Kushimoto, Japan— Tokihiko Okada was on his boat one recent morning when his cellphone rang with an urgent order from a Tokyo department store. Its gourmet food section was running low on sashimi. Could he rustle up an extra tuna right away?
Mr. Okada, a researcher at Osaka’s Kinki University, was only too happy to oblige—and he didn’t need a fishing pole or a net. Instead, he relayed the message to a diver who plunged into a round pen with an electric harpoon and stunned an 88-pound Pacific bluefin tuna, raised from birth in captivity. It was pulled out and slaughtered immediately on the boat.
Not long ago, full farming of tuna was considered impossible. Now the business is beginning to take off, as part of a broader revolution in aquaculture that is radically changing the world’s food supply.
“We get so many orders these days that we have been catching them before we can give them enough time to grow,” said Mr. Okada, a tanned 57-year-old who is both academic and entrepreneur. “One more year in the water, and this fish would have been much fatter,” as much as 130 pounds, he added.
With a decadeslong global consumption boom depleting natural fish populations of all kinds, demand is increasingly being met by farm-grown seafood. In 2012, farmed fish accounted for a record 42.2% of global output, compared with 13.4% in 1990 and 25.7% in 2000. A full 56% of global shrimp consumption now comes from farms, mostly in Southeast Asia and China. Oysters are started in hatcheries and then seeded in ocean beds. Atlantic salmon farming, which only started in earnest in the mid-1980s, now accounts for 99% of world-wide production—so much so that it has drawn criticism for polluting local water systems and spreading diseases to wild fish.
Until recently, the Pacific bluefin tuna defied this sort of domestication. The bluefin can weigh as much as 900 pounds and barrels through the seas at up to 30 miles an hour. Over a month, it may roam thousands of miles of the Pacific. The massive creature is also moody, easily disturbed by light, noise or subtle changes in the water temperature. It hurtles through the water in a straight line, making it prone to fatal collisions in captivity.
The Japanese treasure the fish’s rich red meat so much that they call it “hon-maguro” or “true tuna.” Others call it the Porsche of the sea. At an auction in Tokyo, a single bluefin once sold for $1.5 million, or $3,000 a pound.
All this has put the wild Pacific bluefin tuna in a perilous state. Stocks today are less than one-fifth of their peak in the early 1960s, around the time Japanese industrial freezer ships began prowling the oceans, according to an estimate by an international governmental committee monitoring tuna fishing in the Pacific. The wild population is now estimated by that committee at 44,848 tons, or roughly nine million fish, down nearly 50% in the past decade.
The decline has been exacerbated by earlier efforts to cultivate tuna. Fishermen often catch juvenile fish in the wild that are then raised to adulthood in pens. The practice cuts short the breeding cycle by removing much of the next generation from the seas.
Scientists at Kinki University decided to take a different approach. Kinki began studying aquaculture after World War II in an effort to ease food shortages. Under the motto “Till the Ocean,” researchers built expertise in breeding fish popular in the Japanese diet such as flounder and amberjack.
In 1969, long before the world started craving fresh slices of fatty tuna, Kinki embarked on a quest to tame the bluefin. It sought to complete the reproduction cycle, with Pacific bluefin tuna eggs, babies, juveniles and adults all in the farming system.
Two scientists from Kinki went out to sea with local fishermen, seeking to capture juvenile tuna for raising in captivity. “We researchers always wanted to raise bluefin because it’s big and fast. It’s so special,” said one of the scientists, Hidemi Kumai, now 79 years old. “We knew from the beginning it was going to be a huge challenge.”
It was more than that. The moment the researchers grabbed a few juvenile fish out of a net, the skin started to disintegrate, killing them. It took four years just to perfect delicate fast-releasing hooks for capturing juveniles and moving them into pens.
“Local fishermen used to say to us, ‘Professors, you are crazy. Bluefin can’t live in confinement,’ ” Mr. Kumai recalled.
In 2011, Kinki lost more than 300 grown fish out of is stock of 2,600 after an earthquake-triggered tsunami hit a coastline 400 miles away. The tsunami triggered a quick shift in tide and clouded the water, causing the fish to panic and smash into nets. Last year, a typhoon decimated its stock. Again this summer, frequent typhoons kept the researchers on their toes as they waited for the breeding season to start. “Oftentimes, all we can do is pray,” said Mr. Okada as he threw a mound of mackerel into the pen using a spade.
It took nearly 10 years for fish caught in the wild to lay eggs at Kinki’s research pens. Then, in 1983, they stopped laying, and for 11 years, researchers couldn’t figure out the problem. The Kinki scientists now attribute the hiatus to intraday drops in water temperature, a lesson learned only after successful breeding at a separate facility in southern Japan.
In the summer of 1994, the fish finally produced eggs again. The researchers celebrated and put nearly 2,000 baby fish in an offshore pen. The next morning, most of them were dead with their neck bones broken. The cause was a mystery until a clue came weeks later. Some of the babies in the lab panicked when the lights came on after a temporary blackout and killed themselves.
Mr. Kumai and colleagues realized that sudden bright light from a car, fireworks or lightning caused the fish to panic and bump into each other or into the walls. The solution was to keep the lights on at all times.
For nearly five decades, Mr. Kumai has lived along a quiet inlet, steps from the university’s research pens. He calls the fish “my family.”
“These fish can’t protest with their mouths so they protest by dying,” he says. “We must listen to them carefully so we catch the problems before they resort to dying.”
