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Acoustic communication in two species of ground squirrels Spermophilus citellus and S. taurensis (Sciuridae; Rodentia).
Schneiderová, Irena ; Vohralík, Vladimír (advisor) ; Petrusková, Tereza (referee)
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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Acoustic communication and its variability in selected populations of ground squirrels of the genus Spermophilus
Schneiderová, Irena ; Vohralík, Vladimír (advisor) ; Sedláček, František (referee) ; Špinka, Marek (referee)
The thesis deals with vocalizations produced by Eurasian ground squirrels of the genus Spermophilus. It is mainly focused on inter-species and intra-species variability in acoustic structure of alarm calls which are emitted in presence of predators.The major part of the thesis deals with intra-species variability in acoustic structure of the alarm calls in five Eurasian ground squirrels, Spermophilus citellus, S. taurensis, S. xanthoprymnus, S. suslicus and S. fulvus. It has been confirmed that the alarm calls of these ground squirrels show a high level of species specificity. The thesis further describes another vocalizations produced by three Eurasian ground squirrel species, Spermophilus suslicus, S. citellus and S. fulvus, and shows that with the exception of the alarm calls, vocal repertoires of these three ground squirrels are remarkably similar. The last part of the thesis deals with individual distinctiveness of the alarm calls of three Eurasian ground squirrels, Spermophilus citellus, S. taurensis and S. xanthoprymnus. It has been shown that the alarm calls of these species have a significant potential to encode information about caller identity.
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Racoon dog (Nyctereutes procyonides) in Central Europe: history of range expansion and current state of knowledge
Pyšková, Klára ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
The thesis is about the raccoon dog (Nyctereutes procyonoides), a canid invasive in a large part of Europe. It describes its distribution in native and invaded range, the history of colonisation, ecology and social behaviour, as well as its impact in the invaded range. Available knowledge is summarized, with main focus on central Europe. The native distribution range of the species is in eastern Asia. The animals were first brought to the European part of the former Soviet Union in the first half of 20th century for breeding at fur farms, and later being released into the wild for hunting. The raccoon dog colonised 1,4 million km2 over the next 50 years, and became an established carnivore common in many European countries. A number of factors influenced the successful invasion; an opportunistic feeding strategy and high habitat adaptability; repeated and numerous introductions over a long period of time, resulting in a high genetic variability; the ability to hibernate; low numbers of predators; the tendency to wander, sometimes to quite distant areas; and high intraspecific tolerance. The environmental and economic impact of raccoon dog seems to be rather low, and the most dangerous aspect of its invasion is the transmision of infectious diseases, mainly rabies.
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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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Genus Sicista (Mammalia, Rodentia) in the fossil record of central Europe: phenotypic variation, taxonomic structure, range dynamics.
Lišková, Tereza ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Member of the genus Sicista rank among the rarest and the least known European mammals. They exhibit a number of outstanding specificities (hibernation, aestivation etc.) and extreme capability of a rare range dynamics. Their fossil record is fragmentary and associated with numerous controversies. The present thesis summarizes results of a detailed revision of the fossil record of Sicista from Czech Republic, Slovakia and some other countries. It comprises of about 150 items of the Holocene and Vistualian age as well as from the Middle and Early Pleistocene including earliest records from MN17/Q1 boundary and type material of S. praeloriger from Q1 Betfia. Compared to a sample of extant population, variation dynamics of both metrical and nonmetrical dental traits was examined in details with particular attention to phenotype patterns of particular fossil samples. The results demonstrated extensive amount of both within- and between-population variation and rather limited validity of commonly used discrimination criteria of extant clades. Nevertheless, we succeeded in species identification of considerable part of numerous Holocene and Vistulian records which revealed (i) a range expansion of S. subtilis s.l. during MIS 3 with persistent distribution in lowland regions of Central Europe in the Late...
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Genus Neomys (Mammalia, Eulipotyphla, Soricomorpha): history and range dynamics.
Pažitková, Barbora ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Based on numerous literary sources, the thesis reviews current knowledge of history and range dynamics of the genus Neomys, an indexing element of the west Palearctic mammal fauna. It provides a list of fossil records attributed to the extant genus Neomys and extinct clades composing the European records of tribe Nectogalini, and a survey of hypotheses on their phylogenetic relations. Particular attention is given to the genus Asoriculus which is generally considered as an ancestor of the Quaternary radiation of the clade represented in Europe with genera Nesiotites, Neomys and Macroneomys. The transition from Asoriculus to Neomys is expected to appear during the Q1 stage of the Early Pleistocene, more records identified as fossil species of the latter genus are reported from terminal stage of the Early Pleistocene (Q2). Nevertheless, their relations to extant species were not analysed and past history of the extant European taxa (fodiens, anomalus, milleri) and their range dynamics is despite of molecular data generally unclear. This fact reflects both scarcity of the fossil record and uncertainties regarding patterns of phenotype variation in particular species, their discrimination criteria and orientation of corresponding phylogenetic morphoclines. In these regards, the thesis pays special...
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