At the beginning of the 20th century, the world human population was about 4 times smaller than today. Although many ecosystems in the heavily populated areas faced severe pressures even then, there were still vast tracts of land that had thrived undisturbed. Only 15% of Earth’s surface was used to grow crops and raise livestock.
How has the situation changed over the last one hundred years?
An international group of scientists led by James E. M. Watson and James R. Allan mapped the world’s remaining terrestrial wilderness in 2016. In 2018, they completed their work by producing a map of intact ocean ecosystems.
To do the mapping, Watson and his team utilized the best available data (collected in 2009) on eight indicators of human pressures – built environments, croplands, pasture lands, population density, railways, major roadways, navigable waterways, and night-time lights – at a resolution of 1 square kilometer. For mapping the ocean ecosystems, they used 2013 data on 16 indicators including fishing, industrial shipping, and fertilizer run-off. Besides being free of anthropogenic pressures, the areas considered have a contiguous area of more than 10,000 square kilometers.
How much of the wild is left on Earth?
The team came to some stunning figures: “Today, more than 77% of the land(excluding Antarctica) and 87% of the ocean has been modified by the direct effects of human activities”.
If we invert the numbers to get a clearer picture, it means that only 23% of land and a 13% of oceanscan still be considered undegraded truly “wild”.
Considering that humans have existed for some 200.000 years, it is easy to see the rate of change is extremely quick – and accelerating. The authors point out that only between 1993 and 2009, 3.3 million square kilometersof terrestrial wild land was lost to human settlement, farming, mining, or other pressures.
Interestingly, excluding the high seas and Antarctica, it turned out that only20 countries contain 94% of the world’s remaining wilderness,withmore than 70%in just five countries — Russia, Canada, Australia, the United States, and Brazil, respectively.
The study excludes Antarctica, the only “untouched” continent – by an international treaty, Antarctica is claimed by no country, and international scientific research is largely the only activities that are conducted on the icy continent. However, Antarctica is still degraded by climate change, pollution, and invasive species, and if the ice melt continues, there are fears that Antarctica might be targeted for its oil reserves sometime in the future.
Consequences of wilderness loss
In the light of the figures presented by the study, we can easily understand how human activity has shrunk wildlife populations by 60% in just 50 years. The loss of wilderness is a huge issue not only because of biodiversity loss but also because of the way it is affecting our climate. Besides analyzing the data on land cover, in the comment on their results Watson et al look at the broader environmental importance of wilderness.
Although the team acknowledges the significance of fragmented ecosystems that provide valuable services to both wildlife and humans, they point out that it is the undisturbed ecosystems that have a crucial role in regulating many of the Earth’s mechanisms. For example, intact forests can sequester and store much more carbon than degraded forests; on the other hand, logging and burning account for 40% of total above-ground emissions in the tropics.
Wild ecosystems are also much more resilient to climate change. The authors quote a 2009 study which showed that Caribbean coral reefs that are exposed to low human pressures have recovered from coral bleaching up to four times faster than did reefs that faced higher levels of pressures.
Solutions to wilderness crisis
Towards the end of the discussion, Watson and his team consider solutions and mechanisms which would help protect the remaining wilderness. They suggest that efficient conservation possible only if the importance of pristine ecosystems is recognized within the international policy frameworks. Also, the team sees the protection the human indigenous populations as a good model for conserving the ecosystems they inhabit along the way.
Considering the small number of countries containing the remaining wild ecosystems, the way individual countries handle these areas is critically important. One of the issues is that in most states, “wilderness” is not formally defined and specially protected. Ironically, in this sensitive moment, two out of five countries containing more than 70% of wilderness – the United States and Brazil– have started conducting anti-conservation policies with more promises of “opening up” more wild land for exploitation.
In the period when economic and even political pressures on the last of the wild seem to be ever-growing, integrating human activity with natural ecosystems in a sustainable way is often seen as a needed compromise. However, this paper and the author’s remarks remind us that we have to be careful when making those compromises because nothing can compensate for the value and the services of intact ecosystems. The international community needs to make an effort to protect them.
The study (comment):
Watson et al. 2018. “Protect the last of the wild”. Nature. October 31, 2018. https://www.nature.com/articles/d41586-018-07183-6
“It’s up to five countries to save all of Earth’s wilderness”. The Weather Network. November 9, 2018 https://www.theweathernetwork.com/news/articles/earths-wilderness-is-vanishing-and-just-a-handful-of-nations-can-save-it-brazil-amazon-antarctica-north-america/116659
“Human Pressures Have Shrunk Wildlife Populations by 60 Percent”. Scientific American. October 31, 2018. https://www.scientificamerican.com/article/human-pressures-have-shrunk-wildlife-populations-by-60-percent/