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Bird communities in the invasive Knotweed (Reynoutria sp. div.)
Hajzlerová, Lenka ; Reif, Jiří (advisor) ; Sedláček, Ondřej (referee)
Although it is widely recognized that exotic plant invaders can affect diversity of native plant communities, a few studies of natural systems concern about the nature abundance and diversity loss and the associated consequences for higher trophic levels. Little is known impact of exotic riparian plant on higher-order consumers, such as birds. Such is requirement to understand underlying mechanisms of invasive processes and formulating effective management strategies. We examined interaction between invasive knotweed (Reynoutria sp. div., next only knotweed) and bird communities. We recorded occurrence of birds along three rivers in riverbanks that were either dominated by native vegetation or invaded by knotweed. Birds were recorded in breeding seasons in 2011 and 2012 near town Frýdek-Místek and Valašské Meziříčí. We interested especially in (i) how knotweed composition within riparian systems affects avian communities and (ii) what common bird characteristics are influenced by knotweed. Our outcome found positive effect of Marsh Warbler (Acrocephalus palustris) and Great Tit (Parus major) in high knotweed cover and negative effect of Grey Wagtail (Motacilla cinerea). Interspecific comparison common avian characteristics suggest that knotweed invasion can impact avian abundance living in lower...
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Homogenization of bird communities
Krsová, Magdalena ; Reif, Jiří (advisor) ; Sedláček, Ondřej (referee)
Biotic homogenization is characterized as a process by which means species invasions and extinctions increase the genetic, taxonomic or functional similarity among ecological communities and this process is associated with modern biodiversity crisis. The most prominent patterns of recent homogenization of species composition in avian communities are loss of native species and their replacement by non-native species, expanding habitat generalists at the expense of native and more specialized species. As a result, increases in local or alpha-diversity typically occur at the expense of decreased beta-diversity or increased community similarity among regions. These patterns are probably caused by introduction non-native species, urbanization, landscape fragmentation and disturbance. These results suggest that conservation effort should focus on protection of unique habitats where ecologically specialised species occur. Further research in this area could provide better basis for generation of simulation models aimed to predicting changes in community composition.
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The role of ultraviolet light in communication of birds
Šulc, Michal ; Sedláček, Ondřej (advisor) ; Albrecht, Tomáš (referee)
Recently, it has been found that the visual system of birds and humans differ remarkably, especially in the ability to perceive ultraviolet radiation. This component of the spectrum significantly affects various types of the birds' behaviour. UV reflection may be an indicator of the qualities of males, i.e. females often prefer individuals with expressive UV ornamentation. Likewise, parents can distribute the delivered food unevenly among their nestlings, depending on the nestlings' reflection of ultraviolet radiation. Recent studies also showed that the hosts of brood parasites may use UV spectrum as a key for recognizing the parasitic eggs from their own. The aim of my bachelor thesis is to review the current knowledge of the influence of UV radiation on sexual selection of birds, the interaction between parents and offspring and interactions between brood parasites and their hosts.
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The Use of Insects for Monitoring Global Changes
Ali, Mohamed Abdussalam ; Jarošík, Vojtěch (advisor) ; Frouz, Jan (referee) ; Sedláček, Ondřej (referee)
Abstracts ofthe stuďes inc|uded |n the thesir Effect ofland useandclimate on ďversity ofmoth guilds with differenthabitatspecialization MoEAli'EDAL| ADDUSSALÁMM. KoTELA', ToMÁŠ K.lolrcl, Ivo NovÁr2, Mmrnl Korwrčxl3'a lNo VorÉcrr JlnoŠkL5 LDepartmentofEcologt, Factlty ofScience,Charla ^ Univqsiý,Prague,CzechReptblic, .ResearchInstituteofCrop Proúaio4 Prague 6-Ruzyně,the - CzechRepublic 'InstituteofEntomologl, AcademyofSciences oÍtheCzech Republb' CeskzBudejovžce'CzechRepublic aSchool ofBiologiml Sciences,Universityof Southen - Bohemia,CeskeBudejoice, CzechRepublic 'Institute oÍBotany,AcademyofScienca ofthe Czech Republic,Průhonice,CzechRepublic Address for corr$pondence: Vojtěch JarošflqD€paÍtment of Ecolory' Faculý of Sciences,ChaÍlesUniversiý, Viničná Abstrecí An assemblageofmoth speciesata suburbof Prague(5005'11'\l4ol8'06"E) wasnonitoredby a highly efficient mercurylight trapfor 23 years(1967-1976,l98O- 1992).Speciescaughtrťeíedividedinto sevenguilds accolding to habitatspecialisation,andanďysed for yearly catchesandeffectofannual meant€mperatuÍeatrd precipitatiouby shannon's indexofdiversiý' separatelyfor ďl andabundant(z 5 individuals per yea) species.overal| 424 specieswasrecorded:25 early successionalspeciesof arableland (43%of all caughtinďviduals), 116 forestspecies feedingon...
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Links between nest positions and intraanual dynamics of Blackcaps’ territories.
Vojtěchovská, Eva ; Šizling, Arnošt Leoš (advisor) ; Sedláček, Ondřej (referee)
This diploma theses intention is to study territory dynamics and it's relationship to parameters of territories, position of nest and reproductive success of blackcap (Sylvia atricapilla). I assumed, that parameters of territories are depended on breeding phases and on intraspecific interaction with neighbours and conversely, that position of nest is depended on the territory parameters. The research of territory dynamics was performed in a nature preserve Lipovka (14,6 ha) in breeding seasons of years 2006 and 2007. Main method of the research was mapping territories of blackcaps, based on registrations of colour-marked males (territory owners) and finding and observation of nests. On all found nests we noted their position on the locality, progress of breeding, breeding size and success and nest concealment. During two breeding seasons we catched and colour-marked 58 individuals. In 2006 we mapped 25 pairs of blackcaps, which were breeding and we found 30 nests of which 13 were successful. In 2007 22 pairs were breeding and we found 33 nests of which 14 were successful. Results have shown, that male territory parameters are influenced by passing breeding phase. So, male's territory, is greatest in before and after breeding phases, whereas the size significantly decreases through egg phase to nestling...
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