The birds of Pasvik / E. I. Khlebosolov, O. A. Makarova, O. A. Khlebosolova [et al. ; English transl. Nikita Chernetsov]. - Ryazan : Golosgubernii, 2007. - 175 с. : ил., портр.

ines different parts of the tree. It moves helically around the trunk and branches (Fig. 3.19, 3.20). The Great Tit is a relative newcomer in the forests o f the Kola Peninsula. Currently this species continues to expand its range, colonise new habitats and increase its numbers (Semenov-Tian-Shansky & Gilyazov 1991). In Pasvik this tit inhabits different types o f forest with prevailing deciduous trees. It mainly occurs along the roads, on the shores o f streams, lakes, rivers, and swamps. Most often Great Tits settle near human settlements, mainly in birch stands. Here this species reaches the highest breeding density, 2.9 pairs • km 2. Great Tits prefer to forage in the crowns o f deciduous trees with numerous first- and second-order boughs. They mainly feed in the middle and lower part o f the crown. Great Tits often forage in the underbrush or on the ground. When searching for food, they move in the inner parts of the crown on thick and middle- sized branches by flights and long hops. The bird often stops, looks for prey, then picks it from the substrate or extracts it from the bark cracks, stranded leaves and other covers (Fig. 3.19, 3.20). Titmice, like many other forest-dwelling passerines, feed in the crowns o f trees and bushes. Flowever, they avoid competition and can co-exist with other birds, because they use a specific strategy o f food search and foraging. Unlike birds that collect food from foliage and trunks or feed by flycatching, they prefer to extract prey from various covers: trunk and branch cracks, twisted leaves, butterfly cocoons etc. (Marochkina & Cheltsov 2005). In winter, this is the main foraging technique o f titmice (Preobrazhenskaya 1998, Khlebosolov et al. 2006b). Differences in the structure of their ecological niches that allow the three species to co-exist in the same area are due to species-specific foraging technique. The species considerably differ in their foraging behaviour, select typical microhabitats and habitats. The Siberian Tit is the most typical inhabitant o f boreal forests. They mainly breed in watershed habitats and feed in the trees with a narrow and elongated crown that grow in adverse environments on poor or too wet soils. Willow Tits penetrate to the north along the valleys o f rivers, streams, and lakes. In the valleys trees and bushes grow under better conditions than on watersheds, and form well-developed spheri­ cal crowns that are suitable for Willow Tits. Great Tits in Pasvik use anthropogenic habitats and mainly occur in the vicinity o f human settlements. However, recently this species has started to expand into natural habitats along the roads, banks of streams, lakes, rivers, and swamps. 140