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Simple Summary: Myrmecophilous butterflies are highly specialized insects that depend on specific ant species in their habitat to complete their life cycle. The present study was triggered by the drastic decrease in the population size of a myrmecophilous butterfly Scarce large blue (Phengaris teleius) between the years 2008 and 2012 in Ljubljansko barje in Slovenia. Our initial hypothesis was that the extensive and long-lasting flood in the fall of 2010 eradicated host ant species and consequently also decimated the P. teleius population. To test our hypothesis, we conducted spatial analyses that included the current distribution of Myrmica scabrinodis ant species, the extent and duration of three major floods since 2008, the distance from the nearest refuge for ants, and the areas where P. teleius was present in 2008 as an indicator of the presence of the host ant species at that time. We showed that prolonged flooding eradicated ant colonies in flooded meadows. In addition, we calculated the rate of recolonization to be approximately 29 m per year, which compensates for 1.8 days of inundation. Extensively used wet meadows with high species diversity are under threat in Europe by anthropogenic pressure. The increasing frequency of prolonged flooding is emerging as an additional threat to this fragile environment. In our study, we investigated how prolonged flooding affects the spatial distribution and temporal dynamics (through mortality and recolonization process) of the host ant species Myrmica scabrinodis, which is essential for the survival of the endangered Scarce large blue (Phengaris teleius). The study was conducted in the flood-prone Ljubljansko barje plain situated on the southern edge of the species' global range. Prolonged flooding in the study area, possibly affecting the past and current distribution of the host ant M. scabrinodis, was recorded in 2010, 2013, and 2017. In 2020, we set 160 ant traps to estimate the distribution of host ants in a system of meadows covering the entire gradient of flood history. Results indicate that M. scabrinodis survives the flooding for up to three days, starting to disappear if flooding persists longer. After the flooding recedes, ants gradually recolonize empty habitats from the surrounding upland refugia. Our spatial analyses predict that the average recolonization speed was about 29 m per year and that in a year, ants compensate for the mortality effects of 1.8 days of flooding by recolonization in a year. These results show that flooding should be considered as an additional (in some areas, a major) threat to the endangered P. teleius through its deleterious effects on the host ant species. [ABSTRACT FROM AUTHOR]

Artificial feeding is a widely used management tool, but it often attracts nontarget species, including birds, to permanent feeding sites. This study used camera traps to monitor the presence of birds at selected sites used for bear management in Dinaric forest. A large number of bird species (35) were recorded, representing roughly half of all species breeding in the surrounding area. These species were grouped based on monthly and hourly presence, and corresponded to food groups, with most belonging to granivores or scavengers. Some species, such as Pigeons (Columba sp.), Raven (Corvus corax) and Buzzard (Buteo buteo), adapted their presence to the availability of food at the feeding sites, while others were not affected by this. Both Chaffinches (Fringilla coelebs) and Jays (Garrulus glandarius) frequented the feeding sites, but their temporal presence was influenced by their biology rather than by food availability. The Sparrowhawk (Accipiter nisus) also adapted its presence to food availability, and its presence was closely associated with that of the Jay. This study confirms the temporal differences in the use of feeding sites by birds and mammals, which is likely due to their different biology and past management. This can be used to make wildlife management more efficient and reduce the undesirable effects of artificial feeding. [ABSTRACT FROM AUTHOR]

Simple Summary: Wildlife disease surveillance can be considered an essential tool for providing important information about the health status of the population and for protecting human health. Between 2000 and 2020, 284 chamois carcasses from the entire home range of the species in Slovenia were examined using comprehensive necropsy and other laboratory tests. The results indicate a wide range of chamois diseases, but none of the identified diseases can be considered a significant health threat to other wildlife species and/or to humans. In this paper, we provide an overview of the causes of death of Alpine chamois (Rupicapra r. rupicapra) diagnosed in the national passive health surveillance of chamois in Slovenia. From 2000 to 2020, 284 free-ranging chamois provided by hunters were necropsied at the Veterinary Faculty, University of Ljubljana, Slovenia. Depending on the results of complete necropsy, histopathological, bacteriological, parasitological, and virological examinations, a descriptive data analysis was performed. The most common causes of death in chamois were infectious diseases (82.2%), followed by non-infectious diseases (11.8%). Of all the causes of death, parasitic infections accounted for 70.3%, trauma for 9.7%, and bacterial infections for 9.3% of all cases. Less common diseases were viral infections, neoplasms, winter starvation, and metabolic disorders. [ABSTRACT FROM AUTHOR]

