Space use of a diverse megafauna community in a rewilding area in the southwestern Carpathians

Abstract

Most landscapes today have lost much of their historical biodiversity, particularly the largest animals (mega-fauna). Yet, in some regions declining human pressure and stronger conservation policies allow megafauna to return, and rewilding efforts sometimes seek to amplify these trends through reintroductions. Megafauna, however, return to landscapes still inhabited and used by people, making it crucial to understand how they adapt to such shared landscapes. Here, we studied the space use of a uniquely diverse megafauna community, including recently reintroduced European bison, in a rewilding area in the Romanian Carpathians. We conducted extensive sign surveys (2688 km) to monitor eight large mammals in 2022 and 2023. We then applied Bayesian occupancy models to understand the space use of our target species. Our results show that landscape composition is important for allowing a diverse megafauna community to share space with people. Many species (e.g., red deer, roe deer, grey wolf, brown bear) used different forms of refuge habitat (i.e., topographically complex areas, dense forest) to avoid people. Only one species, the European bison, appeared to be negatively affected by direct human pressure (i.e., active logging). Conversely, land-use legacies such as forest gaps and abandoned pastures were selected by most species (i.e., European bison, red deer, roe deer, wild boar, brown bear). Our study shows that diverse megafauna, including the largest species, can share space with people in mosaic landscapes. These landscapes, especially if human pressure is declining, offer major opportunities to protect megafauna and restore their ecological roles, in Europe and elsewhere.