Report: Biodiversity loss, climate change driving an ‘escalating nature crisis’

Wildlife populations plummeted 69 percent worldwide between 1970 and 2018, according to a report released Wednesday by the World Wildlife Fund. Food systems were a key driver of this biodiversity loss, responsible for 70 percent of the population decline of land animals and half of the decline in freshwater species monitored for the report. Conservation alone will not be enough to halt these declines, wrote the authors, who said that scaling up sustainable food production is crucial.

“The findings are stark,” the authors wrote. “While we need to urgently act to restore the health of the natural world, there is no sign that the loss of nature is being halted, let alone reversed.”

Declines were especially steep in Latin America — where monitored wildlife populations fell 94 percent between 1970 and 2018 — and in freshwater ecosystems worldwide, where populations declined 83 percent. Wildlife populations in North America dropped 20 percent during that time, according to the report, which tracked the relative abundance of nearly 32,000 populations of 5,230 species across the planet.

The report also articulated a goal for global biodiversity: Nature positive by 2030. That is, reversing wildlife population declines by the end of this century, with full recovery by 2050. This goal should be a “guiding star,” the report’s authors said, much as the goals of limiting global heating to 1.5 degrees Celsius or reaching net zero emissions have helped focus the fight against climate change.

And while food systems are to blame for a great deal of biodiversity loss, they also present a prime opportunity for mitigation. In a food-focused companion report, the authors identified 20 food system “levers” that can be used to help wildlife populations recover, including maximizing crop yields to spare land, developing plant- and algae-based proteins, redirecting agricultural subsidies away from commodities and toward sustainable foods, and incorporating both human and environmental health in national dietary guidelines.

With two major international environmental conferences on the horizon — the UN Climate Conference in November and the UN Biodiversity Conference in December — the report called climate change and biodiversity loss “double, interlinked emergencies” that must be jointly addressed. Food systems, which account for 30 percent of global emissions, “must take center stage at these events” the report said.

Land use change, such as plowing prairie to plant corn or razing forests for subdivisions, is currently the biggest driver of biodiversity loss. But climate change will become the dominant cause in the coming decades if emissions are not curbed quickly, the report said. Climate change is already causing mass mortality events, like the death of 45,000 flying foxes on a single hot day in Australia in 2014. In the Costa Rican rainforest, warming temperatures reduced the number of foggy days, causing the golden toad to go extinct.

Each degree of warming will increase the scale of biodiversity loss, the report said. And biodiversity loss and climate change can create destructive feedback loops; when forests are cleared, for example, local climates get hotter and drier.

“The pressure we are placing on the natural world is driving an escalating nature crisis,” the authors wrote. “There is still time to act, but urgency is needed.”