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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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Variability of specific structures Tree Pipit
Kozlová, Zuzana ; Petrusková, Tereza (advisor) ; Musilová, Zuzana (referee)
Primary function of birdsong is for territorial defense or attraction of females. Birdsong also contains much more other information and can be used to inform males and females about quality of singing bird. It was demonstrated, that for different bird species condition of male correlates with what structures of birdsong are produced. More complex structures are produced by superior males. Females of some species prefer males with ability to produce more complex structures. This work deals with structures of singing of the tree pipit species (Anthus trivialis). These structures are also known as trills. It is assumed, that trills may contain some information about quality of male, which can be evaluated by males and females. Birdsong of tree pipit contains two types of trills - loud and soft. Loud trills are used in aggressive interactions between two males. Soft trills are not used in aggresive context and they differ in consistency - regularity, that can be expressed as tempo of trill. When measuring tempo of trills for every tree pipit male, the tempo is different among males and also correlates with their ability to maintain stable territory over the entire nestling season. Males with faster (more consistent) tempo of trill had stable territory, while males with slower (irregular) tempo of...
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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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Results of nesting and breeding of some species of birds Family (Timaliidae, Passeriformes) in the zoo Praha
JANDOVÁ, Ivana
Babblers together with the close related Timallidae are not very common inmates of the zoological gardens. In the Czech Republic they are only bred in the zoological gardens in Ohrada, Pilsen and Prague. The breeding in the zoological gardens is not generally very successful. The zoo in Prague with its number of species owns the largest collection of these birds in Europe. In the past the breeders in Prague were the first ones in Europe who managed to raise for example Rufous-fronted Laughingthrush, Sunda Laughingthrush, Barred Laughingthrush or Sumatran Laughingthrush (Black-and-white Laughingthrush). As the first ones in the Czech Republic they were able to reproduce the critically endagered Blue-crowned Laughingthrush (Courtois's Laughingthrush). The Blue-crowned Laughingthrush is so rare that for several years it was not clear at all if they still live in nature. In the year 2000 they were rediscovered in the number of 240 pieces. The quantity of them in the zoological gardens all over the world does not exceed 100 pieces. The zoo in Chester does a European breeding book of these pieces. Some birds in Prague reproduce repetitively and they prove that the right method of the breeding was found. Hopefully this method would lead to the birth of the securing population in the care of humans. This securing population is very important for the protection of these birds. The attempt of this work is to assess the links between the results of the breeding and their conditions, the comparison of the nesting activities of the two chosen species of babblers, then the summarizing of the expansion and the results of the breeding of the individual species and also the processing of the expansion, the development of the quantity and the problems of the protection of the babblers in nature. The following facts were found out: the breeding of the birds in the exposition or in its environment does not have an essential influence on their nesting activity. However, for the nesting activity it is more important if they are a newly formed couple or a couple paired for a longer time and at the forest babbler it is the female that has an important role in incubation period. However, at the Sumatran Laughingthrush there is a frequent changing in different time intervals. The work also shows that only 5 species out of 12, that showed the nesting activity, are able to build a nest without the help of the keepers. That can be attributed to their closer relational breeding and also to putting the higher number of artificially reared individuals into the breeding.
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