Guillaume Latombe, Ugo Arbieu, Sven Bacher, Stefano Canessa, Franck Courchamp, Stefan Dullinger, Michael Glaser, Bernd Lenzner, Ivan Jarić, Anna Schertler, Franz Essl, John R.U. Wilson

Conservation decisions often need to integrate scientific predictions with societal values, ethical systems, and diverse perceptions that combine to form moral stances about conservation actions (e.g., trophy hunting or controlling invasive species). These can result in dilemmas and, if stakeholders hold different views on the morality of particular conservation actions, conflicts can arise. Here we adapt the well-known trolley problem thought experiment to a conservation context to offer a simplified, yet comprehensive framework enabling us to explore possible factors underlying differences in moral stances about such conflicts and better understand or predict them. Through the development of variations covering key concepts (asymmetry in numbers, victims and impacts; temporal and spatial asymmetry; uncertainty; causal relationships between actions and consequences), we provide a structured approach to elucidate moral conflicts in conservation. The trolley problem's versatility allows for the exploration of multiple scenarios deriving and combining these key concepts, facilitating a deeper understanding of the complexities inherent in conservation ethics. While acknowledging the need for contextualization and refinement, the conservation trolley problem also serves as a foundational step towards developing more nuanced thought experiments tailored to specific conservation contexts. The framework we present offers a systematic method to compare and analyse diverse ethical perspectives, fostering communication and facilitating informed decision-making in conservation practice. The integration of diverse metaphors offers avenues for enhancing dialogue between stakeholders, broadening perspectives, and advancing ethically sound conservation practices.