24 Jul 2019 Story Ecosystems and Biodiversity

Rewilding in Argentina: the giant river otter returns to Iberá park

Foto de Rafael Abuín/Conservation Land Trust Argentina

The first attempt to reintroduce an extinct mammal in Argentina brings hope for restored ecosystems and increased ecotourism opportunities based on wildlife watching.

In June 2018, two new jaguar cubs were born in northern Argentina’s new Iberá National Park, marking a milestone in the efforts to bring the species back into the region after decades of absence. Now steps are being taken to reintroduce the giant river otter (Pteronura brasiliensis) as well.

After an extended period in quarantine, Alondra, an eight-year-old female from Budapest Zoo in Hungary, has been reintroduced into the Iberá wetlands. For now, she is in a tailor-made enclosure of 800 square meters on the island of San Alonso in the province of Corrientes.

This is part of an ambitious rewilding project pioneered by the Conservation Land Trust of Argentina, the foundation created by Tompkins Conservation, in partnership with the province of Corrientes and thanks to the collaboration of diverse national entities.

Half on water and half on land: Alondra for the first time in her amphibian enclosure. Photo by Rafael Abuín/Conservation Land Trust Argentina

Along with illegal hunting and coastal development, the construction of large-scale dams contributed to the species' local extinction in the middle of the 20th century. Now the giant otter is globally endangered and extinct in Argentina, but in the few areas where the animal is currently found, including Brazil’s Pantanal and the Amazon region, it has become a key tourist attraction.

According to Kristine Tompkins, President of Tompkins Conservation and a United Nations Patron of Protected Areas, the arrival of the giant otters marks a significant step forward for the rewilding of the Iberá wetlands.  

“We are creating a model for rewilding that can be applied to areas around the world,” says Tompkins. “As a conservation foundation, all of our work is focused on strategies that fight the species extinction crisis that we face—from creating national parks to bringing back those species that have gone missing.”

Iberá National Park abuts a much larger (553,000 hectares) protected area, the Iberá Provincial Park, creating a huge contiguous swath of parkland centred on one of the largest freshwater wetlands in South America. The conjoined Iberá Park is the largest nature park in Argentina.

Picture taken by a drone shows the enclosure on the edge of the Paraná Lagoon, on the island of San Alonso. Photo by Rafael Abuín/Conservation Land Trust Argentina

Ideal conditions

Sebastián Di Martino, the Director of Conservation at the Conservation Land Trust of Argentina, says this huge protected area offers ideal conditions for the otter’s reintroduction and plans are under way to bring more giant river otters to the wetlands in order to reestablish the population.

“The project’s principal objective is for Iberá to continue to become whole and functional from an ecological perspective, especially now that the threats which had originally led the giant otter to extinction are no longer present,” he says.

Reaching up to 1.8 metres long, the giant otter is the largest aquatic mammal in the region and the longest otter in the world. Characterized by a flat tail and white throat, it is usually active during daytime, as well as territorial. Giant otters live in family groups of up to 15 individuals and subsist primarily on fish.

The rewilding project has long-term plans to continue until a healthy population of giant otters can re-establish itself in Argentina.

“This initiative from Tompkins Conservation, via their Argentine team, the Conservation Land Trust, is working to secure a future for threatened species,” says UN Environment’s Head of Wildlife, Doreen Robinson. “We are eager to learn from this rewilding project so that it can inform other activities. UN Environment will increase its focus on restoration in support of the UN Decade of Ecosystem Restoration 2021-2030 recently announced by the United Nations General Assembly," she adds.

Transporting Alondra by raft from the port of San Nicolás to San Alonso. Photo by Rafael Abuín/Conservation Land Trust Argentina

In December 2018, the Congress of Argentina passed legislation approving the creation of the nearly 160,000-hectare Iberá National Park, ensuring its long-term protection. Douglas and Kristine Tompkins, successful entrepreneurs from the United States, purchased the land through two foundations, Conservation Land Trust and Flora and Fauna Argentina, which ultimately donated the property to the public to become a national park.

The park not only has the first jaguar cubs in the region but is home to recovering populations of species that had been lost, including the giant anteater, the Pampas deer, the collared peccary and the red-and-green macaw.


For further information, please contact Lisa Rolls, Head of Wildlife Communication or Carolyn McCarthy, Global Communications, Tompkins Conservation