Travel Esteros del Iberá, Argentina

What to see, what to do ?

Geography of Esteros del Iberá

Covering 13,000 sq km and located in the province of Corrientes, the Iberá Wetlands are one of the most fascinating regions for wildlife safari enthusiasts and for lovers of virgin nature. Ponds and lagoons are constantly forming and reforming in the marsh vegetation according to the currents of the water, the red straw savanna, aquatic plants, interlaced roots, carob and palm trees forests. This rich ecosystem is protected by a Natural Provincial Reserve as part of the Ramsar Convention (an international treaty for the conservation and sustainable utilization of wetlands) and by NGOs.

The first scientific research on the area was carried out by the French Alcide d’Orbigny during his journey of exploration in South America at the beginning of the twentieth century. For years, the wetlands were threatened by commercial hunting and illegal animal trading, endangering several species including the yaguareté. The Province finally protected the region in 1983 in order to maintain its fragile ecosystem.

The most important wetlands in Argentina, the Esteros del Iberá are temporarily or permanently flooded, depending on the location. However, the water, the subtropical climate and the limited access to the site permitted the development and the preservation of this incredible ecosystem. Over 4,000 animal and plant species live here, which account for almost one third of the biodiversity of the country. The Iberá Wetlands are just as rich as the better-known Pantanal in Brazil. In the Guarani language, Iberá means “bright water.”

Fauna of Esteros del Iberá

With about 300 bird species, 85 species of mammals, 45 species of amphibians, and 35 species of reptiles, Esteros del Iberá are packed with fauna, especially aquatic animals. Among the most emblematic species are the swamp deer, the capybara and the caiman.

Réserve naturelle Iberá Mammals
– The black howler monkey: its howl carries for 3 miles; it lives in the trees, moves with its prehensile tail, is herbivorous and lives in groups under the authority of the eldest male.

– The maned wolf looks like a large fox; it has a long red beard; it covers long distances and hunts alone at night.


– The neotropical river otter is perfectly adapted to the lake system of the Wetlands where it can catch fish, shellfish and mollusks. However, it is a vulnerable and protected species.

– The pampa deer: only small groups survive due to hunting and the destruction of its natural habitat. It is a short-haired animal of medium height and eats buds and tiny plants. The males mark their territory by exuding a strong odor.

– The marsh deer: the largest South American cervidae, the marsh deer is 1.2m tall and its branched antlers alone measure 22 inches. It prefers eating at night in the foliage; a good swimmer, he can cross ponds.

– The capybara is the biggest rodent of the world and is emblematic of the Esteros del Iberá. It never moves far away from the water in which it bathes, hides, and from which it drinks. Adults measure 47 inches and weigh 110 pounds. They live in groups and have litters of one to seven babies.

– Giant anteaters have recently been introduced in the region. These mammals are toothless but have a long and fine snout and a sticky tongue to eat ants and termites. They had disappeared from the Iberá Wetlands and are endangered in Argentina.

Réserve naturelle Iberá Birds : A ornithological paradise, the Iberá Wetlands is the place to observe over 300 birds species including toucans and parrots as well as rheas, storks, egrets, wood storks, Jabirus, Muscovy Ducks and other ducks, eagles, hawks, owls, hummingbirds, green woodpeckers, belted kingfishers and more…

Réserve naturelle Iberá Butterflies : About 25 kinds of butterflies are listed in the Iberá Wetlands. Particularly photogenic, these insects get their beautiful colors from the pigments of their scales and the reflection of light. Notable species include the red-and-blue Diablito,the lemon-yellow Pierid of Cassia, the orange American Monarch with its white and black spots, the White Peacock, the red Anartia with white spots and others…

Réserve naturelle Iberá Reptiles

– The caiman: two species coexist in the lagoons; the broad-snouted caiman and the black caiman. The high position of its eyes allows it to swim without being noticed. It spends days in the sun. The females build a 3.2-foot diameter mound in the middle of which they lay 50 to 60 eggs. They cover them and watch them from a distance. After the period of incubation, from January to March, the eggs hatch giving birth to 2-inch babies. They feed themselves with insects and larva from the nest, and after a couple of days their mother takes them to the river.

