Comparison of population densities of selected bird species breeding in main urban habitats in southwestern Poland
A simplified version of the territory mapping method was used. Four counts were conducted in a fragment of the city of Wrocław in the spring and early summer 2010. Two main urban habitats were distinguished: a densely built-up area with block buildings and a residential area with flat houses. In total, 44 bird species were recorded as breeding in the whole study area. Five species nested in a density higher than 10 pairs per 100 ha each: Columba palumbus, Pica pica, Streptopelia decaocto, Sylvia atricapilla, and Turdus merula. Whereas in the densely built-up areas Columba palumbus and Streptopelia decaocto were equally common, in the residential area Streptopelia decaocto was almost three times more common than Columba palumbus. Pica pica was about three times more common than Corvus cornix both in the builtup areas and in the residential areas. Although densely built-up areas and residential areas have a similar species composition, many species breed in different densities. This is probably due to a different structure of vegetation. While tall trees are relatively common and shrubs rare in the densely built-up areas, the reverse situation prevails in residential areas.