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Diversity and abundance of birds in 3D space of Žofínský prales primary forest
Kučerová, Eliška ; Hořák, David (advisor) ; Korňan, Martin (referee)
Bird species are specialized in diverse types of environments. Considering for example forest species, this does not mean that all species inhabit the same ecological niches. Some species occupy undergrowth while others prefer treetops. Some birds are bound to clearings and other gaps in forest cover, and other species require old trees with cavities. Primary Central European mixed forest is not a homogenous environment. But, on small spatial scales, the environment is very heterogeneous. We get an unprecedented variety of habitats especially when including the forest vertical dimension, which birds use much more than it is usually considered in studies. This diploma thesis describes in detail the bird assemblage in the Czech oldest nature reserve NPR Žofínský prales in which vegetation research is currently in progress. However, research dealing with bird mapping in forests still rarely consider the vertical dimension of the environment. Most bird censuses focus on the diversity of species at a site but usually do not include abundance of individual species. I, therefore, focused on a detailed mapping of the bird community on a 50-hectare area in NPR Žofínský prales. During the census, each bird and each bird's exact position in the 3D space of the forest were recorded. Special attention is paid...
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Determinants of abundances in terrestrial vertebrates
Kundelová, Tereza ; Storch, David (advisor) ; Sedláček, Ondřej (referee)
The abundance of animals differs between species, however, they also vary in area and time. These differences relate to biotic and abiotic factors as well as to ecological characteristics of particular species. Studies focusing on these factors are aiming to answer the question; how and what influences the abundance of these species. Besides clarifying the dependence of abundance on particular factors, studies also try to ascertain which key factors are necessary for the determination of abundance. The most frequently studied factor is body size, but trophic level, specialization, net primary productivity, and competition also play a significant role in determination. However, all these factors explain only a small proportion of interspecific variability in abundances. This thesis focuses on terrestrial vertebrates; however, mainly on birds and mammals; since, these two taxa are the most studied. Key words: abundance, population density, terrestrial vertebrates, body size, competition, energy flux
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Distribution and habitat preference of the Ortolan Bunting in the Czech Republic
Zeman, Vít ; Lučan, Radek (advisor) ; Šťastný, Karel (referee)
The Ortolan Bunting (Emberiza hortulana) is a farmland bird species, whose population size has declined very sharply in recent decades, especia ll y in Western and Central European countries. The aim of our study in 2015 was to record where the last populations of this critically endangered species in the Czech Republic are located and also what habitat the species associated with. We examined nine areas (925 km2 in total). Two main areas of occurrence (surface mines in northern Bohemia and farmland landscape of Silesia) and two small isolated populations in central Bohemia were registered for this species. In contrast, observations in some traditional areas of its occurence (České středohoří in northern Bohemia, Hovorany-Čejkovice region in southe r n Moravia and Javoricko region in Silesia) were negative. Altogether, we counted 75-79 singing males. Our estimation of the size of the Czech population in 2015 is 75-100 singing males, which indicates further population decline compared to the last mapping in 2001-2003. Furthermore, habitat associat io ns were investigated at two spatial scales and we made habitat compar is o n between farmland and post-mining landscape. Our research highlights a high degree of flexibility in habitat selection of Ortolan Bunting and also positive association with high...
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Zhodnocení faktorů ovlivňujících intenzitu poškození porostů na území podniku Kolowratovy lesy
Svoboda, Tomáš
The work assesses the factors affecting the intensity of damage to vegetation Europen deer and sika deer on the holding Kolowrat forests. The study is to compare the population density of each game species, found less used method of counting dung piles on the strips transect, where the resulting states do not correspond to states of documents supplied by the owner of the hunting grounds. The observed population density is further compared with the number of trees damaged by bark consumption. The result of this comparison is the finding that the damages do not increase proportionally with the number of animals. The work concludes with a proposal of measures to reduce damage, arising out of tree species in the surveyed area.
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Environmental determinants of bird species richness and population densities in sub-Saharan Africa
Dubský, Marek ; Sedláček, Ondřej (advisor) ; Reif, Jiří (referee)
The research of factors influencing bird's species diversity and abundance will allow us to manage the landscape in the way to create suitable conditions for survival of species. For the purposes of this work, I divided bird assemblages into 3 groups on local level: forest birds, shrubland birds and grassland birds. The forest bird species were most influenced by height of canopy, its compactness and fragmentation of the forests. The size of the fragment, fragment matrix, isolation of the fragment and birds sensitivity to edge effect were deciding factors of number of species and individuals in each fragment. The shrubland birds were most influenced by vegetation structure in meaning of presence of shrubs, trees and grassland. They were also influenced by vegetation species composition, frequency and form of disturbances (fire, grazing), they reacted positively to transformation of landscape into agroecosystems and they reacted negatively to shrub encroachement. Grassland birds reacted to various height of grass, they reacted negatively to presence of trees and shrubs and also to disturbances caused by human. It is the least studied group of birds in Africa. As fot the elevation gradient, the lowland assemblages of birds changed to mountains assemblages at attitude of about 1250 above the sea...
