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Rozpoznávají sýkory kukačku obecnou (\kur{Cuculus canorus}) od krahujce obecného (\kur{Accipiter nisus})?
ROTOVÁ, Alžběta
The thesis includes a review of the topic of brood parasitism, with focus on the most common European brood parasite, the common cuckoo (Cuculus canorus). Experimental part of the thesis tests the responses of two titmice species (Parus major and Cyanistes caeruleus), which have virtually no experience with cuckoo brood parasitism, to presented dummy of cuckoo adult. The visual appearance of the common cuckoo importantly resembles the Eurasian sparrowhawk (Accipiter nisus), and it is supposed that this similarity protects cuckoo from attacks of adult host birds. Thus I tested the theory that titmice mistake the cuckoo for the sparrowhawk, which affects their nest defence behaviour.
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Conspecific brood parasitism: a case study on the common pochard and the barn swallow
Petrželková, Adéla ; Hořák, David (advisor) ; Musil, Petr (referee) ; Guillemain, Matthieu (referee)
Presented thesis is mainly concerned with the conspecific brood parasitism (CBP) in birds. CBP is an alternative reproductive strategy when a parasitic female lay egg or eggs to other (host) female's nest of the same species. Then the parasitic female leaves the host's nest and does not provide any energetic investment in a subsequent parental care. Distinguish parasitic eggs or young is problematic because there are no obvious morphological differences. Thus, the use of molecular method is crucial for proper determination of CBP. CBP can be used as 'a best-of-bad-job' when female does not have her own nest or lost her nest for example through predation. Other option is that female can increase her fecundity ('fecundity enhancement' hypothesis) when she lay parasitic egg/eggs and care about her own clutch afterward. Two different model species were studied. The first one was a precocial diving duck - the common pochard (Aythya ferina; Anseriformes; Anatidae). Protein fingerprinting was used for detection of CBP and for distinguishing between eggs of individual females. It was found that the rate of CBP was relatively high in this species (91%, 72%; Chapter 1, 4). Further results indicated that the host clutch size decreased with the number of parasitic eggs in the clutch. The study of individual...
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Population dynamics of Red-crested Pochard (Netta rufina)
Poláková, Klára ; Musil, Petr (advisor) ; Storch, David (referee)
This study is aimed at analysis of long-term and short-term changes in numbers of Red-crested Pochard (Netta rufina) in Třeboň region. This species is increasing in long-term period and it is also spreading into new localities in the Czech Republic. There were recorded two waves of arrival of Red-crested Pochard arrive, i.e. in April and in May. The total numbers were decreasing at the end of breeding season (from the beginning of July) in study area. The water surface area and area of littoral vegetation were found to be the most important factors affecting preference of individual ponds in pre-breeding season. Furthermore, water transparency seems to be important factor affecting numbers of broods, ducklings and adults in post-breeding season. Low numbers of broods per 1 female were recorded in years with high numbers of Red- crested Pochard at the start of breeding season. However, the frequency of brood parasitism was higher in these years. Key words: Netta rufina, Red-crested Pochard, population dynamics, ducks, breeding, numbers, brood parasitism, south Bohemia
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The role of ultraviolet light in communication of birds
Šulc, Michal ; Sedláček, Ondřej (advisor) ; Albrecht, Tomáš (referee)
Recently, it has been found that the visual system of birds and humans differ remarkably, especially in the ability to perceive ultraviolet radiation. This component of the spectrum significantly affects various types of the birds' behaviour. UV reflection may be an indicator of the qualities of males, i.e. females often prefer individuals with expressive UV ornamentation. Likewise, parents can distribute the delivered food unevenly among their nestlings, depending on the nestlings' reflection of ultraviolet radiation. Recent studies also showed that the hosts of brood parasites may use UV spectrum as a key for recognizing the parasitic eggs from their own. The aim of my bachelor thesis is to review the current knowledge of the influence of UV radiation on sexual selection of birds, the interaction between parents and offspring and interactions between brood parasites and their hosts.
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The effect of nest quality for breeding success in Great Reed Warbler
Jelínek, Václav ; Procházka, Petr (advisor) ; Fuchs, Roman (referee)
Nests are key structures for the reproduction of majority of avian species and as such they should be subject to natural selection. Six hypotheses have been suggested to explain variance in avian nest size. In my master thesis I evaluate their validity in the Great Reed Warbler (Acrocephalus arundinaceus). First two hypotheses describe responses of nest size to predation and brood parasitism. These two selection pressures may lead to the reduction of nest size, but no evidence of their impact on nest dimensions was obtained. However, I found a significant but negative relationship between the probability of nest predation and soft nest height. No such relationship was found between the probability of brood parasitism and nest size characteristics. The incidence of brood parasitism was affected only by nest visibility from the nearest cuckoo perch site and distance from open water. More visible nests suffered heavier parasitism while those located deeper in reed beds were better protected from cuckoo parasitism. Another four hypotheses describe selection pressures which favour large nests or some of their functional parts. The thermoregulatory hypothesis, the sexual display hypothesis and the nest support hypothesis did not explain nest size variation. I found support for the clutch size hypothesis,...
