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The importance of water sources for space-use of mammals in African savannah
Homoláč, David ; Hořák, David (advisor) ; Brandlová, Karolína (referee)
African savannas are seasonal ecosystems experiencing a significant dry period each year. During the dry season, water scarcity has both, spatial and temporal consequences on the movements of large mammals. Some mammals can cope with these resource restrictions better than others. These water independent mammals predominantly feed on browse (giraffe, kudu, eland) and can be found further from water sources. However, these mammals can utilize areas near rivers as these areas provide food resources. Water dependent species are predominantly grazers and non-ruminants (zebra, wildebeest, elephant). Water shortage during a dry season restricts the movements of these species, which can be generally found in the vicinity of water bodies. Carnivore species (lions) react on the spatial restrictions of ungulates by adjusting their hunting areas to the vicinity of water sources. Both intra-guild (African wild dog) and inter-gild prey species (ungulates) develop anti-predatory strategies such as temporal and spatial segregation. African wild dogs use dens far from water points and ungulate species use to drink during daytime when lions are not active. Spatial and temporal segregation are also strategies to cope with competitors. Daily patterns of water point visitations can vary suggesting other factors...
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Growth of ungulates
Gašparová, Kateřina ; Brandlová, Karolína (advisor) ; Barbora, Barbora (referee)
The bachelor thesis deals with the growth of giraffes (Giraffa camelopardalis). From the data obtained from scientific publications, I examined whether there are differences in size between wild and captive giraffes. I also evaluated the size differences between subspecies and I examined whether the data in encyclopedias correspond to
the information published in scientific journals. For lack of data about the height I assessed only weight.
I put data from scientific publications into spreadsheet and I further analyzed this obtained data. Due to sexual dimorphism, the results were analyzed separately for males and females.
For both sexes, individuals living in the wild are significantly heavier than individuals living in captive. Smaller body weight of captive individuals may be due
to unnatural diet and climate. So it is with birth weight of calves, in the wild, calves are born heavier.
In case of weight differences among subspecies, there are significant differences among females. The results may be connected with clinal changes known from other mammals or they may be influenced by non-balanced number of individual data within the subspecies.
We can say that the information in encyclopedias do not correspond with scientific articles, at least in terms of weight. In encyclopedias there are probably the record values, not the average one.
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