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Influence of urbanization patterns on the escape behaviour of birds
Dontová, Alena ; Mikula, Peter (advisor) ; Brlík, Vojtěch (referee)
Urbanization, i.e., the anthropogenic transformation of natural habitats into urban areas, has significant impact on the biodiversity. One of the key factors for successful animal survival in urban environments is the increase in their tolerance towards humans manifested by their decreased shyness. One of the field methods for assessing the level of the shyness across different individuals, populations, and species of animals is measuring their flight initiation distance. In this thesis, I focus primarily on birds, as their responses have been most extensively studied. Previous studies focused on differences in escape behaviour among birds mainly between urban and rural areas, and focused mainly on Europe and North America. However, human settlements vary in their history, size, population density, and other characteristics. Therefore, the observed patterns in bird behaviour may not always be universally applicable across all cities. In this thesis, through a literature review, I summarize how the escape behaviour of birds differs not only between urban and rural environments but also depending on the characteristics of human settlements, such as their size, history, degree of urbanization, the density of the local human population and the ecoregion. I found that the most important characteristics are the...
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Ecological consequences of seasonal bird migration
Brlík, Vojtěch
Environmental seasonality, and associated fluctuation in resource abundance, affects organisms throughout their life cycles. Periods of resource scarcity can be avoided by seasonal migration, strategy common in animals, including birds. However, the long journeys of migratory birds separate the stages of their annual cycles in space and time, and present them with a variety of challenges. Environmental conditions that migrants experience may have local effects, or may carry over across seasons, and have delayed impacts on individuals and populations. To better understand the interactions between migratory animals and their environment, we integrated individual tracking, environmental measures, and population data within a full annual cycle perspective. We contributed to the understanding that environmental conditions can affect migratory populations both en route and during stationary non-breeding periods, and that their effects can be observed on a continental scale. We also showed, across species and migratory flyways, that stages of the annual cycle are tightly linked during migration, but that these links weaken during prolonged non-breeding stationarity, with implications for individual success and future prospects under ongoing environmental change. To enhance the ability to trace animal...
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Ecological consequences of seasonal bird migration
Brlík, Vojtěch ; Procházka, Petr (advisor) ; Maggini, Ivan (referee) ; Piersma, Theunis (referee)
Environmental seasonality, and associated fluctuation in resource abundance, affects organisms throughout their life cycles. Periods of resource scarcity can be avoided by seasonal migration, strategy common in animals, including birds. However, the long journeys of migratory birds separate the stages of their annual cycles in space and time, and present them with a variety of challenges. Environmental conditions that migrants experience may have local effects, or may carry over across seasons, and have delayed impacts on individuals and populations. To better understand the interactions between migratory animals and their environment, we integrated individual tracking, environmental measures, and population data within a full annual cycle perspective. We contributed to the understanding that environmental conditions can affect migratory populations both en route and during stationary non-breeding periods, and that their effects can be observed on a continental scale. We also showed, across species and migratory flyways, that stages of the annual cycle are tightly linked during migration, but that these links weaken during prolonged non-breeding stationarity, with implications for individual success and future prospects under ongoing environmental change. To enhance the ability to trace animal...
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Movements within non-breeding grounds in terrestrial migratory birds
Kadlecová, Barbora ; Brlík, Vojtěch (advisor) ; Remeš, Vladimír (referee)
In recent years, the ecology of migratory birds has been a frequently studied subject especially due to modern tracking technologies. However, facts about behaviour of migratory birds on wintering areas are still limited. This thesis gathers information about movements within non-breeding grounds and stationary behaviour of terrestrial birds on wintering areas and about reasons of the movements. The majority of described movements occurred in Africa and South America and they were usually made by insectivorous songbirds. Majority of published data describes long-distance movements above 100 km. The most discussed factor of the movements was an availability of food which is affected by vegetation and the seasonal weather. Apart from the environmental factors I considered inner factors too, e. g. age or sex of birds. I also proposed some additional factors as a potential cause of movements within non-breeding grounds. The information about movements on wintering areas could serve as ground for further research of the behaviour of birds on wintering grounds, the influence of environmental conditions on the ecology of migratory birds and the information could also improve the protection of migratory birds.
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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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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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