CRUISE ships are being built bigger but with less draught so they can get more easily into ports and places where ships either could not reach previously or were not allowed to go.

Increasingly they are able to venture into environmentally delicate areas. For example, regular cruises are now available on the Amazon. The more isolated the destination, the more the marketing people seem to love to send their vessels there.

The Indian Ocean is another of the newer destinations being explored by cruise ships. The islands of Aldabra lie about 1,000 miles (1,609km) from the African coast and 725 miles from Mahé, the main island of the Seychelles. There are more giant tortoises living wild on the islands than there are in the Galapagos and Aldabra is the only place where many rare species now live. The coral reefs that surround these islands are said to be the most unpolluted and beautiful in the world.

The number of visitors is limited to only a few hundred a year in the spring and the autumn. Passengers are taken there in small rubber dinghies from the few cruise ships which, for the moment, anchor offshore.

Unsurprisingly, the ships and cruise companies that go to the islands make much of the fact that they have remained untouched for so long. But how long will Aldabra stay pristine?

Will passengers, who happily spend about £4,000 each on a “trip of a lifetime”, really make a difference to the poor people who live on other, slightly larger, islands or on the mainland? Or will the local people find that entrepreneurs from other, larger, more sophisticated places within striking distance simply move there to sell whatever the cruise ships demand?

And what about Antarctica? This vast continent is both incredibly cold and incredibly beautiful. Yet, in the Antarctic, summer temperatures can reach about 5C, compared with minus 70C in the winter. No wonder that cruise ships are based in the Arctic during summer and the Antarctic during our winter - the region’s summer. The ice sheet covers more than 98 per cent of the continent, stretching over an area twice the size of Australia.

Dozens of cruise ships visit the mysterious, beautiful continent and - as anybody who has seen Sir David Attenborough’s documentaries on the wildlife of the region knows - it is also home to some of the world’s most fascinating creatures. So maybe we should all go. But maybe we should leave the creatures we see on our television screens to enjoy the solitude of the world extending from South Georgia southwards. Should cruise passengers really crane their necks and cameras to see a pod of killer whales?

More contentiously, should scientists spend months at a time in the last remaining wilderness studying temperature change, wildlife and the impact that we all make on this most remote part of the world? Should we really be “educating” the rich and the older cruise ship passenger, who still make up the majority of holidaymakers afloat, when we really should be concentrating on the younger generation?

It is a far from simple argument, but one that every passenger should at least consider before he or she sets off for some remote and possibly endangered part of the world.

Endangered destinations

CRUISING has never been more popular. Last year more than 1.2 million British passengers spent £1.55 billion on cruises. This was an increase of 12 per cent in passengers and 16 per cent in revenue over the previous year, Harvey Elliott writes.

Smaller ships - those with fewer than 1,100 passengers - carried 19,507 people last year, compared with only 6,684 in 1999. And many of those head for destinations such as the Antarctic, Alaska, the Galapagos Islands or other endangered parts of the world.

Galapagos Conservancy, for example, is concerned that ships such as the Discovery, with its payload of 500 or so passengers, are bringing in too many tourists.

It claims that flights to the islands have increased by 193 per cent since 2001 and wants all large ships to be prohibited from the area. It also claims that the population of the islands has more than doubled in the past decade.

Johannah Barry, president of Galapagos Conservancy, is worried about tourists “backing up” to trail round the islands. He says: “The whole idea is to swim and walk with the animals, not to line up with 50 other people to go on shore.”

But is it right that only a handful of biologists, scientists and other “experts” should have access to the most endangered areas?

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