“Nature Needs Half” — How to Protect the Earth, Support Indigenous Communities and Avert the Global Extinction Crisis

An exciting new study just came out that explores the opportunity to protect half of the world’s natural habitat and thus avert the current global extinction crisis — and the good news is that in most of the world this goal is still in reach.

Scientists, conservationists, lovers of wildlife (and plants, fungi and other life forms!) have been grappling for decades with the question of how to protect individual species and prevent the ongoing global species decline (i.e. extinctions) that has led many scientists to dub our current era Earth’s 6th Mass Extinction event. While we have had some success bringing back from the brink certain individual species (e.g. the bald eagle, California condor, southern white rhino), scientists and conservationists have overall been unable to prevent a much larger number of species from becoming threatened, endangered or going extinct. Biologist E.O. Wilson has compared the current global conservation movement to “a surgeon in an emergency room treating an accident victim: He has slowed the bleeding by half. Congratulations, we might say — even though the patient will be dead by morning.”

This might seem like an incredibly depressing scenario, except that now for the first time scientists are looking holistically at the problem and have put forth at least one solution to prevent the 6th Extinction Crisis — Half-Earth.

Half Earth” or “Nature Needs Half” is the scientifically-supported proposal that we must protect at least half of the world’s natural terrestrial habitat and 30-50% of the oceans in order to sustain upwards of 80% of the world’s species in the long termThe idea also recognizes that we need to acknowledge and support indigenous and local communities’ rights to own land and effectively manage large areas of natural habitat, because these communities are the best “sentinels” and stewards of ecosystems.

Protecting half of the Earth for nature and human beings’ sake is a great idea, but given that currently only 15% of the Earth’s land area is protected it also raises the question — but is this really possible?

The new Bioscience study shows geographically just how close we are to achieving this goal — and the most surprising finding is that for most of the world’s ecosystems this goal is in reach. Specifically, the study examined the world’s 846 “ecoregions,” and classified them according to how protected they are — resulting in this awesome interactive map. All four of the study’s categories are described below:

  • 98 ecoregions (11.6%) are already Half Protected
  • 313 ecoregions (37%) are classified as Nature Could Reach Half, i.e. 50% conservation hasn’t yet been achieved but could be achieved through additional protected areas (also natural habitats currently make up 50% or greater of their original range)
  • 228 (27%) are classified as Nature Could Recover, i.e. 20-50% of habitat is currently protected, so additional areas would have to be conserved and some natural regeneration of ecosystems would have to be supported
  • 207 (24%) are categorized as Nature Imperiled, or less than 20% of habitat area conserved

Global Map Half Protected with Legend

Above: A snapshot of the study’s interactive map. In addition to being organized by protected status (above), the map can also be organized by ecoregion or biome.


Above: Map of the world’s tropical rainforests (dark green) and subtropical rainforests (light green). Notice how many rainforests (but not all) fall in areas that are classified as “Nature Could Reach Half” or “Nature Could Recover” on the first map. Image by Ville Koistinen and copyrighted under Creative Commons BY-SA 3.0 license.

In terms of biodiversity, not all areas of the Earth are equal (although for spiritual, cultural and biological reasons it is important to conserve all parts of Earth).  Tropical forests are especially important to conserve because they contain an estimated 50% (or higher) of all terrestrial species on Earth. 76% of the world’s habitats are in the first, second or third categories and vast areas of tropical rainforest are in the second category of “Nature Could Reach Half” (and some in South America are “Already Half Protected”). Globally protected areas are currently increasing by about 4% per decade, so we will have to at least double this to 8 or 10% to achieve 50% protection of Earth’s natural habitat by 2050.

The Nature Imperiled category is particularly troubling because many of these areas overlap with the world’s biodiversity hotspots (e.g. the Guinean Forests of West Africa and the Indo-Burma hotspot), and the study found that on average only 4% of additional habitat exists outside of the current protected areas—so these areas will have considerable difficulty even reaching 20% protected status. The study also acknowledges that the most endangered areas of high biodiversity are tropical dry forests followed by tropical grasslands (e.g. Brazil’s famous Cerrado) and Mediterranean forests.

Finally, the study’s lead author has a blog post (which you can find in the Mongabay article) outlining his vision of “Nature Needs Half,” which is quite similar to E.O. Wilson’s “Half-Earth”. One important component of both is that respect and recognition of indigenous communities’ rights and land claims will contribute towards protection of nature rather than take away from it. Indeed, recently scientific studies have shown that indigenous communities are highly effective protectors and stewards of the world’s forests, but there is a “catastrophic failure” of governments to recognize the lands of indigenous peoples. In terms of environmental protection, having the buy-in and partnerships with local communities is just as (or more) important than the latest technologies to monitor the world’s forests and oceans (e.g.Global Forest Watch and Global Fishing Watch).

This all points in a single direction: for the first time in human history, we have the technology, the convergence of the global movements for indigenous rights and environmental protection and the scientifically-grounded understanding of the need to protect large habitat areas that could sustain our Earth and all its life in the long term. The only question is, will we organize ourselves to do it?

Urubamba_RiverAbove: View from Wayna Picchu Peak. Tropical forests contain over 50% of the world’s terrestrial biodiversity and it is crucial to protect their habitat. Photo by Mariano Mantel and copyrighted under Creative Commons (CC BY-NC 2.0).

Cover image: Morning mist over the Amazon rainforest. Photo by Fabrice Marr and copyrighted under Creative Commons.


Dinerstein, E., Olson, D., Joshi, A., Vynne, C., Burgess, N. D., Wikramanayake, E., … & Hansen, M. An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm. BioScience. 14 April 2017.

2 thoughts on ““Nature Needs Half” — How to Protect the Earth, Support Indigenous Communities and Avert the Global Extinction Crisis

Add yours

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s


Up ↑

%d bloggers like this: