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Bioacoustics in frogs
Karochová, Lucie ; Šandera, Martin (advisor) ; Schneiderová, Irena (referee)
This thesis is focused on bioacoustics in frogs. The purpose was to compare known informations about vocalization types, influence of sexual selection on males call, chorusing behavior and influence of predation. Bioacoustics research was carried on many frog species from different part of world, with most experiments being carried on neotropical frogs, specifically Physalaemus pustolosus. Acoustics communication is a wide-spread phenomenon across the animal kingdom. The theme of bioacoustics is studied quite extensively. The most studies is focused on birds or mammals, and the study of frogs, especially the European species, is poorly known. The influence of sexual selection on males vocalization is well known, while research in other evolutionary principles such as the effect of predator is studied only marginally. Research on new types of frogs tend to focus on the description of vocalization types that occur in a given species. In addition to in detail are studied individual voice parameters such as frequency or intensity and chorusing frogs are determined mainly by call-timing or synchronization. Newly was discovered ability of some frogs generate ultrasonic harmonies and surprising discovery was female vocalization as well. Generalization of facts is quite difficult because of the lack of...
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Reproductive biology of brown frogs of the Czech Republic
Žáčková, Lucie ; Šandera, Martin (advisor) ; Vojar, Jiří (referee)
The frog reproduction biology is species-specific. Most of them, searches for water environment for reproduction. Our true frogs are no exception, they can be found in water right on the beginning of spring. For the rest of the year, the move on the land and only return to water when they intend to enter hibernation. They are also sometimes named as "land frogs" due to them spending most of their life in terrestrial environment. The true frogs look very similar and for their definition the combination of more determining attributes is used. The coloration of both sexes differs depending on time of the year in different species. The differences between males and females, but also between different species, are visible the most during the reproduction phase. Apart from coloration there are many other different characteristics. One of those is the calling of males in reproduction phase. Moreover, the species differ in the length of hibernation, the time of clutch laying or the manner of their placement in water. Many reproductive isolation barriers exist between true frog species inhabiting the Czech Republic which prevent the successful inter-species breeding. Key words: hibernation, calling, reproduction, amplexus, clutches, metamorphoses
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Information content in vocalization of guinea pigs (Cavia porcellus): individual distinction and recognition of predators
Baklová, Aneta ; Baranyiová, Eva (advisor) ; František, František (referee)
Guinea pigs represent domesticated precocious rodents which became common pets. From the first day after birth they are fully vocal. This thesis was devoted
to the vocalization of pups. The aim of the thesis was to 1) determine the age when the vocal individuality in whistle sound is demonstrable; 2) test possible ultrasonic signals emitted by young guinea pigs; 3) study the antipredator reactions and alarm calls to aerial (bird of prey) and terrestrial (dog) predators and human (control test).
A total of 16 guinea pig pups were tested for vocal individuality, 28 pups
for ultrasonic vocalization and 27 adolescents for predator recognition. When testing vocal ontogeny during the first 9 days after birth, I observed changes in temporal, frequency and parameter of intensity . When I test vocal individuality by cross-validated discriminant function analysis (DFA) based on ten acoustic parameters, calls were classified to correct animals with following success: day 1 = 71.9%, day 3 = 58.8%, day 5 = 53.10%, day 7 = 50.60% and day 9 = 63.10%. The highest frequency in whistle was 30.03 kHz. In predator discrimination reactions as freezing, fleeing and vigilance were observed. In the presence of dog, guinea pigs reacted for the longest time and most frequently by freezing. When confronted with a bird of prey, I observed for a longest time and most often fleeing and then freezing. When exposed to a human, guinea pigs showed mostly vigilance. Almost no vocalization was observed except for two events
of alarm calls - drrr as in the presence of dog and chirrup as reaction to bird of prey.
The following conclusions can be drawn from the presented results: 1) vocal individuality of guinea pigs is demonstrable immediately after birth and the rate
of individually different vocal parameters changes with age; 2) guinea pigs are able
to produce sound up to 30 kHz, i.e. within the ultrasound range, but signals of high frequencies are not crucial for their communication; 3) guinea pigs discriminate between terrestrial and aerial predators, but they emit alarm calls rather rarely.
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The ontogeny of vocalisation in gibbons Nomascus
Hradec, Michal ; Bartoš, Luděk (advisor) ; Pavel, Pavel (referee)
Knowledge of the ontogeny and development of vocalization in primates play a crucial role in understanding the evolution of the human language. Unlike the great apes, gibbons produce a remarkable vocal performance, which includes complex species- and sex-specific patterns. Many studies in the past focused on research of the acoustic pattern in adult individuals. Yet, it remains unclear how the males develop their sex-specific pattern of vocalization.
This dissertation focuses on two specific periods in the ontogenetic development of acoustic structures in male Northern-white cheeked gibbons (Nomascus leucogenys) and Southern-yellow cheeked gibbons (Nomascus gabriellae). The results showed that the first time immature males (juvenile and adolescent) produced female acoustically structured great calls in duets with their mothers. How the great call was structured in immature males differed from the great call of their mothers; the difference being in spectro-temporal parameters from. The most significant difference between juvenile and adolescent males in the production of female vocalization was the presence of a twitter vocalization towards the end of their call. The results show that the twitter was a regular part of female vocalization in juvenile males around four years of age, while younger males produced this vocalization exceptionally. The second period in the ontogeny of vocalization in immature males (adolescent) was characterized by the fact that after five years of age, the development of the male acoustic structure begins. During this period, we did not observe the production of the female vocalization great call in any of the monitored Nomascus gibbon individuals. Results show that the ontogenetic process of the male song in Northern-white cheeked gibbons (N. leucogenys) did not develop in the same sequence as in adults which produced different notes and phrases. The immature male (adolescent male) first time developed the multi-modulation phrase (coda) and the staccato note (syllables) simultaneously at the beginning of this study, but, it was observed that they started producing the boom note four months later. Conversely, the development of the acoustic structure in male Southern-yellow cheeked gibbons (N. gabriellae) was characterized only by the development of a multi-modulation phrase. Development of the staccato syllables was not noted in this species during the study. The results support the interpretation that the development of the male acoustic structure closely corresponds to the growth of the vocal tract and physiological changes associated with reaching sexual maturity.
