Esteros del Iberá

Esteros del Iberá

Yacare at Esteros del Iberá

Argentina’s biggest unsung attraction, Esteros del Iberá is a breathtaking wetland covering up to 13,000 square kilometers (estimates vary), nearly 15 percent of Corrientes Province. Recharged almost exclusively by rainwater, it’s really a broad, shallow river, covered by semisubmerged marsh grasses, reeds, and other water-loving plants; it flows diagonally but almost imperceptibly from the northeast toward the southwest, where the Río Corrientes enters the middle Paraná. There are also, however, open-water stretches like Laguna Iberá, a 24,550-hectare lagoon that’s protected under the Ramsar convention on wetlands of international importance.

In terms of wildlife, Iberá is an American Serengeti—while it may lack the total biomass of Africa’s famous plain, the variety of species and the sheer numbers of birds, mammals and reptiles is still awesome. For these reasons, it has attracted the attention of international conservationists such as former Esprit clothing magnate Douglas Tompkins, who has purchased several estancias in the area in the hopes of preserving their natural wealth.

And Iberá needs defenders, as the marshes have a fragile ecology imperiled by mega-hydroelectric developments of the Yacyretá dam, north of the city of Ituzaingó. As runoff from Yacyretá’s rising reservoir seeps into Iberá, deepening waters threaten to break the link between the marsh vegetation and the dissolved sediments from which the plants derive their nutrients.

Esteros del Iberá stretches over an enormous area, but the most convenient access point is Colonia Pellegrini, a placid hamlet of wide dirt roads on a peninsula jutting into Laguna Iberá, 107 kilometers northeast of Mercedes via RP 40. While Pellegrini has no formal street addresses, it’s small and compact enough that orientation is no problem.

Passable under most conditions though sections of it are bumpy, RP 40 can be muddy and difficult for conventional vehicles in very wet weather. It requires caution and moderate speeds at all times.

Sunset at Esteros del Iberá

Yacare Family

Carpincho or Capibará

Marsh Deer

Flora and Fauna:

Iberá’s flora and fauna make it a wonderland of biodiversity. Scattered open-water lagoons lie within an endless horizon of marshland grasses, aquatic plants, and embalsados (“floating islands”), which some ecologists have compared to tropical peat bogs. Even relatively large trees like the seibo (Erythrina cristagalli) and laurel (Nectandra falcifolia) flourish here and in gallery forests along faster-flowing waters.

Biologists have catalogued over 40 species of mammals, 35 species of amphibians, 80 species of fish, and 250–300 species of birds. The most readily seen mammals are the carpincho (capybara, Hydrochaerus hydrochaeris), marsh deer (Blastoceros dichotomus), and pampas deer (Ozotocerus bezoarticus; the mono carayá (Alouatta caraya, howler monkey) is more easily heard than seen. Less easily seen are the lobito de río (Paraná otter, Lontra longicaudis) and the largely nocturnal aguará guazú (maned wolf, Chrysocyon brachyurus).

Among the reptiles, there are two species of caimans, the yacaré overo (Caiman latirostris) and the yacaré negro (Caiman yacare). Australians, take note: these skinny, meter-plus creatures are not the massive crocodiles of Queensland and the Northern Territory, and will not pounce out of the swamps in search of human nourishment. The endangered water curiyú (water boa, Eunectes notaeus) is also present.

Birds are far too numerous to mention more than a sample, but the signature species include the chajá (horned screamer, Chauna torquata), mbiguá común (olive cormorant, Phalacrocorax olivaceus), several species of storks, herons, and egrets, and many waterfowl, including the endangered pato crestudo (comb duck, Sarkidiornis melanotos).

Sights and Activities:

Iberá is a year-round destination, but the summer months can be brutally hot and humid, and rain can fall at any time of year. Activities include bird-watching and other wildlife watching, hiking on a gallery-forest nature trail, and horseback riding.

Launch tours on Laguna Iberá, which involve poling through floating islands where an outboard motor is useless, are available through all the hotels, and private guides as well. One-hour excursions, on which it’s possible to see a lot, begin in the US$15 range for one person, US$7–8 for each additional person. As some animals are nocturnal, nighttime tours are also available, especially under the full moon.

Rental canoes and kayaks are available on Laguna Iberá, but kayaks in particular are unsuitable for exploring the marshes, whose dense vegetation makes visibility poor—there are few landmarks in this nearly featureless terrain and, in any event, you can’t stand up in a kayak to get your bearings.