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How do bird species richness and abundance differ between military training areas and surrounding landscape? A case study from the Hradiště military area
Bušek, Ondřej ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Since the beginning of the 20th century human land use changed drastically in Central Europe. These changes included: homogenization of the landscape mosaic, intensification of agriculture, urbanization and land abandonment. In turn, these changes affected bird species and perhaps most significantly manifested in population decline of open habitat birds. Therefore, it is important to investigate sites, which were not affected by the changes mentioned above, such as military training areas (MTAs) - places dedicated to training of armed forces. Previous studies have shown that MTAs seem to host remarkably high bird diversity and abundant populations of bird species of conservation concern. This may be caused by two major factors. First, closure of MTAs to all human activies besides military training spared them of the landscape changes mentioned above. Second, the military training itself produces a very heterogeneous habitat mosaic that allows coexistence of many species with different ecological requirements. To my knowledge, no study compared bird assemblages between MTAs and surrounding landscape directly. At the same time, such data are crucial to assess the value of MTAs for bird conservation reliably and, as a consequence, they enable to think more deeply about mechanism generating this value....
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Bird mortality at transparent barriers
Houdová, Monika ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Bird mortality at transparent barriers (noise barriers or common house windows) is undoubtedly very important environmental issue, because of the rapid development of human society and even more rapid growth of very dangerous places for birds. At this time there is no review article yet, that would synthesize each sub-study on the extent to which individuals can die on those obstacles, which factors are critical for the ability of obstacle avoiding, how much collision threaten the vitality of bird populations and if we can prevent such unintended damage. This bachelor thesis handle with these questions as a literary review. From the available information we can suggests that the most important factor is migration behavior of birds, individuals migrating through the night are much more at risk than those migrating during the day, mostly because of light pollution, which can confuse them. The most dangerous time of year in this direction is clearly autumn, and that also relates with migration. Population losses caused by collision to the transparent barriers can be up to 20 % of the total population per year. Thesis in addition to a summary of available information on the issue proposes and evaluates possible preventive aplications, which may further serve to effective conservation for birds among...
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Ecological and ethological aspects of bird-building collisions
Semeráková, Anna ; Sedláček, Ondřej (advisor) ; Koleček, Jaroslav (referee)
Collisions with artificial structures represent one of the most significant cause of bird mortality worldwide. Accounting for hundreds of millions bird deaths each year, bird-building collisions represent a particular problem. Although the bird's vision system is perfectly adapted to the orientation during fast flight, birds are often confused due to the transparency or reflectivity of the glass. Moreover, light pollution of urban areas interferes with the physiological geomagnetic and polarized light compass in birds, which causes the night migrants to disorient. The bird-building collision frequency variates in time and space. Throughout the day, largest number of fatal collisions occurs during early morning. Throughout the year, the peak in the numbers of fatal strikes appears in the course of autumn migration. Local species abundance did not appear to be the most important predictor of collision probability. Species traits making birds highly prone to collisions are small body size, high flight speed, long distance of migration and feeding strategy requiring rare and temporary food sources. Aggressive males during the mating period and inexperienced post-fledging juveniles are among the most vulnerable individuals. Based on taxon-specific ecological traits, some bird families were identified to...
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Habitat specific population densities in animals: a concept review
Šlosarová, Dita Afrodita ; Hořák, David (advisor) ; Koleček, Jaroslav (referee)
Population density estimate can be expressed through many different ways. Various concepts differ above all in area of the survey, which is influenced by aim of the research and the purpose of the results. Commonly used crude density reports the abundance of individuals per unit of a geographic space. Ecological population density concept, on the other hand, expresses the number of individuals within an ecological space, such as specific habitat type, hence the usage of habitat-specific name as well. Ecological density in comparison to crude density, often shows considerably higher population density. It it clear that higher values of ecological density appear to be caused either by smaller area of the survey or by selection of the area by prior knowledge of space distribution of individuals Although some authors like Elton, Mohr and Damuth attempted to define different concepts, there is still no united and strict definition of ecological density. Therefore, we meet with many variations and a broad scope of utilization, that are all collectively named ecological or habitat specific density. While using the habitat-specific density it is crucial to consider many aspects such as the body mass of the individuals, which correlates to size of the area of occurrence, their habitat preferences and...
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Bird population changes from a historical perspective: a case study from the Czech Republic
Szarvas, Filip ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Numerous studies focused on the changes in breeding bird populations in the Czech Republic exist, however, these studies are based on data from 1980s onwards. Such studies investigate the effects of environmental changes on various bird groups defined by their ecological traits. Although these studies provided important insights into bird population drivers, considering the start of 1980s as a baseline for comparisons with the current conditions is questionable since the underlying drivers most likely acted for longer time. To bridge this knowledge gap, the goal of my study is to create a comprehensive dataset covering changes in bird populations over three time periods: 1950s/60s, 1980s and recent time (2014-2018) based on the memories of ornithologists who witnessed these times. The next goal is to establish whether the decrease of some species dates from the last 40 years, or whether it predates this period. The results of my study show that certain groups of birds according to their ecological requirements disappear from the Czech landscape faster than other groups. In the groups of species classified by their environmental requirements, the most rapidly disappearing are species bonded to agricultural landscape and urban species. According to the food requirements, the fastest decreasing are...
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Bird mortality at transparent barriers
Houdová, Monika ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Bird mortality at transparent barriers (noise barriers or common house windows) is undoubtedly very important environmental issue, because of the rapid development of human society and even more rapid growth of very dangerous places for birds. At this time there is no review article yet, that would synthesize each sub-study on the extent to which individuals can die on those obstacles, which factors are critical for the ability of obstacle avoiding, how much collision threaten the vitality of bird populations and if we can prevent such unintended damage. This bachelor thesis handle with these questions as a literary review. From the available information we can suggests that the most important factor is migration behavior of birds, individuals migrating through the night are much more at risk than those migrating during the day, mostly because of light pollution, which can confuse them. The most dangerous time of year in this direction is clearly autumn, and that also relates with migration. Population losses caused by collision to the transparent barriers can be up to 20 % of the total population per year. Thesis in addition to a summary of available information on the issue proposes and evaluates possible preventive aplications, which may further serve to effective conservation for birds among...
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How do bird species richness and abundance differ between military training areas and surrounding landscape? A case study from the Hradiště military area
Bušek, Ondřej ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Since the beginning of the 20th century human land use changed drastically in Central Europe. These changes included: homogenization of the landscape mosaic, intensification of agriculture, urbanization and land abandonment. In turn, these changes affected bird species and perhaps most significantly manifested in population decline of open habitat birds. Therefore, it is important to investigate sites, which were not affected by the changes mentioned above, such as military training areas (MTAs) - places dedicated to training of armed forces. Previous studies have shown that MTAs seem to host remarkably high bird diversity and abundant populations of bird species of conservation concern. This may be caused by two major factors. First, closure of MTAs to all human activies besides military training spared them of the landscape changes mentioned above. Second, the military training itself produces a very heterogeneous habitat mosaic that allows coexistence of many species with different ecological requirements. To my knowledge, no study compared bird assemblages between MTAs and surrounding landscape directly. At the same time, such data are crucial to assess the value of MTAs for bird conservation reliably and, as a consequence, they enable to think more deeply about mechanism generating this value....
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