National Repository of Grey Literature 26 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Environmental influences on the shape of ultraviolet signals in genus Gonepteryx (Lepidoptera, Pieridae).
Pecháček, Pavel ; Kleisner, Karel (advisor) ; Zapletalová, Lenka (referee) ; Vrabec, Vladimír (referee)
Like many other animals, butterflies are able to visually perceive the ultraviolet (UV) light; many species even have patterns on their wings which are visible in this part of the electromagnetic spectrum. Over the last forty years, it has been shown that these UV patterns play an important role in behaviour of many butterflies, especially in relation to sexual selection - they are involved in the process of recognising a suitable mate, and likely can signal some of the mate's qualities, such as its age, ability to handle stressful environmental factors, or efficiency in foraging. The patterns may also be used for taxonomical purposes. This dissertation thesis contains a comprehensive research into ultraviolet patterns of the Gonepteryx brimstones, with a primary focus on the issue of environmental influences in relation to the expression of these traits, on the patterns' potential role in sexual selection, or on their evolution. It has been successfully demonstrated that UV patterns of at least some Gonepteryx species are affected by the environment to a strong degree, significantly more than the traits not involved in sexual selection. On the whole, the conclusions made by submitted publications suggest that UV patterns play a role in the sexual selection of the chosen brimstones, though it is not clear...
Environmental influences on the shape of ultraviolet signals in genus Gonepteryx (Lepidoptera, Pieridae).
Pecháček, Pavel ; Kleisner, Karel (advisor) ; Zapletalová, Lenka (referee) ; Vrabec, Vladimír (referee)
Like many other animals, butterflies are able to visually perceive the ultraviolet (UV) light; many species even have patterns on their wings which are visible in this part of the electromagnetic spectrum. Over the last forty years, it has been shown that these UV patterns play an important role in behaviour of many butterflies, especially in relation to sexual selection - they are involved in the process of recognising a suitable mate, and likely can signal some of the mate's qualities, such as its age, ability to handle stressful environmental factors, or efficiency in foraging. The patterns may also be used for taxonomical purposes. This dissertation thesis contains a comprehensive research into ultraviolet patterns of the Gonepteryx brimstones, with a primary focus on the issue of environmental influences in relation to the expression of these traits, on the patterns' potential role in sexual selection, or on their evolution. It has been successfully demonstrated that UV patterns of at least some Gonepteryx species are affected by the environment to a strong degree, significantly more than the traits not involved in sexual selection. On the whole, the conclusions made by submitted publications suggest that UV patterns play a role in the sexual selection of the chosen brimstones, though it is not clear...
Comparison of population parameters of Large blues from genus Phengaris on multiannual basis
Bártů, Nikola ; Vrabec, Vladimír (advisor) ; Petr, Petr (referee)
There where evaluated the changes in abundance of overall metapopulations and abundace of butterflies on surveyed areas occupied by Phengaris nausithous (Lepidoptera: Lycaenidae). It ran on two long-term monitored locations in the Czech Republic : Slavíkovy ostrovy u Přelouče a Dolní Labe u Děčína. Data for this comparison was obtained by longterm monitoring of the abundance of butterflies on these locations. The method of reverse capture of labeled specimens was used and then statisticall processing of marking results in program MARK. In final number of the target species has been found significant fluctuation , after our evaluation. Abudance of total metapopulation in Přelouč in years from 2004 till 2016is variable from 148 up to 1 369 butterflies, numbers in Děčín between 2008 and 2016 has vacillated from 273 to 1952 individuals. Growth of abudance of metapopulation on these two locations are obvious from crossing both diagrams (in years 2006, 2010-11 and 2014-2015). However, observing time-lime is not so long, this is very strong argument to support this hypothesis: ,,From aged time sequence there is noticable graduation periodicity. Than has been compared progression of population of individual locations compare to metapopulation of both locations together and it has discovered this observation is a real picture of aged progress. Most of places of research copying trend of metapopulation. If there are any differences, for example total metapopulation grows, but population of individual location declines, it could be explain as a change of familiar location related on mamagement, in this case on the wrong one. Contrariwise, rising of individual colony against the trend of metapopulation, mostly shows a positive changes in maintenance of site. Long therm researching is highly recommented for rating of impact of management.
