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Effect of alarm call on tits' behavior on feeder
Lipanská, Barbora ; Fuchs, Roman (advisor) ; Petrusková, Tereza (referee)
LIPANSKÁ, B. 2011: Effect of alarm calls on tit's behavior on feeder. MSc Thesis. Faculty of Science, Charles University in Prague. Alarm calls of the Great tit (Parus major) used in the context of ground-predators or perching-raptors consist of high-frequency tonal syllables and of series of churring syllables with broad-frequency range. The function of some acoustical parametres of these complex calls was tested in playback experiment on feeder. As the most effective appeared to be alarm calling of two birds simultaneously. More important for warning function of the calls were broad-frequency range syllables. The length of series of these syllables had an opposite impact than in some north-American chickadees (genus Poecile). The Blue tit (Cyanistes caeruleus) responds to Great tit's alarm calls, but its reactions are weaker. This difference can be caused by its lower competition ability against the Great tit. Key words: antipredation behavior, alarm calls, tits, playback experiment
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The effect of a predator occurrence on vigilance of tits visiting the winter feeder
Tichá, Irena ; Fuchs, Roman (advisor) ; Sedláček, Ondřej (referee)
This thesis evaluates the vigilance parameters of two species of tits affected by the presence of a predator in wintertime. During preferential experiments, tits have had a choice of two feeders in the vicinity of the installed dummy predator. For that purpose was used a dummy sparrowhawk, incomplete or occluded sparrowhawk torsos, and harmless pigeon. It is known that the tits are able to recognize dangerousness presented by the dummy, and according to expected risk dare to visit one of the feeders. It leads to a question whether the tits are somehow influenced by the presence of the dummies, and if so, how specifically are they influenced. It turned out, that the tits in presence of a dangerous dummy significantly increased their vigilance. Both observed species at the feeders behave oppositely. Behaviour of all the birds at the feeder is also affected by their total count at the precise moment and by the presence of a dummy at the other feeder.
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Male quality, extrapair paternity and parental investments in scarlet rosefinches
Schnitzer, Jan ; Albrecht, Tomáš (advisor) ; Fuchs, Roman (referee) ; Šálek, Miroslav (referee)
Social monogamy, closely associated with bi-parental care, is the most frequent pairing system found in birds. Because females invest more into the reproduction, they are usually considered to be the sex that chooses the partner. To satisfy female preferences in the mate choice males in various species developed a number of traits that signalize their quality. What qualities are signaled by these traits and what mechanisms are responsible for the emergence, development and maintenance of these traits is the subject of a number of evolutionary- ecological studies. By pairing with an appropriate male female can obtain direct or indirect benefits to its own fitness. The good parent theory suggests that male secondary sexual traits signalize male ability to provide parental care (a direct benefit). An indirect benefit is presented by the quality of the genetic material that the female obtains from male for her offspring. According to the good genes hypothesis females use secondary male ornamentation to assess genetic quality of males. One of the most studied secondary sexual ornaments that can advertise male quality and may be used in mate choice by females is the plumage colouration. In many avian species there is sexual dimorphism in the plumage colouration and there is also growing evidence that...
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The use of amodal completion inpredators recognition: effect on risk taking
Sedláčková, Kristýna ; Fuchs, Roman (advisor) ; Nekovářová, Tereza (referee)
Amodal completion enables animals (birds, mammals, but also fish) to perceive partly occluded objects as whole. Most of the studies focusing on the occlusion phenomenon were carried out in a laboratory and were based on either operant conditioning or filial imprinting techniques. This study concentrates on behavior of untrained animals in their natural habitat. Pairwise preferential experiments were used to reveal responses of tits (the great tit, Parus major; the blue tit, Cyanistes caeruleus; the marsh tit, Poecile palustris) to two dummies placed near an experimental and an alternative feeder. The dummies used were the complete dummy of a sparrowhawk and a pigeon, and partly occluded (the lower or upper torso hidden in shrubs) and amputated (only lower or upper torso on the perch) models of sparrowhawks - 15 combinations altogether. The tits considered all variants of torsos to be predators. The great tit and the blue tit perceived the model with occluded lower torso as more dangerous than the one with amputated lower torso. Such discrimination between these torsos requires the ability of amodal completion. The great tit also confirms this ability as it regarded the complete sparrowhawk and the model with occluded lower torso as equally dangerous. In the remaining cases, the number of arrivals...
