"The latest update to an important assessment found that populations had declined by an average of 69 percent since 1970. But that might not mean what you think."
"It’s clear that wildlife is suffering mightily on our planet, but scientists don’t know exactly how much. A comprehensive figure is exceedingly hard to determine. Counting wild animals — on land and at sea, from gnats to whales — is no small feat. Most countries lack national monitoring systems.
One of the most ambitious efforts to fill this void is published every two years. Known as the Living Planet Index, it’s a collaboration between two major conservation organizations, the World Wide Fund for Nature and the Zoological Society of London. But the report has repeatedly resulted in inaccurate headlines when journalists misinterpreted or overstated its results.
The assessment’s latest number, issued Wednesday by 89 authors from around the world, is its most alarming yet: From 1970 to 2018, monitored populations of vertebrates declined an average of 69 percent. That’s more than two-thirds in only 48 years. It’s a staggering figure with serious implications, especially as nations prepare to meet in Montreal this December in an effort to agree on a new global plan to protect biodiversity. But does it mean what you think?"
Catrin Einhorn reports for the New York Times October 12, 2022.