Joris Cromsigt

Large parts of our planet are facing a dramatic loss of the world’s last wild megafauna (mammalian herbivores and carnivores > 40kgs), a process that is also referred to as defaunation. In contrast, parts of particularly the northern hemisphere experience a megafaunal rewilding and see populations of large carnivores and herbivores increase. Defaunation and rewilding may both have huge consequences for the sustainable functioning of socio-ecological systems. My team and I study the patterns and processes of defaunation and rewilding and the consequences for sustainable functioning of ecosystems as well as human society. We study systems all over the world, with a special focus on Southern Africa and Europe.

Defaunation & Sustainability
We explore a broad diversity of the consequences of megafaunal loss ranging from biogeochemistry, to fire regimes, and climate-vegetation feedbacks. As an example of a project in this theme, I lead the HOTSPOT program, which focuses on the white rhino poaching crisis in Hluhluwe-iMfolozi Park, South Africa. The program has two main objectives: (1) increasing our understanding of white rhino movement patterns and population ecology and (2) investigating the ecological effects of losing white rhino.

Rewilding & Sustainability
Rewilding occurs passively (comeback of species without direct human intervention) or through active (re)introductions of large mammals. The aim of active rewilding is to mitigate effects of global change (such as biodiversity loss) and restore top-down trophic interactions and associated ecosystem structure and functioning. In a variety of projects across Europe and southern Africa, we study the consequences of rewilding for biodiversity, ecosystems, earth system functioning and human well-being.

One example of this is the Wilder Rangelands program through which we investigate if and how the restoration of natural processes, such as fire and mammalian herbivory, in rangelands (grassy ecosystems that are grazed by large mammalian herbivores) may lead to win-win situations for climate change mitigation, biodiversity restoration and human livelihoods.

Human-wildlife coexistence

The coexistence between humans and wildlife is a core theme for both finding opportunities to reduce defaunation as well as managing the consequences of successful rewilding. Finding ways to promote coexistence of humans and wildlife, benefitting the well-being of both, is therefore a key focus of our work as well. A prime example of this work is our transdisciplinary research program WildlifeNL, where we work with a big consortium of academic and non-academic partners to analyze the wildlife comeback and opportunities to faciliate human-wildlife coexistence in the Netherlands. 

I teach in a variety of courses at both MSc and PhD level on a wide range of topics, including trophic ecology, megafaunal ecology, conservation biology, adaptive wildlife management and experimental design.