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Synurbanization in wood pigeon (Columba palumbus) and Eurasian magpie (Pica pica)
Tesařík, Jáchym ; Lučan, Radek (advisor) ; Hořák, David (referee)
Both Eurasian magpie and Wood pigeon are typical synanthropic bird species. By studying the available sources, I found that during their synurbanisation, both species have undergone several changes that have facilitated their transition from rural to urban habitats. Due to their adaptability, they have no problems colonizing urban environment and have managed to occupy new and diverse range of nest sites. Thanks to synurbanisation, both Magpie and Wood Pigeon have been able to expand their range and increase their overall abundance. Possibly the biggest threat to urban populations of both species is nest predation, which locally leads to declining population trends and reduced breeding success. Because of predation pressure and the adaptability of both species, I think we can expect not only an increase in abundance and population density in their urban population in the future, but also the occupation of new and more diverse nesting habitats in closer proximity to human settlements.
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Changes in distributional range and ecology of bats realated to climate change
Pavlíková, Barbara ; Lučan, Radek (advisor) ; Bartonička, Tomáš (referee)
In the last few decades bats are affected by climate change. Changes in average temperatures affect their morphology, phenology, diversity and distribution. Changes in biotopes caused by anthropogenic influences are responsible for the loss of shelters and connectivity of habitats. Empirical data show us that the range expansion of many bat species are gradually shifting to higher latitudes or altitudes. Mathematical models predict that the bat diversity and richness around the world will decline. Some species will shift their ranges and some will shrink their range or even become extinct. Key words: chiroptera, bats, range shift, bioindicators, climate change
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Swarming and hibernation of bats in scree fields and talus slopes
Legát, Jakub ; Lučan, Radek (advisor) ; Andreas, Michal (referee)
This literature review attempts to summarize the knowledge on swarming of temperate bats. It focuses on the characteristics of the term swarming and the history of research on this behaviour in the Czech republic and worldwide. It describes in some detail the species that participate in this behaviour, defines the period when bat swarming take place and discusses the factors that influence this behaviour. The second part of the paper summarizes information on swarming and hibernation of bats in scree fields and talus slopes. However, there is very little information to date on whether and in what quantities bats use this habitat during swarming and hibernation period. This thesis discusses existing surveys on this issue and is designed as a theoretical overview for the field research that author intends to undertake during his master's degree.
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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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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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Methods in research of insects mobility
Jor, Tomáš ; Hadrava, Jiří (advisor) ; Lučan, Radek (referee)
Mobility is one of the basics characteristics of the insects populations. This bachelor thesis presents a compendium of methods used in research of insects mobility. In the first part are described methods of marking individuals utilized for Mark-Recapture studies aiming to study insects movements. First are presented the indirect methods of individuals tracking, further the methods of direct tracking of insects using a radio-telemetry are described. In the second part the thesis focused on modeling of insects mobility using dispersion functions with connection to metapopulation dynamics and a dispersion itself. Difusion model based methods and simpler estimates of movemensts are also presented in this part. Key words: Insects, Mobility, Mark-Recapture, Modeling
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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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Effect of urban gradient on composition of bat communities in Central European landscapes.
Kočí, Jakub ; Lučan, Radek (advisor) ; Andreas, Michal (referee)
Bats (Chiroptera) are usually considered as a group greatly endangered by destructing their habitats through the human activity. However, a significant part of bat species at the central Europe use human buildings as shelters, moreover the natural shelters are marginal or unknown in several species. Considering the linkage of the great part of our bat species to the fragmented area and in connection with a long term human influence on the central european landscape we ask whether at least part of our species see human activity through providing proper shelters as positive. Based on the analysis of landscape structure and ruggedness effect on density, diversity and population structure of bat assamblages acquired by standardized mist net captures located in lowlands (elevations below 500 m) of Czech Republic (204 localities, 3585 bats, 22 bat species), we found that even though most of reactions were species specific and few species seemed to be positively associated with urban environments, most of the bat species rely on the broad-leaved forest cover and other natural habitats such as water bodies. The most significant factor influencing sexual segregation for bats was ruggedness of surrounding landscape. Keywords: Bats, Chiroptera, fragmentation, Europe, temperate zone
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Methods in research of insects mobility
Jor, Tomáš ; Hadrava, Jiří (advisor) ; Lučan, Radek (referee)
Mobility is one of the basics characteristics of the insects populations. This bachelor thesis presents a compendium of methods used in research of insects mobility. In the first part are described methods of marking individuals utilized for Mark-Recapture studies aiming to study insects movements. First are presented the indirect methods of individuals tracking, further the methods of direct tracking of insects using a radio-telemetry are described. In the second part the thesis focused on modeling of insects mobility using dispersion functions with connection to metapopulation dynamics and a dispersion itself. Difusion model based methods and simpler estimates of movemensts are also presented in this part. Key words: Insects, Mobility, Mark-Recapture, Modeling
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Bird Communities Along the Altitudinal Gradient on Mt. Cameroon: Perspectives from Mist Nets
Petruf, Miroslav ; Sedláček, Ondřej (advisor) ; Lučan, Radek (referee)
in English Mt. Cameroon is a hotspot of diversity and endemism in Africa. Recent research of avian bird communities along the elevational gradient on Mt. Cameroon based on point counts has shown low-elevation plateau of species richness. At the same time, range-restricted montane populations of birds on Mt. Cameroon are unusually abundant if compared to lowland species. I analysed data on community composition, species richness and abundance of birds using an alternative quantitative method - 200 m of understory mist nets erected for three consecutive days across seven elevational plots along the forested gradient of the Mt. Cameroon. First, I looked at the technical limits of this method and confirmed the general opinion that they are better at detecting small birds below 33 g, and that they mostly detected fewer individuals after the first day and always detected fewer new species after the first day of mist-netting. Mist nets detected high proportions of ground-feeding and understory birds and low proportions of birds foraging in higher strata in the lowland forest, which has a scarce understory and a dense canopy. Mist nets recorded similar proportions of birds foraging in all forest strata in the vastly open mid-elevation forest, which has a dense herbaceous understory. They detected higher...
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