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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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Effect of a dummy on behaviour of Yellowhammer and Chiffchaff males in playback experiments
Kubátová, Hana ; Petrusková, Tereza (advisor) ; Veselý, Petr (referee)
A playback experiment in which a recording of vocalization is played to the tested subject and its response is observed, is a widely used tool for examining bird song and its functions. Most often only acoustic stimulus is used, but sometimes a visual stimulus is also provided in the form of a dummy. Taxidermic mounts or models made from different materials are used as the dummy. It is discussed among researchers, whether it is or is not necessary to use a dummy in experiments and how does its presence affect behavior of the tested individuals. However, only few studies directly focus on this issue and test the effect of dummies. The best way to test the effects of a dummy on passerines in playback experiments is to test the same individuals in both situations (with a dummy and without a dummy) and compare the reactions. The aim of this theses was to perform such experiments on Chiffchaff (Phylloscopus collybita) and Yellowhammer (Emberiza citrinella) males and to find out whether they would behave similarly in both variants of the experiment, or if their reaction would be enhanced in the presence of a dummy. Chiffchaffs reacted significantly more aggressively in the dummy experiment. The biggest difference was time spent by attacking the dummy and staying close to it. In Yellowhammers, the dummy...
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Effect of a dummy on passerine behaviour in playback experiments
Kubátová, Hana ; Petrusková, Tereza (advisor) ; Linhart, Pavel (referee)
Playback experiment is a frequently used method for the scientific research of the bird song and its functions. A recording of vocalization is played in the territory of the tested male, and its responses are observed. Majority of the studies using playback recordings presents only the acoustic stimulus. Sometimes a dummy is also used to provide a visual stimulus. This review focuses on the effects of the dummy on the passerine behavior in the playback experiments. In the first part a comparison is made within the groups of experiments with the same field of interest. The main questions are: how often is a dummy used in these types of experiments, how do designs and results differ depending on its presence/absence and, if possible, how do researchers evaluate its use. Subsequently, I tried to compare experiments with and without dummy within same species, but because of the differences of the experimental designs and the differences in forms of presentation the results, which were often not comparable, it was difficult to make clear conclusions. Next part analyses the few available studies where both trials with and without a dummy were performed on the same individuals. The review shows that the dummy allows tested males to express additional behavioural patterns, which can be noted by the...
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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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Being angry, singing fast? Signalling of aggressive motivation by syllable rate in a songbird with slow song
JAŠKA, Pavel
In this study, we focused on the role of syllable rate in territorial interaction of chiffchaff males. We confronted each tested male with one of three playback types which differed in song rate (slow, non-manipulated, fast). The behaviour and the song of each subject were recorded before, during and after the treatment. Males that attacked the loudspeaker during playback sang faster before the stimulation. When birds continued singing during playback they increased syllable rate when exposed to fast or non-manipulated song. Our results indicate that syllable rate could be a signal of aggression in chiffchaff and play a role as a conventional signal rather than a handicap signal.
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