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Effect of synurbanization on bird populations
Zeman, Vít ; Lučan, Radek (advisor) ; Šálek, Martin (referee)
Currently we can observe the expansion of human environment to the countryside all around the world. As the needs of man for space grow, so do the cities and urban environments expand. Ever more types of organisms are adapting to this environment, which allows us to record the changes that appear, either on the population or on the individual level. This Bachelor thesis is trying to summarize the existing knowledge of the effect of urbanization, and related synurbanization, on popualtions of birds, in the form of a literary research. This being an extensive topic, the thesis is focused on specific details, concerning primarily differences in population density, nesting success, condition of the birds, and predation pressure in urban and natural communities. Powered by TCPDF (www.tcpdf.org)
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Consequences of an infectious disease on genetic information in DNA sequences in bats
Nováková, Markéta ; Martínková, Natália (advisor) ; Lučan, Radek (referee)
Whitenose syndrome is an emerging fungal disease of bats causing massive dieoffs in North American populations. The fungus causes lesions on bat skin, mainly on noses, ears and wing membranes. The infection by the fungus is accompanied by serious disruption of metabolism and hibernation physiology that is lethal to bats in North America. European bats seem to survive the disease in greater numbers. Since the fungus is probably of European origin, this study assumes that bats in Europe have developed inheritable defence mechanisms to the disease. The infection by the fungus serves as a strong selective pressure. We tested sequences of 7 genes for signs of positive selection using maximum likelihood approach. We detected past positive selection in the gene for transglutaminase 1.
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Abundance trends and range dynamics in European bats.
Žabková, Klára ; Horáček, Ivan (advisor) ; Lučan, Radek (referee)
Bachelor thesis sumarizes available data about bat abundance in middle Europe, especially in the Czech republic. Populations of bats are usually dynamic, which is given by their high sensitivity to environmental changes. Many of these changes are man made, for instance landscape management, agricultural intensification or disturbing bats during hibernation. Impact of global warming on bat abundance and range distribution is also discussed, because it could explain the occurance of mediterranean species Hypsugo savii in Moravia In my thesis, I focus on possible causes of strong population decrease of Rhinolophus hipposideros in 70's in the middle Europe, which led to establishement of monitoring programms accross Europe. Project "Monitoring bats in underground hibernacula" has started in Czechoslovakia in 1969, and it has provided valuable and relevant data. I also compare methods for monitoring bats, because there isn't any effective universal method for censusing all species under all circumstances, due to their specific behavioral habits. Counting bats in underground hibernacula appears to be the most efficient, especially for species such as Rhinolophus hipposideros, Myotis myotis and Plecotus spp. Statistic methods are used to estimate colony size, Lincoln-Peterson method seems to be the most suitable...
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Social organization and mating systems in the genus Myotis
Wnuková, Lucie ; Jahelková, Helena (advisor) ; Lučan, Radek (referee)
We can find a big variety of social organizations and mating systems in order Chiroptera. The most common is polygamy where paternal care is typically missing. In temperate zone, there is seasonal change of climate what is influencing sociality and mating of Chiroptera which are adopting so called temperate cycle. This cycle is characteristic also for our species Myotis. During summer, females live in nursery colonies to make the nursing of the youngsters easier. In every specie of this order living in Czech Republic females are having only one cub. Shelters of the nursery colonies are for example in the cavities of trees, buildings or other gaps. Myotis myotis and M. Blythi, which originally occupied the caves, in our conditions are living in buildings. Number of individuals in the colony varies and depends on type of shelter. In species M. bechsteinii, M. nattereri and M. daubentonii, female colonies are disrupted into several sub-groups living in different shelters. This social organization is called fission-fusion. Even though males are being solitary during this period of time, we can find them also in female groups or they can form an only male group. Mating occurs usually in autumn when nursery colonies break up, probably during swarming. In winter, they are hibernating in their hibernacula which are...
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Social organization and communication of flying foxes focused on the genus Rousettus
Vašíčková, Pavla ; Jahelková, Helena (advisor) ; Lučan, Radek (referee)
Within the family Pteropodidae there are different types of social systems, depending on the species. Reproductive activity of Egyptian fruit bat (Rousettus aegyptiacus) is based on the latitude, when in milder latitudes individuals tend to be seasonally monoestry, southerly living individuals are less synchronous. Gestation lasts about four months and in most cases one young is born and mother cares about it. Egyptian fruit bats often inhabit caves, while there may live thousands of individuals and even more together. Pteropodidae are focused on plant food, which they choose according to the many criteria. Members of the genus Rousettus belong to the food generalists and their diet includes trees and herbs, from which they consume fruits, flowers, nectar, pollen, shoots and leaves. They were also observed by eating beetles of the family Scarabidae. Flying foxes of the genus Rousettus are special, because they orient by echolocation. They emit short broadband signals through the vibration of the language, whose length ranges from 50-100 s. From other chiropteran families they differ through the way of production the signals. In addition to echolocation senses of smell and sight are key in terms of communication. The smell is important mainly in attracting a partner, for mutual recognition between...
