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Flight initiation distances and life histories in birds: comparison of intra- and interspecific approaches
Brzobohatá, Tereza ; Albrecht, Tomáš (advisor) ; Klvaňa, Petr (referee)
Information about the distance, in which the birds flee from predators, may help us to better understand avian escape behavior and stress responses. These distances are influenced by many life-history traits and related factors, both on intraspecific and interspecific levels. This bachelor's thesis is trying to summarize the current knowledge of agents influencing flight initiation distances (FID) of birds, in the form of a literary research. The first section deals with antipredator behavior in birds, and explains methods that are used for measuring critical distances. In the second part of thesis, factors affecting flight initiation distances on intraspecific level are described. The main emphasis is on impact of age characteristics, body sizes, reproductive investments and geographical distribution. The last chapter summarizes the information about relationships between FID and life-history traits on interspecific level. The age of the individual, levels of stress hormones, the effect of the season and biotop are described in detail. Powered by TCPDF (www.tcpdf.org)
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Long-eared owl (Asio otus) migration within Central Europe
Fraitágová, Iveta ; Řezníček, Jan (advisor) ; Klvaňa, Petr (referee)
The aim of the present thesis is to give a review of the ringing recoveries of the Long - eared owl (Asio otus) in the territory of the former Czechoslovakia and the Czech Republic. The bird ringing data used in this thesis come from the archive of the National Museum in Prague. The parts of the thesis are as follows:1) history of the ringing in the Czech Republic; 2) bird adaptation on the flight and migration; 3) control of the migration; 4) the data of the Long- eared owls ringed as the young birds in the nest (pulli); 5) the data of the Long - eared owls ringed as adults (ad), that were caught and checked during their wintering in the Czech Republic; 6) the recoveries of the Long- eared owls ringed by various European Bird Ringing Centres and found in the Czech Republic; 7) cause of the mortality of the Long eared owl;8) census of the Long - eared owl recoveries in the Czech Republic from 1934 till 2011 (appendix). Key words: Migration, the Long-eared Owl, Ringing, Ringing Recoveries, Mortality
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Altitudinal migrations in animals and their study methods
Zenklová, Tereza ; Sedláček, Ondřej (advisor) ; Klvaňa, Petr (referee)
Migration as a response to the seasonality of the environment is common in many animal taxa. Strong fluctuation of the climate is usually connected to regions in the temperate zone, quite common is in the tropical regions as well. Typically, it is even more pronounced in high altitudes. In such environment, many animals could migrate altitudinaly as a response to changes in the climatic conditions or food abundance. But determinants of altitudinal and long-distance latitudinal migrations could be different. The objective of this work is to determine factors influencing altitudinal migrations in diverse taxa (particularly in birds and bats) and in different biogeographical regions. I am trying to find some common features of migrating species, such as diet or temperature and rain tolerance. Especially tropical species are partial migrants, which means that only some individuals of the population migrate. I will discuss common features of such migrating infividuals. Study methods of altitudinal migration will be a part of this research as well. The work will be primarily concentrated on tropical regions.
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Sex and age differences in migration in Anatidae
Prokešová, Erika ; Musil, Petr (advisor) ; Klvaňa, Petr (referee)
The thesis is aimed at intraspecific differences in migratory birds of the order Anseriformes, family Anatidae. It is especially focused on the differences affected by sex and age too. Most of the Anatidae forms its pair-bonds early, not on the breeding grounds like other bird orders do, but on the wintering grounds already. However, it was observed that in some species both sexes don't migrate to the same wintering grounds. Moreover, there are geographical differences between each population really big, so it's not easy to investigate this phenomenon. The adult sex ratio is male-skewed because of their greater survival rate resulting in greater selection by females, especially in species which form their pair-bonds in the end of the winter season. This thesis summarizes the factors responsible for migratory differences during the non-breeding season, then compares conclusions of the studies conducted in this issue between individual subfamilies and tribes of the Anatidae. Key words: sex-dependent migration differences, age-dependent migration differences, early pair formation, Anserinae, Anatinae, dabbling ducks, diving ducks.
