Temps de lecture :3 minutes
Something weird is happening in the wilderness. The animals are becoming restless. Polar bears and penguins, dolphins and dingoes, even birds in the rainforest are becoming stressed. They are losing weight, with some dying as a result. The cause is a pursuit intended to have the opposite effect: ecotourism.
The massive growth of the ecotourist industry has biologists worried. Evidence is growing that many animals do not react well to tourists in their backyard. The immediate effects can be subtle – changes to an animal’s heart rate, physiology, stress hormone levels and social behaviour, for example – but in the long term the impact tourists are having could endanger the survival of the very wildlife they want to see.
Ecotourism has clear benefits. Poor countries that are rich in biodiversity benefit from the money tourists bring in, supposedly without damaging the environment. “Ecotourism is an alternative activity to overuse of natural resources,” says Geoffrey Howard of the East Africa office of IUCN (the World Conservation Union) in Nairobi, Kenya.
“Many of our projects encourage ecotourism so that rural people can make a living out of something apart from using too much of the forests or fisheries or wetlands.“
But while the IUCN and other organisations, and governments of nations such as New Zealand and Australia, try to ensure that their projects are ecologically viable, many ecotourist projects are unaudited, unaccredited and merely hint they are based on environmentally friendly policies and operations. The guidelines that do exist mostly address the obvious issues such as changes in land use, cutting down trees, making tracks, or scaring wildlife.
What is not considered are less obvious impacts. “Transmission of disease to wildlife, or subtle changes to wildlife health through disturbance of daily routines or increased stress levels, while not apparent to a casual observer, may translate to lowered survival and breeding,” says Philip Seddon of the University of Otago in Dunedin, New Zealand.
[…] Land animals are affected too. Since the early 1980s, specialised vehicles have been taking people to watch polar bears during October and November in Manitoba, Canada, a time when the animals should be resting and waiting for Hudson Bay to freeze over so they can start hunting seals. But often the bears are not resting as they should.
Markus Dyck and Richard Baydack of the University of Manitoba, Winnipeg, have found that signs of vigilance among male bears increased nearly sevenfold when vehicles were around. Just one vehicle could disturb the bears (Biological Conservation, vol 116, p 343).
Like dolphins, the bears may pay a heavy price for such altered behaviour. The tourist visits could be increasing the animals’ heart rates and metabolism when they ought to be conserving their energy, and this could be reducing their body fat and individual fitness, the researchers argue. “For slow-breeding animals the effects could take years to detect, by which time it may be too late to reverse the damage,” says Constantine.
[…] These findings undermine the premise that ecotourism is an ecologically sustainable activity. And it can have a damaging effect even in regulated tourist areas. In Australia, nearly 350,000 tourists a year visit Fraser Island off the Queensland coast, many hoping to see the island’s dingoes.
But in April 2001, after two dingoes attacked and killed a 9-year-old boy, the authorities culled 31 of the dogs in an effort to prevent further attacks (Tourism Management, vol 24, p 699).
Ecotourism can have an even more detrimental effect in the wilderness regions of Africa and South America. “In more remote places such as the Amazon, there’s not much control,” says ecologist Martin Wikelski of Princeton University in New Jersey.
Ecotourism is growing at a stunning 10 to 30 per cent per year, and now accounts for around one in five tourists worldwide. Whale watching – a category that also covers other cetaceans such as dolphins and porpoises – has become a billion-dollar industry. By 1998 it was attracting nearly nine million people a year in 87 nations and territories, compared with fewer than half a million 20 years earlier (see graph).
When ecotourism is done right, it can work. Wikelski points to the carefully controlled tourism of the Galapagos Islands, which brings in money for conservation and preservation of species such as marine iguanas. “Ecotourism is one of the main factors keeping the Galapagos safe,” he says.
In a study of levels of the stress hormone corticosterone in marine iguanas in the Galapagos, Wikelski found that the reptiles are not stressed by humans. “They have apparently completely adapted to the fact that the people are there,” he says. “At least, that is one interpretation. We also don’t see any survival problems.”
[…] Biologists are now calling for such studies before ecotourism projects are started. “Pre-tourism data should always be collected, where possible,” Constantine says. Nature-based tourism needs to be developed cautiously, hand in hand with research, she adds. “The animals’ welfare should be paramount because without them there will be no ecotourism.“
New scientist, 04 March 2004.
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