The status of Phengaris nausithous population on selected meadows in Broumovsko region
Štěpánková, Anežka ; Vrabec, Vladimír (advisor) ; Kamil, Kamil (referee)
The purpose of this thesis entitled Population Status checkered blue butterfly Phengaris nausithous (Bergsträsser, 1779) on selected meadows in Broumov area was to find and evaluate the situation regarding the size and structure of populations of the butterfly Phengaris nausithous, on a recently selected location within the territory of the Czech Republic. A used monitoring method was a Capture-Recapture method at 13 locations in the PLA Broumovsko, where the occurrence of the food plant Sanguisorba officinalis, which is an integral part of the species evolution, was the key for choosing the location. The ant of the genus Myrmica is also important for the evolution of the P. nausithous. The results were evaluated using the program MARK and Statistika and then transferred into graphs and tables. In 2016 it was marked 687 of the P. nausithous and the sum for the overall metapopulation totaled 1,487 individuals. Most of the P. nausithous occurence with the number of (fixed catches) 149 was registered at the Hynčice 2 (H2) area, which was the third largest area of all studied habitats. The least number of 15 of the P. nausithous has been marked at the Hynčice 1 (H1) area. Maximum estimates of numbersfor patches were determined with the program MARK with the highest number of 367 individuals in the H2 area, whereas the lowest number of 38 individuals at the H1 area.The numbers of P. nausithous determined by the application MARK were significantly higher than those of fixed catches, indicating good aplication of methodology. It was captured a total of 49 migrations. Overall 31 % of individuals migrated and 18 % of individuals migrated within assumed total number. Most flyovers were between the areas H2 and H4 (11 flyovers) and between areas V1 and H4 was recorded flyover at a distance of 5.3 km, which can be considered as one of the longest flyovers. The average distance of migration of P. nausithous was 1.46 km. The number of immigrants for solid flyovers was set to 49 individuals and the number of immigrants to 58 individuals. The hypothesis of this work was: All the examined areas communicates using flyovers of butterflies and the system can be considered as a single metapopulation and was confirmed given on the basis of the results. Target species dependence on the density of host plant vegetation was not crucial according to the graphic representation. The first T-test found that there is no association between P. nausithous abundance and between the length of the migration between particular areas. The second T-test found that with increasing number of flyovers the length of those flyovers gradually decreased.
The status of Large Blue Phengaris teleius population on selected meadows in Broumovsko region
Hejretová, Kateřina ; Vrabec, Vladimír (advisor) ; Kamil, Kamil (referee)
I conducted a monitoring of Scarce large blue Phengaris teleius (Bergsträsser, 1779) by reverse capture of marked individuals method on 13 examined meadows in Broumov area near Ruprechtice, Hyncice and Vižňov in the period from 4th July to 5th August of 2016. I marked a total of 409 butterflies of this species. Data were evaluated with the help of software MARK 8.1 and the total number of butterflies metapopulation was estimated at 802 individuals, whereas the estimates of quantity for each area ranged from 2-269 specimen. I registered most of the individuals at the Ruprechtice 2 station. I documented the flyovers of P. teleius individuals between stations within a Ruprechtice Hynčice area. I consider the involvement of Vižňov as realistic, but due to the local total number of butterflies, the detection of P. teleius flyover failed. I consider the hypothesis formulated in the objectives of the work: All the examined areas communicates via overflights of the butterflies and the system can be considered as a single metapopulation, as confirmed. I consider as important a finding that there still lives a stable population of Phengaris teleius and P. nausithous butterflies in Broumov area. The numbers of these butterfiles are in hundreds to thousands of individuals, and it is important to remember that this is only the population of examined areas, not all areas of occurrence of blue butterflies in stated territories. Those numbers after the first year of observation are unknown. The layout of examined colonies is beneficial for targeted protection planning. The metapopulation model continent islands is not the case of stations examined by myself.
