Megafauna restoration as a legal obligation: International biodiversity law and the rehabilitation of large mammals in Europe

Restoring functional ecosystems in Europe inter alia requires restoring large mammal (megafauna) diversity and densities to levels well above the current downgraded state, which results from a human-driven wave of megafauna extinctions and extirpations in the Late Pleistocene and Holocene. Combining law and natural science, we address the question to what degrees international legal instruments support or require such megafauna rewilding efforts. We provide an overview of Europe's current megafauna plus those species that would likely have been present without human interference. We categorize these species and restoration scenarios in ways that make sense from a legal perspective and identify and interpret relevant legal instruments. Our analysis indicates that Article 8(f) of the Convention on Biological Diversity requires restoring the diversity and densities of Europe's megafauna as far as possible—which is indeed quite far. Depending on the circumstances, megafauna rewilding measures can also be required or supported by various other legal instruments at global, pan-European, European Union and other levels.