The Bermejo River flows through Impenetrable National Park in Argentina’s Chaco province. The secluded region had a special and surprising visitor last week in the form of a wild giant river otter. The otter, which was believed to be extinct in the country because of hunting and habitat loss, made an incredible reappearance right in front of Sebastián Di Martino, the director of conservation at Fundación Rewilding Argentina. The last time a wild giant otter was seen in Argentina was in the 1980s, and none have been seen on the Bermejo for over 100 years.
Di Martino was kayaking on the Bermejo when he spotted the incredible creature. “It reared up, so its white chest was visible, which I recognized as the giant river otter [Pteronura brasiliensis],” he reports. “At this point, your legs go weak, and your heart starts beating faster.”
Otters are integral to the balance of the eco-system, so much so that there were already plans in place to reintroduce them to the region. “Giant river otters, as top predators, exert a regulatory influence in the aquatic ecosystem,” Di Martino explains. “It’s a regulator of fish populations, which contributes to the health of aquatic ecosystems. It’s a spectacular animal, and it’s enormous; it can be 1.8 meters long. Adults weigh over 30 kg. They’re trusting and curious. To share the environment with them is marvelous.”
For over three years now, Rewilding Argentina has been working to restore the giant otter population in the Iberá wetlands, so the sighting of the one in Impenetrable National Park is uplifting news. Di Martino believes there are two explanations for how the giant otter ended up in the Bermejo. “The closest known populations of giant otters, which are endangered globally, are in the Paraguayan Pantanal, which could connect with this river from a distance of over 1,000 km,” which Di Martino explains is the simplest answer. “The other possibility is that there’s a remnant population of the species in Argentina that’s gone undetected. These animals live in family groups, and this was a solitary individual, which we think came from a group.”
Whatever the case may be, the reappearance of this wild giant otter supports the argument that if we protect wild and natural areas and promote rewilding, then animals will return. Di Martino hopes that the Bermejo River can be better protected, insisting that more supervision has to be implemented to curb the illegal hunting and fishing activity that runs rampant there.