Only 23% of the Earth Can Be Considered "Wilderness," Warns Biologist

Human world domination is almost complete, warn scientists in a new Nature article, and that’s not a good thing. For most of the Earth’s 4.5-billion-year existence, the vast majority of the land has been considered “wild” — untouched and unsullied by human hands. But new maps created by a team of conservation biologists reveal how little wilderness is left, and how dangerous its loss could be.

James Watson, Ph.D., is a conservation biologist at the University of Queensland and the first author of the commentary article, where he and his colleagues establish how much has changed in the past hundred years. “A century ago, only 15% of Earth’s surface was used to grow crops and raise livestock,” they write. Today, that fraction has jumped to 77 percent.

According to Watson and his colleagues, only 23 percent of the world’s land surface (excluding Antarctica) can be considered wilderness. “They are still wild because no industry has got there,” he tells Inverse. “[Human] population growth has led to industrial expansion and hence wilderness lost.”

In a recent, related study, the team determined how much of the ocean could still be considered wild, estimating that 87 percent of the Earth’s waters had already been modified by human activity. For both their terrestrial and aquatic measurements, they used existing data sets representing human presence (like population density and night-time lights for land, and fishing and industrial shipping in the ocean) to examine world maps at a resolution of 0.39 square miles (one square kilometer). They define wilderness as regions “free of human pressures, with a contiguous area of more than 10,000 [square kilometers] on land.”

Conserving the Earth’s remaining wild areas isn’t just geared toward preserving the unique biodiversity of those areas, though that of course is a priority. These regions are home to the Earth’s last indigenous peoples, groups that already poor and marginalized. Furthermore, the loss of wilderness areas will make it even more difficult to mitigate the changing climate. Boreal forests in Canada and Russia, for example, hold almost one-third of the Earth’s carbon. Disrupting them could release those ancient stores, exacerbating the already-dire levels of greenhouse gases in the atmosphere.

The maps show that a lot has changed, even in the short period between 1993 and 2009. During that time, the team reports, a region of wilderness the size of India — about 1.3 million square miles (or 3.3 million square kilometers) — was lost to human influence. Protecting what’s left of the Earth’s wild areas, Watson explains in the video, will require the cooperation of the nations that encompass those regions.

For better or for worse, the regions are concentrated in just a few countries. According to the team, 20 countries are responsible for a staggering 94 percent of the remaining wilderness. More than 70 percent of that is concentrated in five (large) countries: Russia, Canada, Australia, the United States, and Brazil.

“They desperately need to take leadership to conserve those places,” Watson says in the video. Unfortunately, the US has not been setting a good precedent as of late: In late 2017, President Donald Trump threatened to scale back the borders of many national parks to make way for mining, logging, and oil and gas drilling — a dangerous move, considering American parks are already bearing the brunt of the effects of climate change.