The world's wilderness areas, where human impact is absent or minimal, halve the extinction risk of biodiversity compared to areas outside wilderness, according to a new Nature journal paper.
The paper , released globally today, reveals that wilderness areas are important because they host highly unique biological communities, and represent most of the remaining natural habitats for species that have suffered high levels of habitat loss elsewhere.
Researchers from Australia's lead science agency CSIRO and the University of Queensland found that wilderness areas act as a buffer against extinction risk in the first ever assessment of the global importance of wilderness areas for the persistence of terrestrial biodiversity.
"Wilderness areas act as a buffer against extinction risk, so the risk of species loss is over twice as high for biological communities found outside wilderness areas," CSIRO scientist and lead author Dr Moreno Di Marco said.
"This is important because reducing the rate of global biodiversity loss is a major challenge facing humanity, but little is known about the role that remaining wilderness areas have in mitigating the global biodiversity crisis.
"The latest maps show that more than three million square kilometres of wilderness has been lost since the 1990s, which is an area the size of India, and less than 20 per cent of the world can be called wilderness.
"Yet until now, little was known about the consequences of this for preventing extinction of species."
The research collaboration took advantage of CSIRO's global biodiversity modelling capability BILBI, which provides fine-scale estimates of the probability of species loss around the globe, CSIRO scientist and co-author Dr Simon Ferrier said.
This capability was integrated with the latest wilderness mapping generated by the University of Queensland, the Wilderness Conservation Society and the University of Northern British Columbia to demonstrate that today many wilderness areas are critical to prevent the loss of terrestrial species in many areas of the world.
The research found wilderness habitat makes an even larger contribution, as some species can occur both inside and outside wilderness; this habitat is essential to support the persistence of many species that otherwise live in degraded environmental conditions in many regions.
Some wilderness areas play an extraordinary role in safeguarding biodiversity.
These areas include parts of the Arnhem Land in Australia, which is covered by several Indigenous Protected Areas, areas surrounding the Madidi National Park in the Bolivian Amazon, forests in southern British Columbia (which are only in part protected), and Savannah areas inside and outside the Zemongo reserve in the Central African Republic.
"It is essential that highly irreplaceable wilderness habitat is preserved if we want to prevent, rather than react to, future biodiversity loss," Dr Di Marco said.
