Up to a million species face going extinct because of humans, a new UN report will say.
The loss of forests, clean air, clean drinking water, mangroves and pollinating insects is having a devastating effect on biodiversity.
We are about to see an imminent rapid acceleration in the global rate of species extinction, the report will warn.
The pace of loss is already tens to hundreds of times higher than it has been, on average, over the last 10 million years.
Half-a-million to a million species are projected to be threatened with extinction, many within decades.
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) report will be published on May 6, after delegates go through it line by line.
Wording may change, but the figures will remain the same.
Many experts think a so-called mass extinction event – only the sixth in the last half-billion years – is already under way.
The most recent saw the end of the Cretaceous period some 66 million years ago, when a 10-kilometre-wide asteroid strike wiped out most lifeforms.
Animals on earth
Scientists estimate that Earth is today home to some eight million distinct species, a majority of them insects.
A quarter of catalogued animal and plant species are already being crowded, eaten or poisoned out of existence.
The drop in sheer numbers is even more dramatic, with wild mammal biomass – their collective weight – down by 82 percent.
Humans and livestock account for more than 95 percent of mammal biomass.