– The yellow anaconda or curiyú is the biggest snake in Argentina: it can measure up to 10 feet. It uses its teeth to grab its prey before choking them with its robust body. It is a semi-aquatic snake.

– The ñacaniná or gigas is a quick and aggressive rat snake that feeds itself with rodents, fish and batrachians. When the prey is small, the giga bites it before swallowing. When it is bigger, it kills the prey by strangling it or drags it to the water to drown it.

– The yarará is a very venomous and dangerous viper whose size can reach 67 inches.

Réserve naturelle Iberá Batrachians : There are many toads, but most of all frogs and tree frogs of all sizes and colors in the Esteros.

Réserve naturelle Iberá Fishes:

– The piranha: this tiny carnivorous fish is one of the most emblematic animals of subtropical regions. Its population grew drastically with the decrease of the caimans that prey on them. It rarely attacks human beings.
– The dorado as well as the sábalo, the fresh water ray, the eel and the corvine are part of the edible species.

Flora of Esteros del Iberá

Circuit Iguaçu Hydrophyte Plants : Either floating or rooted, these plants grow in water. The notable ones include water lilies and other nympheacea, water hyacinths (eichhornia azurea), water lettuces (pistia stratiotes), papyrus, crotons, hibiscus, victorias reaching up to 6.5 feet of diameter and others… These plants are eaten and inhabited by numerous insects, fishes and birds. There are also two carnivorous plants: the drosera and the urticular. The first one is hairy and exudes substances that attract and glue insects and the second one captures its preys by suction.

Réserve naturelle Iberá Parasite Plants: The parasite plants depend on others to eat. They come from the cuscutaceae, scrophulariaceae, viscaceae (mistletoe), and laoranthaceae families.  

Réserve naturelle Iberá Epiphyte Plants: These plants also grow on others but unlike parasitic plants, they don’t feed on them. Esteros del Iberá’s epiphyte plants include the bromeliaceae, orchid, cactaceae and polypodiaceae families.

Oiseaux Esteros del Iberá Land Trees and Plants : On the reliefs, along the water and on the floating islands grow many species of plants and trees including the ceibo tree, whose flower is Argentina’s national flower (a red rooster’s comb.) There are also ombúes, guava trees, jacarandas and their beautiful blue flowers, carob trees, cacti, quebrachos, butias (Pindo Palm) and savanna’s weeds.

Gauchos and fishermen

The Esteros del Iberá is a land of gauchos. They look after the estancias’ cattle in vast pastures and endless skylines. They move the herds between the ponds and the lagoons seeking for dried lands.

The other inhabitants of the Esteros are the descendants of the Guarani. They live secluded on the islands of the swampland, rearing animals, cultivating lands and fishing. They no longer hunt because commercial hunting is now forbidden. They are the real experts of the swamplands and its animals. Today, they guide the travelers through the canals.

Wildlife safari photographic

The region has few inhabitants and little infrastructure. We recommend organizing animal safaris through an agency. One can find information about the ecosystem at the visitor center in the only village of the swampland, Colonia Carlos Pellegrini. Either for trekking the paths or going on boat excursions, you will need a professional guide to find animals in the meanders of the swamps, since wildlife, specially amphibians, is mainly nocturnal. At the end of the day, when the light is fading, at night or at dawn is the time when the fauna becomes alive. Don’t forget to wear long sleeves for insects bites and to bring binoculars and a good camera.

Fall is the rainy season, winter is mild, summer is hot and spring (from September to December) is the best season to visit Esteros del Iberá. The average annual temperature is 68°F.

How to get to Esteros del Iberá

Because the region is difficult to access, Argentina Excepción offers safaris in the Esteros del Iberá with private flights and accommodations.

Esteros del Iberá Iguazú  By plane : there are daily flights between Buenos Aires and Posadas. After that a-3½-to-6-hour drive (164 miles) to reach the Esteros. There are no regular flights to Mercedes, the nearest city.

Esteros del Iberá  By bus : you should estimate 9 hours between Buenos Aires and Mercedes (500 miles), then 4 hours by minibus to cover the 70 miles to the city of Colonia Carlos Pellegrini on a non-paved road.