Paweł Mirski, Sylwester Aftyka, Stanisław Broński, Dawid Cząstkiewicz, Mateusz Gutowski, Sławomir Rubacha, Arkadiusz Sikora
Ornis Polonica 2026, 67: 67-93
https://doi.org/10.12657/ornis.2026.2.1
Abstract: The Eurasian Eagle-Owl Bubo bubo is an extremely scarce breeding species with a high conservation status in Poland. At the beginning of the 21st century, its population was estimated at 270–380 pairs and population trend was interpreted as increasing. However, population declines in Scandinavian and Baltic countries, along with a marked decline observed in recent years in certain national populations in the lowlands, suggest a worsening situation for the species. Therefore, the aim of this study was to update the knowledge on Eurasian Eagle-Owl abundance in Poland and the directions of change in regional populations. We summarized data on the number of territories between 2012–2018 and 2021–2025 (and 2017–2025 for Silesia). A national population decline averaging 31% was recorded, down to 170–240 territories, with a sharp decline in the lowlands, a smaller decline in the Małopolska and Podkarpacie regions, and a stable situation in Silesia. High rates of predation on broods, anthropogenic mortality, and the disturbance of breeding by human activity near nests as well as a potential deterioration of the prey base in lowland wetlands were identified as the primary causes of the population decline. Given the difficulty in detecting this species, guidelines for monitoring Eurasian Eagle-Owl populations are also discussed.
Keywords: conservation, monitoring, owls, population decline
