Results of spring counts in the alienated zone of Chornobyl Atomic Power Station (CAPS) in March 2011
The Chornobyl alienated zone always attracts researches with its wild surroundings almost deprived of traces of human activity, and with abundance of various groups of animals and birds. We used a chance to realize our old desire for searching Strigiformes birds in this region, and carried out counts 21 to 25.03.2011.
For this purpose we applied a well-known method of provoking owls by records of their voices. In forest sites we played voices of the Pygmy and Tengmalm’s Owls, Great Grey Owl, in open areas – those of the Eagle Owl. Records of the Tawny Owl we used only occasionally since the species is numerous in forest areas and frequently responses voices of the above-mentioned owl species.
Information on availability of owls in the alienated zone is very poor. Data on the Great Grey Owl is limited by 6 encounters, mainly in the western part of the zone (Gashchak et al. 2006; Domashevsky 2004; pers. comm. A.V. Yastremsky). A Pygmy Owl was observed in twilight at Belorus border by S.P. Gashchak 30.06.2009 (pers. comm.) In addition, there were several records of the Eagle Owl including a fledgling found nearby the atomic station (Gashchak et al. 2006).
We started owl counts when twilight came. Moving by automobile in the forest area we made stops each 600-1000 m and played bird voices. At first we used records of small owls and finished with large ones. In opener territories (river valleys, overgrowing fields) we provoked with voices of the Eagle Owl each 2 km. This way we actively worked until midnight, then took a little rest and renewed counts from 4.00 a.m. to the sunrise. During the daytime we studied bird migration. Night counts covered the distance of approximately 137 km. The overall automobile route travelled in the alienated zone equaled to 860 km.
In the process of counts only 2 owl species were revealed: Tawny and Long-eared Owls. Besides, some small owl flickered in the car headlights in Krasno Village. Once, an owl (Tawny or Long-eared) without giving the voice approached very closely in Kopachi Village. No doubt, these results are more than scanty; they do not reflect real numbers and species composition of owls in this territory. Weather conditions also impaired the result since the last night in a promising region of counts was windy and rainy.
Diurnal migrations were not very active because of wind and some precipitation (rain, and 25.03 snow that turned into rain). Among Falconiformes there were registered: Common Buzzard – 22, Hen Harrier – 5, Sparrowhawk – 3, Goshawk – 2. Local Common Buzzards stayed near their breeding areas. Only 1 Kestrel from the breeding population was registered, all the rest did not arrived yet from their wintering grounds. The White-tailed Eagle was observed 14 times, of them 12 birds in adult plumage. Two Ravens were captured and ringed in the Uzh river valley. Everywhere in morning hours it was heard displaying of Black Grouses which are in a great number there. At night we were entertained by howling of wolves, which are also numerous in the zone, one beast even walked in front of the car at the 20 m distance. Hoofed animals also were frequently seen.
Results of these counts do not mean that such species as the Eagle Owl, Great Grey Owl, Tengmalm’s and Pygmy Owls are absent in the Chornobyl alienated zone. There is a need in further expansion of searching territory and repeated investigations in promising areas.
We are sincerely grateful to the company management of “Baker Tilly Ukraine” for the sponsorship of these field studies.
Sergey Domashevsky, Ukrainian Birds of Prey Research Centre
Igor Chizhevsky, Chornobyl Radioecological Centre”
Sergey Gashchak, State Scientific Research Organization “Chornobyl Centre on Issues of Nuclear Safety, Radioactive Waste and its Radioecology”
References
Gashchak S.P., Vishnevsky O.O., Zalisky O.O.: Fauna of vertabrates of the Chornobyl alienated zone (Ukraine). – Publishing house of the Chornobyl Cetre on Issues of Nuclear Safety, Radioactive Waste and its Radioecology”, 100 p. [in Ukrainian]
Domashevsky S.V. 2004.: Great Grey Owl (Strix nebulosa) in Kyiv Polissia. – Vestnik Zoologii 38 (2): 20. [in Russian]