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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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Breeding site fidelity in waterfowl
Kejzlarová, Tereza ; Musil, Petr (advisor) ; Fuchs, Roman (referee)
The thesis is concerned in breeding site fidelity and focused on Anseriformes, especially Anatidae. Higher fidelity ratio in females than in males is an interesting pattern of breeding site fidelity in this bird group. On the contrary, an opposite pattern, i. e. higher fidelity ratio in males prevailed among other bird species. This study is aimed at describing this phenomenon and discussion of factors affecting fidelity ratio. Among, the most important factors, the importance of the previous breeding success and environmental conditions is underlined. The study includes data about fidelity ratio from 40 studies of breeding site fidelity in Anatidae.
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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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Breeding site fidelity in waterfowl
Kejzlarová, Tereza ; Musil, Petr (advisor) ; Fuchs, Roman (referee)
The thesis is concerned in breeding site fidelity and focused on Anseriformes, especially Anatidae. Higher fidelity ratio in females than in males is an interesting pattern of breeding site fidelity in this bird group. On the contrary, an opposite pattern, i. e. higher fidelity ratio in males prevailed among other bird species. This study is aimed at describing this phenomenon and discussion of factors affecting fidelity ratio. Among, the most important factors, the importance of the previous breeding success and environmental conditions is underlined. The study includes data about fidelity ratio from 40 studies of breeding site fidelity in Anatidae.
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Possible effect of patogens on fttness of selected duck species
Langrová, Anna ; Votýpka, Jan (referee) ; Musil, Petr (advisor)
In total, 76 birds, mainly breeding females, were captured in years 2007-2009. Birds were inspected for the presence of avian influenza (AI) viruses and the AI antibodies. They were inspected as well for the presence of bacteria Borrelia burgdorferi s. l. and Anaplasma phagocytophilum and protozoan Leucocytozoon simondi in blood. The feces were examined for the oocysts and eggs of intestinal parasites. AI viruses were found in 4 cases, while over 80% of inspected birds had AI antibodies. Bacteria B. burgdorferi s. l. and A. phagocytophilum were found in 2 and 1 case respectively. Protozoan L. simondi was not found in any blood smear. The oocysts from protozoan genera Eimeria and Tyzzeria and eggs from roundworm genera Capillaria, Amidostomum and Echinuria were observed in feces. Statistical analyses were due to the small size of our data set inconclusive.
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