Fire-Induced Changes in Daily Butterfly Assemblages in Mediterranean Forests: Insights from the Edough Massif, Algeria

Forest fires significantly alter the biodiversity of Mediterranean ecosystems, particularly butterfly communities, which are sensitive bioindicators of environmental changes. This study compares the diversity and structure of diurnal butterflies in two cork oak forests of the Edough Massif (Algeria): a natural forest and a post-fire forest, based on surveys conducted from March to July 2023. Butterfly sampling was carried out using two complementary methods: a modified linear transect approach based on the British Butterfly Monitoring Scheme (BMS) and the Kilometric Abundance Index (KAI). Species abundances were recorded along predefined transects under standardized conditions. The results show a significant decline in species diversity after the fire, with only 11 species recorded in the burned habitat compared to 31 in the natural forest. Abundance analysis reveals that some sensitive species disappear or become rare, while others, more fire-resistant, benefit from the newly created ecological conditions. The Bray-Curtis index highlights a moderate but notable transformation of butterfly communities. These findings confirm that fire acts as an ecological filter, structuring populations according to their tolerance to disturbances. The study emphasizes the need for adapted management and restoration strategies to mitigate the effects of wildfires and promote the resilience of Mediterranean ecosystems.