More than anywhere else on Earth, the polar regions are most affected by global warming. Yet it is exactly this threat to their existence that is attracting more tourists to the region than before.

The World Tourism Organisation puts the number of annual visitors to the Arctic, including Alaska, at more than one million. Although far fewer tourists visit Antarctica, the rate of there growth is causing as much concern to environmentalists.

This year 33,000 people will visit the Antarctic region, up from about 7,400 a decade ago, according to the International Association of Antarctic Tour Operators (IAATO), which promotes responsible tourism practices.

Scientists worry that this almost morbid curiosity with seeing the Earth’s last great frontier before it melts away will only hasten the regions’ deterioration.

“The growth in tourism has the potential to affect national research programmes and to increase the risk to the marine environment and terrestrial ecosystems,” says a report by the United Nations Environment Programme. But despite these concerns, it forecasts that visitor numbers will continue to climb as the sea ice in the region continues to retreat – opening up new passages for cruise ships.

Environmental researchers point to the Antarctic as an area of particular concern. Dr Alan Hemmings, a polar regions environmental consultant, says that whereas the Arctic is parcelled out to such nations as America and Canada, whose governments have the authority to regulate tourism in the region, no state or international laws govern tourism practices in the Antarctic.

Rather, supervision is handled through the Antarctic Treaty, which requires a unanimous decision by its member nations on any proposed tourism regulations.

Hemmings says: “Glacier Bay in Alaska has a long history of cruise liners breaching waste disposal and pollution laws, yet Alaska is subject to US maritime regulations. Imagine what could happen in Antarctica where there are no formalised regulations.”

Dr John Shears, of the British Antarctic Survey, says the Norwegian cruise ship which ran aground on Antarctica’s Deception Island earlier this year was “a big wake-up call” for everybody concerned, and made it clear that a more stringent supervision of tourism is urgently needed. This year Antarctic treaty members came extremely close to implementing a legally binding set of tourism regulations, but the measure failed to receive the necessary unanimous vote.

Instead, members agreed on a few key resolutions, which brought treaty members into line with existing IAATO by-laws. These include a specific limit on the number of visitors allowed ashore in the Antarctic and a ratio requirement of one guide for every 20 visitors.

Treaty members also agreed to cap the number of cruise vessels visiting an area of the Antarctic at any one time to 40 and to allow only one vessel at a time to land on a particular site.

Shears says that while these resolutions are a step in the right direction, they are not legally binding and only apply to treaty members. They are far from a real solution to the big issues of polar tourism.

“The big cruise liners are the main concern,” he says. This year an American-flagged Princess Cruises ship, weighing 109,000 tons, carried an excess of 3,000 people into the Antarctic Peninsula. That is 200 people more than the entire population of Antarctic stations at the height of summer.

Next year a Cyprus-flagged cruise liner, which is not party to the Antarctic Treaty, plans to land 1,200 people – more than twice the number sanctioned by treaty members.

Shears adds: “Many of these bigger ships are not ice-strengthened and the crews are not sufficiently trained to operate in this area. It is very dangerous and poses significant environmental threats.”

Denise Landau, executive director of IAATO, agrees that there are certain areas where ships should be ice-strengthened and that the experience of the captain and crew are important considerations. She dismisses the notion that more stringent measures would have a negative impact on its members.

“We have always supported responsible oversight of tourism but it is not up to IAATO, but rather countries under which the operators are flagged, to decide the rules.”

The double whammy of climate change and tourism

For millions of years the Antarctic has been cut off from the rest of the world by its remoteness, climate and the Southern Ocean’s mighty circumpolar current.

But its splendid isolation and that of its fragile ecosystems are now under unprecedented threat from the double whammy of climate change and a swelling flotilla of tourist cruise ships.

So far, few alien species have become established on Antarctica: just a few kinds of meadow grass, and a flightless midge on Signey Island. But Rachel Clarke, senior environmental manager with the British Antarctic Survey, says invasive alien species represent a “huge potential problem” for native ecosystems.

“Thanks to global warming and the increasing numbers of tourists, this is one of the greatest risks facing Antarctica – and is something we are working very hard to prevent.”

South Georgia is one example of the damage alien species can cause. Since it was first visited by whalers two centuries ago, more than 200 alien species have taken hold there including grasses, brown rats, inverterbates and reindeer.

The 1,300 reindeer have depleted indigenous flora, while the rats are voracious predators of sea bird eggs and chicks.

Rare birds such as burrowing petrels, blue petrels, South Georgia pintail, prions and the South Georgia pipit are now only found on rat-free offshore islands.

The International Association of Antarctic Tour Operators has imposed stringent biosafety protocols to keep out seeds and insects and these are generally respected. And from next month the 2004 Ballast Water Convention will require ships entering the region to take on fresh ballast water at the Antarctic Convergence.

However, significant threats remain from widespread fouling on ships’ hulls. This fouling can involve as many as 20 species, including some known to be invasive such as the Mediterranean mussel, which can survive Antarctic conditions.

Such findings led the 2006 Antarctic Treaty Consultative Meeting to warn that hull fouling may be “the most significant pathway for marine introductions”, while this year’s meeting resolved that research to reduce risks posed by hull fouling was “urgently required”. OLIVER TICKELL

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