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Microclimate of different types of roosts in temperate bats: a review
Oppelová, Tereza ; Lučan, Radek (advisor) ; Jahelková, Helena (referee)
Chiropteran (Chiroptera) are still not so much explored order. It may be because of their night activity, hidden way of life and in large measure misunderstanding and mistrustfulness of people. Despite of progress during of last decade many of species are still insufficiently explored. Temperate bats are exhibited to many adverse conditions. Low temperature, temperature instability and seasonal food shortages forces bats to reduce their energetically costs to minimum. The need to adapt to these conditions leads to make new adaptations like torpor, social thermo genesis and hibernation. The important role is also choice of suitable roost with protection not only of bad weather and predators, but also with suitable microclimate, which helps to bats with energetically management.
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New findings of physiological and ecological aspects of hibernating bats
Ungrová, Zdislava ; Jahelková, Helena (advisor) ; Lučan, Radek (referee)
Bats can be found in almost all climatic zones. They have to deal with unfavorable conditions of environment to survive and reproduce sucessfully. Especially in temperate zones they have to deal with cold temperatures and lack of food during a winter season. To save energy bats enter a short, diurnal torpor or a hibernation. Usually, hibernation lasts all winter and is disturbed by short bouts of arousals. During both hibernation and torpor a physiological changes occur in bodies of bats. Body temperature decreases from endothermic levels, metabolic rates are reduced as well as respiratory rate and pulse. These changes are mainly influenced by weight and body size, diet, ambient temperature, sex and reproductive status. With the developement of new technologies, these changes can be measured more accurately than they have been in past, whether in a field or in a laboratory. But not all physiological processes are well explained. We have little knowledge especially about mechanism of arousal from hibernation. During awakening bats are infected by fungus Geomyces destructans that affects their immune system. In Norh America fungus causes a disease called White- Nose syndrome (WNS), that is responsible for death of millions of bats, especially endangered is Myotis lucifugus. In Europe, this disease is reffered...
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Population ecology of Daubenton's bat \kur{Myotis daubentonii}
LUČAN, Radek
Various aspects of population ecology of Daubenton?s bat (Myotis daubentonii) were analyzed based on long-term data (1968?1984 and 1999?2009) gathered in a single model study area (ca. 10 km2) in South Bohemia, Czech Republic. Among others, population structure, roosting dynamics, movements between roosts and long-term trends in numbers of bats were described. Results of the study on patterns in reuse of tree cavities suggest that tree cavities may be reused for many consecutive seasons and that this has to be taken into consideration by conservation practices. The results of the study on microclimate of one maternity and one male colony roosting in man-made structures revealed that microclimatic differences may be one of the key factors in roosting preference between the two sexes. Further, a profound effect of changing energetic demands in females during different phases of the reproductive cycle may greatly influence their activity rhytms. In further two studies, the effect of climate on reproductive parameters of bats and abundance of ectoparasitic mites was analyzed. The results suggest that climatic variation greatly influenced reproductive parameters and parasitation of Daubenton?s bats. Last but not least, the seasonal dynamics of parasitation by ectoparasitic mites and the possible effect on bats? condition was analyzed. It was found out that seasonal dynamics in abundance of parasites is adjusted to the reproductive cycle and roosting dynamics of its host.
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Alcathoe bat (Myotis alcathoe) in the Czech Republic: distributional status, roosting and feeding ecology
LUČAN, Radek
Between 2001 and 2008, we recorded Myotis alcathoe at nine sites within three distant areas in the Czech Republic. The species identification was confirmed with cyt b sequences and four distinct haplotypes were identified. All the localities exhibit surprisingly uniform habitat characteristics: (1) old full-grown oak-hornbeam forests, with (2) numerous large trees in advanced stages of decay are present, and (3) a very small to large water bodies and/or patches of riparian vegetation surrounded by the forest. Using radiotracking techniques, we discovered 27 day roosts of M. alcathoe, located mostly in big oak, birch and lime trees inside extensive forest stands. All roosts were fissures or small cavities in a tree trunk and in branches in the canopies, some 16 m above the ground. Bats preferred trees that were higher, had higher canopy and canopy basement and had larger diameter at breast height than other available trees. Roost trees were surrounded by lower trees with lower canopy basements than available trees. Roost trees were in a poorer condition than other available trees. Roosts were occupied by up to 83 individuals in July but usually single individuals were found in the roosts in September. In contrast to syntopic M. mystacinus and M. brandtii, M. alcathoe has never been found in an anthropogenic roost (except for a fissure in concrete electricity pole). Preliminary analysis of the diet showed that nematoceran flies were the most important prey item along with spiders, caddis flies, small moths and neuropterans. In the observed ecological characteristics, M. alcathoe markedly differs from other European species of the genus Myotis. Its restricted habitat requirements are perhaps responsible for an islet-like pattern of its distribution and suggest an essential conservation value of the habitats of its occurrence.
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