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A range-wide assessment of carry-over effects within the full annual cycle of the Great Reed Warbler with a focus on sex and population differences
Brlík, Vojtěch ; Procházka, Petr (advisor) ; Bauer, Silke (referee)
Movements of long-distance migratory birds are frequently well timed and routed in order to maximise individual fitness. However, individual timing of events or environmental conditions experienced have a potential to carry over into subsequent annual cycle stages and may have delayed fitness consequences. Therefore, knowledge of these seasonal interactions is crucial to identify key periods and regions that limit survival beyond the breeding period and thus to fully understand population dynamics of migratory species. Despite current evidence for seasonal interactions, there is no detailed knowledge of the complex of relationships within the full annual cycle, differences between sexes and populations or impact of environmental conditions during moult in one species. To unveil this system of seasonal interactions within the annual cycle, we directly tracked 103 great reed warblers (Acrocephalus arundinaceus) using light-level geolocators from five breeding sites across the breeding range to obtain information on timing and positions of annual cycle events. We then combined this information with various remotely sensed habitat condition metrics and stable isotopic composition of feathers from the non-breeding grounds to identify and quantify carry-over effects within the full annual cycle. Our...
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Trophic structure of fish communities in the tributaries upstream of the Lipno Reservoir
Kofentová, Nikola ; Horká, Petra (advisor) ; Slavík, Ondřej (referee)
River obstacles, especially dams, are known to alter the natural environment in streams, which significantly impacts fish communities. The cyprinid species migrate from the reservoirs upstream to the reservoir's tributaries, where they may cause changes in the trophic structure of native fish communities. The aim of this study was to evaluate the trophic structure of the fish community composed mainly of cyprinid and salmonid species throughout seven localities in the Vltava River upstream of the Lipno reservoir. Stable isotope analysis was used to identify trophic positions, trophic niche width and trophic niche overlap between species. Trophic relationships of individual species were then evaluated to assess the potential for food competition. The trophic niche width of the salmonid species was significantly higher than that of the cyprinid species. Trophic niche overlap between salmonids and cyprinids was observed, with the most significant overlap being with both common dace Leuciscus Leuciscus and common roach Rutilus rutilus, suggesting a potential competition for food. The effect of the presence of cyprinids on the trophic niche width of salmonids was shown not to be statistically significant. From the perspective of protecting native salmonid species, there should be special attention paid...
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A range-wide assessment of carry-over effects within the full annual cycle of the Great Reed Warbler with a focus on sex and population differences
Brlík, Vojtěch ; Procházka, Petr (advisor) ; Bauer, Silke (referee)
Movements of long-distance migratory birds are frequently well timed and routed in order to maximise individual fitness. However, individual timing of events or environmental conditions experienced have a potential to carry over into subsequent annual cycle stages and may have delayed fitness consequences. Therefore, knowledge of these seasonal interactions is crucial to identify key periods and regions that limit survival beyond the breeding period and thus to fully understand population dynamics of migratory species. Despite current evidence for seasonal interactions, there is no detailed knowledge of the complex of relationships within the full annual cycle, differences between sexes and populations or impact of environmental conditions during moult in one species. To unveil this system of seasonal interactions within the annual cycle, we directly tracked 103 great reed warblers (Acrocephalus arundinaceus) using light-level geolocators from five breeding sites across the breeding range to obtain information on timing and positions of annual cycle events. We then combined this information with various remotely sensed habitat condition metrics and stable isotopic composition of feathers from the non-breeding grounds to identify and quantify carry-over effects within the full annual cycle. Our...
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Human Individuality in Bioarchaeology of Early Middle Ages: Conception, Methods and Interpretations
ZEMANOVÁ, Gabriela
The present work attempts to provide understanding of the issue of human individuality, identity and personhood in the Early Middle Ages on the basis of a literature review. The thesis also aims to describe the ways of study individuals in archaeology and in related fields with emphasis on bioarchaeological methods, which include determination of basic paleodemographic parameters, paleopathology, DNA analysis and stable isotope analysis. The application of these methods and the interpretation of their results in relation to human individuality are presented in three case studies from early medieval burial sites.
