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Free-ranging large herbivores are keystone species in terrestrial ecosystems, and have an important ecological role by affecting both the structure and the function of plant communities and other groups of organisms. Large herbivores often increase plant diversity especially in more productive grasslands such as temperate grasslands in Europe. Additionally, other important effects of ruminants are redistribution of nutrients by feeding and subsequent excretion of urine and dung, soil compaction and erosion via trampling and dispersal of seeds, respectively. In Europe, populations of several ruminants species are increasing both in number and geographical distribution, and problems connected with effects of grazing of red deer (Cervus elaphus L.) on grassland in some locations in Slovenia have been increasing as well. Several areas of the Inner Carniola and Kočevje regions have been overgrown with forest, and these areas have the highest density of red deer. Therefore, the pressure of red deer on the remaining grasslands is increasing and may cause important economic loss for land owners. Ungulates can affect the economic profitability of grasslands also indirectly, through the impact on species composition of grasslands and by altering the overall productivity of soil. For proper management of their populations both direct and indirect ecological impacts and value of free-ranging ungulates have to be known. Therefore, an overview of foreign and Slovene studies related to the impacts of free-ranging ruminants on grassland ecosystems is presented in the paper.

To check the reliability of macroscopic (ocular) assessment of the age of red deer (Cervus elaphus L.) obtained by ocular inspection of teeth eruption and wear (done by hunters or hunter commissions), a validation of the precision of these assessments was carried out on a representative sample set, i.e. a total 2008-annual cull of red deer in the entire Slovenia. The reliability of ocular age assessment test was performed by cutting/grinding of the first mandibular molar (M1) and counting the incremental layers of dental cementum on 821 samples of adults (aged from two to twenty-two years). The ocular age assessment of adult red deer (regardless of sex) was biased with a large error (maximum deviation between both assessments: nine years). With both methods, the same animal age was established in 24.5% of cases, and with the age of the animals the reliability of ocular assessment declined. Ages of hinds and younger stags were both under-assessed and over-assessed; however, ages of older stags were generally over-assessed. Out of 426 analysed stags, 142 (33.3%) were categorized in another age category as found by counting annuli in tooth cementum. This raises doubts about the reliability of the current categorization of adult red deer stags into three age categories (2–4 years old, 5–9 years old, and 10+ years old, respectively); indeed, precise (on a yearly basis) ages of adult stags are impossible to be identified by routine age assessment, such as the inspection of teeth wear

Knowledge of abundance and local densities of deer populations is important inmanagement as well as in biological context. Faecal pellet-group count method, widely used around the world for estimating deer numbers, has been almost neglected in our country. Therefore, we have prepared a comprehensive overview of the method with recommendations for Slovenia to enhance its use. In principle, there are two ways to perform the faecal pellet-group count method, i.e. clearance plot and standing crop method. The latter is not recommended in a daily management practice, as it requires faecal pellet-groupdecay rate estimation, which is rather season and microhabitat specific. Sampling can be done on sampling plots of different shapes and sizesor with the line transect method. Sampling design depends on expected deer densities and ground cover dependent pellet-group detectability. Since distinct habitats are used differentially by the deer, study area stratification on specific habitat types regarding the expected deer densitiesis recommended. Within the species, defecation rates (i.e. number of pellet-groups per day) vary according to season, animal age and gender; nevertheless, due to comparative reasons we recommend the use of constant defecation rates (i.e. 25 for the red deer, 20 for the roe deer, respectively). Moreover, multiple samplings are needed to cover seasonal variety in habitat use. Sampling design is of a major importance for the success of the method and has the biggest impact on the precision of deer numbers/densities estimates, therefore much effort should be devoted to this stage.

Increased concentrations of fluorides in the environment have a negative impact on different animal species, which are manifested mainly with the irregular formation of the dental hard tissue, called dental fluorosis. With the assessment of dental fluorosis in every adult roe deer shot in eastern Slovenia in 10 Hunting Management Districts in 2007 (n = 7,158), implementation of statistical analyses in raster GIS environment with high resolution (1x1 km) and cartography, we wished to: (i) establish the differences in the appearance and distribution of dental fluorosis in roe deer from different areas of eastern Slovenia; (ii) define the impact of the main sources of fluorides on the appearance and distribution of dental fluorosis; (iii) determine the most important environmental factors that have an impact on the appearance of dental fluorosis. In general, eastern Slovenia is not polluted with fluorides, while less than 1% of samples showed moderate to severe dental fluorosis; 84% of samples showed no fluorosis at all. Only in the vicinity of the most important source of fluorides in Slovenia (aluminium smelter), there is an area with extreme fluoride pollution of the environment. The multivariate statistics revealed that the appearance and distribution of dental fluorosis are influenced primarily by: (i) the distance from the most important point source – (94.6% of the total variance); (ii) the age of the analysed animal (5% of the total variance); and (iii) the distance from the nearest forest edge (0.7% of the total variance), respectively

Population size and range of wild boar (Sus scrofa L.) have increased significantly during the past decades in Slovenia, as well as in other European countries. Simultaneously, this has caused an increase in agricultural damages. In this study, we examined the influence of various environmental factors on wild boar spatial distribution, and identified its current and potential population distribution range for Slovenia. The researchis based on a large sample (N = 5.977) of georeferenced locations of boar harvested from the entire country and on GIS data layers (25 environmental variables). Analyses revealed that wild boar densities are highest in areas: (a) with outstanding availability of energy-rich food items (i.e. adult deciduous forests with high hard mast production and supplemental feeding places) and good cover accessibility (i.e. agricultural areas near forests and early successional areas); (b) where the temperatures are high andwinters are mild with low snowfall (the probability of use increases with temperature and decreases with quantity of precipitation). Spatial distribution of wild boar also depends on the percentage of forests and the level of forest fragmentation (i.e. size of forest fragments). Currently, boars inhabit 55% of Slovenia, yet the potential habitat extends up to 67% of the country. The wild boar population size and range are therefore likely to increase, especially if the current trends of environmental changes continue, such as rising temperatures, increased forested area, and a decrease in coniferous trees.