Aerial view of the Iriri River on Arara Indigenous land, in the Amazon, on March 15th, 2019. (Photo: Mauro Pimentel/AFP/Getty Images)

As countries try to stall the planet's spiral into a sixth mass extinction, it's not always clear what, if anything, is working. There are plenty of news stories about what isn't: Species aren't adapting fast enough to keep up with climate change, habitat loss, pollution, and predation. Currently one million plant and animal species are on the brink of extinction—more than at any other period in human history.

But a growing body of research shows that one possible key to preserving more biodiversity might be giving Indigenous communities a bigger role in land management. The latest study to reach that conclusion was published in Environmental Science & Policy last week. "Going forward, collaborating with Indigenous land stewards will likely be essential in ensuring that species survive and thrive," the study's lead author, Richard Schuster, said in a press release.

The study compared land management and species data in three of the largest countries in the world: Canada, Brazil, and Australia. "We looked at three countries with very different climates and species, to see if the pattern held true across these different regions—and it did," said the study's co-author, Ryan Germain.

By comparing species counts from more than 15,621 geographical areas in the three countries, the researchers found that the total numbers of birds, mammals, amphibians, and reptiles were highest on lands managed or co-managed by Indigenous communities. Indigenous-managed lands even had higher biodiversity than conventionally protected areas like parks and nature preserves that were being managed without Indigenous oversight.

The study comes close on the heels of news of the murder of the Indigenous leader Emrya Wajãpi by a group of miners in Brazil, where the country's president is working to roll back protections on Indigenous land—part of a larger trend of escalating violence against environmentalists. It also builds on existing research showing that, although Indigenous peoples make up less than 5 percent of the world's population, Indigenous-managed lands support roughly 80 percent of global biodiversity.

The latest findings are an evidence-based reproach of countries that have disputed Indigenous land rights and forced the removal of Indigenous communities to create protected conservation areas. And it confirms the conclusions of the United Nations report released earlier this year that found Indigenous communities are not only better at preserving biodiversity, but also better at landscape preservation and managing environmental hazards like pollution.

"This is a watershed moment in acknowledging that Indigenous and local communities play really important roles in maintaining and managing biodiversity and landscapes that the rest of us can learn from," ecologist Pamela McElwee, one of the U.N. report's lead authors, told Scientific American in May.