Natural hype: Publicity push focuses on isolated corner of Argentina. (Executive Travel).

About 220 kilometers separate Colonia Carlos Pellegrini from the nearest gas station. Although there's little in the way of traffic, driving can still be treacherous as it involves dodging wildlife big and small, including caimans, bleach-white storks, rheas, snakes and mammoth-sized rodents called carpinchos. If this were the middle of Florida, grazing cattle, camera-clicking tourists and suburban homes would overrun these pristine wetlands. But this is Argentina, where decades of underdevelopment have left the marshy wetlands known as the Esteros del Ibera unspoiled.

Esteros de Ibera reign as the second-largest wetlands in the Americas, after Brazil's Pantanal. Despite the superlative, most people have never heard of them and barely 6,000 tourists each year make it to Carlos Pellegrini, population 800, to visit them. Even most residents of Buenos Aires, just nine hours by car from the natural jewel, are oblivious to the existence of the 13,000-square-kilometer natural sanctuary in Corrientes province.

That could all change. And soon. A much-deserved--and much debated--publicity boost is in the works courtesy of U.S. environmental activist and millionaire Douglas Tompkins, who courts controversy wherever he goes. In Chile, his ownership of Parque Pumalin, the world's largest private nature reserve, has peeved nationalist politicians in Santiago. It also irks energy companies and logging operations whose access to natural resources has been restricted by Tompkins.

Tompkins' plans for Corrientes are no less ambitious. During the past few years he has acquired 250,000 hectares of the Argentine wetlands, properties he plans to combine with a larger chunk of government-protected land to create what would be the country's largest national park.

"Doug is so low-profile that most people haven't realized the dimension of this project," says Alberto Ansolo, who sold his family farm to Tompkins then stayed on to work as the millionaire's local coordinator in Corrientes.

The thrust of Tompkins' activity is conservation, and a radical brand at that. Ibera, which mean brilliant waters in the native Guarani language, is one of the most biologically diverse habitats on the planet, with more than 350 bird species alone. As part of a 30-year management strategy, biologists employed by Tompkins plan to reintroduce species endangered by uncontrolled hunting. These include the giant river otter, pampa deer, giant anteater, talking parrot and, eventually, the jaguar.

As Tompkins knows from his experience in Chile, creating a national park can be a burdensome process and the one in the Esteros is still several years away. For now he's busy consolidating his own holdings. Still, if Tompkins prevails and a park debuts, it is expected to follow the strict standards set by Pumalin, where visitors are invited to interact with their surroundings--but not damage them. In Argentina's wetlands, the rules will be easier to enforce since the only way into the area is by boat.

Currently, Corrientes province restricts access to its portion of the wetlands, declared a provincial reserve, to four tourist boats a day. Each must have a guide. Tompkins is likely to duplicate such restrictions or impose other, equally tough, limits.

Building support. Tompkins is spending millions of dollars on this undertaking and presumably is banking on his network of environmental-activist buddies to join wildlife lovers in boosting tourism to the area. Work crews at Estancia El Socorro. Tompkins' hallmark property about 40 kilometers outside Carlos Pellegrini, are rushing to convert a century-old house into a rustic guest lodge in time for a scheduled mid-2003 opening. The lodge will sleep a couple dozen guests.

While Tompkins' foray into Chile sparked opposition, he's winning accolades in Carlos Pellegrini, which was already on its way to becoming an eco-village of sorts. Although the tourism infrastructure is incipient, two charming lodges cater to serious birdwatchers, scuba divers and nature lovers. But trickles of tourism have not been enough to combat the endemic poverty and 60% unemployment that plague the town. Tompkins plans to tap the knowledge of jobless farmhands and subsistence hunters when he recruits his future park rangers.

He's also benefiting from local residents' pride in the natural wonderland that surrounds them.

"Why wouldn't we love Tompkins?" asks Elsa Guiraldes, owner of the Posada de la Laguna, and head of a charity. Fundacion Acrapua, which assists needy children. "He's going to put Ibera on the map."

Name recognition is something people in Ibera desperately seek. As urgent as its economic needs may be, a poor town is better than no town at all. But that's exactly the fate that could soon befall Carlos Pellegrini unless an environmental calamity is sidestepped.

Last year, Paraguay and Argentina announced plans to boost production at the jointly owned Yacyreta dam, a stone's throw from the town. The dam, which for years has been the target of corruption charges, must hike its power output if it is to pay off its huge debt and, eventually, turn a profit. However, scientists say the planned diversion of the Parana River to allow for a 10-meter rise in the dam's water levels--and an increase in energy production--will disrupt the delicate ecological balance of the Ibera marshlands.

They fear flooding that could eventually put the wetlands--and the town of Carlos Pellegrini--under water "We could be looking at a real-life Atlantis down the road," says Marcelo Acerbi, project coordinator for Buenos Aires-based Fundacion Vida Silvestre Argentina.

Most of the opposition to the dam project comes from environmentalists in Buenos Aires, but there is a nascent eco-movement emerging in Carlos Pellegrini. Already Guiraldes and other residents adjacent to the wetlands complain of flooding, generating fears that the dam's operators may have prematurely augmented production.

Tompkins is well connected and his sphere of influence certainly reaches to the banks and multilateral lenders to whom Yacyreta is indebted. But what strategy this eco-warrior has in the works, he's keeping close to his chest. In the meantime, work moves forward on his park.