Interview Maxim Gavrilyuk about the White-tailed Eagle in UkraineDate of the interview: 26 December 2009 In this interview Maxim Gavrilyuk talks about the current situation and the biology of the White-tailed Eagle in Ukraine. Click here for a Russian translation
Maxim Gavrilyuk: By 2009 we have known about 100 breeding sites of the White-tailed Eagle in Ukraine, so the number is estimated at 100-120 pairs (Gavrilyuk 2009). The breeding productivity is rather high - the average number of fledglings per a successful pair is 1.49 (Gavrilyuk, Gryshchenko 2008). Markus Jais: How has the population developed during the last 20 years?
Maxim Gavrilyuk: The minimum number (20-30 pairs of White-tailed Eagles) bred in Ukraine in 1960-1970s. The recovery of the population along the Dnieper began in the second half of 1970s, in other regions – from the mid 1980s. In 1989 the breeding population was 30-40 pairs. Over the last two decades the number of the White-tailed Eagles has been growing. In the mid 1990s 50-70 pairs bred (Gavrilyuk 2004). Markus Jais: Where do White-tailed Eagles breed in Ukraine?
Maxim Gavrilyuk: Currently, the species breeds along the Dnieper and in the lower reaches of its main tributaries, at the Seversky Donets River, the Danube River, as well as near some large fishponds in other regions. The Dnieper valley holds about 70% of the breeding pairs. Markus Jais: In some European countries, at least some White-tailed Eagles seem to get more used to people. There are more and more nests in open agricultural areas or close to busy streets, villages or cities. Do you notice a similar trend in the Ukraine?
Maxim Gavrilyuk: In general, the White-tailed Eagles in Ukraine have become more used to people, compared to the period of 30-40 years ago. But today any cases of breeding in the conditions, which you mentioned, are not known. The White-tailed Eagles prefer to nest in traditional sites. But there is a tendency to nest on younger trees (e.g. comparatively young pine-trees), in forests of small size. These adaptations already enable the eagles to broaden their habitats. However, this process has a downside. When nesting in more open areas the eagles put themselves at risk of direct disturbance, which results, as a rule, in unsuccessful breeding. Therefore, fixation of such a nesting type will depend on the attitude of the local people toward the eagles.
White-tailed Eagle. The king of the sky.
© Sergey Gladkevich
Maxim Gavrilyuk: Over the last decades, the breeding density of the White-tailed Eagles has increased. But until now it hasen’t yet reached the maximum in optimal habitats. An evidence is the distance between nests (usually it is 5-10 km), and the fact that the eagles just began to occupy suboptimal biotopes. These facts allow us to expect that the number of eagles will grow. Markus Jais: What tree species are used mostly for the nests?
Maxim Gavrilyuk: About half of the White-tailed Eagle’s nests are located on pine-trees, 16% - on poplars, 12% - on alders, all the rest - on other kinds of trees. The usage of different trees depends on the area of breeding - in the river floodplain they are mainly poplars and willows (Gavrilyuk 2002). Markus Jais: Is there a difference in the breeding success between the different tree species used for nests?
Maxim Gavrilyuk: No, we did not notice any differences in the breeding success relating to the tree species used for nesting. This indicator is the most dependent on the extent of human disturbance within the breeding area. The nests built on poplars are more often destroyed by strong winds, compared to those on pine-trees. On the other hand the nests located on the pine-trees have more chances to suffer from tree felling.
Juvenile White-tailed Eagle in nest.
Have you brought me the fish or only the ring?
© Maxim Gavrilyuk
Maxim Gavrilyuk: The feeding base almost everywhere is fish - it amounts to 80% of the diet. The White-tailed Eagles catch it from rivers as well as fishponds. The captured fish is dominated by the bream, pike-perch and carp. The percentage of birds as prey objects increases during winter, especially in the areas which support high numbers of wintering waterfowl, e.g. in the south of Ukraine (Gavrilyuk 2002). Markus Jais: How many White-tailed Eagles do spend the winter in Ukraine?
Maxim Gavrilyuk: According to our estimates, in Ukraine there are about 400-450 wintering White-tailed Eagles. Their number, as well as the number of breeding eagles, has increased during the last two decades. Depending on the winter conditions, the number can vary greatly in different regions of Ukraine. For instance, in recent, rather mild winters, many White-tailed Eagles in December - January were concentrated at fishponds of the Middle Dnieper. In case of more severe conditions the eagles migrate further south - to limans and the Azov-Black Sea coast. For example, during severe frosts in early February 2006, on Kinburn Peninsula up to 300 eagles were observed there (Petrovich, Redinov 2007). Certainly, the majority of wintering birds are from Ukraine. However, there are records of eagles ringed in Poland, Lithuania, Estonia, Belarus and Finland. Therefore, in our opinion, it is essential to implement projects to study the eagle’s migrations with use of satellite telemetry from the territory of Ukraine, as well as from more northern regions such as Russia and Belarus. Markus Jais: What are the main threats to White-tailed Eagles in Ukraine?
