Accounting for spatial heterogeneity in trapping pressure and its impact on population dynamics of sympatric pine and stone martens

The consequences of human exploitation of animal populations remain poorly understood, particularly for populations experiencing spatially-varying harvesting intensity and exposure. If unaccounted for, this heterogeneity may lead to inappropriate harvesting policies. We developed a spatially-explicit individual-based model to evaluate the effects of such spatially heterogeneous harvesting on the population dynamics of pine and stone martens in France. By comparing scenarios of spatially heterogeneous and homogeneous trapping pressure, we investigated the sustainability of current voluntary trapping practices in the absence of dedicated population monitoring. We show that spatially heterogeneous trapping pressure, despite being lower pressure on average than our simulated homogenous trapping, has a stronger, more negative impact on population size and density of both species. Our results highlight the need to account for the spatial heterogeneity when assessing the effectiveness of management practices. Neglecting spatial heterogeneity when assessing or formatting harvesting practices may unintentionally generate management strategies that yield unforeseen consequences for the target populations.