Infinite blue to the horizon: the oceans appear to many as a mysterious expanse that has not been touched by humans. In fact, just 13 percent of the world’s oceans can still be described as wilderness. At least that is the result of a study reported by researchers in the journal Current Biology. According to them, marine wilderness is still mainly found in the Arctic and Antarctic and around remote Pacific overseas territories such as French Polynesia.
Wilderness is understood to be areas that are completely or virtually untouched by humans. “If you look at the North Sea on our doorstep, for example, we see a cultural landscape: every square meter is trawled several times a year,” says Thomas Brey, ecologist at the Alfred Wegener Institute in Bremerhaven and deputy director of the Helmholtz Institute for Functional Marine Biodiversity (HIFMB), from: “Wilderness is the opposite of that: in it nature does what it wants.” If humans intervene in such wilderness, the effects are often difficult to understand. “Wilderness is the system that has evolved to level off. If we change such functioning systems for our purposes, we usually don’t make them better, ”says Brey.
Such interventions in the ocean ecosystem have now been researched by the team led by environmental biologist Kendall Jones from the University of Queensland in Australia and the Wildlife Conservation Society (WCS). Because while the decline of wilderness on land has already been intensively investigated and documented, corresponding investigations for the oceans have not yet been carried out.
For their mapping of the world’s oceans, the scientists determined 19 man-made stress factors, so-called stressors. These included commercial shipping, the use of fertilizers and various types of fishing with all of their consequences. The researchers now identified areas that were exposed to very little human influence. They initially excluded climate change as a factor. Otherwise, the scientists write, they would not have found any more maritime wilderness.
The biologists then compared 16 oceanic areas to examine the respective effects of various stress factors. In doing so, they also included climate change again. They found big differences. In the warm Indo-Pacific, for example, only 16 million square kilometers of maritime wilderness remained – 8.6 percent of the ocean. In temperate southern Africa it is only 2,000 square kilometers. That is just one percent of the ocean. “We were surprised how little marine wildlife is left,” commented lead author Kendall Jones in a communication published on the study. “The oceans are huge and cover more than 70 percent of our planet, but we have managed to influence almost the entire ecosystem.”
In an independent classification, however, the ecologist Brey points out some of the difficulties of the study: “Such studies with global claims always have a data problem,” he explains. The data situation is different for different regions, so that there are gaps for the analysis. “These gaps are not addressed here,” says Brey. In addition, all stressors would be treated equally. One stressor is, for example, the development of the ocean floor. This does not necessarily have to be disadvantageous from an ecological point of view. Because, for example, “in offshore wind farms, fishing is not allowed, which is good, because fishing, especially bottom fishing, has the most serious effects on marine ecosystems,” explains the ecologist.
Another point: As the scientists criticize in their study, just five percent of the marine wilderness they have identified is under protection. In the list of marine protected areas (MPA), however, the Ross Sea in Antarctica, the largest MPA, is missing, as Thomas Brey notes. As part of the German delegation of the “Commission for the Conservation of Living Marine Resources of the Antarctic” (CCAMLR), he helped negotiate its establishment.
Despite these points of criticism in detail, Brey agrees with the results of the study: “The study may not be exact, but its statement is correct.” Such work is good for sustainable protection of marine wilderness. However, this does not work without political will: “We saw that with the Ross Sea: The MPA could only be set up when an agreement was found at the highest political level.”
Such negotiations, especially when it comes to international waters, however, needed time, since different political and economic interests would have to be reconciled – time that, according to the authors of the study, is running out. The risk that wilderness would be lost beforehand would also be increased by the fact that technical progress allows people to fish deeper and further out. In addition, there are the consequences of climate change, according to lead author Kendall Jones: “Thanks to a warmer climate, it is now even possible to fish in some places that were previously safe due to the year-round ice cover.”
The scientists concluded that international environmental agreements are now all the more important in order to recognize the unique value of marine wilderness and to set goals for their preservation. “We know that these areas are shrinking catastrophically, so protecting them must become a focus of multilateral environmental agreements,” urges James Watson, WCS director of science and biologist at the University of Queensland. The study’s co-author warns, “If that doesn’t happen, these wilderness areas will likely be gone within 50 years.”