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Alternative reproductive strategies and sexual selection in barn swallow Hirundo rustica
Michálková, Romana ; Albrecht, Tomáš (advisor) ; Sedláček, Ondřej (referee) ; Svobodová, Jana (referee)
Molecular techniques have revealed that avian mating system is more diverse and complex than previously thought. Both males and females can use alternative reproductive tactics to increase their fitness. Here, we have determined the prevalence of conspecific brood parasitism (CBP, 22% of nests), quasi-parasitism (QP, 6.5% of nests) and extra-pair paternity (EPP, 51.2% of nests) in European subspecies of barn swallow (Hirundo rustica rustica). In contrast to EPP and CBP, QP is rare and has been described in only a few bird species. Our data indicate nonrandom QP patterns, suggesting that this tactic can be considered a third alternative reproductive strategy, alongside CBP and EPP. Sexual ornaments are usually assumed to evolve as condition-dependent signals of individual quality. In this context, a positive correlation between the expression of ornamental traits and survival, is expected. Evolutionary theory predicts that females seek extra-pair fertilizations from high-quality (more ornamented) males and EPP has consequently been proposed as a principal protagonist in the evolution of male secondary sexual traits, however empirical evidence in support of the assertion is relatively scarce. Despite decades of research into the role of EPP in sexual selection, the potential fitness advantages for...
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Conspecific brood parasitism: a case study on the common pochard and the barn swallow
Petrželková, Adéla ; Hořák, David (advisor) ; Musil, Petr (referee) ; Guillemain, Matthieu (referee)
Presented thesis is mainly concerned with the conspecific brood parasitism (CBP) in birds. CBP is an alternative reproductive strategy when a parasitic female lay egg or eggs to other (host) female's nest of the same species. Then the parasitic female leaves the host's nest and does not provide any energetic investment in a subsequent parental care. Distinguish parasitic eggs or young is problematic because there are no obvious morphological differences. Thus, the use of molecular method is crucial for proper determination of CBP. CBP can be used as 'a best-of-bad-job' when female does not have her own nest or lost her nest for example through predation. Other option is that female can increase her fecundity ('fecundity enhancement' hypothesis) when she lay parasitic egg/eggs and care about her own clutch afterward. Two different model species were studied. The first one was a precocial diving duck - the common pochard (Aythya ferina; Anseriformes; Anatidae). Protein fingerprinting was used for detection of CBP and for distinguishing between eggs of individual females. It was found that the rate of CBP was relatively high in this species (91%, 72%; Chapter 1, 4). Further results indicated that the host clutch size decreased with the number of parasitic eggs in the clutch. The study of individual...
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Visual cues in the coevolution of brood parasite and its hosts
Šulc, Michal ; Honza, Marcel (advisor) ; Fuchs, Roman (referee) ; Samaš, Peter (referee)
Avian brood parasitism is an ideal system for the study of coevolution. Brood parasites and their hosts have developed interesting adaptations during co-evolution allowing them to maximize their fitness. The evolution of these adaptations has a character of an "arms race" where the evolution of one trait in the host is tied with the evolution of another trait in the parasite. In my doctoral thesis, I deal with two of these adaptations: recognition of parasitic eggs by hosts and mimicry of eggs in parasites. Since both these adaptations are influenced by birds' visual system, in all my studies I used an objective method to measure the colour and the modelling of avian visual system that is quite different from the human visual system. For instance, humans in contrast to birds cannot perceive ultraviolet (UV) light. However, this part of spectrum influences behaviour of birds substantially (e.g. courtship or foraging). We found that the hosts of brood parasites can use UV light when recognizing parasitic eggs. However, it seems that this part of spectrum is not the main cue in egg recognition (manuscript 1). Ambient light has also an important impact on colour perception. We determined whether the light conditions in nests influence host responses to alien eggs. The Red Bishop (Euplectes orix) was an ideal...
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Population dynamics of Red-crested Pochard (Netta rufina)
Poláková, Klára ; Musil, Petr (advisor) ; Storch, David (referee)
This study is aimed at analysis of long-term and short-term changes in numbers of Red-crested Pochard (Netta rufina) in Třeboň region. This species is increasing in long-term period and it is also spreading into new localities in the Czech Republic. There were recorded two waves of arrival of Red-crested Pochard arrive, i.e. in April and in May. The total numbers were decreasing at the end of breeding season (from the beginning of July) in study area. The water surface area and area of littoral vegetation were found to be the most important factors affecting preference of individual ponds in pre-breeding season. Furthermore, water transparency seems to be important factor affecting numbers of broods, ducklings and adults in post-breeding season. Low numbers of broods per 1 female were recorded in years with high numbers of Red- crested Pochard at the start of breeding season. However, the frequency of brood parasitism was higher in these years. Key words: Netta rufina, Red-crested Pochard, population dynamics, ducks, breeding, numbers, brood parasitism, south Bohemia
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