The Living Planet Index (WWF & the Zoological Society of London, 2024 report, via OWID) aggregates the relative abundance of ~35,000 monitored populations of ~5,500 vertebrate species — mammals, birds, fish, reptiles, amphibians — indexed to 1970 = 100. The 2020 value of ~27 means those populations have fallen by ~73% on average.

It is an INDEX of average change, not a count of animals or species, and not a measure of extinction. A few steep regional declines (notably freshwater and the tropics) pull the global average down, so read it as the direction and scale of pressure on wild populations, not a headcount.

The Red List Index (IUCN & BirdLife, UN SDG 15.5.1, via OWID) is the complement to the Living Planet Index: where the LPI tracks population abundance, the RLI tracks EXTINCTION RISK. A value of 1 means all assessed species are Least Concern; 0 means all are extinct. The world index has fallen steadily — every year, more species slide toward the threatened categories faster than any recover.

In the ocean, overfishing tells the same story: the FAO’s share of assessed marine stocks fished beyond sustainable limits (via OWID) has climbed from ~10% in 1974 to over a third today — a steady erosion of the seas’ ability to feed both wildlife and us.

Protected land (UNEP-WCMC / World Bank, via OWID) is the share of the world’s land inside protected areas — now about a sixth, and slowly rising toward the global “30 by 30” goal. It is a genuine bright spot, with one honest caveat: a line on a map is not the same as effective protection, and it says nothing about the oceans or how well habitats actually fare inside.

The drivers of the decline are land- and sea-use change (habitat loss), overexploitation, pollution, invasive species and — increasingly — climate change. That is why eating less meat, cutting emissions, and refusing throwaway plastic all show up below as ways to ease the pressure.