POST-FLEDGING BEHAVIOUR OF A JUVENILE EASTERN IMPERIAL EAGLE (AQUILA HELIACA) TRACKED BY GPS IN THE TAUKUM DESERT, SOUTHERN BALKHASH REGION IN KAZAKHSTAN
DOI:
https://doi.org/10.26577/bb202510328Ключевые слова:
филин, поведение птиц, ночные птицы, GPS телеметрия, GSM передатчик, использование среды обитания, охрана птицАннотация
The post-fledging period is a critical stage in raptor development, influencing survival, dispersal, and recruitment into the breeding population. However, knowledge of juvenile Eastern Imperial Eagle (Aquila heliaca) movement ecology remains limited, particularly in Central Asia. This study presents the first GPS tracking-based analysis of a juvenile Eastern Imperial Eagle from the Taukum Desert, Balkhash-Alakol Basin, Kazakhstan, providing insights into post-fledging dispersal, movement behavior, and habitat selection. The study aimed to document the timing of dispersal, territorial expansion of the range and habitat use of post-fledging Eastern Imperial Eagles during the first months (Aquila heliaca).A 65-day-old nestling was fitted with a GPS- transmitter and monitored from mid-July to late September 2024. Movement patterns were analyzed using GPS telemetry and Kernel Density Estimation (KDE) to assess habitat preferences.
The eagle was tracked for 77 days, producing 1,859 GPS locations and covering 713 km. It remained within 2 km of the nest for six weeks before gradually expanding its range. True dispersal began at 112 days old, marked by a 6-8 km westward flight. The maximum recorded distance was 18.6 km (September 11, 2024), while the longest single-day movement reached 49.6 km. Flight altitude averaged 453.5 m, peaking at 1,498 m, with a maximum flight speed of 85.9 km/h. Habitat analysis showed a strong preference for semi-desert steppe and riparian habitats, with over 95% of locations in natural landscapes. The eagle avoided human settlements. KDE identified core home ranges within 10 km of the nest, extending up to 290 km².
The study highlights the importance of preserving natal habitats and implementing powerline hazard mitigation measures to prevent mortality of young raptors. Future studies should track multiple individuals to assess dispersal and survival trends in Central Asia. Future research should track multiple individuals to assess dispersal trends and survival in Central Asia.