Comparison of water beetles fauna between forefield and reclamation of the landscape affected by mining
Vostalová, Adéla ; Vrabec, Vladimír (advisor) ; Josef, Josef (referee)
The issue of redress anthropogenic interference with the landscape is one of the discussed topics today not only in professional groups but also among the public, because mineral mining takes place in many places in the Czech Republic. More and more are beginning to promote nearnatural methods of renewal at the expense of recently prevalent technical reclamation. Except for question, how the exhausted places reuse or renew also researches, how the whole process has an impact on the local fauna and flora. The aim of this thesis was a qualitative comparison of water beetles among the forefield Bílina Mine and reclamation dumps Radovesice and Pokrok in North Bohemia province. It was evaluated 16 reservoirs in forefield and 15 reservois of dumps. A total of 36 taxa were found from which 19 were determined only at the species level. The most of taxa were located at post R9 in the forefield, at 4 locations there were none of them. The most abundant was genus Haliplus. The collection took place using standard hydrobiological sampling by sieve. The material was preserved in alcohol, then separated, prepared and finally determined. The obtained data were evaluated and compared using the Jaccards index of similarity. It was tested hypothesis: Due to the good dispersion ability of water beetle is representation of species in the forefield the same as constitution of species in the newly ponds at reclamations. Calculation Jaccard index between locations of forefield and dump reached the highest value of similarity 66,7 %, but over of the value 50% moved only in 7 cases out of 465 possible combinations, thereby hypothesis was disproved. Found species were also evaluated from point of view conservation status according to the Red list of threatened species in the Czech Republic. This way was detected only one species, Laccophilus poecilus, falling into the category VU vulnerable. The determination must be examined.
Comparison of mollusc fauna from selected natural reserves on southern Moravia
Bohatá, Lucie ; Vrabec, Vladimír (advisor) ; Jan, Jan (referee)
In this thesis is compared mollusc fauna of six protected areas on the south of Moravia, with characteristic and appraisal of their condition. These protected areas belong to control of BR Lower Moravia and almost all of them belong under control of CHKO Pálava: NPR Cahnov Soutok, NPR Křivé jezero, NPP Pastvisko u Lednice, NPR Ranšpurk, NPR Slanisko u Nesytu, EVL Trkmanské louky. Tested hypothesis was, whether reserves with prevailing of forest cover evince richer faun compare to reserves with prevailing of open space. Mollusc fauna was collected by individual picking with the aid of flush solid material through strainer and off take of forest soil. Subsequently collected material was inspected in detail, sorted out and determined. Information about discovered species was compared with the aid of Simpson´s index of domination and Jaccard´s index of similarity and recorded to tables. The biggest index of diversity has NPR Ranšpurk and the lowest has NPR Slanisko u Nesytu according to Simpson´s index. It means that community of molluscs from NPR Ranšpurk is covered same amount of specimen determined species, while on NPR Slanisko u Nesytu was discovered dominance of vulnerable species Anius spirobis (Linné, 1758). According to Jaccard´s index of similarity is the most similar (31%) reserve NPR Křivé jezero and NPR Slanisko u Nesytu and the worst similar (8%) are reserves NPP Pastvisko u Lednice and EVL Trkmanské louky. Hypothesis was confirmed on the grounds of number of species determined on collected stations and Simpson´s index with bigger diversity on reserves with prevailing of forest cover. According to Jaccard´s index of similarity are forest areas and open areas similar with 66%. The high similarity is consequence of abiotic factors, which influence inspected areas in reserves.
Overview Copulation Strategies of European Butterflies
Baráková, Kristýna ; Vrabec, Vladimír (advisor) ; Bubová, Terezie (referee)
Daily butterflies are a very varied and diverse group of the animal kingdom. They are insects with complete metamorphosis and a complex life cycle. Different stages of the development cycle are well known and studied. However, when it comes to the reproduction biology of daily butterflies, there are still a lot of question marks. This is why we decided to compile available information on reproduction strategies of European daily butterflies. This information was gathered by the means of strategically chosen keywords in scientific databases Web of Science (WOS), Scopus and Google Scholar. Based on these sources I compiled general information on reproduction behaviour of butterflies related to the complex processes before copulation, more concretely the mating and selection behaviour of daily butterflies. Consequently I describe concretely the copulation process, where I concentrate mainly on data on the progression of copulation, i.e. duration, minimum age or possible repeated copulation. I also explain general terms connected to copulation, such as paternity or protandry. The following part of the thesis concentrates specifically on copulation strategies of European daily butterflies. For the majority of butterflies I gathered data on mating strategies before copulation, specifically on how males search for females. Furthermore, for som e butterflies I add comprehensive data on duration of copulation, minimum age for copulation or possible repeated copulation. However, the gathered data do not provide sufficient information on the stated topic. It was therefore impossible to realize a statistical evaluation, which was supposed to lead to a recount against the total number of European butterflies. The hypothesis, namely that the vast majority of daily butterflies does not show promiscuous behaviour and copulates only once, has not been affirmed, neither disproven. Scientific publications only scarcely provided concrete information on promiscuous behaviour of daily butterflies. A research on this behaviour would require a more thorough examination. But it would enable us to organize accessible data on butterflies in the Czech Republic.