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Impact of intraspecific brood parasitism on reproductive success of barn swallow females
Hodanová, Jana ; Jelínek, Václav (advisor) ; Klvaňa, Petr (referee)
Intraspecific nest parasitism is one of the alternative reproductive strategies of birds, in which a parasitic female lays her eggs in the nest of another female of the same species, thereby increasing her reproductive success while avoiding any demands on parental care. In this paper, I used data from long-term monitoring of a population of the barn swallow, Hirundo rustica, in the Třeboň region. Using genetic analysis, I determined all parasitic and non-parasitic females that occurred in this socially monogamous species in the studied populations with regard to the difference between classical parasitism and quasi-parasitism. In my thesis, I also described the egg-laying timing of parasitic females in context of host egg-laying, compared qualitative characteristics of individual parasitic and non-parasitic females, and investigated the effect of parasitism on female reproductive success. The results suggest that female parasitism is a relatively common phenomenon in swallow populations and that the occurrence of parasitism cannot be predicted by the quality of females. However, I found a positive relationship between parasitism and female reproductive success. Finally, several ways of timing of parasitism have been observed. Key words Barn swallow, conspecific brood parasitism, hypotheses,...
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Migratory divide in European birds
Branišová, Dominika ; Hořák, David (advisor) ; Klvaňa, Petr (referee)
This bachelor thesis deals with migatory divide in European birds, i.e. the contact zone between two population of one species differing in migration path and wintering site. It also comments on related methodological approaches, such as ringing, emlen funnels, satellite tracking or stable isotopes analysis. Between species with best documented migratory divide belong for example blackcap (Sylvia atricapilla) or willow warbler (Phylloscopus trochilus). In birds, many mechanisms are responsible for the creation of the migratory divide: (i) the colonization of Europe after the last glaciation by two or more populations of one species living in refugias, (ii) the presence of natural barrier separating populations and affecting their migration patterns, (iii) the impact of climate change as it causes selection pressure on a certain part of the population and creates differences in migratory behavior. Among key factors responsible for maintaining the divide belong mechanisms ensuring the low gene flow between populations, such as: (i) selection against hybrids or assortative matting. In non-passerines, also other mechanisms have been reported, such as learning migration route in juveniles from adults. Existence of migratory divides is supported by the selection pressure to find an optimal migration strategy,...
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Phenotypic divergence between farmed and wild populations of mallard (Anas platyrhynchos)
Pechmanová, Hana ; Kreisinger, Jakub (advisor) ; Klvaňa, Petr (referee)
Large-scale restocking of hand-reared individuals can pose a risk for wild populations. A decrease in the abundance of the Mallard (Anas platyrhynchos) has led to game-farming and the release of hand-reared mallards for hunting purposes in many states, including the Czech Republic. Different selection pressures and evolutionary processes affecting farm animals may cause genetic and phenotypic divergence between these populations. The aim of this thesis is to find out if the phenotype of ducklings hatched from eggs in game-farm and wild population varies in growth, hematological, immunological and behavioral traits, in controlled conditions using common garden experiment. Game-farm individuals were heavier and characterized by larger growth, even when controlled for different egg size. Individuals hatched from eggs of wild origin, on the other hand, had a larger bill and tarsus in relation to body size. An analysis of hematological traits, such as the differential number of leucocytes and immature erythrocyte count in relation to the overall numbers of erythrocytes, displayed complex relations during ontogenesis. The heterophil/lymphocyte (H/L) ratio and the immature erythrocyte count were characterized by dynamic changes in the course of development of juveniles and by interaction with...
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Flight initiation distances and life histories in birds: comparison of intra- and interspecific approaches
Brzobohatá, Tereza ; Albrecht, Tomáš (advisor) ; Klvaňa, Petr (referee)
Information about the distance, in which the birds flee from predators, may help us to better understand avian escape behavior and stress responses. These distances are influenced by many life-history traits and related factors, both on intraspecific and interspecific levels. This bachelor's thesis is trying to summarize the current knowledge of agents influencing flight initiation distances (FID) of birds, in the form of a literary research. The first section deals with antipredator behavior in birds, and explains methods that are used for measuring critical distances. In the second part of thesis, factors affecting flight initiation distances on intraspecific level are described. The main emphasis is on impact of age characteristics, body sizes, reproductive investments and geographical distribution. The last chapter summarizes the information about relationships between FID and life-history traits on interspecific level. The age of the individual, levels of stress hormones, the effect of the season and biotop are described in detail. Powered by TCPDF (www.tcpdf.org)
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