PLATEAUED POTENTIAL: Prioritizing Land for Species Preservation

Amidst an alarming surge in global habitat destruction and species extinctions, new research published today by scientists at The Nature Conservancy (TNC) and ten collaborating institutions proposes a new global approach to choosing protected lands which could reduce species extinction risk twice as efficiently as current methods.

Protecting key ecosystems and habitats is widely accepted as being one of the most powerful tools against species extinction. However, a point of contention arises when trying to calculate ecological value and decide which lands are prioritized for protection first, in order to provide maximum benefit to the greatest number of at-risk species globally. This study argues that current land prioritization practices fall short, excluding localized data fundamental to understanding how a species interacts with the habitats in its global distribution.

“The global extinction of a species begins locally, occurring one population at a time, and individual populations can be more or less resilient depending on regional factors like land usage or management intensity,” explains lead author Nicholas Wolff, Director of Climate Science at TNC. “We need a prioritization model that reflects those core tenets of ecology.”

The coalition of researchers sought to prove there was a better and more effective approach that governments and practitioners allocating lands for conservation could use in the future. Rather than determine land prioritization based solely on species range and richness – as has historically been the case – the study modeled what would happen if conservationists also incorporated population-level info, such as the growth rates and habitat needs of every individual population of a species.

The results were eye-opening, showing that 92% of the planet’s ‘priority habitats for persistence’ – the lands, in other words, that at-risk mammals depend upon most for their survival – are not currently under strict protection.

“To our knowledge, this is the first study where the identified priority areas maximize not just global biodiversity representation, but also persistence at this spatial scale and detail,” adds Heini Kujala, co-author and University Researcher at the Finnish Natural History Museum. “We hope the findings encourage innovation in conservation strategies worldwide, contributing to the global fightback against accelerating extinctions rates.”

The study, published today in One Earth, identified a number of habitats where strengthening existing conservation protections has potential to bring about a significant reduction in global extinction risk for a greater number of species. Notably, they found that just seven countries – Australia, Brazil, China, Indonesia, Madagascar, Mexico and Papua New Guinea – contain over half of Earth’s surviving priority habitats for species persistence, providing ample potential for trialing the new approach proposed by this study.

The results are already being put to use at TNC, helping pinpoint “Last Chance Ecosystems,” prioritize conservation focal areas, and inform strategy organization-wide.

The paper was published just one month shy of the first anniversary of the UN’s Kunming-Montreal Global Biodiversity Framework (GBF), which included ambitious commitments to both protect 30% of the world’s lands by 2030 and halt human-induced extinction of threatened species by 2050.

“There is currently a gap between the biodiversity targets the international community has committed to and the current scale of global conservation," says senior author Eddie Game, senior lead scientist at TNC.  "This research will hopefully enable nations to reach their conservation targets faster and curb declines in their native mammal species populations more effectively, getting us one step closer to closing the gap and achieving the ambitious targets set by the United Nations in the GBF.” 

The study was authored in collaboration with scientists from TNC, IIASA, University of Helsinki, CNR-IRET, Radboud University, Zoological Society of London (ZSL), University College London, University of Melbourne, Sapienza University of Rome, and the University of Queensland. The full paper is available here: https://www.cell.com/one-earth/fulltext/S2590-3322(23)00451-7

Wolff, N., Visconti, P., Kujala, H., Santini, L., Hilbers, J., Possingham, H., Oakleaf, J., Kennedy, C., Kiesecker, J., Fargione, J., & Game, E. (2023). Prioritizing global land protection for population persistence can double the efficiency of habitat protection for reducing mammal extinction risk. One Earth. 

DOI: https://doi.org/10.1016/j.oneear.2023.10.001