The hypothesis tested concerned whether the diet of the tawny owl Strix aluco, as an opportunistic predator, does reflect increases in the density of bat populations in the owl’s hunting areas. In our study area, there was a mass use of toxic pesticides during which numbers of bats declined drastically, after which recoveries in the populations of most European species occurred. Thus, in Poland, numbers of bats reached their lowest levels in the 1980s. We examined the diets of tawny owls in Warsaw and the adjacent Kampinos Forest of central Poland, based on the remains of 9142 prey items. Bat specimens were found to comprise the following percentages of all vertebrate prey items: 1976–1989: 0.03–0.14%, 1990–1999: 0.32–0.40%, and 2000–2007: 0.54–1.71%. If the share taken by bats among mammalian prey is in turn considered, the analogous figures are 0.09–0.17%, 0.45–0.99% and 0.92–3.26%. Patterns in owl diets were consistent with trends in bat numbers at 15 large winter roosts located some 10–50 km from the study area in 1989–2006.
The study aims at presenting the development of research on the upper level of bourgeois society in Czech historiography. It focuses on the comparison of crucial terms used in these discussions, such as patriciate, notables and elites., Josef Kadeřábek., and Obsahuje seznam literatury
The article deals with the topic of migration from cities to villages in the Czech Republic and Austria and the opportunities for the social integration of newcomers. It relates partly to the problems of suburbanisation but is not limited to just migration to suburban villages. The analysis is based on a qualitative study conducted in 2003-2004 using grounded theory, and it examines the subjective viewpoints of the incomers and their assessments of their situation. The author reveals two different patterns of motivation for migration, presents a typology of relationships between the incomers and the village community, and distinguishes three basic 'orientations' among the incomers: a village orientation, a city orientation, and an orientation towards self-sufficiency. These specific orientations emerge in the process of mutual interaction between the preferences of the incomers and the integration opportunities offered by particular villages; they are not exclusive and can change over time. The author closes with a summary of the differences between the situation in the Czech Republic and Austria, which may be a result of different structural conditions and different historical backgrounds.
Ant assemblages were studied in Warsaw in the context of the effects of urban pressure. Four types of urban greenery were selected: (1) green areas bordering streets, (2) in housing estates, and (3) in parks, and (4) patches of urban woodland. In total, there were 27 species of ants. In terms of the total ant activity density, Lasius niger predominated in all the the lawn biotopes (1–3) and Myrmica rubra in the wooded areas. Ant species diversity was highest in parks and wooded areas and lowest in green areas bordering streets. In contrast, activity density was highest in green areas bordering streets and lowest in wooded areas. Some species are found only in a few habitats. Stenamma debile, Lasius brunneus, L. fuliginosus and Temnothorax crassispinus almost exclusively occurred in wooded areas, whereas L. niger was most often found in lawn biotopes. Myrmica rugulosa and Tetramorium caespitum were most abundant in green areas bordering streets, while in parks Lasius flavus, Formica cunicularia and Solenopsis fugax were most abundant. In general, the ant assemblages recorded showed a significantly nested pattern, with biotope type being a significant determinant of nestedness. The assemblages found in green areas in housing estates and bordering streets constituted a subsample of the assemblages in parks and wooded areas. Ant species were non-randomly distributed in this urbanized landscape and the species recorded in the most transformed biotopes constitute subsamples of those inhabiting less transformed biotopes. This finding emphasizes the importance of wooded areas for the maintenance of biodiversity in urban areas., Piotr Slipinski, Michal Zmihorski, Vojciech Czechowski., and Obsahuje seznam literatury