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Biodiversity loss

Why are land ecosystems collapsing worldwide?

73%
average decline in the size of monitored wildlife populations, 1970–2020
WWF / ZSL, 2024
3–4×
as many bird and mammal species would have gone extinct without today's conservation work
Bolam et al., Conservation Letters, 2020
Biodiversity loss, the disappearance of species and ecosystems on land, is running tens to hundreds of times faster than the natural rate.

Extinction is permanent, and as species disappear, ecosystems lose the interactions that keep them functioning, weakening the systems people depend on for food, water and climate stability.

Forests and wetlands that filter water and absorb floods weaken as biodiversity is lost. Habitat loss also pushes wildlife and people into closer contact, raising the risk of conflict and disease crossing between species.

Brazil
High severity

Cattle ranching and soya are clearing the Amazon, the most species-rich forest on Earth, toward a point where it could dry into savanna.

Nature is being lost fast in wealthy regions too, from the intensively farmed landscapes of western Europe to North America's grasslands.