In January 2018, a camera trap on San Alonso Island in Corrientes Province, Argentina, recorded footage that the research team had to review twice before acknowledging what it showed. Two jaguar cubs, alive and moving, had been born on Argentine soil for the first time in nearly 70 years. The field manager watched the clip four times before sending it to the team. She attached no text to the message, only the file. Everyone who opened it understood immediately why.
The Esteros del Iberá is the second-largest wetland system in South America. In the Guaraní language, the name Iberá means “glistening waters.” The region supports roughly 4,000 plant and animal species, 350 bird species, and 60 reptile species. It is home to thousands of capybaras, caimans, marsh deer, giant anteaters, and giant otters.
For about 10,000 years before the system began to decline, the jaguar was the apex predator in this landscape. The species shaped where capybaras grazed, how long they stayed in one place, and how many survived. That, in turn, influenced how much vegetation remained, how many birds could nest, and how many insects had cover. A single predator maintained the balance of the entire system without any deliberate design.
By the 1950s, the jaguar had disappeared from Corrientes entirely. What replaced it was not stability. It was a slow collapse that took decades to become fully visible.
Capybaras are not an invasive species. They are native to South America and had always been a natural part of the Iberá system. Under jaguar predation, their numbers stayed within a range the environment could support. When the jaguar vanished, that pressure vanished with it.
The world’s largest rodent, which can weigh up to 70 kilograms, began gathering at water sources in numbers no wetland plant system was designed to support. On San Alonso Island, population density eventually reached 129 individuals per square mile. An adult capybara consumes three to four kilograms of vegetation per day. At that density, the daily loss of plant matter per square mile was not merely a conservation concern. It was a destruction rate.
A four-year study in Iberá documented the results directly. In high-density capybara areas, grass was significantly shorter. Plant biomass dropped sharply. The grassland structure compressed into a flat, uniformly short surface. Ground-nesting birds lost the cover that had hidden their eggs. Insect shelter declined. Soil temperatures changed. These were measured data from a natural environment being consumed by a population that had lost the animal designed to regulate it.
Hunting, pasture burning, cattle ranching expansion, and decades of exploitation had pushed the jaguar out of Corrientes. The result was not a new stable balance. It was an ecosystem in extended decline, slow enough to seem manageable year to year but largely irreversible in aggregate.
That was the situation in 1997, when a man with no scientific background and no government mandate began buying land in northeastern Argentina for reasons no one could explain.
Doug Tompkins was the co-founder of The North Face and later the Esprit clothing brand. He had made more money from outdoor apparel and lifestyle industries than he needed. By the late 1980s, he concluded that the consumer economy he had helped build was destroying the natural systems he had spent his career selling products related to. He sold his shares and stepped away from the business world.
With his wife, Kris Tompkins, a former CEO of Patagonia, he began purchasing degraded land across South America with a single stated purpose: restoring ecosystems on a large scale before they passed the point of no return.
The arrival of wealthy Americans in Patagonia buying hundreds of thousands of acres of private land produced the predictable reaction. What did they want with the water? Was this an American land grab? Why would they not explain what they were building?
They were not building anything. They were buying former cattle ranches, heavily logged forests, and degraded wetlands, removing the commercial operations, and leaving the land to begin recovering on its own. The theory was direct: damaged land, given enough time and protection from continued exploitation, would regain its biological complexity by itself. The hard part was acquiring enough of it to create corridors wide enough for that recovery to spread.
In Iberá alone, through the Conservation Land Trust, Tompkins and his collaborators acquired nearly 395,000 acres of former ranch land starting in 1997. About 150,000 hectares were directly restored. Most were eventually donated to Argentina and now form the core of what is known as Iberá National Park, covering roughly 1.7 million acres.
Tompkins died in 2015. The project he started did not stop. The jaguar reintroduction program began officially in 2010.
The team leading the program understood that if anything went wrong, the error would be permanent. In 2012, a semi-wild reintroduction center was built on San Alonso Island, completely isolated from human presence and spanning hundreds of acres.
The first animals arrived in 2015 from rescue centers in Brazil, Paraguay, and Argentina. Multiple source populations were necessary because Argentina had fewer than 200 wild jaguars remaining, and the genetic problems of small populations were clear. Building a new population from a single small group would produce inbreeding that worsens across generations, weakening immune function and increasing the likelihood of developmental defects. Genetic diversity from multiple lineages was the only structure that could hold.
