Wildlife workers have stepped up their rescue mission in the face of a sudden surge in the number of birds and turtles coated with oil along the coastline of Louisiana, as the environmental impact of the Deepwater Horizon disaster visibly began to bite.

The number of animals being treated in the rescue centre in Fort Jackson doubled as a slick of oil reached sandy barrier islands off the coast that are nesting grounds for thousands of brown pelicans and terns. On Queen Bess island alone, 60 oiled birds, including 41 pelicans, were picked up.

Photographs showed pelicans and other birds immersed in dark brown goo, their feathers and in some cases even their eyes drenched.

Given the hundreds of thousands of barrels of oil that have already been spewed into the Gulf of Mexico since the crisis began on April 20, the visible environmental damage has so far been remarkably slight.

Favourable winds and currents, combined with the use of skimmer vessels, container booms and chemical dispersants to keep the oil away from land, have mitigated the impact.

But heavier quantities of oil are starting to reach land, with devastating consequences for wildlife. Florida has become the latest victim, with tar balls reaching the white-sand beaches of the Panhandle.

As visible signs of the calamity grew, BP engineers were racing to try to reduce the amount of oil gushing from the well.

Having cut the pipe on Thursday using giant shears manipulated by remotely controlled underwater devices, they embarked on the slow and difficult job of fixing a containment cap over the outlet designed to draw oil and gas up to the surface.

Thad Allen, the coastguard Admiral co-ordinating the crisis response on behalf of the government, said by Saturday morning about 1,000 barrels a day were being captured by the contraption. That compares with the latest estimate from government scientists that up to 19,000 barrels a day are spewing from the well.

The crisis is now dominating the White House agenda. President Barack Obama on Saturday cancelled a plan laid weeks ago to travel to Indonesia and Australia from June 13.

His Press Secretary Robert Gibbs said the President would remain in the U.S., “to deal with important issues, one of which is the oil spill”. — © Guardian Newspapers Limited, 2010

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