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Selekce potravy bobrem evropským (Castor fiber) v hospodářských porostech jižní Moravy
Černíková, Karla
The bachelor's thesis deals with the selection of food of European beaver (Castor fiber) in the Tvrdonicko area, specifically in the surrounding stands of six blind branches of the Morava River. Czech and foreign literary sources served as the basis for the literary part of the work. For the practical part of the work, data from the field survey, which took place in the winter period of 2017 and 2018, were used. The most preferred tree species in this area were poplar (Populus sp.), babyka maple (Acer campestre), willow (Salix sp.), ash (Fraxinus sp.) and blackthorn (Prunus spinosa). The beaver preferred the most young stands with individuals of smaller diameters. The damage to the vegetation was very low compared to other localities. The results of this work mostly confirm the information presented so far on the selection of woody plants by a beaver. It also focuses on evaluating the factors that influence food choices.
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Surviving of Northern Lapwing (Vanellus vanellus) chicks in agriculture landscape
Kubelka, Vojtěch ; Šálek, Miroslav (advisor) ; Cepák, Jaroslav (referee)
The variability of egg-size within a bird species reflects different reproductive investments and, besides the intrinsic constraints and particular female quality, it can be affected by environmental factors, too. Moreover, the egg-size predetermines the chick performance. The knowledge of factors influencing precocial chick survival is crucial for better understanding of life-history strategies as well as for endangered species conservation. The Northern Lapwing (Vanellus vanellus) represents a suitable model species for investigation of climate variables effects on egg-size and also to study factors influencing chick survival. Eggs in a total of 714 nests were measured during 13 breeding seasons over period 1988-2014 in South Bohemia and 293 lapwing chicks from 100 broods in 37 localities were monitored in 2013-2014. The mean egg-size through the whole season is positively affected by March precipitation, March clutches also negatively by minus temperatures in March. The higher intensity of rainfall there is during March, the bigger eggs are laid in March and the steeper is slope of decline in mean egg-size during season. This decline is more profound with lower rainfall in April. The effect of habitat is not significant. The body mass and condition of hatchlings is positively correlated with the...
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Habitatové preference skorce vodního (\kur{Cinclus cinclus}) na tocích okresu Tachov.
LIŠKA, Martin
In the first part of the thesis, the number of breeding pairs of the White-throated Dipper on the watercourses of Tachov district in western Bohemia was monitored and their distribution was examined. In the second part, characteristics (chemical, physical, geographical, quantity and quality of prey) of occupied territories and reference plots were examined and the preferences of the Dipper were examined. In the third part, correlations between body characteristics of birds and quantity of prey in the territory were examined.
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Surviving of Northern Lapwing (Vanellus vanellus) chicks in agriculture landscape
Kubelka, Vojtěch ; Šálek, Miroslav (advisor) ; Cepák, Jaroslav (referee)
The variability of egg-size within a bird species reflects different reproductive investments and, besides the intrinsic constraints and particular female quality, it can be affected by environmental factors, too. Moreover, the egg-size predetermines the chick performance. The knowledge of factors influencing precocial chick survival is crucial for better understanding of life-history strategies as well as for endangered species conservation. The Northern Lapwing (Vanellus vanellus) represents a suitable model species for investigation of climate variables effects on egg-size and also to study factors influencing chick survival. Eggs in a total of 714 nests were measured during 13 breeding seasons over period 1988-2014 in South Bohemia and 293 lapwing chicks from 100 broods in 37 localities were monitored in 2013-2014. The mean egg-size through the whole season is positively affected by March precipitation, March clutches also negatively by minus temperatures in March. The higher intensity of rainfall there is during March, the bigger eggs are laid in March and the steeper is slope of decline in mean egg-size during season. This decline is more profound with lower rainfall in April. The effect of habitat is not significant. The body mass and condition of hatchlings is positively correlated with the...
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Species diversity and abundance of small terrestrial mammals in several types of forest stands in Třeboňsko study area
Dvořák, Jiří ; Kouba, Marek (advisor) ; Šťastný, Karel (referee)
The goal of this thesis was to find the diversity and abundance of small mammals in several types of forest and non-forest ecosystems in the protected landscape area of CHKO Třeboňsko. Further, the goal was to compare the collected data with analogical data from Krušné hory and finally discuss the findings in relation to the abundance of the Tengmalm´s Owl (Aegolius funereus) in both areas.