Owerview of snakes using strangulation to kill prey
Jeřábková, Adriana ; Vrabec, Vladimír (advisor) ; Killerová, Šárka (referee)
Purpose of studies was collecting list of snakes - constrictors. There were suggested two hypothesis; 1st - killing prey using strangling is mostly widen by large snakes than smaller ones. 2nd; Mechanism going while grabing and following killing of prey were in different kinds of snakes constrictors generated convergently and are similar. From given list of kinds of snakes and figures telling their proportions it is obvious that strangling as form of killing is major by snakes over 1,5m, therefore first hypothesis I can confirm so. Also from table of expansion individual genuses using strangling it is apparent that this method killing is known in all continents where snakes lives and simultaneously with fylogeneticaly receded kinds of snakes. I can then with higher probability confirm also second assumed hypothesis, nevertheless, own grabing and killing strategy of prey is different in some details. Some kinds challenge prey from ground, possibly from water, some kinds attack prey from trees and bushes. Difference in rotation of body along prey warries by grass snakes and by boid snakes. Boids bend neck verticaly around prey, while many grass snakes bend body sideways around the prey. It was made many tests of measuring strenght and mechanism strangling by various methods, e.g. Magnetic Resonance, Autopsy etc., however these experiments cannot be classified to this work for reasons of great amount given experiments and great amount of outcomes.
Caterpillars food of Minois dryas on selected area
Hájková Březinová, Kateřina ; Vrabec, Vladimír (advisor) ; Kamil, Kamil (referee)
The dryad Minois dryas, described in 1763 by Giovanni Antonio Scopoli, belogs to our endangered species of butterflies. Its expansion today is restricted to a few localities in Central and Southern Bohemia and Southern Moravia only. Renewal and preservation of appropriate types of biotopes and research of its autecology and bionomy play the key roles in conservation of this species. The intention of my thesis was to identify host plants of Minois dryas caterpillars, to find out which grass is the most preferred one and to verify the correctness of hypothesis that the most preferred plant is also dominant from the range of potential host plants in the chosen area (a meadow in the vicinity of Žehuň in Central Bohemia). In the first part of experiment caterpillars were offered grasses collected in Žehuň. Plants which were eaten by caterpillars, were determined as host plants. According to results of this stage the host plants of caterpillars in the Czech republic are Dactylis glomerata, Bromus erectus, Festuca rubra, Arrhenatherum elatius and Carex acutiformis. In the second part of experiment caterpillars were offered all grasses evaluated in the first part as host plants and frequency of eaten / untouched leaves was recorded. Results identified Bromus erectus as the most desired grass and statistical proved there was a strong dependance among the plants . As Bromus erectus is indeed the most dominant grass in the location (approx. 30 % of all grasses), the hypothesis was confirmed. The experiment contributed with some other knowledge about dryad's bionomy. Observations confirmed that caterpillars pupate at the turn of June and July, primarilly at night. Larvae pupates in or on the ground. I did not notice any silk spinning during the time of pupation which is mentioned by Beneš et al. (2002). The pupal stage lasted 22 -- 23 days. Butterflies hatched in the morning. Imagos chose red watermelon as a food in most cases which proves that adults prefer red colour while deciding on their food (Vrabec et al., 2007).

National Repository of Grey Literature : 26 records found   1 - 10nextend  jump to record:
See also: similar author names
1 Vrabec, V.
2 Vrabec, Vojtěch
2 Vrabec, Václav
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