According to reports published on the website of the Ukrainian Center for the Study of Birds of Prey and prepared by M. Franchuk, I. Zubkovych, M. Khymyn, Yu. Korkh and T. Kryvulskyi, various aspects of the nesting biology and ecology of the Greater Spotted Eagle (Clanga clanga) have been studied for many years in the Rivne Nature Reserve. More information about this research can be found on the website. Thanks to over 10 years of continuous monitoring, the reserve has become a research ground and allowed for the resolution of many questions regarding the biology of the Greater Spotted Eagle and its habitat. The scientific information obtained is valuable for analyzing the condition of wetland ecosystems and for planned work on restoring the hydrological regime of the Somyne and Syra Pohonia massifs in the reserve, where this species occurs.
Currently, in addition to the Rivne Nature Reserve, the Greater Spotted Eagle inhabits other locations. The core Ukrainian population is concentrated in the far north, within the Pripyat Polesie region, and local settlements are also located in the Chernobyl Exclusion Zone and elsewhere. Large-scale research on the Greater Spotted Eagle in these areas, led by Serhiy Domashevsky, concluded in 2016 (Domashevsky, 2017). Subsequently, monitoring in these areas has been sporadic, with greater activity in some places (such as in the Rivne Nature Reserve), less so in others, and in some places not at all. Other areas of research on the species, such as telemetry, have also developed independently.
In recent years, interest in the Greater Spotted Eagle as an indicator of environmental health has increased significantly. It is a key species for numerous national and international projects, and interest in it as a model species for the wetlands and forests of Polesie is growing. The results of joint work conducted at several sites and within several projects implemented by the Nature Reserve Fund (PZF) allowed for the expansion of the geographic scope of research on this rare species. This collaboration was carried out with the participation of three PZF entities operating in the Pripyat Polesie region: the Rivne Nature Reserve, Nobelsky National Park, and the Pripyat-Stokhod National Park. Below is a brief summary of the results provided by the aforementioned authors.
The collaboration included both joint research activities on the species and the continuation of activities initiated in the past. Therefore, the work was divided into the following stages:
- Stage 1. Winter nest search in potential habitats. The primary focus was on searching for nests within the Pripyat River valley (Nobelsky National Park and the Pripyat-Stokhod National Park) and in the areas adjacent to the Rivne Nature Reserve. Three teams combed potential wetland areas of the forest, mapped nests, and documented them photographically. Unfortunately, due to the lack of stable frosts and unusually high water levels in January and February 2024, access to many areas was impossible; entry to border areas was also banned due to the war. Despite these circumstances, the teams managed to locate over 20 nests of diurnal birds of prey and black storks (Ciconia nigra).
- Stage 2. Search for potential breeding territories. Between May and July 2024, a number of field trips were conducted to record individual Greater Spotted Eagle territories. A total of 10 such locations were identified (7 within the Pripyat-Stokhod National Park and three within the buffer zone of the Rivne Nature Reserve).
- Stage 3. Verification of the breeding status of known nests and those found during the winter. A total of 31 nests were examined, 10 of which were previously known (Rivne Nature Reserve), 21 were found in winter (16 in Nobelsky National Park, two in Pripyat-Stochod National Park, and three in Rivne Nature Reserve and its buffer zone). Of these nests, 10 belong to the Greater Spotted Eagle (7 of which were occupied and had offspring, the rest are unoccupied and destroyed). It is worth noting that Greater Spotted Eagle nesting sites known from 2016 and 2018 were also examined. In some locations, the Greater Spotted Eagle remained and continued nesting (a chick was present), while in others, the Greater Spotted Eagle abandoned the nesting site due to its natural enemy, the white-tailed eagle (Haliaeetus albicilla), settling nearby.
- Stage 4. Tagging of chicks. Traditionally, this was carried out on known nests in the Rivne Nature Reserve, as well as on three newly occupied nests. A total of seven chicks from seven nests were tagged with colorful plastic and metal rings from the Ukrainian Bird Ringing Center. This is the highest number in 12 years of ringing this species in Ukraine.
- Stage 5. Monitoring nest ecology using camera traps. Since 2020, monitoring of Greater Spotted Eagle nesting has been carried out using camera traps, which involve installing them on nests in March (before the arrival of adult birds from their wintering grounds). Then, in July, during nest occupancy checks, memory cards and batteries are replaced, and in October, they are removed. In 2024, camera traps were successfully installed on six Greater Spotted Eagle nests. All camera traps functioned correctly.
As a result, the joint study of the Greater Spotted Eagle identified new nests and also demonstrated the need for further research to identify and verify the species while nesting in the Pripyat wetlands. This provides the basis for other studies (genetic, telemetry, and camera traps) planned within several subsequent projects.
The research was supported by the following projects:
- „Promoting the conservation of the Greater Spotted Eagle breeding population in Ukraine in 2024” with the support of the German Association for Nature Conservation and Biodiversity (NABU), implemented in Ukraine by the Ukrainian Society for the Protection of Birds;
- „Polesie – Wildlife Without Borders” with the support of the Frankfurt Zoological Society.
References
Domashevsky S.V. Current population status of the golden eagle (Aquila clanga) in Ukraine. Berkut 2017. 26 (1). 49-59.