An estimated €8 million worth of bluefin tuna exported from Maltese ranches has been blocked in Japanese warehouses since 2009.

The tuna, which amounts to some 800 tonnes, is actually part of a larger haul of 3,500 tonnes worth €40 million – mostly coming from Malta – which was blocked last year. But after talks between the EU and Japan, €32 million worth of tuna was released.

The figures are contained in a report drawn up by the International Consortium for Investigative Journalism (ICIJ) which carried out a seven-month investigation into the global trade of the prized fish.

The action in Japan, whose sushi market consumes 80 per cent of the world’s bluefin tuna, comes as officials in the east-Asian giant have started to “balk at the excesses of the ranching industry”.

According to the Rural Affairs Ministry, which is lobbying the European Commission to resolve the situation, the issue is a question of interpretation about numbers. It said that officials from the government and the EU were in ongoing negotiations with the Japanese Fisheries Authorities.

However, the ICIJ report, Looting of the Seas gives a different interpretation. “Among the problems Japanese inspectors found: ranch tuna were flattened at rates that were biologically impossible, and some ranches tried to export more fish than vessels had supplied to them.

“This is incomprehensible, no matter which way you look at it,” a high ranking Japanese official was quoted as saying in the report.

The investigation uncovered widespread abuses across the globe, alleging a $4 billion black market industry following “a decade of rampant fraud and lack of official oversight” by the EU authorities.

It points the finger mostly at French and Spanish fleets but the Maltese industry was not spared.

“I was a witness to the over-fishing and over-farming”, Emmanuel Delia, a professional diver for years with ranching companies, is quoted saying.

“There were no effective controls enforced on the bluefin industry before 2008.”

After 2008, “alarmed at the rate of bluefin decline”, regulators of the International Commission for the Conservation of Atlantic Tuna (ICCAT) came up with a new paper-based reporting system designed to help them better track the trade and deter the black market. But the system – dubbed the Bluefin Tuna Catch Document Scheme, or BDC – “is full of holes”, rendering the data almost useless, the ICIJ investigation found.

The report also highlights the extreme difficulty of enforcing quotas. “The (observers) complained it is almost impossible, standing on ship decks, to provide an accurate estimate of catches, according to an evaluation report commissioned by ICCAT,” the report said.

The investigation continues to pile pressure as EU member states squabble over whether to make further cuts to the bluefin tuna quotas ahead of a crucial ICCAT meeting which takes place in Paris this week.

The Maltese industry argues that further cuts in quotas could seriously jeopardise its future but it is already feeling the pinch from increased vigilance in Japan.

A spokesman for the Maltese industry said: “Maltese tuna ranchers are very distracted at the moment as they are facing severe cash flow problems.

“We are hoping that further talks between the EU and Japan take place in the coming days so that Maltese tuna can be released as soon as possible,” he said.

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