10 Percent of the World’s Wilderness Has Disappeared in Just 20 Years

For the first time, scientists have mapped out the destruction of wilderness areas around the globe, finding a staggering loss over the past 20 years.

Ten percent of the world’s wilderness has disappeared since the 1990s, with the Amazon losing 30 percent and Central Africa 14 percent of wildlands, according to a study published Thursday in the journal Current Biology.

Researchers found that more than 2 million square miles of wilderness have been wiped out.

To reach those sobering conclusions, the researchers created a map of all wilderness areas in the world today and compared it with a comparable map from the 1990s.

“It’s the first assessment to measure such change over time, and it was staggering to find that an area twice the size of Alaska has been cleared in 20 years,” said lead author James Watson of the University of Queensland in Australia and the Wildlife Conservation Society in New York.

“To lose 10 percent of all wilderness in just 20 years is just unbelievable, because if you follow that logic through, there will be no wilderness left in 50 years,” he said. “We probably have one to two decades to turn this around.”

Wilderness destruction has different causes. “You have rapid urbanization and agriculture in many places, large-scale logging in the Amazon and Central Africa, and palm oil expansion in Asia,” Watson said.

Other causes include climate change, wildfires, roads, mining, and fossil fuel extraction.

What can be done? The researchers offered a list of recommendations, such as intervening now in pristine areas where development is planned, establishing “mega-conservation corridors” between protected areas, and making payments for ecosystem services in recognition of their economic benefits, “such as being a secure source of fresh water, reducing disaster risks, and storing large carbon stocks.”

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About 23 percent of the world’s landmass remains as wilderness, and about four-fifths of that lies in contiguous areas larger than 6,200 square miles, which are considered “globally significant wilderness blocks.”

“Yet there was substantial erosion of these large wilderness areas over the past two decades,” the authors wrote, with losses amounting to 1.7 million square miles. Of the 350 wilderness blocks present in the early 1990s, thirty-seven are no longer globally significant, and 74 percent experienced some form of erosion.

International efforts to conserve wildlands have not kept up with the steady clip of destruction. In the last 20 years, 1.6 million square miles of wilderness were newly protected, but 2 million were lost, the study reported.

That rapid loss is contributing to climate change and species depletion, according to scientists.

The remaining wilderness on Earth contains more carbon dioxide than the world’s oil, gas, coal, or atmosphere, and “protecting the globally significant wilderness areas...will make a significant contribution to stabilizing atmospheric concentrations of CO2,” the authors wrote.

Meanwhile, the geographic ranges of one-third of all land mammals overlap with remaining significant wilderness areas. Rapid destruction “increases the risk of extinction for species that are already highly threatened,” the paper said.

Nick Haddad, a professor of applied ecology at North Carolina State University who studies habitat loss but did not participate in the study, said destroyed wilderness can never be restored.

“Forests and grasslands can return but not wilderness,” he said. “It’s almost impossible to envision a scenario to make that happen. It would take an incredible amount of time or active restoration that would never happen at this scale.”

Kierán Suckling, executive director of the Center for Biological Diversity, called the findings “shocking and heartbreaking, and that’s coming from someone who spent the last 30 years working in wilderness preservation but has not been able to have quantified just how much is being lost.”

“I suspect that the wilderness we do not protect in the next 10 or 20 years is probably never going to be protected, so this really is the challenge of our generation,” he added. “We are in a position now where either everything is going to be protected or it will be gone.”