Toyota-affiliated fish farm sets sail on trade of cultivated Pacific bluefin tuna

January 30, 2012

By KAZUKI NOBUHARA / Staff Writer

Taking advantage of the world's first complete cultivation of the prized bluefin tuna by a university, a Nagoya-based trading house, affiliated with Toyota Motor Corp., is now shipping fry to fish farms with an eye on meeting growing demand in China and elsewhere.

The team hopes to supply about 50,000 young fish annually in two to three years' time, and satisfy a growing appetite while fishing quotas put a strain on supplies.

Building on more than 40 years of often frustrating academic research, a fish farm in the western Goto islands in Nagasaki Prefecture shipped about 14,000 young baby Pacific bluefin tuna to commercial culturing companies in Nagasaki and Kagoshima prefectures in November.

The breakthrough, the first time Pacific bluefin tuna have been grown in marketable quantities, has raised the prospect of a self-sustaining aquaculture that can meet the demand for the game fish without depleting dwindling wild stocks.

The Tuna Dream Goto project, run by Kinki University and the trading house Toyota Tsusho, is looking to plug a gap in supply created by increasingly strict restrictions on fishing for wild Pacific bluefin tuna. In 1995, 78,000 tons of the fish were landed but that was down to 40,000 tons in 2009.

“We want to offer about 200,000 Pacific bluefin tuna a year through the complete culturing (process),” said Shigeru Miyashita, a senior member of Kinki University’s Fisheries Laboratory in Shirahama, Wakayama Prefecture.

The project plans to increase that figure to 50,000 within two or three years, which it said will make the project profitable.

“Demand for marine products is sharply increasing, especially in China. It is certain that at some stage there will be no other way than depending on complete culturing,” said Satoshi Nishide, Tuna Dream Goto president.

The joint project is only two years old but is relying on decades of research by Kinki University’s pioneering laboratory, which first succeeded in raising large quantities of Pacific bluefin tuna from eggs in 2002.

The hatchlings are raised to 30-centimeter, 6-month-old tuna in 30-meter-wide pens off the coast of the Fukuejima island in the Goto island chain. They are then painstakingly gathered over two months and sent to the culturing companies in Nagasaki and Kagoshima, which are tasked with raising the fish for three years to a length of about one meter. Once they reach that length, they could be sold on the open market.

The fish raised at Fukuejima island are not taken from the sea, but are hatched from eggs laid by tuna raised by the university. That is vital, because it means the farming process does not deplete wild stocks.

The young fish are extremely vulnerable and, to minimize damage when the tuna swim at high speeds in

A worker gathers Pacific bluefin tuna from a pen

on Fukuejima island in Goto, Nagasaki Prefecture.

(Provided by Tuna Dream Goto)

circles, Kinki University researchers have developed rounded net walls for the pens. Decades of research also underlined the need for relatively large pens, after it was found that overcrowding harmed the fish. That meant bringing in Toyota Tsusho, a group company of major carmaker Toyota Motor Corp., for the funding.

Pacific bluefin tuna is not the only fish that is close to complete domestication. The National Research Institute of Aquaculture (NRIA), part of the government-affiliated Fisheries Research Agency, is studying technologies to raise more than 10,000 Japanese eels a year by hatching them from eggs.

The institute, based in Minami-Ise, Mie Prefecture, succeeded in complete culturing of the eels in 2010. At present, however, only a small number are able to grow to the size necessary for shipment.

The Mie prefectural government’s Fisheries Research Institute succeeded in raising Japanese spiny lobsters from eggs to babies in 1988. However, researchers are still struggling with ways to deal with diseases that prey on the lobsters.

By KAZUKI NOBUHARA / Staff Write