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Selected impacts of climate change on birds in European mountains: shifts in altitudinal distribution, population changes and changes in phenology
Mikulcová, Eliška ; Reif, Jiří (advisor) ; Hološková, Adriana (referee)
Many studies focused on the impact of the climate change on organisms including mountain birds. Mountain birds are particularly threatened by the impact of climatic change because they occur in an extreme environment. Climate change impacts mountain birds through increasing temperature, which affects their altitudinal shifts and abundances. These two variables depend also on species-specific traits, distribution area and habitat change. This thesis aims to sort knowledge about impacts of climate change on mountain birds and to explain the variability of altitudinal shifts of these species. Species occupying lower altitudes, open habitat species and short-lived species showed the biggest upward shifts. Downward shifts occurred when the impact of habitat change outweighed the impact of climate change. No significant shifts were recorded in species that respond to climate change by changes in phenology which likely compensate the adverse climate change impacts without the need of translocation. Population trends were usually negative with the steepest declines in high- alpine species, ecological specialists, long-distance migrants and short-lived species. In order to reduce decline in numbers, it is important to set up effective local vegetation management and globally stick to climate targets. Key...
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Abundance and habitat use of reintroduced populations of the Hermit (Chazara briseis) in the Czech Republic
Pešová, Lucie ; Sedláček, Ondřej (advisor) ; Vrba, Pavel (referee)
The Hermit (Chazara briseis) belongs to the critically endangered species in the Czech Republic. Its last population survived until recently in the NPR Raná in the České středohoří Protected Landscape Area, but it has gradually declined. The specie's habitat is short-stemmed grasslands, which are maintained mainly by extensive grazing and management. Currently, these sites are declining, traditional management has changed and the sites are gradually becoming overgrown. Therefore, the reconstruction of the butterfly's habitats has been undertaken in selected localities that the butterfly used to inhabit in the past, in the České středohoří Protected Landscape Area (PR Číčov, Dlouhá hora, PP Radobýl) and in the Český kras Protected Landscape Area (Třesina, Radotín). Reintroduction of eggs and caterpillars took place in these sites in 2020-2021. The aim of the thesis was to evaluate the population abundance and habitat use of the Chazara briseis at these sites immediately after reintroduction. I estimated the size of the populations using the mark-capture-recapture method in 2020 and 2021. The size of the populations in the Lonské středohoří (Dlouhá hora and Číčov) was around 400-500 individuals with a fairly balanced sex ratio. Overflights were also recorded between these sites, which may indicate...
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Pesticide impacts on farmland bird populations
Kutzendőrferová, Adéla ; Reif, Jiří (advisor) ; Grünwald, Jan (referee)
Pesticides are problematic chemicals that are found in a variety of environments. These substances tend to accumulate in living organisms, where they decomposite very slowly and can have a negative impact on bird populations. This is why some chemicals are still detected in these environments today, even years after their use has been banned, and may continue to affect organisms. The aim of my bachelor thesis was to conduct a literature search on the impact of pesticides on farmland bird populations. The first part of the thesis focuses on pesticides, their history, their division into different systems and their effects. The second part of the thesis then discusses the overall effects of pesticide use on farmland bird populations, particularly on breeding success and abundance. In this part, several studies have been collected that confirm the negative effect of pesticides on bird abundance, but not all of these studies are representative of real situations in the landscape. Finally, the paper assesses the overall role of pesticides in the observed bird declines and also presents suggestions to address the current negative trends. The thesis points to the need for expanded research studies that reflect actual conditions in agricultural landscapes to reveal the true extent of the effects of these...
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Occurrence and habitat selection of Common wood pigeon (\kur{Columba palumbus)} in the urban environment.
MELNYK, Andrii
The bachelor thesis focuses on the study of the abundance and habitat requirements of the wood pigeon (Columba palumbus) in different environments. It analyses the adaptation of the wood pigeon (Columba palumbus) to urban environments and its ecology in urbanized areas. The results show that most pigeons were found in the park zone, where most nests were also found. Fewer pigeons and nests were found in the urban environment compared to the park zone, while the agricultural habitat had the fewest pigeons and nests. The average number of pigeons per hectare and the number of nests per hectare were also calculated for each habitat and showed differences in population density between them. The work also focuses on factors affecting the occurrence and abundance of the wood pigeon (Columba palumbus) in urban environments, such as food availability, nesting sites and suitable climatic conditions. The aim of this thesis is to obtain more detailed information on the adaptation of the homing pigeon to the urban environment and its ecology, which may contribute to a better understanding of the relationships between the urban environment and bird habitat.
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Vliv tvaru potravních zdrojů na společenstva afrického koprofilního hmyzu
HELCLOVÁ, Michaela
This research focuses on communities of tropical dung-inhabiting insects and their relation to spatial parametres of their habitats, namely the dung pat shape and surface area. Study was carried out in South Africa. The aim of the study is to test differences in functional structure of coprophilous communities, its abundance and species richness across normal dung pats and dung pats with four times larger surface area. The results suggest that preference for habitat with different areas plays a crucial role for avoiding competition between dung-inhabiting insects.
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Monitoring výskytu nežádoucích plankonofágních ryb ve vybraných rybnících
CÍSLER, Jiří
Literature search deals with unwanted planktonophagous fish, their growth, food habits, and impact on the ecosystem. Undesirable fish affecting abiotic and biotic environmental conditions were investigated in the ponds Dehtář, Klec, Kvítkovický and Rod in 2018. The processed data describe and evaluate the development of fish that affect the water quality and zooplankton of the studied ponds.
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