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Testing of functions of song types and specific structures of tree pipit song
Kinštová, Anna ; Petrusková, Tereza (advisor) ; Riegert, Jan (referee)
4 Abstract Bird song is usually considered to have two primary functions; attract females and repels males. Hence, song features can be an indicator of male quality or aggressive motivation. It has been suggested that one of those features could be in the form of a trill - physically demanding structures. Two types of trill has been found in tree pipit, Anthus trivialis, "I" and "M" trills. Trill rates significantly differ among males in this species therefore we assume that repetitive syllable production may indicate male quality. Firstly, we tested if both types of trills are used in aggressive context using playback experiments. Only "I" trills were sung by males in response to playback, regardless of the type of trill involved in playback. Moreover, males increased the frequency of the singing of that trill as an immediate response to playback, and also increased the trill rate in comparison with spontaneous songs. In addition males who sung faster "I" trills were able to maintain the territory. We conclude "I" trills may carry information about the signaller's aggressiveness. Surprisingly, production of "M" trills decreased after the simulated territorial intrusion. Secondly, we tested hypotheses that males modify their response according to the intruders' quality therefore we used playbacks containing...
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Bird of the Year 2011: involving public in the analysis of regional variation of bird songs
Diblíková, Lucie ; Petrusková, Tereza (advisor) ; Reif, Jiří (referee)
The yellowhammer (Emberiza citrinella) is a common bird of open areas whose song exhibits easily distinguishable dialects. The dialects are tied to the final part of its song. Some, especially older publications claim that yellowhammer's dialects can be divided into two broad groups with predominantly Eastern and Western European distribution, with a borderline intersecting Central Europe. Until recently, yellowhammer dialects have only been thoroughly researched in Denmark and in some parts of Germany. In the Czech Republic, a detailed study was carried on in connection with the"Bird of the Year"campaign, during which the general public was involved in collecting song recordings at various localities. Thanks toa project called "Czech Yellowhammers Dialect", more than 2600 recordings from throughout the Czech Republic were collected within three years. The recorded songs were then classified into one of the seven traditionally acknowledged groups; some new, not yet documented ones were also discovered. The distribution of the dialects generated a dialect mosaic with a clearly established borderline between individual dialects. Mixed singers were found along the borderlines. A borderline between two dialect groups, crosscutting Western Bohemia, was also found. It was proved once again that for a success of...
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Inter-population variability of the bird song
Bílková, Jana ; Petrusková, Tereza (advisor) ; Musilová, Zuzana (referee)
Inter-population variability of the song is widespread phenomenon among birds. Populations of same species from different geographical areas might differ in vocalization. In case of dialects there are even no transitions between particular song forms, but clearly demarcated boundaries. Although the majority of studied cases concerns songbirds, it is possible to find examples in other orders as well. Studies showed that individuals inhabiting forests sing shorter and simpler songs with a lower frequency than their relatives from open landscapes. Changes in temporal and frequency characteristics can also be found in populations living in noisy cities. Different songs, however, are also produced by individuals from populations whose habitats do not show any significant differences. If these groups also differ genetically, then the different variants of song could be caused by heredity, especially in species with innate song. However, this variability may be the consequence instead of the cause of assortative mating, which might be the result of interpopulation variability in some cases. In species where the song is at least partially learned it is more likely that social interactions will play the key role - particularly if females prefer males singing local dialect or if sharing the song with neighbors...
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Yellowhammer as a model species for studies on passerine dialects
Diblíková, Lucie ; Petrusková, Tereza (advisor) ; Procházka, Petr (referee)
Even though birdsongs and bird dialects have been subject to considerably intense scientific research, the domain of bird dialects is still worth attention of scientists. There is a large number of hypotheses about the emergence of bird dialects which separately or combined explain their origin. Dialects can be classified on the basis of the structure of a birdsong which they are related to or according to a geographical scale (micro and macrodialects). Research on bird dialects belongs to such type of studies that require great amount of data and thus large amount of time and finance is needed. Nonetheless, this obstacle can be avoided by involving general public into the research, however choosing a suitable model species is necessary. Yellowhammer (Emberiza citrinella), which was chosen in this study, is undoubtedly a convenient species for its common occurrence and distinguishable birdsong. Yellowhammer males sing during a large part of the season and their dialects can be easily recognized. Moreover, some scientists differentiate between macrodialects, that should be divided across western and eastern Europe, and could be used to make the research more attractive for general public. Till now yellowhammer dialects have been thoroughly explored in Denmark and in some parts of Germany, but in other...
