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Potravní neofobie u obratlovců: mezidruhová variabilita, její příčiny a důsledky
SEM, Lukáš
The thesis summarizes existing knowledge about the phenomenon of food neophobia in vertebrates. It describes interspecies and intraspecies differences in the level of food neophobia, looks for evolutionary and ecological factors that influence the level of food neophobia. It introduces the role of sociality in the induction and suppression of food neophobia.
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Status of the flatworm Crenobia alpina in the food network of a spring
Reslová, Marie ; Simon, Ondřej (advisor) ; Černý, Martin (referee)
This work focuses on food preferences of freshwater triclad Crenobia alpina and its position in spring food web. It explores the ability of C. alpina to capture living prey, considers ability of C. alpina and to survive feeding on several types of food. Furthermore it gives view on its occurence and ecological preferences in context of other spring species. One chapter is concerned with taxonomy, anatomy and ecology of Tricladida and C. alpina itself. Short term food-preference experiments show the ability of C. alpina to capture living Lumriculidae and larvae of Ephemeroptera. We don't confirm feeding of C. alpina on living Gammarus, although their occurence in our springs and ecological preferences are similar. C. alpina feeds significantly more on damaged prey without substantial afinity to any species. A year-long experiment on C. alpina in lab conditions finds that this flatworm is able to survive and even breed with nothing but filtred water. This fact connected with the observation of huge densities of flatworms in spring source, opens up a question whether C. alpina can be considered a real predator. Key words: Crenobia alpina, triclad flatworms, food preferences, spring
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Food neophobia and food preference in rodents (Rodentia) and its interaction with social learning.
Rudolfová, Veronika ; Landová, Eva (advisor) ; Telenský, Petr (referee)
Neophobia (fear of novelty) is first protection from ingesting potentially dangerous food in rodents. After overcoming the fear an animal begins to sample the food (take small parts). The animal then forms an aversion to dangerous food and preference for safe and nutritionally favourable food on the grounds of its experience with its ingestion. These mechanisms of behaviour towards food can be learned individually but an individual's behaviour is also influenced by other animals, especially in social animals. Whether an individual will act on its own experiences and therefore learn or if it will learn from others, depends on the situation and the environment in which the animal currently is. Key words: food neophobia, food preferences, social learning, individual learning, Rodentia, Rattus
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Foraging strategies of invertebrate predators in mountain lakes
Hrdličková, Jana ; Sacherová, Veronika (advisor) ; Hořická, Zuzana (referee)
In mountain lakes, which were affected by acidification in the past or in the present, invertebrate species have become top predators and they influence the whole community. This thesis deals with foraging strategies of three of these predators, Cyclops abyssorum and Heterocope saliens (Crustacea: Copepoda) and Glaenocorisa propinqua (Insecta: Heteroptera) in the model localities Černé lake, Plešné lake and Prášilské lake. The main aim was the determination of food composition and food preferences of these predators. The quality and quantity of consumed food I investigated with a microscope using a method which has not been published yet. To make a microscope preparation I used Potassium hydroxide or Lactic acid in order to dissolve soft organic matter, so that the chitinous particles were well visible. The found food of animal origin was subsequently compared with the prey availability with the use of Jacobs' index. In addition to this research, a feeding experiment with G. propinqua was carried out. The food of all the invertebrate predators was dependent on food availability or eventually on the season of the year. G. propinqua mostly preferred as a prey members of Daphniidae family and then the species Polyphemus pediculus (Cladocera), if they were available (Prášilské lake). In Plešné lake,...
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Stable isotopes and the study of insects ecology
Javůrková, Jaroslava ; Šípek, Petr (advisor) ; Harant, Karel (referee)
Animal foraging ecology is an important part in the puzzle ecosystem relationships. This bachelor thesis presents review in the field of food ecology, especially insects. It focuses on the method of analysis of stable isotopes, which is one of the current and in recent decades a modern approach for studying this issue. Stable isotope analysis is compared with other frequently used methods for animal food ecology. The aim of this work is to introduce this method and its possible use in the study of insect food ecology. The first part provides the necessary theoretical background, practical application in laboratory and then it deals with the problems typically adressed by this method. Key words: stable isotopes, stable isotopes analysis, food ecology, food preferences, insects
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Potravní ekologie koní v kontextu ochranářského managementu krajiny
HÁJKOVÁ, Pavlína
This thesis provides a review of knowledge available on wild and feral horse feeding ecology, habitat preferences, competition overlap with other herbivores and their impact on vegetation. In summary, horses appear valuable for management of grasslands, but less suitable for regulation of shrubs and trees, especially when they are compared to cattle and cervids, which are more able to eliminate woody plants. Together with a tabular overview of literature on feeding ecology and plant taxa eaten by horses in the Holarctic realm, an optimalized protocol is provided to facilitate proper field collection of data about the feeding ecology and behavioral repertoire in large ungulates.
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Výskyt bobra evropského a dopad jeho činnosti na břehové porosty v oblasti Strážnice
Maša, Marek
The bachelor thesis deals with an occurrence of European beaver (Castor fiber) in four different areas in the neighborhood of Strážnice. Number was charted on the basis of tracks of beaver's stay using Djak's method, also finding out preferred woody plants and suggestion of possible measures against reduction of damages on bank vegetation. The method is based on principle of addition of perfect and imperfect gnaws and their division into thickness classes. Measuring was under way from February to March of 2014. None of areas isn't newly settled and beaver is found for a few years in this place.
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Use of Slugs in the Elementary and High School Teaching
Šrámková, Jiřina ; Říhová, Dagmar (advisor) ; Kocurková, Alena (referee)
The present work aims to familiarize students with current representatives of naked snails. In the Czech Republic there are five families of naked snails (Agriolimacidae, Arionidae, Boettgerillidae, Limacidae and Milacidae) and all their representatives are characterized by the loss of a secondary shell. Working closely represents ten of them. Part of the work is simplified determination dichotomous key and atlas. Basis of the thesis is a proposal of nine laboratory exercises, observations and experiments that pose naked snails from many angles, from basic observation of the external morphology through the food demands and sensory perception until after the autopsy. Tasks are designed for use in high school; Simplified variant may serve základoškolským hours practically oriented science. Some of the presented tasks (monitoring food preferences, sensory perception and response to stimuli) can be extended to a project day or protracted class of biologically oriented project. All designed tasks were tested. The most important model species of this thesis is the Spanish slug (Arion vulgaris (Moquin-Tandon, 1855)). It is a Czech non-native, invasive representative of the family Arionidae. Thanks laboratory exercises contained in the work of pupils, it is possible that the snail introduce in detail and...
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