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The impact of noise and light pollution on voice activity of Chiffchaff (Phylloscopus collybita)
Žilinčíková, Nikola ; Hodačová, Lenka (advisor) ; Kočicová, Pavlína (referee)
The continuing growth of the worldss population causes increase of anthropogenic influence on environment. In this mechanized times the often observed factors with influence on (not only) birds populations, are light and noise. These factors of environment can have negative impact on birds song and behavior related to it. Vocal expression is essential for communication of bird species and is necessary for their life processes. The birds are therefore, under the influence of stressors, forced to adapt themselves to newly emerging environment. This work investigates the influence of light and noise pollution on vocalization of chiffchaff (Phylloscopus collybita) during the morning and evening hours. The obtained data came from 4 types of locality (light-polluted, noise-polluted, light-noise polluted and without pollution) where the factors were represented predominantly by the noise of traffic and by artificial night lighting. Localities with presence of chiffchaff were selected and voice recorder was then placed into his territory. The obtained records of his voice were subsequently analyzed. The recording was done since April until May 2015, solely during the good weather conditions (without storms and strong wind). A development and intensity of the birds song were compared. The spotted result was a shift of chiffchaff´s morning vocalization initiation under the influence of light and noise pollution and increased intensity of birds song in the morning hours, in the locality affected by light and also in the noisy locality during the sunset.
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Breeding and vocalization of the Forpus parrots species
Albrechtová, Šárka ; Zita, Lukáš (advisor) ; Ledvinka, Zdeněk (referee)
This Thesis is a summary of available sources on the topic of the pet breeding of Forpus parrots and their vocalization. Since the parrotlets became best known in Czech republic as pets 35 years ago, they are not that common as other small species. However it was their vibrant colouring, pleasant vocalization and low breeding demands that enchanted the breeders.
In the first part of the Thesis, there is introduction on the taxonomy of the species with emphasis on its history and still changing presence. Also there is general description of the biology of each of the species and subspecies in the nature with their localization.
The second part consists of information on the topic of hobby breeding. It summarizes current findings in the form of breeder's advice including information about successful breeding and also emphasises the epizootiology.
The last part is dedicated to the topic of vocalization because parrotlets are one of a few species that are capable of referential vocalization. So there is a brief anatomy of syrinx, types of calls and details about referential vocalization. Also, findings from the last 30 years of research are mentioned.
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The impact of noise and light pollution on voice activity of Blackbird (Turdus merula)
Vlach, Martin ; Zasadil, Petr (advisor) ; Musilová, Zuzana (referee)
Abstract
Cities represent a new environment where organisms are exposed to different environmental conditions than the original natural habitats. This is essentially a noise and light pollution. The growing number of studies show that these factors can have a significant impact on voice activity of birds.Light pollution may alter the timing of vocalization.Urban noise can overlay the acoustic signals of birds, change the melody, volume, and the timing of singing. The main objective of this thesis was to investigate the influence of noise and light pollution to voice activity Blackbird (Turdus merula). In 2015 it was recorded vocalizations to 4 types of sites: a) on the site only with noise pollution (unlit busy road), b) on the site only with light pollution (Parks), c) on location with noise and light pollution (busy roads in cities), d) on the site without the noise and light pollution (forests). Recording was done with the help of voice recorders from early March until the end of May when the weather was good (no strong winds and storms) every week to thoroughly map the seasonal voice activity of the birds. Quiet location and localities with noise pollution have been in the woods near the town of Beroun near the D5 highway. Locations with light and noisy pollution is found in Hradec Kralove and Prague. In each locality they were searched individuals Blackbird and placed recorder into their territory. The recordings were taken 180 minutes before sunset, throughout the night and morning was the end of the recording 180 minutes after sunrise. The results showed the influence of the sites primarily on the morning vocalization when in the localities affected by light and noise vocalized significantly earlier than the quiet and noisy areas. In the evening times was vocalization without significant differences. The greatest intensity of vocalizations Blackbird was light-noisy areas, opposite to others. The evening was the greatest intensity of the sound recorded in quiet locations. Finally, the night vocalization has been demonstrated only in localities light-noisy.
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Clicking in bovids - basic parameters, origin and function?
ROCHOVÁ, Markéta
Some species of hoofed animals produce clicking sound. This work analysed clicking parameters (dominant frequency, 25% quartile, 50% quartile, 75% quartile) of this species: Kuban Tur (Capra caucasica), Daghestan Tur (Capra cylindricornis) and Aoudad (Ammotragus lervia), which are clicking significantly. Clicks of each individual were recorded using solid state recorder Marantz PMD 620 with microphone. All clicks were analysed using program Avisoft-SAS Lab Pro Software, verze 5.0.01 (2010). Data were analysed using program STATISTICA, version 9 (ANONYMUS 2009). Individuals were compared using one-way ANOVA and discriminant analysis. Species and sexes were compared using discriminant analysis and nested ANOVA. Clicking parameters were correlated with age. A phylogenetic distribution of clicking was determined in Bovidae. Results suggest differences between individuals and species. Differences between sexes wasn't significant. Correlation with age was significant.
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