At the booths around the conference hall, the discussions were of fatty fish, freezer technologies and the sashimi freebies. It was the kind of shoptalk you would expect at the Japan International Seafood Show, an annual three-day event held last week in Tokyo.
But off to one corner of the hall, a serious debate raged about the future of the industry. The topic that drew a standing-room-only crowd: farm-raising bluefin tuna. Eight years ago, researchers at Japan’s Kinki University grew bluefin from eggs in captivity – the first to do so. The breakthrough fuelled hopes for a solution to the overfishing that has pushed the bluefin to near extinction. By 2004, the university had shipped the first of its bluefin to market.
Last Thursday, the Kinki University team said they will soon be mass-producing bluefin from hatchlings. “We will be able to grow 40,000 to 50,000 fry every six months,” said Masahiko Ariji, a Kinki University professor. Ariji’s bold prediction: within five years, half of the bluefin eaten in Japan could be farm-raised, up from a mere 10 per cent now.
The caveat is, of course, that methods such as Kinki University’s must spread. Nearly all of the fish grown at farms in Japan are moved there after being netted at sea as youngsters. As more farms grow bluefin from eggs, they could become less dependent on populations of wild fish.
It’s no coincidence that Japan is leading the field. The country whose sushi restaurants made the bluefin tuna a delicacy consumes 70 per cent of the Atlantic and Mediterranean bluefin globally – about 43,000 tons in 2008, according to the Fisheries Agency.
So far efforts to protect the bluefin have foundered. WWF says overfishing and black-market exports continue despite international catch quotas. Some blame rising bluefin consumption in countries such as China and Singapore. Others point the finger at Japan, which imports half of what it consumes from countries, such as Mexico and Malta. Some imports are channelled through Asia, where quota enforcement is lax, says WWF.
It’s debatable whether Tokyo deserves the flak. Even so, Japan has done little to win sympathy. In March, Tokyo mobilised nations to defeat a proposed global trade ban on Atlantic bluefin tuna at the Convention on International Trade in Endangered Species (CITES) meeting in Qatar. To appease ban supporters, Japan is considering quotas to protect young bluefin, a shorter fishing season and rules on catch size reporting.
Farming isn’t without its share of critics. Sushi chefs complain that farmed tuna is excessively fatty because the fish don’t swim as much as they would in open seas. Environmentalists contend that fish farms pollute the ocean. Farms are also susceptible to bacteria and typhoons, researchers say. One new idea is to raise fish in tanks on land, using seawater pumped from deep beneath the earth’s surface and purifying the discharge. Nobuhiko Akiyama, a professor at Tokai University’s school of marine science and technology in Shizuoka, revealed earlier this month that it can be done with bluefin.
Japan is eager to open more domestic farms. But raising tuna in captivity can be tricky. The fish tend to cannibalise when young or die in shipping, so anyone who starts a farm needs cash, patience and a stomach for risk. The good news, says Kinki University’s Ariji, is that “farmed and wild bluefin now fetch comparable market prices.” With any luck, profits shouldn’t be far behind.