The Living Planet Report, published by WWF with the Zoological Society of London, is the most quoted single statistic in conservation communications. The 2024 edition found a 73% average decline in monitored wildlife populations between 1970 and 2020. It is also, routinely, the most misquoted.
What the index measures
The Living Planet Index tracks 34,836 populations across 5,495 vertebrate species and measures how each population's abundance has changed relative to its own 1970 baseline. It then averages those rates of change.
That averaging step is the whole story. The index answers "by what proportion has the typical monitored population shrunk?" — not "how many animals are left?" A population of 100 frogs falling to 10 and a population of 10 million birds falling to 1 million contribute identically to the average, because both declined by 90%. The index is deliberately built that way so that large, well-counted populations do not drown out small ones.
What it does not mean
It does not mean the world has lost 73% of its wildlife. It does not mean 73% of animals have died. It does not mean 73% of species are gone. Each of these appears in circulation, and each describes a quantity the index does not measure.
The distinction matters practically, not just pedantically. A small number of catastrophically collapsing populations can pull the average down sharply while most monitored populations are stable — and research examining the index has made exactly that point. That is a real finding about where conservation effort should go, and it disappears entirely if the figure is reported as a simple headcount.
The breakdown that gets left out
The global average conceals the more useful detail:
- Freshwater — 85%. The steepest decline of any system, driven by dams, abstraction, pollution and habitat fragmentation. Freshwater habitats hold a disproportionate share of vertebrate diversity for their surface area.
- Terrestrial — 69%.
- Marine — 56%.
- Latin America and the Caribbean — 95%, the sharpest regional figure, reflecting Amazon deforestation and freshwater loss.
Why we still cite it
None of this makes the index unreliable. Stated correctly, it is a serious long-run measure of population trends assembled from tens of thousands of monitoring records, and its direction is not in dispute. The problem is a communications one: the headline is repeated without the definition, so an audience hears a claim that was never made, and the moment someone points that out the entire finding looks overstated.
We cite it as what it is — an average rate of decline across monitored populations — because a figure that survives scrutiny is worth more than one that lands harder.
When the next report is due
The Living Planet Report is published every two years. The 2024 edition, covering data to 2020, is the current release; the next is expected in late 2026. We will update this page against the primary source when it lands rather than reporting the first summary of it.
