Multi-scale landscape composition and local factors jointly shape the occurrence patterns of declining peatland dragonflies

Abstract Context Understanding how biodiversity patterns emerge from the interplay between landscape and local factors (e.g. habitat availability and local anthropogenic impacts) across spatial scales is fundamental for designing effective conservation strategies. Anthropogenic activities are having dramatic effects on freshwater invertebrate communities; however, the role of landscape structure in shaping their occurrence remains poorly understood. Objectives Understanding how (and at which spatial scale) landscape structure interacts with local factors in explaining the occurrence of threatened peatland odonates. Methods We investigated the unique and joint contributions of landscape structure, geoclimatic characteristics, habitat features, and anthropogenic impacts associated with the occurrence patterns of seven peatland dragonfly species in the Italian Alps. We applied a multi-scale analysis to identify the most strongly associated scale for each landscape variable, considering 50 incremental scales (100–5000 m). Results Local habitat features such as peatland typology explained a large and unique proportion of the total variance of occurrence for most species. However, most of them were also associated with landscape composition at spatial scales up to 5 km from reproductive sites. Occurrence patterns of Aeshna juncea and Sympetrum danae are partly explained by landscape features alone, whereas, for most other species, landscape features concurred to explain them. Conclusions We confirmed that dragonflies are sensitive to landscape structure at broader species-specific scales than previously recognised. Our results support previous local-scale conservation recommendations for peatland dragonflies, also highlighting the need for landscape-scale conservation approaches, i.e. preserving Alpine peatland networks, maturation habitats (e.g., woodland around mires), and mitigating urbanisation impacts.