The World Wide Fund for Nature (WWF) says monitored wildlife populations worldwide have fallen by an average of 73 per cent since 1970, according to its latest Living Planet Report. The index, compiled with the Zoological Society of London, tracked 35,803 populations of 5,790 species of mammals, birds, reptiles, amphibians and fish between 1970 and 2022. Freshwater species showed the steepest fall by habitat, at 85 per cent, followed by terrestrial species at 69 per cent and marine species at 59 per cent.

Regional differences are large. Latin America and the Caribbean recorded a 95 per cent decline, Africa 80 per cent and the Asia-Pacific region 49 per cent. Yann Laurans of WWF France said the African figure partly reflects how rich the continent's biodiversity still was when systematic monitoring began, with declines occurring more recently, whereas much of Europe had already lost considerable biodiversity before the period started. The report names habitat loss and degradation as the most frequently reported threat, followed by overexploitation, climate change, pollution, invasive species and disease. It singles out the Congo Basin, the world's second-largest tropical rainforest, where farming, logging, mining and road building are adding to hunting and poaching pressure. African forest elephant numbers have fallen by more than 60 per cent in recent decades.

The report, titled "Science of Hope", stresses that loss is not irreversible. About half of monitored populations are stable or increasing, and WWF cites recoveries among tigers, green sea turtles, bluefin tuna, some western lowland gorillas and certain southern African elephant and black rhino populations. In southern Africa, it credits community-based management that gives local people a direct stake in conservation, along with anti-trafficking work, judicial reform and reduced corruption. Lead author Mike Barrett said it is "not too late", though the report warns that successes remain fragile and that the challenge is now delivering solutions at sufficient speed and scale.

The figure needs careful reading, researchers caution. Writing in The Conversation, scientists who work with biodiversity data stress that it does not mean 73 per cent of animals have vanished; it is the average change in the size of populations that are monitored. Monitoring is patchy and resource-intensive, and the data come from ad hoc studies, monitoring programmes and records for harvested species. Raw records show roughly as many increasing populations as decreasing ones, and the index may over-represent protected, relatively undisturbed areas, which could lead to underestimating declines. It might also over-represent threatened or harvested species, which could push the other way. The index gives extra weight to under-sampled regions such as Africa and South America to compensate, and scientists are developing better methods.

Why this matters: WWF says half of global GDP depends on nature in some way. In 2023, about $7.3 trillion flowed into activities that harm nature, against $220 billion for protecting or restoring it, and the annual biodiversity funding gap is put at $942 billion. WWF calls for changes in energy, food and finance systems, naming agriculture as the biggest single driver of biodiversity loss. The findings come ahead of the COP17 UN biodiversity conference in Armenia on 19-30 October, where governments are due to review progress on commitments to halt and reverse nature loss. Durrel Halleson of WWF Africa called the findings "a stark warning, but also a call to action".