{"id":30062,"date":"2025-07-01T14:30:14","date_gmt":"2025-07-01T14:30:14","guid":{"rendered":"https:\/\/www.europesays.com\/us\/30062\/"},"modified":"2025-07-01T14:30:14","modified_gmt":"2025-07-01T14:30:14","slug":"giant-river-otters-return-to-argentina-after-40-year-absence","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/30062\/","title":{"rendered":"Giant river otters return to Argentina after 40-year absence"},"content":{"rendered":"

A family of four otters, including two pups born in captivity, have been set free in the Iber\u00e1 wetlands in north-east Argentina, the first step in reintroducing the species to its original habitat.<\/strong><\/p>\n

Endangered globally, the giant river otter<\/a> (Pteronura brasiliensis) has been absent in Argentina for over 40 years, after habitat loss and illegal hunting led to its decline.<\/p>\n

The milestone release is also the first time a top predator has been brought back from\u00a0nationwide\u00a0extinction in the country.\u00a0<\/p>\n

\"GiantGiant river otters can measure 1.8m in length. Credit: Matias Rebak, Rewilding Argentina<\/p>\n

Meet the world’s largest otter<\/p>\n

The project is a collaboration between the provincial government of Corrientes, Argentina\u2019s National Parks Administration, and\u00a0Rewilding Argentina<\/a>, the offspring organisation of\u00a0Tompkins Conservation<\/a>. <\/p>\n

Rewilding Argentina\u2019s planning for the giant river otter program began in 2017. But they\u2019ve faced steep challenges, including obtaining suitable mates from zoos around the globe, processing authorisations for their international transfer, and establishing breeding pairs to form the gregarious family units that live and hunt together in the wild.<\/p>\n

Charismatic and playful, the giant river otter is the world\u2019s largest otter, measuring up to 1.8m and weighing 33kg.<\/p>\n

They live and hunt in family\u00a0groups, and once inhabited nearly the entire watershed of the Paran\u00e1 River in the northern and eastern regions of Argentina. The last breeding population was seen in 1986, with only occasional solitary individuals, most likely dispersed from nearby countries, spotted since then.\u00a0<\/p>\n

Located near the borders of Paraguay and Brazil, the Iber\u00e1 wetlands is one of South America\u2019s largest (3.2 million acres, including two million acres of protected area) and most important watersheds. <\/p>\n

As droughts and massive wildfires increase in frequency, the disturbances threaten the freshwater resources of the region\u2019s diverse wildlife, alongside millions of people in Argentina. Having functional, intact ecosystems is considered crucial in order to combat these changes in climate.\u00a0<\/p>\n

Sitting at the top of the wetlands\u2019 aquatic food chain, the giant river otter has a key role to play in the health of the wetlands. “The giant river otter is one of the largest aquatic predators in the wetlands of South America, and it\u2019s a particularly active and voracious species,\u201d says\u00a0Sebasti\u00e1n Di Martino, conservation director of Rewilding Argentina.\u00a0<\/p>\n

\u201cThey mainly prey on fish, so their presence will likely impact the fish populations here. It\u2019s a dynamic we need to better understand because, more than recovering one species, we want to recover its ecological role in the ecosystem, so we\u2019re measuring the diversity and abundance of fish species in Iber\u00e1, via a procedure that assesses DNA in the water and tells us the species that are present and their numbers. We will be monitoring these fish populations for differences post-reintroduction.\u201d<\/p>\n

Wildlife translocations are complex and potentially dangerous for the animals. “There are many challenges, especially when working\u00a0with animals that were born in captivity and have spent their whole lives there, like these giant river otters we\u2019re setting free,\u201d explains\u00a0Di Martino.<\/p>\n

“In this case, the animals have spent long periods acclimatising, years in this case, in pre-release pens, in the same environment that they will inhabit once free. <\/p>\n

“They have learned to dig their own dens, and capture live prey, and know the vegetation and water of the region. They have spent a substantial amount of time learning to adapt to the environment they will live in.\u00a0<\/p>\n

“As with our other reintroduction projects, they will be monitored, so we can follow their adaptation and the challenges that they will encounter. We\u2019ve had to develop special technologies, since satellite GPS had never been used to monitor this kind of otter, and we\u2019ve had to design a new kind of harness with special materials, since regular collars wouldn\u2019t work on them.\u201d<\/p>\n

To help the permanent recovery of the species, additional releases are planned in the Iber\u00e1 wetlands and the Chaco region. “The species will not\u00a0recover with the release of just one family,\u201d says\u00a0Di Martino.<\/p>\n

“Rewilding Argentina have been working to bring back the species for eight years with the world\u2019s first reintroduction program, breeding giant otters for wild release. We\u2019ve paired multiple adult giant otters gifted from zoos around the world, and they\u2019ve successfully formed families and are living in pre-release pens in the wetlands. <\/p>\n

“Soon, when these individuals are ready, we hope to release them as two family groups into the wetlands.”<\/p>\n

Main image credit: Rewilding Argentina<\/p>\n

More amazing wildlife stories from around the world<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"A family of four otters, including two pups born in captivity, have been set free in the Iber\u00e1…\n","protected":false},"author":3,"featured_media":30063,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27],"tags":[159,67,132,68,837],"class_list":{"0":"post-30062","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-science","9":"tag-united-states","10":"tag-unitedstates","11":"tag-us","12":"tag-wildlife"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/114778461211825279","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/30062","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=30062"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/30062\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/30063"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=30062"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=30062"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=30062"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}