|
|
Incubation effort in Common Pochard and its determinants
Drekslerová, Šárka ; Hořák, David (advisor) ; Musil, Petr (referee)
Incubation of avian eggs is an energy demanding process. Incubating parent faces a conflict between investment into optimal thermal conditions for developig embryos and meeting of own energy requirements. This applies especially in uniparental incubators such as ducks. During incubation, female utilizes energy from fat storage or actual food intake. The proportion of energy used from food than may reflect the time spent by female on the nest. The utilizing of these both sources ratio plays a role in time spent on nest. The aim of the thesis was to describe an incubation rhythm in females of Common Pochard (Aythya ferina) and relate them to climatic variables and changes in body mass. Data were collecetd for three years in the Poodříí Landscape Protected Area at free-living females. We placed a weighting mechanism under the nest with conected datalogger recording voltage variations, which offered me an information about female body mass and time and duration of recesses. Incubation rhytm of females was described by time spent on time ("incubation constancy"), recess frequency and recess duration. Females left the nest most grequently at night-time and during dawn and dusk. Probable explanation of this pattern is better food availability in the night-time and lower risk of nest predation by predators...
|
|
|
Brood parasitism in Common Pochard - a proteomic analysis
Petrželková, Adéla ; Hořák, David (advisor) ; Piálková, Radka (referee)
Conspecific brood parasitism (CBP) is a situation, when female (a parasite) lays egg or eggs in a nest of other conspecific female (a host). Then she leaves the nest and doesn't provide any subsequent parental care, such incubation and care for young. To distinguish between parasitic and host egg or young could be difficult, because there are not obvious morphological differences. CBP was documented in more than 234 species and its frequency is different between species, but also between population of the same species. The main aim of my master thesis was to describe the degree of parasitism in two population of Common Pochard (Aythya ferina). The field work was carried out from 2004-2006 in Třeboň Biosphere Reserve and form 2008-2010 in Poodří Landscape Protected Area. We found that the degree of CBP is relatively high. In Třeboň was found 72 % (41) of parasitized nests and 32 % (165) of parasitic eggs and in Poodří 93 % (39) of parasitized nests and 37 % (153) of parasitic eggs. The mean number of eggs per clutch was around 9 and mean number of host eggs per clutch was 6 in Třeboň. The mean number of eggs per clutch in Poodří was about 10, and the mean number of host eggs was also about 6. The mean number of parasitic eggs per clutch was 3 resp. 4. It was also found, that parasitized nests are...
|
|
|
Incubation effort in Common Pochard and its determinants
Drekslerová, Šárka ; Hořák, David (advisor) ; Musil, Petr (referee)
Incubation of avian eggs is an energy demanding process. Incubating parent faces a conflict between investment into optimal thermal conditions for developig embryos and meeting of own energy requirements. This applies especially in uniparental incubators such as ducks. During incubation, female utilizes energy from fat storage or actual food intake. The proportion of energy used from food than may reflect the time spent by female on the nest. The utilizing of these both sources ratio plays a role in time spent on nest. The aim of the thesis was to describe an incubation rhythm in females of Common Pochard (Aythya ferina) and relate them to climatic variables and changes in body mass. Data were collecetd for three years in the Poodříí Landscape Protected Area at free-living females. We placed a weighting mechanism under the nest with conected datalogger recording voltage variations, which offered me an information about female body mass and time and duration of recesses. Incubation rhytm of females was described by time spent on time ("incubation constancy"), recess frequency and recess duration. Females left the nest most grequently at night-time and during dawn and dusk. Probable explanation of this pattern is better food availability in the night-time and lower risk of nest predation by predators...
|
|
|
Brood parasitism in Common Pochard - a proteomic analysis
Petrželková, Adéla ; Hořák, David (advisor) ; Piálková, Radka (referee)
Conspecific brood parasitism (CBP) is a situation, when female (a parasite) lays egg or eggs in a nest of other conspecific female (a host). Then she leaves the nest and doesn't provide any subsequent parental care, such incubation and care for young. To distinguish between parasitic and host egg or young could be difficult, because there are not obvious morphological differences. CBP was documented in more than 234 species and its frequency is different between species, but also between population of the same species. The main aim of my master thesis was to describe the degree of parasitism in two population of Common Pochard (Aythya ferina). The field work was carried out from 2004-2006 in Třeboň Biosphere Reserve and form 2008-2010 in Poodří Landscape Protected Area. We found that the degree of CBP is relatively high. In Třeboň was found 72 % (41) of parasitized nests and 32 % (165) of parasitic eggs and in Poodří 93 % (39) of parasitized nests and 37 % (153) of parasitic eggs. The mean number of eggs per clutch was around 9 and mean number of host eggs per clutch was 6 in Třeboň. The mean number of eggs per clutch in Poodří was about 10, and the mean number of host eggs was also about 6. The mean number of parasitic eggs per clutch was 3 resp. 4. It was also found, that parasitized nests are...
|
|
| |
guest ::
