Context matters when rewilding for climate change.
Abstract
There is a cross-sectoral push among conservationists to simultaneously mitigate biodiversity loss and climate change, especially as the latter increasingly threatens the former. Growing evidence demonstrates that animals can have substantial impacts on carbon cycling. As such, there are increasing calls to use animal conservation and rewilding to dually overcome biodiversity loss and mitigate climate change. Specifically, trophic rewilding-which involves restoring intact animal communities, functional roles and trophic structure within food webs, and natural ecosystem processes-utilizes a rewilding framework to simultaneously support biodiversity conservation and carbon capture and storage. Trophic rewilding is a complex conservation approach to mitigating climate change, involving accurate estimations of baseline conditions and continuous monitoring of carbon cycling and species impacts within a system. It is also predicated on garnering social support for both the reintroduction and monitoring of a species, and obtaining the animals themselves. We are excited by the growing interest in this potential, but emphasize that a species' net impact on ecosystem carbon dynamics is context-dependent. Caution is required whenever biodiversity conservation (including rewilding), climate change mitigation, and human welfare do not readily align. Hence-similar to other nature-based solutions-these burgeoning efforts must avoid sweeping generalizations. To bolster successful trophic rewilding, we highlight a range of social and ecological context dependencies that can vary outcomes in a rewilded carbon cycle and provide ethical considerations for successful implementation. We conclude with an overview of the available technology to predict and monitor progress toward both biodiversity and climate mitigation goals.