Extinct in Argentina, the Giant River Otter returns to Esteros de Iberá

Lobo gargantilla © Ramón Moller Jensen

The first giant river otters (Pteronura brasiliensis) have arrived to the Argentine province of Corrientes. The event is considered vital part of an ambitious rewilding project pioneered by CLT Argentina (Conservation Land Trust), the foundation created by Tompkins Conservation, in conjunction with the province of Corrientes, and the collaboration of diverse national entities. The arrival of Lobo, a four-year-old male from the Parken Zoo of Eskilstuna, Suecia, and Alondra, an eight-year-old female from the Budapest Zoo in Hungary, hails the return of the top aquatic predator to the Iberá wetlands.

Along with illegal hunting and coastal development, the construction of large-scale dams contributed to the species' extinction in the middle of the 20th century. In areas where the animal is currently found, including Brazil’s Pantanal and the Amazon region, the animal has become a key attraction for wildlife watching and conservation-based tourism.

Lobo gargantilla © Ramón Moller Jensen

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

The giant river otter is endangered in the majority of the countries countries where it is currently found. Sebastián Di Martino, the director of conservation of CLT Argentina, acknowledges that the huge protected area offered by the adjoining Iberá National Park and Iberá Provincial Park offers ideal conditions for its reintroduction. “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.”

Reaching up to 1.8 meters long, the giant otter is the largest aquatic mammal in the region and the longest otter worldwide. Characterized by a flat tail and white throat, they are usually active during daytime, as well as territorial. A social animal, giant otters live in family groups of up to fifteen individuals and subsist primarily on fish.

The process of adapting these animals to life in the wild will require an extended quarantine period with routine check ups in San Cayetano, Corrientes. The pair will gradually be introduced to each other before their release in the heart of the wetlands in San Alonso.

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

Last updated March 26, 2019

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