Current ecological decline is unprecedented and, along with the disruption of climate systems, threatens the well-being of billions of people. The primary driver of biodiversity loss is habitat loss and degradation through land/sea use conversion, and overexploitation (particularly oceanic). This motion is based on the best available scientific evidence that a minimum of 30% and up to 70% or more of earth’s land and sea must be protected and restored in an interconnected way, nested within sustainably managed land and seascapes, to reverse biodiversity decline, maintain and restore ecosystem integrity, and stabilize the climate. Conserving half or more of earth is supported by many scientific studies (see below).
A large evidence-based percentage goal is important to drive progress at scale; however, implementation must also focus on quality to achieve conservation outcomes. The motion calls on governments to prioritize conservation of areas important for biodiversity and ecosystem services, with high levels of integrity (ie. intact wilderness), ecological connectivity, and culturally significant natural areas identified by Indigenous peoples.
A global goal of protecting half must recognize regional realities. Eg. heavily settled regions do not have enough intact nature left to protect half. These regions should focus on protecting remaining fragments of nature and restoring interconnected habitat. In other regions, such as the Amazon, much more than half the ecosystem needs protecting to prevent a “regime shift” from rainforest to savannah. Globally, the % target for land and sea protected should be about half or more to safeguard life on earth.
Public opinion polls around the world show strong support. An 8 country study found that citizens support protecting about half the earth.

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Locke 2013. Nature Needs Half: A necessary and hopeful new agenda for protected areas. Parks 19(2): 13-22. DOI: 10.2305/IUCN.CH.2013.PARKS-19-2.HL.en.
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ZSL 2014 “Space for Nature” survey: https://www.zsl.org/conservation/news/planet%E2%80%99s-protected-areas-fall-short-of-public%E2%80%99s-expectations

• Australian Rainforest Conservation Society [Australia]
• Canadian Parks and Wilderness Society [Canada]
• Eco Foundation Global [China]
• Fundación para la Conservación del Bosque Chiquitano [Bolivia]
• The WILD Foundation [United States of America]
• Wilderness Foundation [South Africa]
• Wildlife Conservation Trust [India]
• Yellowstone to Yukon Conservation Initiative [United States of America]