Scientific publications

In the wide sense biodiversity considers to cover all displays of variability of life, and its ethological constituent is as important for sustaining of population stability as others. We investigated the behaviour of Phylloscopus warblers at northern peripheral parts of ranges (Karelia, Russia) in comparison with the conspecifics from central parts of ranges and found out that plasticity of territorial systems and variety of behavioural reactions along with other adaptations allow them obtain the populations even in not optimal conditions. This is relevant for both aspects: within and between species – variety of territorial patterns of conspecifics lets them inhabit quite different sites in the vast ranges, and behavioral variation among birds of different species of the same place promotes all of them settle it. So, comparing conspecifics from central parts of ranges, Willow Warblers Ph. trochilus and Chiffchaffs Ph. collybita in Karelia have a shorter prebreeding period, less aggressive ways of territorial borders establishing and lack of some stages of stereotype pair formation. Such reduction of territoriality is mainly caused by the deficit of time good for breeding and relatively low population densities in northern regions. Concerning interspecific variations, Willow Warblers and Chiffchaffs (common species for the region which they have been settled for evolutionary long time) form high stable territorial structures, while Wood Warblers Ph. sibilatrix and Greenish Warblers Ph. trochiloides (settled here comparatively later) have more labile territorial structures that let them more actively move during the breeding season in search of potential reproductive partners. Besides, behaviour of Phylloscopus warblers also varied depending on the level of social tension in populations, habitat structure and volume of sites suitable for nesting and foraging. The reported study was partially supported by RFBR, project NN. 06-05-64368, 12-04-31872 and 15-05-03493_a.