Forest fires in Southwest Bulgaria (2015–2024) in the context of national wildfire activity

Forest fires are an important driver of forest ecosystem dynamics in Bulgaria, and recent decades have been characterized by more frequent and sometimes extreme fire seasons. This study analyses wildfire activity in Southwest Bulgaria (Regional Forest Directorates Sofia, Blagoevgrad and Kyustendil) in the context of national patterns for the period 2015–2024, using official statistics from the Executive Forest Agency (EFA). Annual and cumulative indicators were calculated for the number of fires, burned forest and total affected area, seasonal distribution, vegetation types, ownership and reported causes and then related to average statistics for Bulgaria. During the period 2015–2024, a total of 4,835 forest fires burned 62,320.9 ha of forest area in Bulgaria. In Southwest Bulgaria alone, 1,294 fires burned area 9,045.3 ha. The region accounts for 26.8% of the number of fires but only 14.5% of burned forest area, and shows a substantially smaller average forest area affected per fire (7.0 ha vs. 12.9 ha at the national level). Summer is the dominant fire season in terms of number of fires and burned area, but Southwest Bulgaria shows a relatively higher contribution of spring and winter fires. The year 2018 stands out as a typical “autumn-dominated” season, with more than 60% of all fires in Bulgaria and almost two thirds of those in the Southwest occurring in autumn. Broadleaved forests are most affected, and human activities (negligence and arson-caused fires) are the leading reported causes of ignition. The results indicate that Southwest Bulgaria has a specific fire regime, characterized by more frequent but generally smaller fires, and underline the need for regionally adapted fire risk assessment and prevention measures.