The following apology was printed in the Guardian's Corrections and clarifications column, Saturday February 10 2007

In the report below we quoted environmentalists alleging that the British cruise liner MV Discovery was responsible for a rat, litter and graffiti found on the Galapagos islands after the liner's first visit last April. We have subsequently received letters from both the Galapagos National Park and The Darwin Foundation advising us that these allegations were incorrect. We now accept that the rat was observed before the Discovery's arrival and that a report by the Galapagos National Park Service did not link graffiti and litter with the Discovery. Voyages of Discovery would also like to make clear that passengers actually helped collect litter they found on the island. Apologies to MV Discovery and its passengers.





Not since Hamelin has the discovery of a rat provoked so much alarm. It was only a single creature, but it had no business being on the island of Santa Fe in the isolated Galápagos archipelago, where conservationists now strive to keep foreign wildlife at bay as effectively as hundreds of miles of open ocean did for millions of years.

The rat is alleged to have arrived on the MV Discovery, a giant British cruise liner that visited the islands in April. Today, the ship is due to return to the Galápagos, and arriving with it are 460 paying passengers, protests and a campaign to protect the islands from such mass tourism.

Voyages of Discovery, the cruise company, promises visitors to the islands: "The enigmas, secrets and charms of this spectacular and rich landscape are, like a dream, an unequalled adventure just waiting to be discovered." But to environmental campaigners, the ship's arrival is a nightmare. Conservationists on the Galápagos have also found swarms of foreign insects on the islands since the liner's last visit and fear its return today could introduce more alien species that might further disrupt the sensitive eco-systems.

The Discovery, the first large cruise ship to have visited the islands, is scheduled to return again this April and twice each year thereafter. Permits recently granted by the Ecuadorian government - the islands are owned by the South American country - could see one cruise ship stop there a month.

Leonor Stjepic, director of the Galápagos Conservation Trust, warned that such an acceleration in visitor numbers would overwhelm efforts to keep out pests and disease. "The more people that come, the greater the risk of invasive species and the less effective the quarantine system is going to be. With the best will in the world it's virtually impossible to search a boat that size thoroughly. Just sheer numbers means it's much easier for something to slip through. And if we can't protect the Galápagos then what does it say about the other natural spaces in the world?

"The Galápagos are not suitable for this kind of mass tourism. We're not being elitist: the islands just don't have the infrastructure for that number of people. We're not anti-tourism, but it's got to be high-value, low-volume tourism."

Before the Discovery's stopover, almost all visitors to the islands flew direct from the mainland. "This cruise ship has travelled all the way down the coast of South America and could bring all sorts of things with it," Ms Stjepic said.

As well as the rat, and the insects, environmentalists say the Discovery's previous visit left the islands covered in litter, dropped by wealthy tourists who "have no idea where they are or the impact their visit may have". Graffiti was scrawled at the visitor centre and one passenger reportedly asked where the local Starbucks was.

The study of the impact of the liner's first visit was carried out by the local Charles Darwin Foundation and the Galápagos National Park Service. As well as the foreign wildlife, it found that sales for local businesses increased by 5%, a third of what was expected. Infrastructure was overwhelmed, they said, and local tour operators, who take visitors around the different islands, were forced to land large boats on fragile shorelines because elderly cruise passengers were unable to scramble in and out of rubber dinghies.

However, David Yellow, managing director of Voyages of Discovery, said the campaigners were "speaking from ignorance". He said the firm operated under strict restrictions and carried out an in-depth environmental impact study before it was granted a licence to operate in the Galápagos. "We are experienced at operating in environmentally sensitive areas and we know what to do. All our people [passengers] are given a lecture before they go ashore and we know they adhere to it." The Discovery anchored at the island of San Cristobal during its stay, he said, a good 25 miles from Santa Fe where the rat was found.

Mr Yellow said there was no proof that the graffiti and litter were left by Discovery tourists. "Local people create litter. They are not as sensitive to the environment as the people we take there. There are local people who smoke a cigarette and throw it into the street."

Drawn by the unique wildlife and mystique, annual visitors to the archipelago have soared from about 40,000 in the late 1980s to more than 100,000 now.