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The urban environment has attracted much scientific attention as it stands at the core of environmental changes caused by the growing human population. The responses of bird communities to urbanization have been especially frequently studied. Despite the intensive research, there are several unresolved questions resonating in the field of urban ecology of birds: i) Are cities ordinary components of the original environment with the same macroecological bird diversity patterns as can be observed in the surrounding environment or do they have some specific impacts on native avifaunas? ii) Which traits are characteristic for species being able to persist in cities and for those avoiding urban areas? iii) How does the impact of the most important factors influencing urban bird communities - area, habitat heterogeneity and spatial position - change with spatial scale? Towards answering these questions, data on breeding bird communities were extracted from 41 European urban bird atlases, avifaunas of regions in which cities are embedded were retrieved from the EBCC Atlas of European Breeding Birds. Finer scale bird community data were obtained from the atlas of Prague and by point counts conducted in Prague. Data on bird traits were collated from published resources and additional environmental and...

Spruce bark beetle (Ips typographus L.) is the most common and abundant beetle from the Scolytidae family in European forests. It is the most important biotic factor causing disturbances and affecting forest ecosystems. Thus, it recently became a subject of discussions, how to manage the forests properly in order to find an adequate equilibrium among economical, turistic and natural values of the forest. Many studies have shown a positive effect of bark beetle outbreaks on biodiversity and natural forest regeneration. It is hard to tell if these outbreaks are regular or not because there are many factors which can elicit them. However, just these factors can help us predict the probability of unforseen population outbreak. One of these methods can be monitoring of surrounding areas because these areas tend to be synchronised. For this purpose, multiple mathematical models can be performed, such as the Mantel test, which determines the correlation between two matrices. Keywords: Spruce bark beetle, Ips typographus, population dynamics, spatial correlations, Mantel test

Vliv altitudy na životní strategie a fyziologické nastavení ptáků Řešitel práce: Marek Brindzák Vedoucí práce: doc. Mgr. Tomáš Albrecht, Ph.D. Abstract The pace-of-life syndrome theory proposed that species with similar life-histories share physiological traits that are more similar than species with different life-histories. Despite the fact that life-histories and physiology are well studied in birds it is still unknown how altitude changes these traits. However, shifts in life-histories across latitudinal gradients, with slow pace characterized by high investment to the future reproduction in tropics and fast pace of life characterized by high to the actual reproduction in temperate, is well know. From this knowledge we can assume how birds solve the trade-of between survival and reproduction based on the environmental conditions. This thesis summarizes effect of altitude on selected life-histories and physiology traits, the findings are compared with latitudinal changes. The first part of thesis is focused on describing latitudinal and altitudinal effect on selected avian life-histories traits. The second part deals with the altitudinal effect on the selected physiological traits in birds. Birds breeding at high altitude exhibit novel pace of life with life-histories similar to a slow pace but with...

In this paper I deal with island biogeography and its applicability to isolated mountaintops, as an ecological equivalent of true islands. I discuss both true and mountain islands regarding their origin and the influence of long-term climate evolution on Earth. I underline some features of mountain islands, resulting from their topography and the dissimilarities of both types of island barriers. I find that mountain and true island communities might or might not have a number of species in a state of equilibrium, caused by balance between species immigration on island and their extinction. If the number of species on island is not in equilibrium, species extinction is not balanced by species immigration. I consider patterns of island communities, mainly nestedness, which has been frequently studied on mountain, as well as true islands. I discuss distribution patterns concerning invertebrates. And finally, I concentrate on recent methods of moutain island research and discuss mountain island isolation issues in terms of global warming.

This diploma thesis examines factors that have affect on the forest bird communities in managed and unmanaged forests in the Slovakian mountains Vtáčnik. The research was conducted by a line method based on three different stages of forest succession in pure beech and mixed stands. The highest abundance and species richness was found in the old unmanaged stands. Abundance and the species richness in managed stands at the age of 60 and 90 years did not show any significant difference. In conclusion, this thesis noted that the main factors affecting bird communities were tree height variability, amount of understory and the presence of dead wood.

The most widespread way of extraction of forest is still clearlcuting. It is almost impossible to find commercial forest without forest clearings. Forest clearing can be perceived as a special element in a connected forest. I am trying to find out the influence of these forest distributions on the bird community. I was interested how important the forest clearings will be in the different type of forests. In seven localities were collected set of environmental variability's and bird data, which were counted by point count method. There were deciduous and mixed forests as well as the coniferous monocultures. The data collection was conducted in the breeding season 2011 and 2012. I expected, that the forest glades ensure the heterogeneity in forest space and will increase the number of bird's species. I expected this influence more important in the coniferous than in the deciduous and mixed forests. This assumption was partly confirmed. The glades in the coniferous forests have higher influence, but it depends on the forest area. In large coniferous monocultures is the importance of glades high. In the case of deciduous and mixed forests the size of forests did not have a value. The tree richness has the bigger importance. With this variable correlate Common Chiffchaff, Eurasian Wren, Yellowhammer,...

Microorganisms are ubiquitous and can be found on the body of birds, in avian nests or may be carried into the nest along with nest-lining material. Microorganisms may therefore colonize eggshells of eggs in a clutch and subsequently penetrate into the egg contents. This so called trans-shell infection has been observed to affect hatching success, cause embryo mortality or subsequently influence hatchlings phenotype. Nevertheless, the probability of eggshell bacterial load or trans-shell infection depends on many factors, including environmental conditions, nest type, incubation pattern, and nest-lining material. Furthermore, some modifications of avian reproductive strategies may lead to reduction of negative effect of trans-shell infections, and significantly improve reproductive success. These mechanisms include incubation, mechanical and chemical barriers of egg, eggshell pigments or using of feathers and specific plants as nest lining material. Based on these findings, it can be concluded that the different reproductive strategies in birds should be a result of strong selective pressure caused by microorganisms. Although many recent studies have supported this assumption, research on this issue still suffers from many methodological shortcomings that must be eliminated in future studies.