128,000 hectares.

Carbon Stock:

28,2 millions of metric tons.


Forest of quebracho, algorrobos and palo santo trees, along with gallery forest, grasslands, marshes and lakes formed from the flooding of the Bermejo River.

Important conservation values:

A representative sample of the Dry Chaco region and the inter-riverine areas along the Bermejo River. Good populations of threatened species like the white-lipped peccary and collared peccary, the giant armadillo, giant anteater, tapir, and the maned wolf. The Chacoan peccary and the ocelot are present, along with one of the last jaguar individuals in Chaco. The park contains a high diversity of species and can be a corridor along the Bermejo River between the Atlantic forest of the interior and the montane cloud forest.

Coordinating Team:

Gerardo Cerón
Conservation Coordinator

Gerardo has a PhD in Biology from the National University de Comahue, in Bariloche. At 10 years old, he moved from Buenos Aires to Dina Huapi, a small village close to the Patagonia mountains. There, his love of nature deepened and at that young age he decided to become a biologist. After spending 12 years studying the Torrent duck, a species threatened with extinction, he came to understand that to merely study a species is not enough, on has to “get one’s hand dirty” and act in order to change the course of conservation. That led him to begin to work with Rewilding Argentina in 2017, on the Impenetrable Project. For two years, he conducted the baseline studies of vertebrates in the park, cataloguing over 500 species. He is currently the Coordinator of Rewilding for this project, taking the first steps to restore proper ecological functions to Impenetrable through the reintroduction of species extinct in the region and by using satellite technology to monitor key species.

Marisi López
Institutional Relations and Nature Tourism Coordinator

Marisi López has a degree in Public Relations. In 2005, she joined Fundación Rewilding Argentina to work on the Iberá Project, Corrientes, where she has led the process of opening up to public use and donating tourist portals to the State since then. In the El Impenetrable Project, Chaco, Marisi leads the development of Nature Tourism and the institutional relations with the press, civil society, and community actors.


An oasis of biodiversity

The ecoregion of the Gran Chaco contains the second largest continuous forest of South America, after the Amazon. After observing that there were few protected areas within this great continental plain, our team began in 2011 to work on the creation of a national park in a part of the Chaco contained within La Fidelidad ranch, a vast expanse of forest stretching across the Teuco and Teuquito Rivers. 

In 2014, Impenetrable National Park was created, covering 128,000 hectares in the province of Chaco, although it was only in April 2017 that the National Parks Administration was able to enter and take care of the place. In order to assure that the park is a representative sample of the Chaco ecosystem and to have sustainable populations of large mammals, it still remains a goal to protect the lands on the north side of the Teuco River.

Our foundation works within the park in collaboration with the National Parks Administration, and for that purpose we have established a field station and a permanent team of biologists, veterinarians and other experts. To date (2021), 20 species of fungi, 497 species of plants, 587 species of arthropods, 72 species of fish, 36 of amphibians, 51 of reptiles, 345 species of birds, and 58 species of mammals were inventoried in the Park. Some of these species were not previously recorded in the province of Chaco.   

These base line surveys allow us, also, to identify the species that have recently gone extinct in the region and to understand the causes that caused their disappearance. The area of the Park offers and ideal habitat to restore stable populations of jaguar, pampas deer, guanaco, marsh deer and giant river otter, and the reed-fooed tortoise, the majority of which are species that are in danger of extinction in Argentina.

The natural and cultural diversity of the Impenetrable is threatened

The part of La Fidelidad ranch, in the province of Formosa on the north side of the Teuco River, is not part of the National Park and is not protected. In fact, it is currently being divided into parcels for timber extraction and ranching. The 100 kilometers along the Teuco River, which today is the northern limit of El Impenetrable National Park, are often used by sport fishing and hunting that put at risk the survival of peccaries, tapirs, brocket deer, the fish species of dorado and surubi, and, above all, the large cats such as the jaguar, which has been declared a Natural Monument in the province and in all of Argentina and which is critically endangered in the Chaco region.

From 2011, we have collaborated with provincial and national park guards to assure that environmental laws in the region are followed, with NGO’s and with biologists to augment the scientific knowledge of the wildlife, and with the government of the province of Chaco increase the promotion of nature tourism in the region and to improve the economic opportunities of the neighboring communities.


