Only 23% of the world's landmass can now be considered wilderness -- and scientists are calling it a 'horror story'

Brazil’s new leader wants to build a highway through the Amazon. Picture: Getty Images

  • Study maps the world’s landmass and ocean wildernesses for the first time.
  • In 100 years, human activity has modified up to 87% of wilderness areas, up from 15%.
  • Just five countries — including Australia — are now responsible for 70% of the planet’s remaining wilderness areas.

Just 23% of the world’s landmass can now be considered “wilderness”.

Writing in the journal Nature, conservation scientists describe wilderness areas as those places that do not have industrial level activity within them according to the marine and terrestrial human footprint.

Numerous recent studies say such areas are crucial as buffers against the effects of climate change and other human impacts.

The authors discovered the 23% figure after compiling the first comprehensive fine-scale map of the world’s remaining marine and terrestrial wild places.

And once they’re gone, wilderness areas don’t grow back.

“These results are nothing short of a horror story for the planet’s last wild places,” lead author James Watson says from the University of Queensland and the Wildlife Conservation Society said.

“The loss of wilderness must be treated in the same way we treat extinction. There is no reversing once the first cut enters.

“The decision is forever.”

And Australia has emerged as one of the world’s final hopes to save it.

The study found that just 20 nations hold 94% of the world’s marine and terrestrial wilderness areas (excluding Antarctica and the High Seas). Five “mega wilderness” nations contain 70% — Russia, Canada, Australia, United States and Brazil.

The authors argue that these nations have an enormous role to play to secure the last of the wild.

This week, scientists became even more worried that one of those countries, Brazil, cannot be relied on, after the election of new far-right presidential candidate Jair Bolsonaro.

Bolsonaro has said he’s thinking about opening up a highway through the Amazon and barring environmental non-governmental organisations like Greenpeace and the World Wildlife Fund from the country.

What’s your dinner doing to the planet? Picture: Getty Images

To map global wilderness, the team used data on eight indicators of human pressures — built environments, crop lands, pasture lands, population density, night-time lights, railways, major roadways and navigable waterways.

Oceans ecosystems were mapped using 16 data points, including fishing, industrial shipping and fertiliser run-off.

“Wilderness land or ocean areas” was identified as free of human pressures, with a contiguous area of more than 10,000 km2 on land.

Various analyses reveal that wilderness areas provide important refuges for species in decline, and marine wildernesses are the last regions that still contain viable populations of top predators, such as tuna, marlins and sharks.

The Nature story on the report noted that 100 years ago, just 15% of the Earth’s surface was under farmland. Today, “more than 77% of land (excluding Antarctica) and 87% of the ocean has been modified by the direct effects of human activities”.

Wilderness areas also store enormous amounts of carbon in intact ecosystems which are at least twice as important as similar degraded habitats when it comes carbon mitigation.

And many wildernesses are home to millions of indigenous people who rely on them for maintaining their long connections to land and sea.

John Robinson, WCS Executive Vice President for Global Conservation and paper co-author, said wilderness will only be secured if Australia and the other leading nations take a leadership role.

“Right now, across the board, this type of leadership is missing,” he said. “Already we have lost so much.

“We must grasp these opportunities to secure the wilderness before it disappears forever.”

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