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Repertoire and specificity of vocalization in Grey parrot (Psittacus erithacus)
Kůrková, Petra ; Lindová, Jitka (advisor) ; Petrusková, Tereza (referee)
The aim of the study was to map the repertoire of vocalization of four wild-caught grey parrots (Psittacus erithacus), two males and two females. Data were collected during nine days from June to November 2008 by recording of vocalization in standardized conditions. Recorded sounds (3 052) were categorized according to their characteristics using both visual inspection of spectrograms and listening. We found 70 different call types, which were combined into 18 bigger groups. We found no subject to use the whole repertoire. Important differences were found both between individuals and between males and females. almost all call types were used throuthout the whole period of recording. Model spectrograms of all call types are shown. Key words: grey parrot, Psittacus erithacus, repertoire, vocalization
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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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Functions of repertoire size in passerines
Kinštová, Anna ; Petrusková, Tereza (advisor) ; Musilová, Zuzana (referee)
5 Abstract Songbirds use visual and vocal signals to communicate. Visual signals have several disadvantages, for example they are more difficult to detect in darkness or poor light. On the contrary vocal signals, the most typical and advanced way of communication in passerines, can be noticeable even in these conditions. Vocalizations can be divided into songs and calls. The two main functions of a song, especially in songbirds living in temperate zone, are to defend a territory and to attract a mate. The songbirds have a considerable variety in songs among particular species. Moreover, the individual of the same species can differ greatly in their repertoire size. This means they have different number of song types or syllables. Currently we assume that repertoires have arisen in response to widespread female preference for mates with larger repertoires. The evolution of repertoire complexity was driven by a sexual selection of females preferences. In this case the repertoire size is considered to be a phenotypic trait which should work as an honest indicator of male quality. Therefore females could obtain direct and indirect benefits. I study the functions of repertoire size in passerines in my bachelor thesis. I focus in particular on possible benefits that females could gain from pairing with males with...
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Functions of different song types and song structures in songbirds
Pišvejcová, Iveta ; Petrusková, Tereza (advisor) ; Linhart, Otomar (referee)
In this review I summarize information about different types of song and its structures in which has been well documented their context of use. I have tried to find out, if there are some generally valid rules. The work is aimed at Passerines (Passeriformes) males living in the temperate zone. They sing the most intensively after their arrival on breeding grounds in early spring. Depending on a species and moreover an individual, the song might differ in structure, time and frequency parameters. Some species use complex songs, and change the way of its production according to attending audience. In such cases, the length and versatility of the song (the number and variability of syllables) may reflect the quality of a male. On the other hand some species with a simple song use different criteria to assess the singer quality. The individuals then differ in the way of song production or just in use of particular structures. For example, wide frequency range and length are considered to be energy-demanding for production, and so it could be a suitable indicator for a male quality. Short syllables produced at a faster rate can be not only production-demanding but can also indicate aggression. In general, we can estimate the function of a produced song according to "mating status" (before and after pairing) and...
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Acoustic communication in two species of ground squirrels Spermophilus citellus and S. taurensis (Sciuridae; Rodentia).
Schneiderová, Irena ; Petrusková, Tereza (referee) ; Vohralík, Vladimír (advisor)
6 ABSTRACT Since now, acoustic communication and alarm calls of European ground squirrel and the recently described S. taurensis have been poorly studied. Aim of this study is to make first steps in studying and understanding their acoustic communication and alarm calls. It was found, that the European ground squirrel produces 6 vocal (growl, rapid growl, scream, squeak, chirp, whistle) and 1 nonvocal (tooth chatter) sounds. These sounds are produced when sousliks are directly threatened by predator or during their social contacts. The alarm call of European ground squirrel as well as of S. taurensis is the whistle. It usually consists of two different elements, which can be fused, overlapped in time or separated by short interval. The first element has a constant frequency, while the second one has little frequency modulation. In some cases, one of these elements can be missing. The study reveals individual variation in the alarm calls in both species. Sexual differences in alarm calls of S. taurensis were found. Keywords: Spermophilus citellus, Spermophilus taurensis, Sciuridae, ground squirrel, antipredator behaviour, acoustic communication, vocalization, vocal repertoire, alarm call.
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