Every day billions of people depend on wild flora and fauna to obtain food, medicine and energy. But a new United Nations-backed report says that overexploitation, climate change, pollution and deforestation are pushing one million species towards extinction.

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services – or IPBES – report said Friday that unless humankind improves the sustainable use of nature, the Earth is on its way to losing 12% of its wild tree species, over a thousand wild mammal species and almost 450 species of sharks and rays, among other irreparable harm.

Humans use about 50,000 wild species routinely and 1 out of 5 people of the world’s 7.9 billion population depend on those species for food and income, the report said. 1 in 3 people rely on fuel wood for cooking, the number even higher in Africa.

“It’s essential that those uses be sustainable because you need them to be there for your children and grandchildren. So when uses of wild species become unsustainable, it’s bad for the species, it’s bad for the ecosystem and it’s bad for the people,” report co-chair Marla R. Emery of the United States told The Associated Press.

Beyond the gloomy picture, the report also provides recommendations for policymakers and examples for the sustainable use of wild fauna and flora. A central point should be to secure tenure rights for Indigenous and local peoples, who have historically made sustainable use of wild species, the report said.

According to the study, Indigenous peoples occupy around 38,000,000 square kilometers (14,600,000 square miles) of land in 87 countries, equivalent to about 40% of terrestrial conserved areas.

“Their lands tend to be doing better in sustainability than other lands. And the common thread is the ability to continue to engage in customary practices,” said Emery, who is also a researcher with the U.S. Forest Service.

Emery argued it is essential to secure national and international systems, such as education, that promote the preservation of Indigenous languages, as it maintains the ability for older members to transfer traditional knowledge about sustainable practices to new generations.

An example of good practice is fishing arapaima, one of the world’s largest freshwater fish, in Brazil’s Amazon, co-chair of the report Jean-Marc Fromentin of France told the AP.

“It was a move from an unsustainable to a sustainable situation,” Fromentin said. “Some communities in Brazil created community-based management and then called some scientists to learn more about the fish’s biology and to put in place an efficient monitoring system. It worked so well that the model went to other communities and countries like Peru.”

Gregorio Mirabal, the head of Coordinator of the Indigenous Organizations of the Amazon Basin, who did not take part in the report, told the AP there had been already several U.N. studies stressing the importance of biodiversity and the threats posed by climate change, but they don’t bring about solutions.

The Indigenous leader mentioned growing problems in the region such as water contamination from mercury used in illegal mining and oil spillages. Moreover, those who oppose these practices face violence, such as the recent murder of an Indigenous warrior in a mining area, in Venezuela.

“There is irrational exploitation of natural resources in the Amazon, but there is no social investment to improve the health, educational, cultural and food situation of the Indigenous peoples,” Mirabal said.

The report was approved by representatives of the 139 member countries gathered this week in Bonn, Germany. It involved dozens of experts, from scientists to holders of Indigenous knowledge. IPBES is an independent intergovernmental body and is not part of the U.N. system, but it has the support of the United Nations Environment Programme and other bodies.