caught worldwide is consumed.

Data show bluefin tuna population has ebbed 97 percent from its historic levels because of overfishing. According to the International Scientific Committee for Tuna in the North Pacific Ocean, the current "unfished" population is just 2.6 percent, down from an already low 4.2 percent shown in a previous estimate.

Highlights Of Bluefin Tuna

Bluefin tuna has many unique characteristics including a larger life span of 40 years. Moving across oceans, bluefin is a fast swimmer and can dive more than 4,000 feet.

In terms of movement, bluefin tuna acts like torpedoes with retractable fins and sharp vision. They are huge predators and eat up schools of fish such as mackerel, eels, and herrings.

There three kinds of bluefin tuna — Atlantic, Pacific, and Southern. The bulk of the Atlantic bluefin tuna is caught from the Mediterranean Sea.