Good gone wild: sometimes, ecotourism hurts what it sets out to help

Science News,  Sept 30, 2006  by Eric Jaffe

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The island of Damas is a half-hour boat ride from the Chilean coast. On the island, it's dry and rocky. The Humboldt penguins that live there have no ice slopes to slide down in their blacktie apparel. Instead, these desert penguins seek out caves to shade their eggs from the sun. If they can't find a spot beneath a boulder, they may burrow into seabird dung. Sometimes, they nest inside a cactus.

To see these penguins, visitors usually begin in La Serena, Chile. They drive 40 miles north on a main highway and then cut toward the coast on a gravel road that leads to the fishing village of Punta de Choros. Local fishermen there charge a fee to guide the tourists to Damas by boat. On the island, people are free to walk into the caves where the penguins live. Anyone can watch a mother brooding an egg and snap a picture with a flash camera or a mobile phone.

What began in the early 1990s as a place with a few hundred curious visitors has now become a tourism destination that attracts 10,000 penguin peepers a year. Damas provides an example of ecotourism, defined as the practice of visiting sites where exotic landscapes and rare animals are the main attractions. Ideally, ecotourists learn about the habitats that they visit, provide donations to conserve them, and generate income for host communities.

Since this model of tourism emerged some 25 years ago, many special-interest sites, like Damas, have experienced hikes in visitation. Often, ecotourism is a wild success (SN: 12/3/05, p. 364). The United Nations even billed 2002 the "International Year of Ecotourism."

But several recent studies show a more complicated picture of the impact of ecotourism, a practice that remains largely unregulated. The increased crowds lead to population changes in some animals, such as the Humboldt penguin and, some 4,000 miles away in the Bahamas, the Allen Cays rock iguana. A mounting garbage problem caused by over-visitation by turtle viewers threatens the beaches of Tortuguero in Costa Rica. People who live near Ghana's Kakum National Park have lost access to the forest's resources and now suffer high rates of unemployment.

"There comes a time when you have so much interference through ecotourism that you affect the thing you're trying to protect," says Robert E. Hueter of the Mote Marine Laboratory in Sarasota, Fla., who studies ecotourism's impact on whale sharks. Ecotourism's benefits to conservation and public education are considerable, he says, but the downsides may take a long time to recognize.

"I think there's been a glib ... championing of ecotourism, that it's a win-win situation," says Martha Honey, executive director of the Center on Ecotourism and Sustainable Development in Washington, D.C. But by studying how animals, environments, and cultures respond to ecotourism, "we can set up systems that aren't having adverse impacts," she says.

FLIGHT OF THE PENGUINS Ursula Ellenberg decided to study how human disturbance affects the Humboldt penguins when she was quietly counting their population, but not quietly enough. While she was looking through binoculars from a cliff about 150 meters away, the penguins began racing in all directions. One of the penguins had spotted Ellenberg, despite her unobtrusive perch. If a cautious researcher can spark such a reaction, she thought, how would the penguins react to a gaggle of shutter-happy tourists?

To study the effects of human-Humboldt interaction, Ellenberg and her colleagues measured the breeding success of penguins on the islands of Damas, Choros, and Chanaral, which together make up the Humboldt Penguin National Reserve. The island cluster serves as a good point of comparison: Damas receives 10,000 annual visitors, but Choros and Chanaral are much less accessible from the mainland and attract only 1,000 and 100 tourists a year, respectively.

Ellenberg's team was the first to study these penguin populations. The researchers monitored eggs and chicks on each island for 5 months after the penguin mothers laid the eggs. If a nest is abandoned during this period, the chicks usually die. Penguins have many chances to breed during their 20-year life spans, and they would sooner abandon a nest than risk personal harm--say, from an approaching human.

In 2003, the only year that Ellenberg's group studied Chanaral, the penguins there bred an average of 1.34 chicks. On Choros, the average was just below one chick in both 2002 and 2003. But on Damas, female penguins produced, on average, a little less than half a chick in 2002, and the birthrate dipped well below a quarter of a chick in 2003, Ellenberg's team reports online and in the November Biological Conservation.

"It's surprising, when you have islands at such close proximity, that you'd already get a difference," says Ellenberg, a biologist at the University of Otago in New Zealand. "They should do similarly well."

Working in the Bahamas, John Iverson of Earlham College in Richmond, Ind., has discovered similarly detrimental effects of human presence on Allen Cays rock iguanas, an endangered species.