Gregarious behaviour and feeding sites of Paridae and Aegithalidae wintering in Oltrepò Pavese plan

Abstract

I have collected data on foraging niches of Great Tit Parus major, Blue Tit Cyanistes caeruleus and Long-tailed Tit Aegithalos caudatus in a deciduous woodland area in Oltrepò Pavese (Lombardy, N Italy) in winter 2006-2007. All species showed a high propensity to flock. The mean flock size was 6.1 birds. Unlike Long-tailed Tit, Great Tit and Blue Tit were more abundant in monospecific flocks than in heterospecific ones. The groups containing Blue Tits were less compact than others. The space distribution of the three species during feeding differs significantly. In monospecific groups Great Tit showed a strong tendency to forage mainly on the ground. Blue Tit and Long-tailed Tit have always privileged the trees as feeding substrate.