Spatial and Seasonal Dynamics of Butterfly Diversity and Community Structure in Djurdjura (…)

ABSTRACT

Habitat heterogeneity and seasonal variation are key drivers of insect diversity, influencing species composition, abundance, and community structure across landscapes. Understanding these patterns is particularly important in Mediterranean mountain ecosystems, where environmental gradients and habitat mosaics contribute to biodiversity patterns. This study investigates butterfly diversity and community structure across five distinct sites in Djurdjura National Park (Algeria), each representing a different habitat type: protected cedar forest, degraded cedar forest, riparian forest, meadow, and cliff. Sampling was conducted from April 2022 to March 2023 using standardised transects. A total of 5527 individuals belonging to 57 species were recorded. Results indicate that butterfly assemblages show substantial overlap among the studied sites, with no statistically detectable separation in community composition given the limited spatial power of the sampling design. However, variation in species richness and abundance was observed among individual sites; notably, the site characterised as degraded cedar forest showed the highest richness, and sites featuring open landscapes supported higher abundances. Seasonal patterns strongly shaped butterfly communities, with a pronounced peak in diversity and abundance during summer, driven by favourable climatic conditions and increased plant resource availability. In contrast, winter and early spring showed reduced activity and simplified communities. Overall, the results suggest that within the limits of the studied sites, seasonal dynamics exert a highly pronounced structuring force on butterfly communities, whereas potential habitat-level differences remained statistically undetectable. These findings highlight the importance of incorporating temporal dynamics when assessing biodiversity patterns in Mediterranean mountain ecosystems.