By Alex Kirby
BBC News Online environment correspondent
Almost a year after she sank, the tanker Prestige is still polluting the picturesque coast of north-west Spain.
Victim of the spill: Dead guillemot (Image: WWF-Canon/Jorge Sierra)
Campaigners say thousands of tonnes of her cargo are floating offshore, and occasionally washing on to the beaches.
They say the oil spilt and the coast affected by the loss of the Prestige exceed the damage caused by the Exxon Valdez accident in Alaska in 1989.
The Prestige spill is estimated to have killed 300,000 seabirds, making it one of Europe's worst wildlife disasters.
The campaigners, from WWF, formerly known as the Worldwide Fund for Nature, accuse the Spanish Government of failing to clean up the coast of Galicia, the province worst affected by the spill.
In a report, The Prestige: One Year On, A Continuing Disaster, they say the tanker has spilt 64,000 tonnes of heavy fuel oil, 60% more than estimated at first.
The report says 5-10,000 tonnes are still floating offshore, with some reaching the coast from time to time - and 13,000 tonnes remain in the wreck.
The vessel sank on 19 November 2002, polluting about 3,000 kilometres (1,800 miles) of coastline.
The economic cost of the disaster to fishing and tourism is put at about 5bn euros (£3.4bn). The report criticises Spain for re-opening the fishing grounds too soon, and says some local fishermen's groups say their catches have fallen by 80%.
Oil on the Galician coast (Image: WWF-Canon/Raul Garcia)
Raul Garcia of WWF-Spain, the report's author, said: "If the Spanish Government continues to declare that the situation is under control, this looks like a cover-up rather than a clean-up.
"Until now, its management of the catastrophe has neither been driven by environmental criteria, nor has it been transparent."
Dr Simon Walmsley, a WWF marine pollution expert, said: "We need a fundamental change in the way the shipping industry is operated and regulated globally.
"Governments and the industry must meet their responsibilities to protect the environment by making sure substandard ships do not go to sea.
Fears for fishing
"Restricting tanker movements around sensitive marine areas, by designating them as Particularly Sensitive Sea Areas, will also mitigate the potentially disastrous impacts of oil spills."
The report says the large quantity of oil which sank to the sea bed in shallow water may release contaminants which will enter the food chain, including commercially caught species like sea bass, octopus, shrimps and crabs.
It also says the total investment in research into the Prestige spill will be less than 10m euros (£6.8m), which it compares unfavourably with the 270m euros ($310m) spent on research into the Exxon Valdez incident.
The clean-up goes on (Image: WWF-Canon/WWF-Spain/Elena Delgado)
The Alaskan spill affected 1,300 miles (2,100 km) of coastline and discharged 39,000 tonnes of crude oil into Prince William Sound.
The birds which were killed by the Prestige's cargo were mainly common guillemots, Atlantic puffins and razorbills.
The press counsellor at the Spanish Embassy in London, Fernando Villalba, told BBC News Online he was surprised by WWF's criticisms.
He said: "I'm from Galicia myself, and I was back there on holiday in August. The tourist numbers might have been a little bit down in July, but in August they were back to normal.
"The beaches were clean, though there may have been some oil on rocks below the water line.
"The government has made great efforts - it sent the army in to join the volunteers who were cleaning the coast, and there were up to 5,000 people involved every day for months on end.
"The Prestige isn't an issue in the Spanish media any more. I think perhaps WWF lacks knowledge of what's happened."