Sea birds rescued after they were contaminated with a colourless synthetic rubber are to be released back into the wild.
More than 300 birds, mainly guillemots but some razorbills, were taken into care by the RSPCA after being contaminated with Polyisobutylene (PIB) or butyl rubber.
They were rescued along the south coast shores at the end of January.
Tomorrow the birds will be taken to a cliff-top in the Portland area of Dorset, where most of them were found, and then released.
Peter Venn, manager at West Hatch rescue centre, said: "Our staff have done a fantastic job in cleaning and caring for these birds and now some of them are strong and fit enough to be released back to the wild where they belong."
Scientists have identified the glue-like substance which has been killing sea birds off the Dorset coast. Plymouth University say its used as an additive in lubricating oils to improve performance. Hundreds of guillemots have been washing on up on beaches along the south coast.
More than 300 are being treated at an RSPCA centre in Somerset. An investigation is underway into where the substance came from.
An RSPCA wildlife centre is working hard to help get hundreds of rescued birds contaminated with a mystery paraffin oil back to wild, while more calls are coming in about oiled birds turning up in Sussex.
More than 300 birds – mainly guillemots but some razorbills - were taken to the West Hatch centre in Taunton, Somerset last week after being contaminated with the strange substance described as ‘sticky Vaseline’.
The number of birds being found by RSPCA inspectors along the south coast, mainly around Dorset, has now dropped – but there is still a lot of work to do to ensure their care.
Tomorrow RSPCA inspectors in Sussex will be launching a boat from Littlehampton to check for more oiled birds after reports came in about an oiled swan on the River Adur and oiled guillemots.
It could be days before the true scale of the pollution spill affecting sea birds off our coastline is known. Wildlife experts say many more birds covered in a mystery sticky substance may have been blown out to sea.
So far, more than 250 birds have died, hundreds more have washed up on beaches as far as West Sussex and the Isle of Wight. Our Correspondent, Martin Dowse, sent this report from Dorset.
It could be days before the true scale of the pollution spill affecting sea birds on the south coast is known, wildlife experts said today.Read the full story ›
A change in wind direction could have killed thousands more birds after scores were found washed ashore along England's south coast.Read the full story ›
The number of birds being found dead on the South coast is continuing to rise. Most of the guillemots - which have been coming into the RSPCA centre since Tuesday - were washed up at Chesil Beach, near Portland - covered in a sticky substance.
But they've also been found in West Sussex, Hampshire and the Isle of Wight. Richard Lawrence has the latest.
If you're a "twitcher" or just interested in wildlife, you might know it's World Wetlands Day. It's to mark the anniversary of a treaty, signed by 164 countries, to protect important wetlands. But what does it mean for our region? David Johns explains, talking to Andy Daw of the RSPB.
Hundreds of seabirds have died after being covered in a "refined mineral-based oil mixture", with many of them found along the Sussex coast, the Environment Agency has said.
Almost 200 birds - mostly guillemots - are being treated at RSPCA centres along the southern coast after they were washed ashore covered in the white, sticky substance.
There was earlier speculation the mystery substance may have been palm oil, but scientists working to identify it have since reported that it is a refined mineral oil.
Staff took samples from the affected water in an effort to establish the cause of the pollution.
A spokesman for the Environment Agency said: "The results show that it is a refined mineral-based oil mixture, but not from an animal or vegetable-based oil, which rules out palm oil."
RSPCA deputy chief inspector John Pollock, who has been leading the rescue mission in Dorset, earlier described the substance as "white, odourless and globular".
He added: "It is like a silicone sealer. The best way I can think to describe it is 'sticky Vaseline'."
Staff at the RSPCA West Hatch centre near Taunton, Somerset, have been treating the birds using margarine and washing up liquid to clean the substance from their feathers.
Peter Venn, manager at West Hatch, said: "What we are hearing are reports of birds showing up on the Sussex coast, so that may mean that the weather is pushing them more easterly.
"This certainly adds up from the basis that we were getting birds earlier in the week from Cornwall, Devon, then up through Dorset and have had birds from Hampshire today, so everything is certainly not over by any means."
Wildlife experts are no closer this evening to discovering what the mystery substance is that has caused hundreds of sea birds to wash up on the south coast.
Most of the guillemots have been found at Chesil Beach in Dorset. But one bird has been found alive as far as Worthing in West Sussex - another, discovered on the Isle of Wight.
More than 100 of the birds have been taken to an RSPCA centre in Somerset as the Environment Agency investigates where the sticky substance has come from.
Martin Dowse speaks to RSPCA Insp John Pollock, volunteer Martin Usborne and Martin Cade from Portland Bird Observatory.