Thousands of birds have been covered in black oil leaking from the MSC Napoli, which was beached off the Devon coast.

The crowds who had excitedly combed beaches for the washed-up cargo of motorbikes,carpets, women's shoes and nappies were accused of increasing the long-term negative environmental impact to the Jurassic coast, a Unesco World Heritage Site.

But the impact of the 200 tonnes of oil that formed a five-mile slick on wildlife is already apparent and environmentalists have warned that the breeding population of the guillemot, which has nesting colonies along the Portland cliffs in Dorset, will be threatened. More than 900 guillemots and 200 gulls have been washed ashore covered in the tar-like oil from the vessel; these figures may triple as other birds are recovered over a 100-mile stretch of coast between Torquay and Portland Bill, warned Graham Madge, the spokesman on marine issues for the Royal Society for Protection of Birds. Three dolphins were also found dead, two at Chesil Cove in Portland and one 70 miles from the MSC Napoli at Swanage. Hundreds of dead fish, including pollack, whiting and conger eels, were found along the shore of Lyme Bay. Chesil beach, a Site of Special Scientific Interest, is covered in oil-coated debris.

The musician Billy Bragg, whose home borders Chesil beach, spent yesterday helping volunteers clear the detritus. He said: "There may have been bounty washed up in Devon, but here we have the real story: the story of selflessness, people volunteering to help out. I was so impressed. Although it will be a labour-intensive job it can be cleared if you put in a concerted effort. "This is not an environmental disaster. It is a hazard. The disaster we were dreading can be averted. I hope the people who have gone down to Branscombe beach to help themselves will stay for the clean-up." Bragg said he had feared a catastrophe when he first saw the debris.

" On Sunday night, a strong smell of petrol came off the sea. By Monday morning, the beach was strewn with debris black with oil. From here for 20 miles up to Portland the beach was devastated by the oil. People were down on the beach at first light rescuing the birds. A lot of people are deeply concerned about the wildlife."

The RSPB said that the oil affects the waterproofing of birds, so guillemots that are being dragged out to sea by northerly winds will be unable to dive or feed. Survival rates for recovered birds are low. Bragg's godson, James MacDonald, 18, is staying with the musician as part of a gap year.

"I wake up every morning to natural beauty, and suddenly everything smells of diesel," he said. "The detritus washed up from the ship is covered in thick oil ­ when you first look it is almost too much to take in." The 62,000-tonne MSC Napoli, carrying 2,394 containers ­ including 165 with hazardous chemicals ­ as well as 3,500 tonnes of heavy fuel had to be deliberately run aground near Sidmouth, Devon, last week when it developed a severe structural failure. The coastguard said that it had lost 200 tonnes of oil from its engine rooms as well as 103 containers, 76 of which have been retrieved.

Yesterday divers plugged a vent after heavy fuel began to leak while coastguards warned the clear-up operation, including removing the ship, could take a year. Officials also described the behaviour of scavengers who descended upon Branscombe beach to pick over the wreckage as "despicable". Access was barred to the beach yesterday. Many scavengers, the police said, appeared to have no intention of honouring their legal duty to inform the Receiver of Wreck within 28 days.


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