The province of Chaco and especially Impenetrable National Park, in the Dry Chaco, have rare examples of landscapes where certain unique environments, like forests of quebracho, algorrobo and palo santo, and their associated wildlife, remain relatively well conserved. 

However, the populations of some species of these forests have decreased at an alarming rate, almost to the point of extinction in the last decades, species like the jaguar and the red-footed turtle.  In the wetlands and grasslands of the Dry Chaco, the extinction of several large species has been verified. In the grasslands, the guanaco and the pampas deer has disappeared. In the wetlands associated with the Bermejo and Bermejito Rivers, the marsh deer and the giant river otter have gone extinct. Other species, like the ñandú, the collared peccary, and the giant armadillo, seem to have low population numbers.  

Our objective is to restore the splendor of wildlife of the Impenetrable of Chaco through the reintroduction of species that have been extirpated from the region and active management of some of the most threatened environments, such as the grasslands. In this way, the region will recover its most iconic inhabitants and the critical roles that each play in the ecosystem.

El Teuco Field Station

Part of our Rewilding Argentina is based at the Teuco Biological Station, where they are working on numerous projects of investigations, monitoring, capacity building and other tasks for the development and conservation of the Park.  Staring in mid 2018, we carried out a base line biodiversity study of El Impenetrable National Park, which is the most complete inventory of flora and fauna that has ever been carried out in this protected area.  This information has been indispensable in order to make the best management decisions for the Park.


Qaramta and Tania, together in El Impenetrable National Park, during the first attempt in history to breed a wild male jaguar with a captive female. Camera trap photo.

The jaguar has been nearly driven to extinction in the Argentine Chaco. Investigators speculate that less than 20 individuals survive across a very extensive territory. The last sightings of the species have been of solitary males, and many of those have since been killed by hunters. 

In September 2019, jaguar tracks were found in El Impenetrable National Park for the first time since the Park’s creation. Quick action by the rewilding team allowed us to obtain a video recording, made via a camera trap (this was the first time a jaguar had been filmed in the Argentine Chaco), and later to capture the jaguar to fit him with a satellite radio collar. From that day, this four-year-old, 114 kilo male named Qaramta (meaning “Indestructible” in the indigenous Qom language) is monitored daily with the latest technology. Through this, we have learned that he uses the territory of the ex-estancia La Fidelidad in Chaco (which is now El Impenetrable National Park) and in Formosa.

A breeding project, approved in June 2020, allowed us to aid the cross between Qaramta and Tania, a captive female jaguar. Our goal is to establish a sustainable population of jaguars in El Impenetrable National Park with one of the last wild specimens living in Argentine Chaco.

Inside a pen built especially for this feat, Tania and Qaramta finally bred between September 17th and 21st, 2021. After their time together, Qaramta returned to his life in freedom and, 100 days later, Tania gave birth to two healthy cubs, Takajay and Nalá.

The cubs will be separated from their mother at the age of one to become fully independent. They grew up with the least human interaction possible and developed hunting skills with their mother. Then, when they reach adulthood, they will be released into the wild in a hopeful attempt to restore the jaguar’s future in the Chacoan Impenetrable.


The tapir is the largest herbivore of El Impenetrable National Park and a key species in the proper functioning and structure of the forests in the north of our country. The tapir has gone extinct in a good part of its original range and barely survives in the rest, and has therefore been categorized as Vulnerable to Extinction.  

However, in El Impenetrable National Park, there is a population that is apparently in a good state of conservation and it is relatively easy to see the animal in the Park. To better understand the biology and ecology of this species, we have started a monitoring project using camera traps. This data is complemented by the information we receive from a few tapirs which have been fitted with collars that have satellite-connected VHF and GPS transmitters, technology which is being used for the first time on this species in Argentina.

The rewilding team in Impenetrable places a satellite monitoring collar on a tapir. Photo: Gerardo Cerón

Marsh deer

In the past, the marsh deer inhabited the entire watershed of the Teuco River, from the provinces of Salta and Jujuy to its confluence with the Paraguay River. El Impenetrable National Park has many good environments for this species, as it is located in the inter-riverine region between the Teuco and Teuquito Rivers and has extensive wetlands, created by the periodic flooding of these rivers.

