Migratory concentrations of the White-tailed Eagle near Kremenchuhske Reservoir

December 12th, 2009 Posted in Field researches, Migrations, Photos, Video

In recent decades the number of White-tailed Eagle (Haliaeetus albicilla) has increased across the European range. To provide effective protection of the species there is a need to understand the biology and characteristics of distribution in all seasons. That is why in the process of study and monitoring of the White-tailed Eagle in the Middle Dnieper we paid attention to the sites of autumn concentrations of these birds.

White-tailed Eagles’ air playing (by the author)

This communication presents the results of research for the autumn 2009. To study distribution of the White-tailed Eagle we surveyed the sites, potentially attractive for feeding: shallows of Kremenchuhske Reservoir and surrounding fishponds. The total length of the automobile route was approx. 1000 km. The counts were also participated by N.Borisenko and A. Ilyuha.

photo: M. Gavrilyuk, S. Domashevsky

In autumn White-tailed Eagles distribute unevenly in the Middle Dnieper. Adult birds in most cases remain in areas of breeding sites; frequently young birds stay with them. However, majority of immature birds concentrate in the area where feed reserves are more abundant. These are such areas as fishponds as well as shallows of reservoirs, where waterfowl concentrate. The results of counts of 2009 surpassed the number of birds observed in previous years and all of our wildest expectations.

Aggregations of the White-tailed Eagles (by the author)

Have you ever seen more than 100 White-tailed Eagles at once? The author of these lines was lucky enough to watch the spectacle. I must say that at first it fascinated: eagles are everywhere – they sit on the ground, on trees, circling in the air. In this case there is a feeling of unreality, and then satiety. This is the same as for the first time at the zoo you see an ostrich, and then go to the ostrich farm … But the eagles are not ostriches and in Ukraine they aren’t bred. Where do so many of them appear? After all, at Kremenchuhske Reservoir there are only 15-20 breeding pairs. First, this is because of migratory movements – during autumn the number of eagles at the ponds increases. The vast majority (ca. 86%) are immature birds. It corresponds to the opinion that they are more inclined to migrate. Therefore, some eagles are “not Ukrainian” origin. Secondly, such a high number is a consequence of growth of the species population over the whole European part of the range. Ten years ago on the same ponds there could be found not more than two dozens of eagles.

In November 2009 near Kremenchuhske Reservoir there were approx. 300 White-tailed Eagles! (Table).

Site of observation (Map) First cycle of counts (late September-early October) Second cycle of counts (late October-November)
Ponds near the village of Irkliyiv (Chornobay district, Cherskasy region) 52 140-150
Ponds near the village of Bagayivka-Svyatylivka
(Globyno district, Poltava region)
26 105
Ponds near the village Chervona Sloboda-Sagunivka
(Cherkasy district)
6 4
Lypovskyi Ornithological Reserve (Zolotonosha district, Cherkasy region) 2 19
Total 86 268-278

The largest concentration was observed on the ponds near the village of Irkliyiv, where in late October the were up to 150 ind. Taking into account our estimate of the number of wintering White-tailed Eagles in Ukraine as 400-450 ind., it appears that in one place you can simultaneously see about a third of the birds that occur in Ukraine. Overall, at Kremenchuhske Reservoir there was concentrated more than a half of “Ukrainian” wintering population. The higher concentration of these eagles in Ukraine was observed only in the winter of 2006, when during severe frosts on Kinburn Peninsula approx. 300 eagles were seen (Petrovich, Redinov, 2007).

Immature White-tailed Eagles on feeding (by the author)

Thus, fishponds in the Middle Dnieper are among the areas that have the largest concentrations of the White-tailed Eagle in Ukraine. However, they have no protected status and stay of eagles there largely depends on the attitude of pond employees. Fortunately, at present it is friendly and we are trying every way to encourage it. To the benefit of eagles the ponds are protected, so people’s access to them is restricted.
In the future our efforts will be aimed at monitoring of concentrations of eagles and development of strategies for their protection in such places.

Maxim Gavrilyuk

Map: Points of counts of the White-tailed Eagles in autumn of 2009.