Trapping by collapsible snap-traps was practiced in both of the abovementioned protected landscape areas. In case of Třeboňsko, six spring and six fall quadrants were established, while the area of one quadrant was designated to 270 m2with 40 traps laid. In contrast, the small mammals in Krušné hory were being caught on three spring and three fall quadrants. The area of one quadrant was designated to be 1 ha with each quadrant containing 121 laid traps. The result numbers of caught individuals were converted into the number of trapped individuals per 100 trap nights. The number of nesting pairs of Tengmalm´s Owl was established by regular visits of hanging nestboxes in both of the protected landscape areas.
In 2014, 42 individuals were caught in Třeboňsko. The following species were recorded: yellow-neck mouse (Apodemus flavicollis), bank vole (Clethrionomys glareolus), and common vole (Microtus arvalis). For this year, the highest diversity of species was recorded in localities "pine north" and "open area south". The highest number of individuals caught (21) was in the quadrant of "pine north".
The year 2015 was more colorful in case of recorded species, however the total number of caught individuals was only insignificantly higher (49 individuals in total). The following species were caught: yellow-neck mouse, wood mouse, bank vole, common shrew (Sorex araneus), and field vole (Microtus agrestis). The highest species diversity was recorded in the quadrant of "spruces north" and the highest number of caught pieces (24) was recorded in the quadrant of "pine north".
In case of Krušné hory, there were 31 caught individuals in 2014 and 193 individuals in 2015. The species diversity of small mammals was equivalent as in the experimental localities in Třeboňsko, additionally, only the eurasian pygmy shrew (Sorex minutus) was recorded.
The following numbers of nesting pairs of Tengmalm´s Owl were recorded through the regular visits of nesting boxes: in the year 2014, there was not a single nesting pair in the area of Třeboňsko; in the year 2015, there were 3 nesting pair. In Krušné hory, for the year 2014, there were 10 nesting pair recorded, and for the year 2015, 34 pair were recorded.
Even though the food supply was similar, there was a significant difference in the numbers of nesting couples in Třeboňsko and Krušné hory. It seems probably, that the Tengmalm´s Owl simply prefers natural nesting cavities over the hanging booths in Třeboňsko.
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The feeding biology and growth of European weather loach (Misgurnus fossilis)in the first year
KOCIÁN, Pavel
The principal aim of this bachelor thesis is to describe the feeding biology and growth of European weather loach (Misgurnus fossilis). In Introduction, the overview of literary sources is presented and existing publications are documented. The main part of this thesis concerns the experiment itself, based on which the feeding biology and growth of European weather loach in the first year of its life is discussed, with primary accent on food determination and food supply description. In final section, the results of food preference and running growth of fish in various periods of reduction fishing are presented. The results have shown that in the first month, fish feeds dominantly on daphnias, rotifers and testaceas. In the beginning of the following period, the fastest growth of all individuals was observed and fingerling started to prefer water fleas, ostracods and chironomids larvae.
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Study of selected factors influencing the nesting population of reed warbler (Acrocephalus scirpaceus)
KITTLOVÁ, Lucie
The aim of this work was to study the occurrence, abundance and distribution of breeding population of model species Reed Warbler (Acrocephalus scirpaceus) at selected locations. Subsequent evaluation is based on the monitored nesting parameters: nest height above water surface, water depth, distance of the nest from unvegetated water surface, the distance of the nest from the nearest fixed point, and number of stalks on which the nest was built. Diet spectrum was also detected. The results were statistically analysed in order to find out if and how these factors could influence nesting success and density of Reed Warbler population. Marginal influence on nesting success was found out only in these parameters: the number of stalks (the nests with three stalks was the most successful) and the distance from the fixed point. Successful nests were about 26% further (1.8 m) than the unsuccessful nests that could be explained by the predator factor. The most numerous insect orders in selected locations were Diptera (60%), Hymenoptera (21%) and Araneae (12%).
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