The marsh deer is currently extinct within El Impenetrable National Park and in all of the wetlands of the Dry Chaco. As of 2022, we started a project to return this largest of South American deer to these lands. The arrival of two deer from captivity marked the beginning of restoring a lost ecological role in El Impenetrable. Soon, more wild individuals from Iberá will join the project in the first-ever translocation of animals between national parks in Argentina.

Red-footed Tortoise

The red-footed tortoise is the largest tortoise in Argentina, where it is ecologically extinct. The last remaining individuals live in fragmented habitats in Formosa Province. Once abundant in the Argentine Great Chaco region, humans hunted this giant tortoise that can weigh over 20 kg and destroyed its habitats, driving it extinct in a vast part of the region, including El Impenetrable National Park.

By consuming a wide array of fruits, the red-footed tortoise plays a vital role in dispersing seeds and thus shaping the forest’s structure and recuperating degraded areas. As of 2022, 40 tortoises arrived from the Urutau Rescue Center in Paraguay to begin restoring the species in Chaco ecosystems.


In the past, large herds of guanacos inhabited Great Chaco’s grasslands. Hunting and the introduction of domestic cattle drove the species almost extinct in the region, leaving a few individuals that survive in reduced and fragmented populations. In an ambitious project, we seek to reintroduce the species into El Impenetrable National Park by translocating family groups of wild guanacos.


The Impenetrable Chaco, with its lavish forest of quebracho and algarrobo trees, its looping rivers with sandy beaches and its abundant wildlife, invites us to become adventurers and explorers of a little-known world.

El Impenetrable National Park offers the possibility to watch strange and fabled animals —like the tapir, the giant anteater, the giant armadillo, the peccary and puma and more than 300 species of birds; to listen to the silence of the forest, to explore its horseshoe-shaped lakes and to navigate the majestic Bermejo River. 

Since 2013, we have established our team on the coast of this river, within the National Park. Working together with the National Park Administration, our objectives are to heal and restore the ecosystems of the wetlands and grasslands, understand the tourist potential of the region and communicate our values to society. We are therefore working to build capacity among the local people so that they are able to offer tourist services to visitors. 

The Institute of Tourism of the Province of Chaco, along with the National Secretary of Tourism is working on the formation of a “tourist corridor” in Impenetrable, with the building of an interpretive center in nearby Miraflores, two huts for sleeping and eating at the La Armonía and Nueva Población entrances and intermediate stops with restrooms and tourist information.

The Bermejo River. Photo: Douglas Tompkins.


Throughout the six years that it took to create El Impenetrable National Park, between 2012 and 2018, we worked with the government of Chaco Province and the local communities to establish centers which offer tourist services in the communities closest to the entrances of the future Park.  Also, with the support of the Environment Secretary of Argentina, we worked on “Forest and Communities” projects with groups of local people living in two rural communities neighboring the Park, La Armonía and El Chañar (Las Flores).

Entrepreneurs by Nature

Entrepreneurs by Nature is a program led by Rewilding Argentina that seeks to contribute to the wellbeing of rural communities neighboring protected areas by supporting the creation of local ventures that are respectful of wildlife and natural ecosystems.

The program works accompanying production practices and tourist services, creating the link between clients and producers, empowering entrepreneurs so they can reach commercial independence, and fostering community development related to conservation-driven income opportunities.

By committing to the Entrepreneurs by Nature seal, the entrepreneurs produce new incomes while becoming guardians of their natural environment, thus aiding the park’s mission of sustaining wildlife and biological processes, scenic beauty, and cultural richness.

Discover more at

Kayaking through the Bermejito River is an Entrepreneurs by Nature certified product. Photo: Estrella Herrera.

Community wellbeing program

Behind every entrepreneur, there is a family. We accompany the entrepreneurs’ families, focused on women and youth, to improve their wellbeing with training courses, exchanges with other nature-based tourism destinations, food sovereignty actions, improvements in infrastructure, accessibility and connectivity, and environmental education.

Men and women from El Impenetrable visit Iberá National Park to experience a well-established nature-based tourist destination. Photo: Matías Rebak.