The world has lost wilderness over the past 20 years that is roughly twice the size of Alaska, or 10% of the world’s total. The report’s results were published in Current Biology.
The primary point of the conclusion:
(researchers) demonstrate alarming losses comprising a tenth of global wilderness since the 1990s – an area twice the size of Alaska and half the size of the Amazon. The Amazon and Central Africa have been hardest hit.
The losses where fairly concentrated, based on maps of the erosion:
This comparison showed that a total of 30.1 million km2 (around 20 percent of the world’s land area) now remains as wilderness, with the majority being located in North America, North Asia, North Africa, and the Australian continent. However, comparisons between the two maps show that an estimated 3.3 million km2 (almost 10 percent) of wilderness area has been lost in the intervening years. Those losses have occurred primarily in South America, which has experienced a 30 percent decline in wilderness, and Africa, which has experienced a 14 percent loss.
Commenting on the results, Dr. James Watson of the University of Queensland in Australia and the Wildlife Conservation Society in New York said:
Globally important wilderness areas—despite being strongholds for endangered biodiversity, for buffering and regulating local climates, and for supporting many of the world’s most politically and economically marginalized communities—are completely ignored in environmental policy.Without any policies to protect these areas, they are falling victim to widespread development. We probably have one to two decades to turn this around. International policy mechanisms must recognize the actions needed to maintain wilderness areas before it is too late. We probably have one to two decades to turn this around.