Lands managed by indigenous people possess the greatest levels of biodiversity. This is according to a study led by researchers at the University of British Columbia (UBC) and published in the journal Environmental Science & Policy.

The team compared levels of biodiversity in 15,621 areas across three of the largest countries in the world – Australia, Brazil, and Canada.

The size of the area did not appear to have much of an impact on species diversity. Neither did geographical location. Instead, what seemed to have the biggest influence on biodiversity was its management.

The results of the study show that land managed (or co-managed) by indigenous communities contained the highest levels of biodiversity. Protected areas (parks, wildlife reserves etc) came second, while those that were unprotected and selected at random came third.

"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," co-author Ryan Germain, a postdoctoral fellow at Cornell University, said in a statement.

"From frogs and songbirds right up to large mammals like grizzly bears, jaguars, and kangaroos, biodiversity was richest in Indigenous-managed lands."

According to the study authors, this is the first time biodiversity levels and land management has been compared on such an extensive scale, geographically speaking.

It comes shortly after a United Nations (UN) report, published in May, warned we are facing a biodiversity crisis, with up to a million species under threat. Many researchers have spoken of a "sixth mass extinction" – which is either imminent or already here depending on who you ask, but will with almost certainty threaten life as we know it regardless.

At the same time, many countries around the world are failing to meet even nominal targets as far as land protection is concerned, and some are actively working to remove protections.

Traditionally, conservation programs have been concerned with nominating certain places for protection and creating parks and reservations. But, the study authors point out, these areas tend to have little overlap with the geographic ranges of the world's more vulnerable species. Instead, areas are often chosen because they have relatively low economic value and biodiversity.

What's more, indigenous communities have often been pushed out of designated areas. Not only can this be damaging to the communities themselves, but it can also be also detrimental to the conservation agenda.

This study highlights how important it is to extend the reach of protected areas to cover more land – and more wildlife.

"Protected areas are a cornerstone of biodiversity conservation globally, but current levels of protection will be insufficient to halt the planetary extinction crisis," said Peter Arcese, the Forest Renewal B.C. Chair in Conservation Biology at UBC.

"We must manage a larger fraction of world's area in ways that protect species and leads to positive outcomes for people and the species they've relied on for millennia."

Today, indigenous communities manage or have tenure around 25 percent of the planet's land area. They have played an important role in environmental activism – and have faced the brunt of reactionary retaliation.

The study authors hope the results of the study will encourage greater collaboration with indigenous governments, organizations, and communities to improve biodiversity levels as well as indigenous rights.

"This suggests that it's the land-management practices of many Indigenous communities that are keeping species numbers high," said lead author Richard Schuster, the Liber Ero Postdoctoral Fellow at Carleton University, formerly of UBC.

"Going forward, collaborating with Indigenous land stewards will likely be essential in ensuring that species survive and thrive."