Just 13 percent of the world’s oceans can still be classified as wilderness because of man’s interference, new research warns.
The first mapping of global marine wilderness has shown just how little remains.
Researchers have completed the first systematic analysis of marine wilderness around the world.
And they said that what they found is not encouraging: only around an eighth – about 13 percent – of the world’s ocean can still be classified as wilderness.
Their findings, published in the journal Current Biology, also show that the remaining marine wilderness is unequally distributed and found primarily in the Arctic, in the Antarctic, or around remotest parts of the south Pacific ocean.
In coastal regions, there is almost no marine wilderness left at all.
Study co-author Kendall Jones, a PhD candidate at the University of Queensland in Australia and the Wildlife Conservation Society, said: “We were astonished by just how little marine wilderness remains.”
“The ocean is immense, covering over 70 percent of our planet, but we’ve managed to significantly impact almost all of this vast ecosystem.”
On land, rapid declines in the wilderness have already been well documented.
But much less was known about the status of marine wilderness, even though wilderness areas are crucial for marine biodiversity.
Jones said: “Pristine wilderness areas hold massive levels of biodiversity and endemic species and are some of the last places of Earth where big populations of apex predators are still found.”
For the new study, researchers used the most comprehensive global figures available for 19 human “stressors” including commercial shipping, fertilizer and sediment run-off, several types of fishing in the ocean, and their cumulative impact.
They systematically mapped marine wilderness globally by identifying areas with very little impact — the lowest 10 percent — from 15 anthropogenic stressors and also a very low combined cumulative impact from the stressors.
To capture differences in human influence by ocean regions, the researchers repeated their analysis within each of the 16 ocean areas.
They found wide variation in the degree of human impacts. For example, around 6.2 million square miles of wilderness remains in the Indo-Pacific ocean, accounting for just 8.6 percent of the ocean.
But it’s even worse in southern Africa, where less than 770 square miles of marine wilderness remains — less than one percent of the ocean.
The study also shows that less than five percent of global marine wilderness is currently protected.
Most of that is in offshore ecosystems, with very little protected wilderness found in high-biodiversity areas such as coral reefs.
Jones added: “This means the vast majority of marine wilderness could be lost at any time, as improvements in technology allow us to fish deeper and ship farther than ever before.”
“Thanks to a warming climate, even some places that were once safe due to year-round ice cover can now be fished.”
The research team said their findings highlight an “urgent need” for action to protect what remains of marine wilderness.
They said such an effort requires international environmental agreements to recognize the “unique value” of marine wilderness and sets targets for its retention.