Rewilding: Jaguars return to Argentina’s wetlands 70 years after local extinction

Reintroduction of ‘keystone species’ will control populations of prey species and boost biodiversity, UN says

Rewilding efforts are returning jaguars, the largest predator in South America, to areas where the species has been driven to local extinction due to hunting and habitat loss.

In Argentina, just 200 Jaguars remain, but a reintroduction programme has returned a mother and two cubs to the country’s Iberá wetlands, 70 years after the species was last observed in the region.

They are the first of nine jaguars which will be released to repopulate the wetlands, which are a protected area covering almost 700,000 hectares and offering an abundance of wild prey for the big cats.

Jaguars are a “keystone species” - an organism vital for the continuation of the local ecosystem - as they control levels of prey which would otherwise overgraze habitats, reducing biodiversity. It is hoped their presence will help wildlife in the wetlands flourish.

The adult jaguar, named Mariua by researchers, was born wild before being rescued as an orphan cub in her native Brazil, while her two cubs Karai and Porã were born in captivity in September 2020.

They are the first jaguars to live in complete freedom in the Argentinian province of Corrientes, according to the organisation who introduced them to the area, Rewilding Argentina.

Mariua and her cubs have settled on a hill close to small patches of forests, as well as pastures and wetlands, the organisation said. Their movements are made through a very limited area of about 50 hectares.

Researchers say the mother has hunted capybaras on several occasions - the only prey detected in the family’s diet so far.

“Carefully re-introducing predators such as jaguars can help restore ecosystems. Without these species, biodiversity suffers and the services that nature provides can break down – from disease mitigation and soil protection to water system regulation,” said Doreen Robinson, Chief of Wildlife at the United Nations Environment Programme (UNEP).

The programme is supporting various international rewilding efforts in a bid to “help stem catastrophic biodiversity loss”.

UNEP is also running a campaign to raise awareness of the illegal wildlife trade and is working with governments and local communities to protect endangered species.

The third-largest feline on the planet, the jaguar has lost over half its historic range, leaving some populations geographically isolated and with dangerously reduced gene pools.

It is an important cultural icon too: the Guarani people of northeastern Argentina value the jaguar as a symbol of strength and an essential element of the region’s identity.

Saving the species was deemed a priority by the International Union for Conservation of Nature at the World Conservation Congress in September 2020.

“We congratulate the government of Argentina, Argentina’s National Parks and the Province of Corrientes for their commitment to rewilding this iconic species,” said Kristine Tompkins, president of Tompkins Conservation and a UNEP Patron of Protected Areas.

“As we start the UN Decade on Ecosystem Restoration 2021-2030, it’s time to recognise the central role that rewilding can play in restoring climate stability and planetary health.”

Sebastian Di Martino, Director of Conservation at Rewilding Argentina said other reintroductions have also helped the Iberá wetlands recover after hunting, decades of cattle grazing and huge monoculture plantations. He said bringing back top predators such as the jaguar and the giant river otter, as well as seed bearers like peccaries - a pig-like hoofed animal - and birds such as macaws is helping restore the rich biodiversity of the area.