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Biotic and abiotic factors affecting territorial and reproductive behaviour of dragonflies (Odonata)
KYBICOVÁ, Tereza
Habitat selection, territorial behaviour and reproductive behaviour of dragonflies (Odonata) are discussed and biotic and abiotic factors affecting their territorial and reproductive behaviour are reviewed. The most important biotic factors are predation risk affecting larval survival and the presence of aquatic vegetation, which provides spatial structure. The review is complemented by a field study of territorial and reproductive behavior of dragonflies at an experimental site, at which the quality of individual pools was manipulated by a combination of the presence or absence of artificial vegetation and the presence or absence of an introduced top predator (late-instar larvae of Anax and Aeshna).
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How the red-backed shrike (Lanius collurio) recognizes enemies
NĚMEC, Michal
This study investigates two questions about anti-predator behaviour of the red-backed shrike. 1) Is the red-backed shrike able to assess the differing dangers represented by various types or species of predators? 2) How does the red-backed shrike recognize the predator? We found, that the red-backed shrike (Lanius collurio) adjusts its anti-predator behaviour by assessing the potential threat to themselves from different predator species and by assessing the chance of a successful attack. Further, we found that the presence of general raptor salient features is absolutely necessary for proper categorisation of the intruder as a predator, whereas the natural species-specific colouration in itself is an insufficient cue.
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Phenotypic plasticity of planktonic rotifers as a response to predator.
VAJDIAKOVÁ, Nikola
The aim of this thesis is to assemble essential information about phenotypic plasticity of zooplankton, especially planktonic rotifers. More specifically, the thesis is focused on predatorinduced morphological changes. I introduced different types of predators and their behavioral, physiological and morphological impacts on zooplankton. Moreover, I examined the effects of inducible morphological defences on the planctic rotifers.
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Etologie a působení člověka na koně
Kupská, Anita
There are many questions about the ethology of horse. This work represents the basic review natural behaviour of horses and requirements from human to horses behaviour. The first part of this work is about ethology of horses in herd, next follow in relation of human and predator to animal. Humans often do not considerate want to change nature of horses and repressed it, they are not able to secure the optimal conditions for horses stabling, that is why is the second part about diferences of horses behaviour between breeding in stable and in free environment. It is maybe the reason of genesis the bad habits, which are in the next part of my work along with their solutions and preventiv of origins. Suitables types of stabling for horses nature are in work too. There is a proposed methology for monitoring bad habits of horses in breeders world.
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An experimental study of the feature theory: Is an eye e key stimul?
SÝKOROVÁ, Jana
The way, how birds discriminate and categorize their predators exactly, hasn't been known yet. More theoretic conceptions try to explain the mechanism of the categorization, one of them is the feature theory. The theory is based on that object is a compound of neutral and key features. We decided to examine this theory under labor conditions. We tested yellow expressive eyes of a predator, sparrowhawk, as a key stimul for recognition of predator by tits (Parus major). We used wooded dummies of the predator - sparrowhawk (Accipiter nisus) and a nonpredator - pigeon (Columba livia f. domesticus) and made chimeras between those two type that differed in eyes. Our results showed, that eyes really could be a key feature and it may works in a combination with other key stimuli.
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Effect of stimulus size in discrimination and categorization processes in birds
NÁCAROVÁ, Jana
The mechanism of predator categorization has not been understood well yet. I examined how coloration pattern and predator size influence categorization by a prey under laboratory conditions. I tested the reaction of great tit (Parus major) to the plush dummies of sparrowhawk (Accipiter nisus), coloured as sparrowhawk, pigeon, robin and great tit. The same color variations were made in the sizes of a sparrowhawk and great tit. My results indicate that the coloration plays the main role in the recognition. The size is not important in the dummies coloured as the predator and the conspecific but it plays a role in recognition of other tested dummies (coloured as the pigeon and robin).
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Influence of visibility in water column on predation pressure in predatory aquatic insects
PODHRADSKÁ, Eliška
The influence of abiotic factors on predation behaviour in predatory aquatic animals is reviewed. The most important factors are turbidity, light intensity and complexity of the environment. These abiotic factors are often combined with biotic factors. The second important part of thesis is the description of functional responses and influence of changes of visibility on individual components of predation behaviour. The review is complemented by laboratory experiments on two selected species of aquatic insects.
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Key features and prototypes in visual predator recognition - laboratory experiments with Great Tit (\kur{Parus major})
TUMOVÁ, Petra
Categorization of predators is fundamental for birds? life. However, the mechanism is not well explained yet. Two basic theories of categorization were tested in the laboratory conditions, where we have the possibility to focus on the behavior of each individuum. In the experiments we focused on the relevance of the key features and colour patterns. The responses of the Great Tit to variously modified dummies of Sparrowhawk were observed. The results confirm that the bird does not recognize the predator only on the basis of the key features and the colour patterns have a essential influence on the categorization. Categorization of the predator is a complex process and it cannot be explained only on the basis of one psychological theory. A combination of the key features and a prototype of a particular category learned throughout its life is probably used.
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