|
|
Habitat selection by dragonflies - effect of littoral and riparian vegetation
Bonková, Anita ; Černý, Martin (advisor) ; Waldhauser, Martin (referee)
Dragonflies form one of the important pillars of most aquatic ecosystems and play an important role in maintaining their balance. The main goal of this bachelor's thesis is to summarize current knowledge about the habitat preferences of members of the order Odonata, with a focus on the effect of littoral and riparian vegetation, which are critical components of aquatic biotopes and significantly influence the distribution, abundance and reproductive success of dragonflies. In my work, I focus on all developmental stages, from larvae to adults. These findings are important for the maintenance and revitalization of freshwater ecosystems, in which it is necessary to pay attention to the composition of littoral and riparian vegetation to support the diverse needs of this unique insect order. Key words: habitat preference, dragonflies, Odonata, riparian vegetation, littoral vegetation
|
|
|
Crypsis at dragonflies
Záhorová, Kristýna ; Černý, Martin (advisor) ; Hadrava, Jiří (referee)
Crypsis is one of the defens mechanisms used by animals to hide from predators. It is a form of coloring that allows prey to blend in with their surroundings or makes difficult for predators to see them due to disruptive coloration. Dragonflies utilize crypsis across different families and sometimes even within individual species in various types of environments, ranging from savannas to tropical rainforests. Crypsis also serves as a defense mechanism not only against predators, but also against members of their own species, where females avoid sexual harassment from males and young males avoid fighting with adult males. This is related to changes in coloration during ontogenetic development, as well as the sometimes pronounced sexual dimorphism that is relatively common in dragonflies. Additionally, larvae of dragonflies are often cryptically colored. This study focuses on cryptically colored dragonflies from around the world and in various types of environments. Rather unexpectedly there are not many studies focing on this phenomena at otherwise throroughly studied group of insects. Key words: dragonflies, crypsis, cryptic coloration, sexual dimorphism, dragonflies larvae
|
|
|
Dragonflies (Odonata) of selected localities around Benešov
ŘÍHOVÁ, Radka
This bachelor thesis aimed to map the presence of dragonflies (Odonata) in selected locations around the municipalities of Heřmaničky, Velké Heřmanice, and Mrákotice in Benešovsko. This Bachelor thesis is based on pre-conducted field research (dragonfly capture and observation). Another aim of this bachelor thesis was to investigate the natural conditions at eight pre-selected locations in Benešovsko, compare the sites with each other based on environmental characteristics, and find out the presence of dragonfly communities. It has made the suggestion even about didactic use in primary school teaching.
|
guest ::