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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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Abundance-distribution relationship: the importance of ecological specialization
Farkač, Jan ; Hořák, David (advisor) ; Reif, Jiří (referee)
6 Abstract The relationship between local abundance and regional distribution is a widespread ecological pattern. It is frequently reported to be positive, however exceptions have been evidenced. But the explanation is not clear at all. There are many of mechanisms explaining this relationship, from those related to statistical issues, those explaining it by metapopulation dynamics, to rates of ecological specialization, which are the most frequently considered. But it is likely that certain mechanisms work together. One of the principal hypotheses is the resource breadth hypothesis, which claims that generalists tend to be more abundant and widespread whereas specialists occur in small range and less abundant. There are two ecological relationships linked to ecological specialization. It is a niche breadth-range size relationship and niche breadth-abundance relationship. While the former is well documented, the information about latter is rather scarce. This thesis sums up existing studies about distribution-abundance relationship with a special focus on importance of ecological specialization. Key words: geographical distribution, local density, niche breadth, ecological specialization
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Diprionids of the genus Gilpinia living on spruce in the Czech Republic
Penzešová, Markéta ; Lukášová, Karolína (advisor) ; Holuša, Jaroslav (referee)
This bachelor thesis deals with the occurrence of diprionids Gilpinia species associated with the spruce throughout the Czech Republic. In 2015 there was research carried out to map the abundance and frequency of the diprionids. There were Malaise traps - model Townes (1972) installed on 12 locations in spruce forests in early May. There were samples picked up in irregular intervals of 14 days until mid-July. Once all the samples had been collected in the laboratory of CULS in Prague the diprionids were sorted from all the other insects and their type and gender was determined. In total there were 4 specimens caught from Gilpinia polytoma out of which 2 were males and 2 were females. No other diprionids Gilpinia species were found. The results were analysed statistically and the catches were compared with the catches between years 1997-2003 on some identical locations. Further this bachelor thesis deals with leaf-eating insects, bionomic of species found in the Czech Republic. From the results of our study and other studies made in other countries we do not expect the gradation or significant forest damage by these pests in forthcoming years in the Czech Republic. Conversely bionomics of some diprionids on spruce seems to be quite unstudied and finding them can be thought of as rare.
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Density dependent growth of brown trout Salmo trutta in oligotrophic streams
Závorka, Libor ; Slavík, Ondřej (advisor) ; Frouzová, Jaroslava (referee)
This thesis deals with the influence of population density on the growth of brown trout Salmo trutta. The research was carried out in the Šumava National Park in the river basins of two oligotrophic streams, the Vydra and the Křemelná. Data has been collected between years 2005 and 2010, every spring and autumn. Fish were caught via electrofishing and the length and weight of each individual were measured. Every individual caught was marked in a unique way. A few samples of scales were taken from some of them. The scales were fixed into laboratory slides, scanned and measured by graphic software. According to the differences between annual lamellas density, the age and the annual growth of individual's body length were estimated. Thanks to these results a negative relationship between the individuals' of age 1+ growth rate and the population density was confirmed. The importance of this thesis is mainly in comparing the influence of different spatial and time definitions of population on this relationship. The influence of the population density in spring (the initial time of the growth period) was proved to be essential for the growth rate. This fact suggests the importance of compensation growth intensity after the long period of winter for individual's general growth under conditions provided by...
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Population density of the red deer (Cervus elaphus) and forest damage in Křivoklát region (Central Bohemia, Czech Republic)
Faifr, Michal ; Červený, Jaroslav (advisor) ; Mrkvičková Kořanová, Diana (referee)
The aim of this study was to determine the population density of deer in the area Křivoklátsko. To detect a population density was used counting dung piles. The work is also characteristic of the whole monitored area, and the deer (Cervus elaphus), which Krivoklatsko abundant. This work also discussed the various census followed by a focus on the method of counting dung piles. Furthermore, it evaluates the incidence not only of deer in forests and damages, as well as the presence of sika deer (Cervus nippon), roe deer (Capreolus capreolus), wild boar (Sus scrofa) and fallow deer (Dama dama) and damage them caused. In this study also highlighted the amount of catch deer in both areas, compared with known population density of deer.
In the discussion we discussed the pros and cons of methods of counting dung piles and accuracy of results.
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