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Signaling between ungulates and their predators, depending on the degree of predation pressure
Vidimská, Tereza ; Komárková, Martina (advisor) ; Fuchs, Roman (referee)
The Equids are large grazers inhabiting the savannah and prairies throughout the world. They have two types of social organization, the harem or the territorial, depending on the natural environment where they live. Main predators are the large felids and canids, especially these hunting together in packs. Historically humans were also the important hunters, based on the rich archeological evidence. Fast escape is the primary antipredation strategy of equids. This strategy is supported by many morphological, anatomical and behavioral adaptations. The body construction allows them to flee immediately and to run for a long distance. Their senses are evolved extraordinary as well, primarily the olfactory and vision. The early predator detection, enhanced by the broad interspecies communication, significantly increases the chance of horses, zebras and asses for successful survival.
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The role of UV reflection in parasite egg rejection in reed warbler (Acrocephalus scirpaceus)
Šulc, Michal ; Procházka, Petr (advisor) ; Fuchs, Roman (referee)
One of the best ways how hosts may defend their clutch against brood parasitism is recognition and rejection of parasitic eggs. It has been documented that ability to percept UV light in birds affects their behaviour. By using a spectrophotometer we found that Reed Warbler (Acrocephalus scirpaceus) eggs and Common cuckoo (Cuculus canorus) eggs differ mainly in brightness but also in UV hue. We investigated the influence of birds' UV vision on recognition and rejection of parasitic eggs. Therefore we performed three experiments to reveal the role of eggshell UV reflectance on egg rejection in this host. In the first experiment, we parasitized clutches with artificial white eggs differing only in UV reflectance (UV- and UV+). In the other two, we experimentally reduced UV reflectance from conspecific and host own eggs. We used a UV light blocker, which did not influence the reflectance shape in the other parts of spectra. As a control we used a group of conspecific and own eggs coated in Vaseline, which did not affect eggshell reflectance. In each experiment, we monitored host response to parasitic eggs. Because the Reed Warbler's eggs reflect UV radiation themselves, we expected that white UV- eggs would be rejected as well as the eggs coated in UV blocker at a higher rate than white UV+ eggs and...
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Feeding ecology of the Stone marten (Martes foina) in Europe.
Nováková, Lucie ; Vohralík, Vladimír (advisor) ; Fuchs, Roman (referee)
During last decades, the stone marten, Martes foina (Erxleben, 1777) became a synanthropic animal and its population is increasing. This review is summarizing the knowledge about its feeding habits throughout Europe. In the first part the methods are introduced which are used for study of feeding ecology, for example scat analysis or the analysis of stomach and gut content. The way of calculations of some characteristic values most frequently used in study of feeding ecology of marten are described. In the second part the geographic variability and the seasonal changes in the marten's food in the different parts of Europe are analyzed. It seems that the type of habitat, in which the stone marten lives, affects its feeding habits. The differences its feeding in the urban and rural habitats are shown. There are intrahabitat differences too. In the third part of this work the main components of marten's food are described which include various small vertebrates, invertebrates (mostly insects) and fruit, and some marten's food specifics are discussed. Food resources provided by man are mentioned. Key words: feeding ecology, stone marten, Mustelidae
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Biology of three-toed woodpecker
Navrátil, Martin ; Fuchs, Roman (advisor) ; Reif, Jiří (referee)
In my thesis I have tried to find out how does forest management influence presence of the Three-toed woodpecker Picoides tridactylus.This species is considered a "flagship species" of an untouched primeval type of forest and therefore it requires our attention and protection. The thesis contains results of North-American studies focused on the species very similar to Picoides tridactylus. The main chapters are those aimed to provide information about how is the Picoides tridactylus affected by forest fragmentation, stand health condition and finally the impact of food supply on the occurence and behaviour of the species.
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Breeding site fidelity in waterfowl
Kejzlarová, Tereza ; Musil, Petr (advisor) ; Fuchs, Roman (referee)
The thesis is concerned in breeding site fidelity and focused on Anseriformes, especially Anatidae. Higher fidelity ratio in females than in males is an interesting pattern of breeding site fidelity in this bird group. On the contrary, an opposite pattern, i. e. higher fidelity ratio in males prevailed among other bird species. This study is aimed at describing this phenomenon and discussion of factors affecting fidelity ratio. Among, the most important factors, the importance of the previous breeding success and environmental conditions is underlined. The study includes data about fidelity ratio from 40 studies of breeding site fidelity in Anatidae.
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