Protected area personnel and ranger numbers are insufficient to deliver global expectations

Abstract The 2020 global spatial targets for protected areas set by the Convention on Biological Diversity have almost been achieved, but management effectiveness remains deficient. Personnel shortages are widely cited as major contributing factors not previously quantified. Using data from 176 countries and territories, we estimate a current maximum of 555,000 terrestrial area personnel worldwide (one per 37 km 2 ), including 286,000 rangers 72 far short published guidance required densities. Expansion 2030 to 30% coverage other effective area-based conservation measures is agreed minimum safeguarding biodiversity ecosystem services. We project that this expanded system will require approximately 3 million 13 more than 1.5 or equivalents 26 ). Parallel improvements in resourcing, working conditions capacity effective, equitable sustainable management.