One in five people around the world rely on wild animals, plants and fungi for food and livelihoods, according to a landmark assessment.

But many wild species are not being harvested sustainably, putting food security at risk, the report found.

In 2019, experts estimated that one million plants and animals could go extinct in coming decades.

And much of this is being driven by unsustainable fishing, hunting and logging.

Now a new report by the same influential body concludes that the sustainable use of wild species is critical for people and nature.

And climate change and increased demand is likely to push more species to the brink, putting food security at risk.

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is conservation scientists' equivalent of the IPCC group of climate scientists.

Their most recent assessment, approved by 139 countries in Bonn, Germany, focuses on how fishing, hunting and logging can be carried out more sustainably without damaging biodiversity and food security.

It found that billions of people across the world rely on 50,000 species of wild animals, plants and fungi for food, medicine, fuel, income and other purposes.

The assessment paints a picture of widespread exploitation of nature, with about a third of wild fish in the ocean overfished, more than 10% of wild trees threatened by unsustainable logging, and more than 1,300 mammals pushed to extinction by unsustainable hunting.

The biodiversity crisis. 

The loss of species and habitats is thought to pose as much danger to life on Earth as global warming does. The UN warns that a million plant and animal species are at risk of extinction in the coming decades unless rapid action is taken now.

Extinction is part of the evolutionary process - some species die away as others evolve. The problem is species are currently becoming extinct far more rapidly than is usual in evolutionary history. Scientists estimate species extinction is happening between 1,000 and 10,000 times faster than the normal "background rate". They warn the world is experiencing an extinction event comparable in scale with the disaster that saw the dinosaurs wiped out.

This matters because biodiversity underpins so much of the functioning of the natural world - from the food we eat to the air we breathe and the water we drink. It also helps protect us from pollution, floods and climate breakdown.

But UN negotiations to stem the tide of extinction in Geneva earlier this year ended in deadlock. This week delegates meet in Nairobi to try to reboot the talks. The aim is to agree 21 targets, including protecting at least 30% of the world's land and seas by 2030.

The hope is to provide a framework for a landmark international agreement under the UN Convention on Biological Diversity that will be signed by governments in Kunming in October. The ultimate goal could hardly be more lofty - for humanity to "live in harmony with nature" by 2050.