With each passing year, the world has fewer and fewer pristine natural spots, as cities, roads, farms, mines, logging, and other industrial activities have pushed into nearly every corner of the planet.
A new study in Current Biology reports that Earth has lost 10 percent of its wilderness since the early 1990s — an area twice the size of Alaska. "The amount of wilderness loss in just two decades is staggering and very saddening," said lead author James Watson of the University of Queensland. Here’s the damage:
The study defines "wilderness" as "biologically and ecologically largely intact landscapes that are mostly free of human disturbance." That includes largely untouched forests, grasslands, savannahs, and swamps. (Notably, a wilderness doesn’t have to be entirely free of people; some rainforests with indigenous communities living in them still count.)
The big picture here is stunning: In all, we've lost roughly 1.2 million square miles of wilderness since the early 1990s, leaving 12 million square miles still intact.
Losses have been especially heavy in the Amazon and central Africa. A few areas have lost nearly all of their former wilderness, including the Northwestern Congolian Lowland Forests and the Northern New Guinea Lowland Rain and Freshwater Swamp Forests ecoregions.
On the bright side, there’s at least some hope of abating further losses. Throughout the 1990s in Brazil, farmers burned vast swaths of rainforest to make space for cattle and crops. But between 2005 and 2012, deforestation rates fell 70 percent thanks to new protections and efforts by Brazil's cattle ranchers and soybean farmers to intensify production on the land they’d already cleared. It was one of the greatest environmental success stories ever. Still, it wasn't airtight. In the past few years, deforestation in Brazil has starting ticking up again, particularly among small farmers — and there's evidence that forest loss has accelerated in nearby Peru and Bolivia.
The Current Biology study also reported some positive news: Much of the remaining wilderness, about 80 percent, still consists of large, contiguous chunks of land. That’s crucial for the species living there: If habitats get too fragmented by roads or clear-cutting, animals become much less likely to survive. (Last year, I talked with Duke biologist Stuart Pimm, who was engaged in an effort to stitch together fragmented forests in Brazil in order to save species like the golden lion tamarin.)
Still, it’s clear a lot more is needed to protect the remaining wilderness. Some of that involves basic conservation, turning vulnerable forests and grasslands into protected areas and reserves — particularly the most ecologically valuable or irreplaceable areas. But this will also require shrinking humanity's land footprint, so that we don't need to keep encroaching on wilderness forever. That might entail using substitutes for certain raw materials such as wood or by increasing crop yields on existing farmland so that we don't need as much space.
There are some indications that we humans are starting to do exactly that, using technology and ingenuity to shrivel our environmental impact even as living standards keep rising. See this 2015 report, "Nature Unbound: Decoupling for Conservation," led by Linus Blomqvist of the Breakthrough Institute, for much more on these hopeful trends.
And what about the wilderness that has vanished? Some experts would say that it's gone forever: "You cannot restore wilderness," said Watson in a press release. "Once it is gone, the ecological process that underpin these ecosystems are gone, and it never comes back to the state it was. The only option is to proactively protect what is left." Others would argue that it's worth trying to restore and revive damaged ecosystems, returning them to some semblance of their former shape: See Katherine Rowland's great piece in the Guardian for more on that.