Mr. Okada, a researcher at Osaka’s Kinki University, was only too happy to oblige—and he didn’t need a fishing pole or a net. Instead, he relayed the message to a diver who plunged into a round pen with an electric harpoon and stunned an 88-pound Pacific bluefin tuna, raised from birth in captivity. It was pulled out and slaughtered immediately on the boat.Not long ago, full farming of tuna was considered impossible. Now the business is beginning to take off, as part of a broader revolution in aquaculture that is radically changing the world’s food supply.
“We get so many orders these days that we have been catching them before we can give them enough time to grow,” said Mr. Okada, a tanned 57-year-old who is both academic and entrepreneur. “One more year in the water, and this fish would have been much fatter,” as much as 130 pounds, he added.
With a decadeslong global consumption boom depleting natural fish populations of all kinds, demand is increasingly being met by farm-grown seafood. In 2012, farmed fish accounted for a record 42.2% of global output, compared with 13.4% in 1990 and 25.7% in 2000. A full 56% of global shrimp consumption now comes from farms, mostly in Southeast Asia and China. Oysters are started in hatcheries and then seeded in ocean beds. Atlantic salmon farming, which only started in earnest in the mid-1980s, now accounts for 99% of world-wide production—so much so that it has drawn criticism for polluting local water systems and spreading diseases to wild fish.
Until recently, the Pacific bluefin tuna defied this sort of domestication. The bluefin can weigh as much as 900 pounds and barrels through the seas at up to 30 miles an hour. Over a month, it may roam thousands of miles of the Pacific. The massive creature is also moody, easily disturbed by light, noise or subtle changes in the water temperature. It hurtles through the water in a straight line, making it prone to fatal collisions in captivity.
The Japanese treasure the fish’s rich red meat so much that they call it “hon-maguro” or “true tuna.” Others call it the Porsche of the sea. At an auction in Tokyo, a single bluefin once sold for $1.5 million, or $3,000 a pound.
All this has put the wild Pacific bluefin tuna in a perilous state. Stocks today are less than one-fifth of their peak in the early 1960s, around the time Japanese industrial freezer ships began prowling the oceans, according to an estimate by an international governmental committee monitoring tuna fishing in the Pacific. The wild population is now estimated by that committee at 44,848 tons, or roughly nine million fish, down nearly 50% in the past decade.The decline has been exacerbated by earlier efforts to cultivate tuna. Fishermen often catch juvenile fish in the wild that are then raised to adulthood in pens. The practice cuts short the breeding cycle by removing much of the next generation from the seas.
Scientists at Kinki University decided to take a different approach. Kinki began studying aquaculture after World War II in an effort to ease food shortages. Under the motto “Till the Ocean,” researchers built expertise in breeding fish popular in the Japanese diet such as flounder and amberjack.
In 1969, long before the world started craving fresh slices of fatty tuna, Kinki embarked on a quest to tame the bluefin. It sought to complete the reproduction cycle, with Pacific bluefin tuna eggs, babies, juveniles and adults all in the farming system.
Two scientists from Kinki went out to sea with local fishermen, seeking to capture juvenile tuna for raising in captivity. “We researchers always wanted to raise bluefin because it’s big and fast. It’s so special,” said one of the scientists, Hidemi Kumai, now 79 years old. “We knew from the beginning it was going to be a huge challenge.”
It was more than that. The moment the researchers grabbed a few juvenile fish out of a net, the skin started to disintegrate, killing them. It took four years just to perfect delicate fast-releasing hooks for capturing juveniles and moving them into pens.
“Local fishermen used to say to us, ‘Professors, you are crazy. Bluefin can’t live in confinement,’ ” Mr. Kumai recalled.
In 2011, Kinki lost more than 300 grown fish out of is stock of 2,600 after an earthquake-triggered tsunami hit a coastline 400 miles away. The tsunami triggered a quick shift in tide and clouded the water, causing the fish to panic and smash into nets. Last year, a typhoon decimated its stock. Again this summer, frequent typhoons kept the researchers on their toes as they waited for the breeding season to start. “Oftentimes, all we can do is pray,” said Mr. Okada as he threw a mound of mackerel into the pen using a spade.
It took nearly 10 years for fish caught in the wild to lay eggs at Kinki’s research pens. Then, in 1983, they stopped laying, and for 11 years, researchers couldn’t figure out the problem. The Kinki scientists now attribute the hiatus to intraday drops in water temperature, a lesson learned only after successful breeding at a separate facility in southern Japan.
In the summer of 1994, the fish finally produced eggs again. The researchers celebrated and put nearly 2,000 baby fish in an offshore pen. The next morning, most of them were dead with their neck bones broken. The cause was a mystery until a clue came weeks later. Some of the babies in the lab panicked when the lights came on after a temporary blackout and killed themselves.
Mr. Kumai and colleagues realized that sudden bright light from a car, fireworks or lightning caused the fish to panic and bump into each other or into the walls. The solution was to keep the lights on at all times.
For nearly five decades, Mr. Kumai has lived along a quiet inlet, steps from the university’s research pens. He calls the fish “my family.”
“These fish can’t protest with their mouths so they protest by dying,” he says. “We must listen to them carefully so we catch the problems before they resort to dying.”
by Yuka Hayashi, WSJ | Read more:
Image: Jereme Souteyrat for the WSJ
