Yatsjuk Y. Functional role of generalist predators in oak forest ecosystems of the left-bank forest-steppe zone of Ukraine. Case study of Tawny Owl (Strix aluco L.)

The thesis for obtaining a PhD degree in biology on specialty 03.00.16 - Ecology. - The Institute of Agroecology and Environmental Management of National Academy of Agrarian Sciences of Ukraine, Kyiv, 2015. Main demographic parameters of a Tawny Owl population are presented on the basis of long-term monitoring study in elevated Oak forest of National Park "Gomilshanski lissy". Number of territorial pairs and its changes on the studied plot, main breeding performance and annual population growth indices are given. Trophic relations are established on the basis of analyses of pellets which have been collected over an 11-year period each season separately. Determination of natural shelters supply has been determined along with patterns of their use and determination of requirements for them. Recommendations on regional aspects of Tawny Owl population monitoring are given. It has been found that due to high productivity of tree species and high habitat diversity favorable conditions for high and stable number of small rodents are created. In turn, it creates advantageous conditions for the existence of sedentary rodent feeding species capable for switching between different types of small mammals, such as Tawny Owls. Diversity of tree stand types along with availability of different shelter types guarantees stable existence of a Tawny Owl population at relatively high numbers.