Results of counts of wintering birds of prey in 2011 in the Central Dnieper area

March 24th, 2011 Posted in Field researches, Photos, Wintering

In January-February 2011 we have carried out counts of birds of prey to monitor their numbers.

The counts covered districts of Cherkasy, Chyhyryn and Kaniv (Cherkasy region), as well as Svitlovodsk district (Kirovohrad region) and Kremenchuh district (Poltava region). Three counts were conducted in agrolandscapes using an automobile. Additive data were received during field visits and excursions in other areas and biotopes.

Results of winter counts of Falconiformes in agrolandscapes of Central Dnieper area in 2011.

Species Date / length of the route, km Total, ind.
9.01/50 24.01/57 22.02/61
Goshawk 1 1
Sparrowhawk 1 1 1 3
Rough-legged Buzzard 6 4 6 16
Common Buzzard 6 6 3 15
White-tailed Eagle 1 1
Kestrel 1 1
Number, ind./km 0,28 0,21 0,18 0,22

Generally, the number of birds of prey in the winter of 2010-2011 was extremely low. Compared with January 2009, when we conducted counts according to the same technique and approximately in the same sites, the number of Falconiformes during the current winter was 4 times lower. The total number was smaller mainly due to the Common Buzzards, which were 6 times less; the count numbers of the Rough-legged Buzzards were 3 times lower. Reduction of the Common Buzzard numbers we connect, primarily, with cold and snowy conditions of the previous winter, when there was mass mortality of these birds from starvation. We assume that a grouping of the wintering Common Buzzards, which had been formed during the last 5-6 years due to reduction of the distance of autumn movements, suffered from a significant “stroke” last winter. Although we agree with Sergey Domashevsky, that populations of raptors in Europe in the breeding season of 2010 were affected with heat and fires, which led to an extremely low breeding productivity, but there is no reason to think that it could brought about the 6 times reduction of the population of the Common Buzzard. Decline in bird numbers on wintering grounds in the Central Dnieper area is also linked with redistribution of birds within the wintering area. Also in the neighboring Kyiv region S. Domashevsky recorded low number of birds of prey during this winter. The number of hawks in our counts is not indicative, since these birds prefer not to stay in agricultural landscapes in winter.
Similar to previous years, the Common Buzzard and Rough-legged Buzzard dominated, their ratio was approximately equal. Except for main counts, the Hen Harrier was once observed. The Merlin was not recorded even once for the whole winter. Thus, we observed 7 species of Falconiformes.

Maxim Gavrilyuk, Alexandr Ilyukha, Nikolay Borisenko, Sergey Nadtochy

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