In 1975, while scientists considered a peccary they knew only from fossil bones extinct, that same animal —the taguá— was trotting alive through the thorny forest of the northern Paraguayan Chaco. Its 'rediscovery', published in the journal Science, turned the world's eyes to one of the most inhospitable and least explored regions of South America: a sea of dry scrubland, crushing heat and absolute silence where the jaguar still reigns and where a solitary hill is, for the Ayoreo people, the center of the world. That same year, Paraguay decided to protect that wild heart. Defensores del Chaco National Park was created in 1975 with the goal of protecting a representative portion of the Paraguayan dry Chaco: its thorny-forest and savanna ecosystems, its threatened wildlife and the singular Cerro León. With its enormous surface of about 780,000 hectares, it became the country's largest protected area and a key piece of the national park system, at a time when nature conservation was beginning to gain ground on the public agenda.
Its name is neither accidental nor merely geographical: it pays homage to the 'defenders of the Chaco', that is, to the Paraguayan soldiers and combatants who fought in the Chaco War (1932-1935) against Bolivia, a conflict fought precisely in this region. Thus, the park unites the conservation of nature with the historical memory of one of the most decisive and painful episodes of national history.
Protecting this territory also had a strategic and symbolic meaning: it was about preserving the wild heart of a region for which the country had shed blood, and recognizing its natural value at a time when the advance of cattle ranching and deforestation were beginning to threaten the Chaco. The park thus remained a great reservoir of nature in the far northern Chaco, and in recent years it appears on Paraguay's tentative list for its eventual nomination as a UNESCO World Heritage Site.
The park protects one of the most characteristic and at the same time most threatened environments of South America: the Gran Chaco, the largest expanse of dry forest on the continent. Here dominate the red and white quebracho, the palo santo, the carob trees, the samu'u (silk floss tree) and the columnar cacti, in a mosaic of thorny forest, savannas and palm groves adapted to a climate of extreme heat and long droughts. Cerro León, an isolated massif of volcanic origin up to 624 meters high and about 52 km in diameter at its base, breaks the immense plain and provides particular microenvironments at its geographical center.
This environmental harshness paradoxically houses a very rich wildlife. The park is one of the last great refuges of the jaguar or yaguareté in the country, and home to pumas, ocelots (oncilla), jaguarundis, tapirs, anteaters, several species of armadillos, ka'i mirikina and ka'i pyhare monkeys, guanacos and the three peccaries of the Chaco.
Among the latter is the most famous scientific find of the region: the taguá or Chaco peccary (Catagonus wagneri), a species that science knew only from fossil remains and that was considered extinct since the Pleistocene. In 1975, a team of biologists confirmed, based on rumors and clues from local inhabitants, that the species was still alive in the Paraguayan Chaco, and published the find in the journal Science, in one of the most resounding zoological discoveries of the twentieth century in South America.
Long before being a protected area, this region of the Chaco Boreal was —and remains— ancestral territory of the Ayoreo people, one of the indigenous peoples of the Gran Chaco with a presence in Paraguay and Bolivia. For the Ayoreo, Cerro León holds a central place in their worldview: it's considered, since time immemorial, the center of the world, a site of deep spiritual and territorial value that structures much of their symbolic relationship with the Chaco territory.
In the north of the park, in the expanse surrounding Cerro León, some of the last clans of the Ayoreo people who live in voluntary isolation, without contact with the outside world, survive to this day —along with those of neighboring Bolivia, they are among the few groups in that condition remaining in the whole American continent outside the Amazon. Their presence makes this part of the park a strictly protected zone, where access and any attempt at contact are prohibited by law and ethics, given the health and cultural risk that exposure to outside populations represents.
This reality adds to Defensores del Chaco Park a dimension that goes beyond biological conservation: it's also a territory of indigenous rights and living memory, where the protection of the environment and respect for isolated native peoples are deeply intertwined.
The park's name refers directly to the Chaco War (1932-1935), the armed conflict between Paraguay and Bolivia fought largely in this same region of the Chaco Boreal, then a semi-desert and practically unpopulated territory whose sovereignty was in dispute. The war, one of the bloodiest in twentieth-century South American history, left more than 100,000 dead on both sides and ended with a result favorable to Paraguay, consolidated in the 1938 Peace Treaty.
The Paraguayan troops that fought in the north and west of the Chaco —the same arid, hot spots that today make up the park— faced extreme conditions: the scarcity of water, the scorching heat and the enormous distances were, on many stretches, enemies as lethal as the Bolivian bullets. The resistance and sacrifice of those soldiers, many of them young recruits from the Eastern region of the country, were etched into the national memory as a founding episode of identity.
In creating the park in 1975 and naming it 'Defensores del Chaco', the Paraguayan state sought to pay permanent tribute to those combatants, forever linking the conservation of this wild territory with the memory of those who defended it with their lives four decades earlier.
The remote condition of Defensores del Chaco Park is, at once, its best defense and its greatest challenge. Its isolation —enormous distances, difficult roads, absence of services and extreme climate— has kept it relatively safe from direct human pressure, but also hinders its control, its management and tourist visits. The management, in the hands of the national environmental authority (today MADES), must confront the vastness of the territory with limited resources.
Around the park, the Chaco is experiencing one of the fastest transformations on the planet in terms of forest loss: the expansion of cattle ranching and agriculture has caused intense deforestation in recent decades, fragmenting habitats and further isolating the protected areas. This makes Defensores del Chaco and the region's conservation corridors fundamental pieces for the survival of species like the jaguar and the taguá, and an increasingly critical refuge in the face of the advancing agricultural frontier.
For the visitor, the park offers an experience of nature in an almost pure state, but it demands respect, planning and self-sufficiency. More than a mass tourist destination, it's a territory for conservation, research and responsible adventure —including strict respect for the isolated Ayoreo clans— a reminder of the value of the Gran Chaco and of the memory of those who, in another era, defended it in war.