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Use of stable isotopes in feeding ecology of fish
Inquort, Vít ; Horká, Petra (advisor) ; Musilová, Zuzana (referee)
Cyprinidae is an important family of fish as far as ecological and economical aspects are considered. Studying feeding ecology of this family in aquatic ecosystems and integration of the findings into the overall image of trophic relationships are the fundamental prerequisite for the right interpretation of its ecological role. Stable isotope analysis is one of the methods capable of elucidating such relationships. In this thesis currently used methods and approaches in applications of stable isotope analysis in feeding ecology of fish are summarized. These vary among individual authors and include sampling of different fish tissues and different methods of preparation of samples before analysis, e.g. lipid extraction or carbonate removal. Certain mechanisms and phenomena which need to be taken into account to avoid biased results are also outlined in this thesis, among all tissue turnover and isotopic routing in particular. In the thesis current findings on food resources, trophic level and trophic niche of cyprinid fishes in freshwater ecosystems based on stable isotope analysis were summarized as well. Despite such findings being partial to date and the potential of the method not yet being fully exploited in many species, stable isotope analysis provide an important and useful tool alongside...
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Towards a better understanding of ungulate diets: a methodological approach
Holá, Michaela ; Červený, Jaroslav (advisor) ; Stádník, Luděk (referee)
Populations of European ungulates have grown substantially over recent decades, resulting in considerable environmental and socio-economic impacts. Availability and quality of natural and supplemental food sources are among the main factors driving their population dynamics. Detailed knowledge of feeding strategies of management-targeted species is therefore of primary importance for their successful management. Over time, methods to study the feeding strategies of animals have also evolved considerably but each has its advantages as well as limitations. This doctoral thesis uses a combination of traditional methods (i.e. stomach content analysis) and novel methods (i.e. stable isotope analysis, near infrared reflectance spectroscopy) to achieve a better understanding of feeding strategies of two important ungulate species (i.e. wild boar and red deer) in the Czech Republic, where their populations are on the rise and supplementary feeding is rampant. Next, this dissertation aims to introduce and to establish a basis for these novel methodological approaches for the study of free-ranging individuals. In this respect, it also addresses methodological issues related to their application in this field.
The diet composition of wild boar was investigated by examining stomach contents in order to identify their dependence on food resources of human origin (i.e. agricultural crops and supplemental foods). Foods of human origin were the dominant diet type and constituted the bulk of the diet of wild boar throughout the year. A necessary prerequisite for application of stable isotope analysis is the trophic discrimination factor (i.e. systematic difference between the isotopic composition of the consumer tissues and that of the diet), which was experimentally determined for stable carbon and nitrogen isotopes, the two most commonly used in ecology, in hair tissue of wild boar and red deer. Furthermore, possible sources of variation (such as sex, age, body weight, and lactation) on isotopic discrimination were investigated. The results of the experiments provide a starting point for the successful use of stable isotope analysis in field studies on wild boar and red deer. Finally, application of near infrared reflectance spectroscopy was proven to be useful in measuring faecal indices of food quality for red deer. The results of this thesis will contribute towards efficient management of wild boar and red deer in the Czech Republic.
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Archaeozoology of the Neolithic of Bohemia
KOVAČIKOVÁ, Lenka
An archaeozoological analysis of the assemblages of animal bones and teeth of Neolithic (Linear and Stroked Pottery cultures; approx. 5500-4200 BC)settlements in Bohemia, provide new elements on the way of life of early farmers. By means of study of animal bones and teeth we can specify the role of domestic and hunting animals in the Neolithic economy, define the herd management strategies for main domestic animals and focus on the environmental reconstruction and investigation of births distribution of domestic animals (for exemple of cattle in the case of this study) through the analysis of the carbon and oxygen isotopic compositions of fossil tooth enamel bioapatite. To achieve these objectives, we can use, except standard archaeozoological methods and stable isotope analysis, more specific procedures, e.g. determination of damaged bones of animals using the ELISA test.
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