The new report confirms uncontrolled waves of violent, eco-damaging and illegal fishing activity worldwide, but with some of the biggest offences connected to the European market

Pirate fishing is out of control, depriving some the most world's most vulnerable communities of food and leading to ecological catastrophe, a three-year investigation has found.

"Illegal, unreported and unregulated (IUU) fishing is one of the most serious threats to the future of world fisheries. It is now occurring in virtually all fishing grounds from shallow coastal waters to deep oceans. It is believed to account for a significant proportion of the global catch and to be costing developing countries up to $15bn a year," says the report by the Environmental Justice Foundation.

Unscrupulous Chinese, European and Latin American companies, using flags of convenience, are operating illegal gear, fishing in sea areas they are not allowed and are not reporting their catches, the investigators found. In addition, ships are laundering illegally caught fish by transferring them at sea to legal boats making it impossible to identify catches.

The situation is particularly serious in African waters where pirate fishing may be now be taking nearly 30% of the catch from local fishermen. "IUU operators are stealing food from some of the poorest people in the world and are ruining the lives of local fishermen in countries like Somalia, Angola. These countries do not have the resources to police their territorial waters," says the report.

An aerial survey of Guinea's territorial waters found that 60% of the 2,313 ships spotted were committing offences. Surveys of Sierra Leone and Guinea Bissau waters found that levels of illegal fishing at 29% and 23%. An estimated 700 foreign-owned vessels are fishing regularly in Somalian waters for endangered tuna, shark and lobster.

"Heavily armed foreign vessels come close inshore and compete with small scale, artisan fishermen. They destroy their nets and traps and this has resulted in confrontations and loss of life," says the report.

Apart from the human misery that the pirate fishers are causing, the investigators found the practice undermining conservation measures, resulting in the depletion of fish stocks. Up to 75% of the world's fish stocks are fully exploited, over exploited or depleted according to the UN's Food and Agriculture organisation.

Rich countries police some oceans, but at great expense. In 2003, the Australian navy chased the Uruguayan-flagged Viarsa 1 trawler for 21 days across the Southern ocean. Its illegal catch of Patagonian toothfish was finally sold for over $1m.

But poor countries are helpless in the face of force used against them. Angolan fisheries authorities, says the report, have had their boats rammed and sunk by illegal trawlers, whilst other pirates have hurled buckets of boiling water on boarding parties. At least two inspectors have disappeared, believed murdered, while on observer duty aboard industrial trawlers.

The authors identify Las Palmas in the Canary islands as the centre of the illegal fishing trade in the Atlantic ocean. IUU vessels are allowed to land or tranship illegal catches which then enter Europe and the international market. The port only employs a handful of inspectors. "It is inexcusable that the Spanish government and the wider European authorities have failed to close Las Palmas," says the report.

It recommends that a global database of high seas fishing vessels is set up and that onboard observers, aerial patrols and more patrol vessels be used. But it acknowledges that countries need to put up hundreds of millions of pounds to stamp it out.

In a separate study, international marine group Oceana reported that European seas are among the most damaged in the world due to overfishing. "According to the European Commission, 88% of our fish stocks are overexploited. Of these, 69% are at risk of collapse. Each day in European waters more than 55,000 tonnes of oily and bilge waters and fuel waste are spilled into the sea, more than 350,000 hectares of the sea bed is impacted by trawlers and 20,000 tonnes of fish are taken out," says the report.

"Up to 3,000 tonnes of fish caught accidentally by fishing vessels in European waters is thrown back dead. Discards can reach 90% of the total weight of the catch in some fisheries," it adds.