Wildlife populations in Slovenia are managed through adaptive management whichis based on several biological indicators (e. g. body weight, antler trophy value). It is supposed, that such indicators would respond to the changes in population density, which is not assured. The main purpose of this thesis was to evaluate four potential indicators for use in adaptive management (body weight, trophy value, offspring sex ratio, fertility index). Wildlife data (red- and roe deer) were collected in State hunting reserve withthe special purpose Medved Kočevje, between the period of 1986 to 2012. For the entire period population density estimates, data about environmental factors and indicators were calculated. Indicators were then compared to population densities and environmental factors. The results are based on the assumption that density dynamics of the target species are well estimated. Of the indicators discussed, the offspring sex ratio showed the best correlation with population density in both red- and roe deer population. In addition to the offspring sex ratio, also fawn and yearling red deer body weights are suitable for use as an indicator, even though body weight showed only a weak response to changes in population density. The results showed that the impact of environmental factors on the indicators is very high. This should be taken into account when interpreting the indicators. The strongest influence showed the winter weather, mast years and summer drought. Currently implemented indicators (body weight, trophy value) showed a lower response to estimated density changes as it had been believed before.
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