Each jaguar inside the enclosure had to hunt its own live prey, including capybaras and wild pigs. Human contact was kept to a minimum. Every animal wore a GPS tracking collar and was monitored through surveillance cameras. This was the standard, not emotion or optimism. Any animal that did not display functional wild behavior remained inside the enclosure. A reintroduction that produced a jaguar comfortable around humans would not be a conservation success. It would be a source of danger. The Iberá wetlands border working cattle ranches. A predator that does not fear humans has one likely path in that environment.
In 2018, the footage no one expected to see so soon appeared. The cubs’ mother was María, a female brought from Brazil who had proven herself as a hunter inside the enclosure. Their father was Jatobazinho, a male selected to strengthen genetic diversity. One of the cubs was named Arami, a Guaraní word meaning “piece of sky.” She became the first jaguar born on Corrientes soil in nearly seven decades.
In 2021, the first jaguars were released into the wild in Iberá. By 2022, about eight individuals were moving through the wetlands as free animals.
The capybaras noticed immediately. GPS collar data and camera records began showing behavioral shifts within months of jaguars appearing in the area. Capybaras increased their movement frequency. They spent less time in extended grazing positions in open areas. They avoided locations where jaguar activity had been recorded.
This response is not simply instinct. A capybara population that had not experienced jaguar predation for 70 years does not carry an innate programmed fear of the jaguar. It relearns that fear under the pressure of lethal risk. The animals that change their behavior are the ones that survive. Those that continue grazing in open areas near jaguar activity do not. Behavioral selection works through the group in real time, and information about survival costs spreads among the animals that remain.
In areas where jaguar activity was documented, grass height rose noticeably. Plant biomass began to recover. Grassland structure diversified. The plants that form the foundation of every other level of the system returned to the areas where grazing pressure had dropped because the capybaras were afraid to stay.
In early 2022, the restoration timeline was disrupted by an event no schedule had anticipated. Corrientes Province experienced one of the worst wildfire seasons in its recorded history. Months of drought, extreme heat, and continuous wind dried the wetlands in ways not seen in recent memory. Iberá is supposed to be too wet to burn on a large scale. More than 2.5 million acres burned across the province. Nearly 60 percent of Iberá National Park was affected by fire and drought within weeks.
Restoration corridors, habitats recovering from decades of cattle pressure, and areas where reintroduced animals were establishing territories all lay within the fire perimeter. GPS collars were monitored around the clock to determine which individual jaguars were still alive. Conservation teams moved by boat through burned areas. Drones scanned regions inaccessible on foot.
The conservation team’s assessment was cautious. Habitat areas that had taken a decade to recover from cattle pressure had burned. Some individuals moved to land edges in ways that created new conflict risks with neighboring cattle operations. But the jaguar population held.
By 2024, 33 free-roaming jaguars were recorded in Iberá. Twelve cubs were born in the wild that year, not in the reintroduction enclosure and not with human support, but in the wetlands themselves. By 2026, approximately 50 jaguars were identified within the Iberá ecosystem. This number includes multiple generations. It includes animals that have never entered an enclosure. It includes cubs that learned what Iberá is from a jaguar, not from a human.
The jaguar was not the only species to return. The team worked through a sequence of smaller reintroductions before attempting the apex predator. The first giant anteater, a victim rescued from trafficking, was released in 2007. She lived for 15 years and gave birth to seven offspring. By 2022, the region had two self-sustaining anteater populations. Pampas deer returned. Collared peccaries were reintroduced. Red-and-green macaws flew over Iberá again. Giant otters were in a pre-release phase by 2024, with seven pups born that year. The jaguar’s return was the cornerstone of a restoration chain that had been running for 17 years.
The economic shift surprised people who had not followed the data on what apex predator reintroduction produces for neighboring communities. The towns around Iberá, once dependent on cattle ranching and wetland resource extraction, now have wildlife guides, safari boat operators, park rangers, camera-trap monitors, birdwatching operations, and ecotourism lodge infrastructure. Time magazine named Iberá one of the greatest places in the world, citing this environmental revival specifically.
Some men who had spent their lives hunting jaguars now work as guides for international tourists paying for the chance to see a live jaguar. A living jaguar in the Iberá wetlands generates economic value through tourism that exceeds what it might kill in livestock over a full season. That calculation has shifted reintroduction policy faster than any conservation argument.
The camera-trap footage from January 2018 has been viewed millions of times since the team published it. Two cubs only weeks old move through the grass in the wetlands of northeastern Argentina. The silence that lasted 70 years in the Corrientes landscape ended in that clip. Arami, the piece of sky, is alive. The capybaras know it. The grasslands are already responding. The wetlands are answering.
