Japan : Purse-seining

Poor management, dwindling stocks

The traditional pole-and-line fishermen of Japan have been hit badly by the growth in purse-seining


This report is based on hearings compiled by Greenpeace Japan


Forty-five years ago the captain of a ship persuaded the Japanese government to import American technology to build Ski raw-i Maw, Japan’s first purse-seiner. Since then things have never been quite the same for Japan’s fisheries. Not only have stocks of diverse fish species dwindled, but Japan’s artisanal pole-and-line fishermen have also been put to immense misery.

Japan’s small-scale fishermen also use trolling and small gill nets to catch migratory species like mackerels, skipjack tunas, flying fish and squid as well as non-migratory species like alfonsino, bastard halibut and spiny lobster.

Traditionally, their fishery has been open for anyone to enter but some degree of self-regulation to control resources has existed. For instance, to protect the alfonsino fish during its breeding season, the fishermen themselves declare a four-month closed season.

No such compunctions bother purse-seiners. Usually, four to five of them make up a fleet which casts the net over 500 metres deep, catching a vast diversity of fish. About 80 per cent of tuna landings are by purse-seiners. A purse-seiner can catch over 400 tonnes of fish at one time. In contrast, small-scale vessels catch just 40 to 100 kg. pa day.

Purse-seining, which began in 1949, is a licensed activity allowed only in the three seas of the Northern Pacific, Central Japan and Western Japan.

In the beginning, Japanese purse-seiners operated only in the northern end of the Northern Pacific area to catch yellow-fin and skipjack tunas (1991 catch: 125, 000 tonnes). But once these stocks got depleted, they began moving southwards for mackerels and pilchards. This trend, which began around 1965, was a direct encroachment into the area and activity of small-scale fishermen. When it reached Chiba Prefecture in 1973, for instance, the competition completely wiped out pole-and-line fishing in a couple of years.

Many of the 2,000 small-scale fishing boats of Chiba were forced to idle as their catches were priced out of the market. This was because purse-seiners dumped large quantities of catch, pushing prices down.

Purse-seining has evidently led to indiscriminate overfishing. Purse-seiners operating in tropical waters are said to catch even juvenile skipjack tunas, each weighing under a kilogram and measuring less than 50 cm. long. (Large yellow-fin tunas are over 1.5 metres long). One indication of the drop in catches of mackerels, for instance, is the increasing amounts of imports from Norway of this once cheap and popular species.

Chasing stocks

A fisherman from Kochi Prefecture, traditionally a rich ground for pole-and-line fishing for skipjack tuna, told Greenpeace Japan, “When I first started working for a pole-and-line boat back in the 1960s, the catch was so good that you only had to operate from March to September in the offshore of Kochi, up to about 1,000 km to Hachijo Island south of Tokyo. One boat’s catch of 200 to 300 tonnes was enough to balance costs.

That is now history. “Today, he continued, “I start operating the boat in January, chase the stock as it moves, as far up as to the north of Hokkaido, which is more than 3,000 km. of travel, until December. Some among the 140 pole-and-line fishing boats can only catch 200 tonnes by operating all year.

The problem is compounded by the methods of fisheries management in Japan. These are diverse and range from fisheries co-operative associations regulating fishing rights, a registry system for boats and licensing for large-scale fisheries to the activities of the Sea Area Fisheries Co-ordination Committee.

Yet, in the absence of scientific estimates of even the major fish stocks in Japanese waters, these procedures mean little. Another obstacle is the compartmentalisalion among the various government fisheries agencies.

Official ignorance only aggravates the problem. According to Greenpeace Japan, one Fisheries Agency officer suggested to the small-scale alfonsino fishermen, “Why not let the purse-seiners operate during your closed season?

The failure to manage the fisheries has already led to open conflicts. In some prefectures, there have been demonstrations of 3,000 to 5,000 fishermen as well as the surrounding of a purse-seiner by 300 small boats protesting against its operation in their closed area.

In a letter of appeal last year to the Minister of Agriculture, Forestry and Fisheries, 120 small-scale fishermen from Kozushima Island, Tokyo proclaimed, “Most of the coastal fishermen are traditional fishermen, treating each fish with care, refraining from overfishing.

“We have chosen intentionally inefficient methods, the letter continued, “thankful for being allowed to take a part of the fish, hoping that enough is left for future generations.

That appears to be the only way out. The resolution adopted last year at Japan’s Festival for the Fertile Oceans emphatically expressed a similar sentiment. It declared that “the fertile oceans, which contribute to the basis of a nation’s life and culture, have to be protected and nurtured by the nation of the time and passed on to the future with pride.