More than 20 million people employed in the fishing industry may need to be retrained for other work over the next 40 years if the final collapse of fish stocks in the world's oceans is to be avoided, the U.N. warned on Monday.

The U.N.'s environment branch, UNEP, gave a preview of its green economy report that will be published in October. It said if the world remained on its path of overfishing, by 2050 fish stocks could become uneconomic to exploit, or extinct.

Pavan Sukhdev, head of the initiative, said: “Already 30 per cent of the ocean fisheries have collapsed and are producing less than 10 per cent of their original ability.” At the heart of the analysis is the $27 billion in subsidies it estimates is being injected into fishing every year, mainly by developing countries. The U.N. says the subsidies are huge in terms of the scale of the industry, amounting to almost a third of the $85-billion total value of fish caught.

Among those subsidies, the U.N. defines $8 billion as “good”, in that they encourage sustainable fishing of healthy stocks. Most of the subsidies are “bad”, meaning they lead to overcapacity and exploitation, and about $3 billion of the subsidies are “ugly”, leading to the depletion of fish populations.

Among the most egregious practices targeted by the report are inducements to boost the size of trawler fleets that are among the main culprits of overfishing, and subsidies on fuel for fleets. “We're paying ourselves to destroy the very resource on which the fishing industry is dependant,” said UNEP director Achim Steiner.

At stake is not just the biodiversity of the oceans, but a substantial chunk of the global economy and the livelihoods that depend on it.

The U.N. estimates there are 35 million people directly employed in fishing, which translates to about 120 million including their households, and 500 million — or about eight per cent of global population — taking into account indirect businesses such as packaging and freezing.

The report is being prepared prior to the Rio+20 summit in Brazil in 2012. UNEP refuses to name the worst offenders in overfishing, though it says its final report will contain figures that will enable readers to “figure out where the problem is”. — © Guardian Newspapers Limited, 2010

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