Tag Archives: aquaculture

The Survival of Red-Listed Bluefin

Japanese call bluefin tuna “the king of fish”. They eat about 40,000 tonnes of it a year—80% of the global catch. Demand is also growing rapidly elsewhere. Yet Pacific bluefin stocks are down by 97% from their peak in the early 1960s, according to a recent report from the International Scientific Committee, an intergovernmental panel of experts. (Japan disputes its findings.) In some places, fishing is three times the sustainable level, the committee says.

Aquaculture might seem to offer a way out of this impasse. But the bluefin is hard to breed in captivity. In the open sea, it can roam for thousands of miles and grow to over 400kg. It is highly sensitive to light, temperature and noise. Early attempts to farm it fizzled, but Kindai University persisted long after an initial research grant from the government ran out in the early 1970s. In 2002, funding itself from sales of other fish, it managed to rear adult tuna from eggs for the first time, rather than simply fattening up juveniles caught at sea. Now the chefs in Ginza can have a tuna zapped with an electric prod and yanked out of the university’s tanks on demand.

However, just 1% of the bluefin the university rears survive to adulthood. “We expect this to improve but it will take time,” predicts Shukei Masuma, the director of its Aquaculture Research Institute. Worse, the tuna gobble up lots of wild mackerel and squid. Scientists have experimented with soy-based meal and other alternatives. A company in south-western Japan said this month that it had managed to raise tuna using feed made of fishmeal, but it is costly and the fish are slow to thrive. Using wild fish for feed makes bluefin farming unsustainable, says Atsushi Ishii of Tohoku University. He sees aquaculture as a distraction from the thorny task of managing fisheries properly.

This debate is slowly seeping into the public consciousness. In 2014 the media made much of the decision of the International Union for Conservation of Nature, a conservation body, to put bluefin tuna on its “red list” of species threatened with extinction.

Excerpts from The Japanese Addiction to Tuna: Breeding Bluefin, Economist, Sept 24, 2016

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Fishing to Death

Fishing vessel. image from wikipedia

Under international law the high seas, which span 64% of the surface of the ocean, are defined as “the common heritage of mankind”. This definition might have provided enough protection if the high seas were still beyond mankind’s reach. But the arrival of better trawlers and whizzier mapping capabilities over the past six decades has ushered in a fishing free-for-all. Hauls from the high seas are worth $16 billion annually. Deprived of a chance to replenish themselves, stocks everywhere pay the price: almost 90% are fished either to sustainable limits or beyond. And high-seas fishing greatly disturbs the sea bed: the nets of bottom trawlers can shift boulders weighing as much as 25 tonnes….

A fresh approach is needed. Slashing fishing subsidies is the most urgent step. In total these come to $30 billion a year, 70% of which are doled out by richer countries. By reducing fuel costs, subsidies bring the high seas within reach for a few lucky trawlers, largely from the developed world. Just ten countries, including America, France and Spain, received the bulk of the bounty from high-seas catches between 2000 and 2010, even though Africa has more fishermen than Europe and the Americas combined. That is unfair and short-sighted.

The next step is to close off more areas to fishing. As of 2014 less than 1% of the high seas enjoyed a degree of legal protection. A review of 144 studies published since 1994 suggests that to preserve and restore ecosystems, 30% of the oceans should be designated as “marine protected areas” (MPAs). Individual countries can play their part, by creating reserves within territorial waters: last year Britain created the world’s largest MPA, an area bigger than California off the Pitcairn Islands in the South Pacific. But to get anywhere near that 30% share, mechanisms must be found to close off bits of the high seas, too. The UN’s members have rightly agreed to work out how to do so…

So in parallel with efforts to protect wild stocks, another push is needed: to encourage the development of aquaculture, the controlled farming of fish. In 2014, for the first time, more fish were farmed for human consumption than were caught in the wild; farmed-fish output now outstrips global beef production. Unfortunately, feedstocks are often poor and storage facilities inadequate. …Eventually, efficient fish-farming will be the best guardian of stocks on the high seas.

Marine Management: Net Positive,  Economist, July  16, 2016, at 13

Damaged Fish For Sale

fishing

The global fish-price index of the UN’s Food and Agricultural Organisation (FAO) hit a record high in May 2013.  High oil prices, which increase the cost of fishing and transportation, also add to the price of putting fish on the table.  Not all fish are created equal, however. There are two types of fish production: “capture” (or wild) and “aquaculture” (or farmed). And they seem to be on different trajectories. Fish such as tuna, the majority of which is caught wild, saw much bigger price increases than salmon, which are easier to farm. Overall, the FAO’s price index for wild fish nearly doubled between 1990 and 2012, whereas the one for farmed fish rose by only a fifth. What explains this big difference?

The amount of wild fish captured globally has barely changed in the past two decades. The ceiling, of about 90m tonnes a year, seems to have been reached at the end of the 1980s. Overfishing is one reason, as is the limited room for productivity growth, particularly if consumers want high quality.

Patrice Guillotreau of the University of Nantes tells the story of a fleet in France that decided to trawl, rather than line-catch, its tuna. It brought more back to shore, but the fish were damaged. It could not be sold as high-value fillets and was only good for canning. The old ways of catching fish are still best if you want the highest profits, says Mr Guillotreau.

In contrast, the farmed-fish industry continues to make productivity improvements. Fish farms have found crafty ways to use lower quantities of fishmeal as feed. In the early days of aquaculture, it could take up to ten pounds of wild fish to produce one pound of salmon. Now the number is down to five. That may still be an inefficient use of protein, but the ratio is set to improve further. Fish farms have also become more energy-efficient, meaning that they are less affected by higher energy prices. And they have learned how to handle diseases better, reducing the quantity of fish that ends up being unsellable.  As a result of all these improvements, the global production of farmed fish, measured in tonnes, now exceeds the production of beef. Output is likely to continue growing: the FAO estimates that by 2020 it will reach six times its 1990 level.

This growth will further shake up the markets for fish. The farmed kind is expected to dominate the market for medium-value produce. Suppliers of wild fish, for their part, must slither into niche markets. At the low-value end wild sardine is a crucial input for farmed fish and is in abundant supply. More than a third of the total marine catch in 2010 was used for the production of fishmeal and fish oil.  But more money may be made serving the captains of industry rather than industry itself. Sapmer, a French fishing company, recently discontinued its canned-tuna production, instead concentrating on catching tuna for sushi and sashimi for the top end of the market.

Frank Asche of the University of Stavanger, who helped to devise the FAO fish-price index, sees parallels with the divergence between farmed meat and wild game. As the supply of wild fish declines relative to farmed fish, it will become a luxury commodity, he explains. “In 20 years’ time people will think of wild fish like we now think of venison.”

The price of fish: Different scales, Economist, Aug. 10, 2013, at 64