National Repository of Grey Literature 22 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Jeřábková, Lenka ; Švátora, Miroslav (advisor) ; Rehák, Ivan (referee)
8 ABSTRACT In the north-east part of the Třebíč district 108 water sites were repeatedly monitored to analyze breeding of amphibians where its 11 species were proven by this research. Bombina bombina, Bufo bufo, Bufo viridis, Hyla arborea, Pelobates fuscus were proven in line with previous studies. However, species Triturus cristatus, Triturus vulgaris, Rana temporaria, Rana dalmatina, Rana esculenta synklepton were monitored in the region for the first time ever. Distinctly high values of the species presence were reached by BufBuf (60,2 %), RanEscSyn (78,7 %) and HylArb (48,1 %). In contrast, species TriCri, TriVul, BufVir, RanArv, RanDal were found in the region with low frequency. There were found positive correlations in the proportion of littoral, natant and submerse vegetation and in the transparency of the water column and in contrast negative correlations were found in the extent of urban areas and with the number of amphibians breeding in the water site. The Redundancy analysis (RDA) helped to discover statistically significant influence of the environmental variables (proportion of littoral vegetation, transparency, water site total surface and lastly number of other water sites within the range of 500 metres) on the presence of amphibians on the water sites. Consequently, "ideal breeding sites"...
Development of endemic freshwater ichthyofauna of Greece
Kyralová, Eva ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
The Balkans is one of the hot spots of biodiversity, and is known for a high diversity and endemism of freshwater fishes. The development of Greece was significantly affected by the climatic, geologic and orogenetic events resulting in high concentration of freshwater fish endemism. Some of the important historical events were the emergence of land bridges during the early Oligocene and Miocene, through which freshwater fishes dispersed to the Balkans from Asia and subsequently to Africa, the freshwater phase of the Paratethys sea or Alpine orogeny, which began 65 million years ago, and which gradually formed the Greek mountain systems, leading to a long-term isolation of local freshwater ichthyofauna and subsequent speciation. Other major events include Messinian salinity crisis and Pleistocene climate oscillations. Most of the freshwater fish families occurring in Greece most probably originated in the Southeast Asia, from where they colonized the Balkans by several routes. These colonizations took place repeatedly at different times and by different routes. The dispersion of freshwater fishes from Asia to Europe through Siberia started before the uplift of the Ural Mountains about 33 million years ago and continued until Pliocene. Another important colonization route from Asia was via the...
Genetic variability of the genus Alburnoides in Azerbaijan
Omelchenko, Dmytro ; Švátora, Miroslav (advisor) ; Vukićová, Jasna (referee)
The Caucasus region is characterized by high rate of endemism and taxa richness of fishes. Azerbaijan is a country situated on the border between Europe and Asia with rivers flowing in the Caspian Sea. Natural environment of this country is represented by various habitats with diverse ichthyofauna. This region is very attractive for biogeographical studies because it lays on the border of two different ecoregions. Even on the modern stage of scientific cognition, there is still lack of data about freshwater fishes from that region. Spirlins or rifle-minnows (Alburnoides Jeitteles, 1861, Actinopterygii, Cyprinidae) is a genus of small freshwater fishes and it has been chosen as a focus of this thesis because of numerous reports of new species from surrounding countries. The presented thesis is one of the seldom molecular studies trying to reveal the taxonomical situation within the genus Alburnoides, describe the phylogenetic relationships between geographically isolated populations, and provide biogeographical implications for fishes in the Caspian Sea river basins. Both mitochondrial (cytochrome b, cytochrome oxidase subunit I) and nuclear (RAG1, rhodopsin) markers were used in the study and the Maximum Likelihood, Maximum Parsimony and Bayesian phylogenetic analyses were performed. Further, the...
Non-indigenous freshwater fish species of the Mediterranean basin of the Balkans
Balog, Štefan ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
Mediterranean basin of the Balkan Peninsula is one of the hot-spots of biodiversity, with a high diversity of freshwater fishes and high degree of endemism. Introduction of non-native species greatly affects ecosystems and native species of fish. There were many reasons for introductions in the past. Aquaculture, sport fishing and ornamental fish belong to the most important reasons for introduction of non-native fish species. Altogether, 39 species belonging to 12 families were introduced in the Mediterranean basin of the Balkan Peninsula. Most of them belong to the families Cyprinidae and Salmonidae. Introduction of fishes was known since the Roman era. Although the first recorded introduction in this area was in the 13th century, most species were introduced in 20th century. The fishes were introduced from North America, Europe and Asia. Many translocations occurred in this area, too. Translocation is a relocation of particular species within one area. The most widespread introduced species in the Mediterranean basin of the Balkans are common carp (Cyprinus carpio), stone moroko (Pseudorasbora parva), rainbow trout (Onchorhynchus mykiss), mosquitofish (Gambusia holbrooki), goldfish (Carassius auratus) and sunfish (Lepomis gibbosus). Hybridization, competition, pathogen transmission and predation...
Methods of study habitats and microhabitats preferences of freshwater fishes of Central Europe
Žák, Jakub ; Švátora, Miroslav (advisor) ; Drozd, Bořek (referee)
Small streams are a common habitat in Central Europe with unstable, rapidly-changing conditions. We can examine habitats on three different scales: microhabitat, mesohabitat and macrohabitat. Habitat preferences were among the fields of interest of Antonín Frič as he tried to describe the changing gradient of fish assemblages from source to the river's mouth on the macrohabitat scale. Habitat preferences are examined from a spatial point of view (substrate, depth, shelter), temporal point of view (season, day/night), biotic point of view (interspecies and intraspecies competition) and abiotic point of view (dissolved chemicals, velocity). For obtaining data of good quality, it is necessary to choose the right location and select the opti- mal strategy of examining fish assemblages (e.g. electrofishing, radiotelemetry, cameras). All variables which can affect habitat preferences in fish are measured. Multivariate statistical methods (e.g. PCA, RDA, CCA, CA) are used for evaluation of obtained datasets. Currently, we live in a fast developing period of this scientific area because of the need of evaluation of the human impact on freshwater biotope. The aim of this bachelor thesis is to introduce variables which influence habitat pref- erences of fish, to propose a modern review of methods commonly...
Population dynamics of Asp Leuciscus aspius from the Želivka dam
Bouše, Eduard ; Švátora, Miroslav (advisor) ; Pivnička, Karel (referee)
The aim of this study was to evaluate the material about the asp Leuciscus aspius (L., 1758) from the dam Želivka - Švihov in the years 1971 - 2014. Main emphasis was put on the analysis of the flock spawning from 2008 - 2014. Here, basic abiotic conditions were monitored at the time of the spawning and growth and population characteristics were calculated. Spawning took place at two locations, at 4 - 10 0 C, the asp showed a spawning site accuracy. Males predominated on the spawning grounds in the overall ratio of 1,22 : 1. The age of the fish examined ranged from 3+ to 13+. The average mortality of adults is about 0,4. Additional flock spawning ranges from 20 to 50%. The length at which scales begin to form (SL = 29,7 mm), was determined by using the rate between the body length and scale radius. Differences in the growth rates between males a females are minimal, only from the third to the fifth age group, males showed a higher growth rates. The length - weight relationship can be described as W = 0,0153. L3,19 .

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1 Švátora, Milan
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