Giant River Otter Spotted in Argentina for First Time in Decades

Last week, researchers spotted a giant river otter in the wilds of Argentina for the first time since the 1980s when the species was declared locally extinct, reports Graeme Green for the Guardian.

Giant river otters can reach six feet in length, weigh roughly 75 pounds and are among the top predators in the freshwater ecosystems they inhabit. They're found only in certain river systems of South America, including the Amazon and its tributaries, Orinoco and La Plata, according to National Geographic.

The individual spotted in Argentina was swimming along the Bermejo River, located in El Impenetrable National Park of the country’s Chaco province. Though they hung on in Argentina until the 1980s, these playful, intelligent fish-eaters hadn’t been seen in the Bermejo for more than a century, according to a statement by Fundacion Rewilding Argentina .

Sebastián Di Martino, director of conservation forthe organization, made the exceptional sighting while paddling down the river in a kayak.

“We grabbed the cell phone and started filming it, when he poked his body out of the water and showed the unmistakable white bib, we had no doubts, it was a giant river otter,” Di Martino tells Dharna Noor of Gizmodo via email. “We could not believe it, the record is incredible and how that specimen got here raises thousands of questions.”

A Giant River Otter seen in El Impenetrable National Park!
The @RewildingArg team spotted this otter, considered extinct in Argentina, in the Bermejo River, #Chaco Province. This great news brings new urgency to expand the Park to protect this species! #rewildingtheamericas pic.twitter.com/WT46vz39Wy

— Tompkins Conservation Global (@TompkinsRewild) May 24, 2021

Speaking with the Guardian, Di Martino says the endangered giant otter could have come from the Pantanal of Paraguay, which hosts the closest known population of the species and might connect with the Bermejo River some 600 miles away. He says it’s also possible that a tiny population survived in Argentina and has simply gone undetected until now.

This latter explanation is made somewhat harder to imagine by the fact that giant river otters tend to live in large, conspicuous groups, and this individual was seen swimming alone.

Conservation groups, which have been trying to reintroduce the species to Argentina’s waterways since 2018, are encouraged by the sighting because it suggests that the river system can still support giant otters.

Di Martino tells the Guardian that reestablishing giant otters in Argentina’s rivers could have a very positive effect on the local environment: “Giant river otters, as top predators, exert a regulatory influence in the aquatic ecosystem. It’s a regulator of fish populations, which contributes to the health of aquatic ecosystems.”

Conservationist and former outdoor apparel executive Kristine Tompkins, who along with her late husband Doug Tompkins founded Tompkins Conservation, wrote on Twitter that the sighting was “great news that adds urgency to the need to expand the park to protect this species!” Tompkins’ conservation organization helped create El Impenetrable National Park along with many others including Corcovado, Pumalin, Yendegaia, Kawésqar and Patagonia in Chile and Monte León and Iberá in Argentina. Altogether these national parks protect nearly 15 million acres along the southern tip of South America, Mongabay reports.

In light of this recent sighting, the statement indicates that local governments near the Bermejo River have reaffirmed their commitment to protecting the area from poaching, one of the threats that led the otters to decline in the first place.

According to the statement from Rewilding Argentina, three other giant otters in Argentina are currently being prepared for reintroduction to Iberá National Park near the city of Corrientes. Coincidentally, two of those captive otters, Coco and Alondra, just gave birth to three healthy pups, according to Mongabay. Rewilding Argentina now plans to release the family together once the pups have grown up a bit.

“These three cubs represent a future where human communities and the natural world can thrive together,” Tompkins tells Mongabay. “As we enter the [United Nations] Decade on Ecological Restoration, I strongly believe that our most urgent task is helping nature heal. Rewilding puts us on that path.”

Alex Fox | | READ MORE

Alex Fox is a freelance science journalist based in California. He has written for the New York Times, National Geographic, Science, Nature and other outlets. You can find him at Alexfoxscience.com.