We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature—a companion to the Paris Climate Deal—to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.

The Global Deal for Nature (GDN) is a time-bound, science-driven plan to save the diversity and abundance of life on Earth. Pairing the GDN and the Paris Climate Agreement would avoid catastrophic climate change, conserve species, and secure essential ecosystem services. New findings give urgency to this union: Less than half of the terrestrial realm is intact, yet conserving all native ecosystems—coupled with energy transition measures—will be required to remain below a 1.5°C rise in average global temperature. The GDN targets 30% of Earth to be formally protected and an additional 20% designated as climate stabilization areas, by 2030, to stay below 1.5°C. We highlight the 67% of terrestrial ecoregions that can meet 30% protection, thereby reducing extinction threats and carbon emissions from natural reservoirs. Freshwater and marine targets included here extend the GDN to all realms and provide a pathway to ensuring a more livable biosphere.

Elephants (Loxodonta africana) raiding crops around Tanzanian national parks threaten farmers' lives and livelihoods, thus contributing to negative local attitudes towards wildlife. As a result, there is often tacit support for poaching among local communities, and elephants suffer through reprisal poisoning or wounding or through being shot as 'problem animals' by game wardens. Human-elephant conflict (HEC) is growing as the wildlands that still have elephants, especially around national parks, reserves, and wildlife corridors, are increasingly being settled. Sisal string fences soaked in engine oil mixed with ground chili (Capsicum spp.) can dissuade elephants from entering fenced fields. For the last nine years, farmers around Mikumi National Park in Tanzania have been constructing these fences around ripening crops, and there have been no incidents of fences being broken by elephants. Community-based organizations (CBOs) that manage members' savings through village micro-credit associations help ensure the costs of materials and fence construction are met. Chili fences are rapidly becoming widespread, facilitated through farmer-to-farmer exchanges where teams of farmers demonstrate both the fences and the CBOs needed to support the project. We argue that promoting the use of chili fences, coupled with supporting CBOs, as a best practice within communities and government programs and budgets, will help reduce the need for HEC compensation, protect livelihoods, empower rural women, increase the food security of rural farmers, and help conserve elephants.

Real-time forest monitoring technologies could help track changes in tiger populations.