If something cannot go on forever, it will stop
— Herb Stein
Sometimes a picture is worth a thousand words.
Kiyomura Company's President Kimura, who runs a chain of sushi restaurants, wields his cutting sword as he shows off the big Pacific Bluefin Tuna he is about to dismember. This 489 pound fish fetched a record price of 1.78 million dollars. Image source.
The bluefin tuna is considered one of the more valuable fish in the world, said the report from PRI's The World.
Gee whiz! — I wonder why?
To answer that question, we can consult Bloomberg's Tuna Sold at Record Price Is Overfished, Study Says, and the study it cites (pdf). This story contains a priceless quote.
The number of Pacific bluefin tuna, a fish that fetched a record 155.4 million yen ($1.78 million) in a Tokyo auction last week, dropped 96.4 percent due to decades of overfishing, the Pew Environment Group said.
The bluefin’s numbers have plummeted because of inadequate fishing regulations in the species’ western Pacific spawning area, Amanda Nickson, Pew’s director for global tuna conservation, said today in a phone interview. The stock assessment by the International Scientific Committee for Tuna and Tuna-Like Species in the North Pacific Ocean, a joint U.S.- Japan research group, is “shocking,” said Nickson...
“You have this incredibly valuable, sought-after fish where the first one of the year can be sold for over $1.7 million, yet it’s been allowed to become depleted to this truly frightening point,” Nickson said. “That is just not a situation that can continue.”
You're right about that, Amanda! — in every sense, this is just not a situation that can continue.
I couldn't find that 96.4% number the Pew report on the Japanese study came up with, but let's look at the spawining stock biomass (SSB) for Pacific Bluefins, and 4 model projections of future biomass and future total catch.
Historic SSB on the left, 4 model-run projections on the right. The only real mystery is why stocks recovered in the early-mid 1990s. Remember, these SSB numbers reflect the biomass of a fish species that was already depleted long before 1960. That's the shifting baseline I've talked about.
Needless to say, that big Pacific Bluefin fetched $1.78 million because tuna of this age and size are now extremely rare in the northern Pacific. (A long time ago, such fish were common.) Yet the optimistic projections given in the study (right panel above) show none of the fluctuations or the downward trajectory in bluefin SSB since the late-1990s, trends which are obvious in the historical data (left panel above).
Well, let's see ... the organization who did the study is a Japanese group, and Japan is the largest consumer of sushi made from bluefins.
Do we have a name for this kind of blindness? We sure do! What do we call it?
More priceless quotes from Bloomberg—
Japanese officials have reviewed the International Scientific Committee’s report and plan to discuss regulations or other measures to be implemented in response, Shuya Nakatsuka, deputy manager of the Japan Fisheries Agency’s international unit, said by phone today. The population decline would be discussed when the WCPFC meets in September, he said.
“There have been cases in the past where the population of bluefin tuna has been low, but have recovered,” Nakatsuka said. “Still, the results show that the population is very low this time.”
Stocks declined 83 percent to about 22,600 metric tons in 2010 from about 132,000 in 1960, when they had already begun to be depleted, said [Amanda] Nickson, citing the report by the committee. More than 90 percent of bluefin that are caught are juveniles that have not yet reproduced, she said.
And, Oh, did I neglect to mention that the study said that related species like Bonita and Mackeral are also severely overfished?
I want you to take another look at the big smile on Kiyomura president Kimura's face as he prepares to slice into that giant bluefin laying on the table before him. Take a good, hard look at it now, because sometime in the not-so-far-flung future, Kimura won't be smiling like that ever again.