Maxim Gavrilyuk: The main threats to the White-tailed Eagle population in Ukraine are forestry activities, high recreational load in their breeding sites along the river banks, illegal shooting, depletion of food resources and environmental pollution. Markus Jais: How many birds die from lead poisoning? Are there efforts to make lead ammunition illegal or are hunters encouraged to use non lead ammunition?
Maxim Gavrilyuk: We know several cases of the eagles death, presumably from poisoning. However, no special studies on lead poisoning of birds in Ukraine were conducted. Unfortunately, today the problem to ban the use of lead shot by hunters is just starting to raise in Ukraine.
The main food of the White-tailed Eagle is fish in Ukraine.
© Maxim Gavrilyuk
Maxim Gavrilyuk: No, at present we don’t know about such cases. Markus Jais: How much of the habitat currently used by the breeding pairs is protected? Are the areas around the nests protected from forestry work during the breeding season?
Maxim Gavrilyuk: Only 15% of nests of the White-tailed Eagles are located within protected areas of different status. This is the main problem for the conservation of eagles in Ukraine. According to the existing legislation of Ukraine only an occupied nest of the eagle is protected, there is no protective zone around it. Markus Jais: What needs to be done so that the population can continue to increase?
Maxim Gavrilyuk: It is necessary to eliminate the threats mentioned above. Above all, it is promotion of the protection of these raptors among local people and improvement of conservation measures.
Nests of the White-tailed Eagle don’t have protective (buffer) zones in Ukraine.
At the photo: The nesting pine died after the felling near the eyrie. The eagles left the eyrie next year.
© Maxim Gavrilyuk
Maxim Gavrilyuk: In a breeding period, it is easy to watch the White-tailed Eagles hunting in any part of the Dnieper River. As for the wintering period, the eagles are most easily seen near the areas where the water is not covered with ice: near dams of the hydroelectric power station on the Dnieper, at limans and the sea coast. During migratory movements concentrations of the eagles can be observed at fishponds. Markus Jais: What was your most amazing experience with White-tailed Eagles?
Maxim Gavrilyuk: Perhaps I feel the most excited when climbing up to the eagle’s nest at the height of more than 20 m to ring chicks. It is always amazing when there is a chance to see this beautiful bird at such a close distance. Sometimes funny incidents also happen. One day, climbing up the tree, I stopped to take a short rest on a branch just beneath the nest. At this very moment I heard flapping wings and a scuffling noise in the nest - an adult bird flew in with some prey, not noticing me from above. I sat quietly for several minutes until the adult eagle flew away. Markus Jais: Maxim, thank you very much for the interview.
Further InformationUkrainian Birds of Prey Research Centre
ReferencesGavrilyuk M. N. (2002): Orlan-bilochvist v Ukrjini: suchasny stan, biologija ta ochorona [The White-tailed Eagle in Ukraine: current status, biology and protection. In: Manuscript. Thesis for a candidate degree of biological science. Specialty 03.00.08 – zoology. Schmalhausen Institute of Zoology, National Academy of Science, Ukraine]. − Kyiv. - 20 p. Gavrilyuk M. N. (2004): Izmeneniie chislennosti orlana-belochvosta na territorii Ukrainy v XX st. i vozmozhnyje ich prichiny [Population trends of the White-tailed Eagle in Ukraine during XX century and probable their reasons] // Berkut.. – Vol. 13, Is. 2. – P. 205–225. [in Russian with English summary]
http://aetos.narod.ru/online/berkut13-2/ecology13-2-4.pdf Gavrilyuk M. N. (2009): Orlan-bilochvist [White-tailed Eagle] // Chervona knyga Ukrainy. Tvarynnyj svit [The Red Book of Ukraine. Animals]. − Kyiv. − P. 432. [in Ukrainian] Gavrilyuk M.N., Gryshchenko V.N. (2008): Produktyvnist’ rozmnozhennja orlana-belochvosta v Ukraine v 1988−2008 [Productivity of the White-tailed Eagle breeding in Ukraine during 1988-2008] // Novitni doslidzhennja sokolopodibnych ta sov. Mater. 3 Mizhnar. konf. “Chyzhy patchy Ukrainy”, Kryvyi Rih, 24-25 October 2008 [In: Latest studies on Birds of Prey and Owls. Proceedings of the 3d International Scientific Conference “Birds of Prey of Ukraine”, Kryvyi Rih, 24-25 October 2008. (eds. M.N.Gavrilyuk, G.V. Fesenko)]. − Kryvyi Rih. − P. 79−85. [in Ukrainian] Petrovich Z.O., Redinov K.O. (2007): Znachennja Kinburns’koji kosy v zberezhenni orlana-bilochvosta v zymovyj period [Importance of the Kinburn for conservation of the White-tailed Eagle in winter period] // "Branta", the transactions of the Azov-Black Sea Ornithological Station. − Is. 10. – P. 156–164. [in Ukrainian with English summary]