The tick species Hyalomma marginatum is the primary vector for transmitting the virus responsible for Crimean- Congo Hemorrhagic Fever (CCHF) in Europe. Recently introduced in southern continental France, likely through migratory birds and domestic and wild animal movements, and particularly adapted to the Mediterranean climate, H. marginatum is expected to spread to previously uncolonized zones due to a combination of interacting ecological, climatic, land-use and human behavioural factors. To date, no human cases of CCHF have been declared in France; however, recent studies have confirmed virus circulation amongst wildlife, domestic livestock and H. marginatum ticks in the Pyrenées-Orientales, a southern French department, raising concerns about potential public health risk. In this context, it is increasingly important to understand the social-ecological system (SES) of CCHF risk in order to anticipate emergence at the local level and inform institutional response. This study aimed to characterize the SES of ‘tick risk’ in the Pyrenées-Orientales by integrating scientific and local actor expertise through participatory methods to co-define territorially relevant and actionable research themes. Three participatory workshops were conducted in Prades (Pyrenées-Orientales) between April and May 2025 with local actors including nature users, livestock farmers, game hunters, biodiversity protection agents and nature educators. Workshops were sequentially structured to: (1) co-identify the ‘tick risk’ research problem, (2) map actor-actant interactions within the system, (3) co-define system boundaries and spatialize perceived tick risk across the territory, and (4) co-define research themes and study proposals. Qualitative and participatory analysis methods were employed throughout to synthesize outputs and ensure iterative validation with participants. Participants collectively formulated the research problem as: «Better understand tick risk in the Conflent-Canigou to prevent tick infestation on animals and humans.» They subsequently produced an actor-actant interaction diagram identifying human (actor) and non-human (actant) elements of the SES and their interactions, and collectively spatialized ‘tick risk’ by producing a participatory map of perceived high and low risk areas in the Conflent-Canigou zone. The process resulted in three co-defined transdisciplinary research themes, accompanied by in-situ experimentation proposals that bring together researchers and non-academic actors: (1) a multi-actor evaluation of tick risk exposure for nature users, (2) a participatory modeling study of livestock farming practices and the impacts of Hyalomma spp. infestation on livestock, and (3) a futures study anticipating the impacts of evolving tick risk in the region under ecological and socio-economic change scenarios. A transdisciplinary approach proves essential for actionable, territorially grounded, tick risk research.