Copyright of Gozdarski Vestnik is the property of Federation of Forestry Associations of Slovenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In human-dominated landscapes throughout the world, wildlife seek out anthropogenic foods because they are high in nutritional value and are consistently available. To investigate this mode of foraging, some researchers use stable isotope analysis to detect these animals in populations and estimate their individual diets. In this study, we develop an integrative approach to measure the proportion of corn, a C4 plant, in the diets of free-ranging mammalian omnivores in C3-dominated ecosystems. We fed captive mice corn, C3 plants, and meat until carbon stable isotopes (δ 13C) from each diet equilibrated in their hair. We then used carbon discrimination factors (Δ 13C; offsets between stable isotope values of consumer tissues and their foods) for mice from these feeding trials and a simple carbon stable isotope mixing model to estimate the corn-based diets of free-ranging American black bears in Wisconsin and brown bears in Slovenia. We used Δ 13C factors for mice to estimate the diets of bears because mouse models are used commonly to study mammalian diet and health, including humans and bears, and body mass has no effect on carbon discrimination factors in monogastric mammalian omnivores. In this study, we found that mice grew fastest, largest, and δ 13C values equilibrated quickest in the hair of mice fed meat versus plant-based diets, suggesting protein quantity (quality was the same) has an effect on Δ 13C. Evidence also suggests that Δ 13C did not increase with animal growth rate as all mice grew throughout the 109-day feeding trials, but isotopic equilibration occurred early while mice still were subadults and was maintained throughout their adult lives. We also found that Δ 13C was highest and most variable in the hair, serum, and liver, of mice fed a mixed diet of C3 plants, supporting our mixed diet hypothesis that states that Δ 13C varies more among tissues of animals fed mixed diets than animals fed nonmixed diets because the former are composed of multiple foods, each with different macromolecular and isotopic compositions. Lastly, we found that corn may have been a more important component of bear diets in Wisconsin than previously thought (adults: x ¯ = 29%; x ¯ = 33%; subadults: x ¯ = 22%; x ¯ = 28%), and male brown bears may have fed on 50% more corn (⁠ x ¯ = 47% versus 31%) in autumn during a year when beechnut availability was low. In a world that is rapidly changing, it is more important than ever to develop the appropriate quantitative tools to measure the impact people have on wildlife. Here, we provide such a tool for monogastric mammalian omnivores and encourage other researchers to do the same for other taxa of interest. [ABSTRACT FROM AUTHOR]

Copyright of Gozdarski Vestnik is the property of Federation of Forestry Associations of Slovenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Distribution, quantity and quality of food resources affect the diet and several other life-history traits of large mammals. Supplemental feeding of wildlife has high potential for influencing the behaviour and diet of opportunistic omnivores, such as bears. Supplemental feeding of brown bears Ursus arctos is a common practice in several European countries, but the effects of this controversial and expensive management measure on bear diet and behaviour are poorly understood. We analysed 714 brown bear scats collected throughout the year in three regions of Slovenia with different densities of supplemental feeding sites. Supplemental food was the most important food category in the bear diet and represented 34% of the annual estimated dietary energy content (maize: 22%, livestock carrion: 12%). The proportion of supplemental food in the diet varied with season and region, being highest in spring and in the region with the highest density of feeding sites. However, considerable seasonal changes in bear diet, despite year-round access to supplemental food, suggest that bears prefer high-energy natural food sources, particularly insects, fruits, and hard mast, when available. Despite high availability and use of supplemental food, human-bear conflicts are frequent in Slovenia. In addition, evidence from earlier studies suggests that changes in diet and foraging behaviour due to supplemental feeding may affect several aspects of bear biology and in some cases increase the probability of human-bear conflicts. Thus, we caution against promoting unconditional supplemental feeding as a measure to prevent or reduce human-bear conflicts. [ABSTRACT FROM AUTHOR]

Solid understanding of species' range and local population densities is important for successful wildlife management and research. Specific behavioral and ecological characteristics make brown bear Ursus arctos a difficult species to study. We present a map of range and local population densities of brown bears in Slovenia, made with the use of a new approach similar to voting classifications based on a combination of four datasets: Global Positioning System telemetry data, records of bear removals, systematic and opportunistic direct observations and signs of bear presence, and noninvasive genetic samples. Results indicate that the majority of bears in Slovenia live in Dinaric Mountains in the southern part of the country where local bear population densities exceed 40 bears/100 km. This is one of the highest population densities reported so far for this species worldwide. Population densities decrease towards the north (Alpine region) and are very low along the border with Italy and Austria where almost no females are present. This explains slow past and present expansion of this transboundary bear population into the Alps and should be considered in future bear re-colonization management strategies. Results also showed that data from observations and removals overestimate bear population densities at low values, while mortality and genetic data overestimate population densities in areas with more people. Nevertheless, all data types appeared useful for describing the general bear distribution patterns. Similar approach could be applied to studies of other charismatic or game species, for which several types of data are often available. [ABSTRACT FROM AUTHOR]

Most studies on the relationship between home-range size and composition focus on natural factors, whereas effects of anthropogenic factors are poorly understood. I evaluated effects of multiple natural and anthropogenic habitat factors, population density, and sex on the annual home-range size of red deer (Cervus elaphus) in well-preserved forest areas in the Dinaric Mountains of Slovenia, Europe, based on > 11,000 telemetry locations from 17 males and 25 females. Home ranges were 90-2,107 ha and averaged 460 ha. Using a mixed linear model, I estimated that home-range size decreased with increasing 1) red deer density, 2) supplemental feeding intensity, and 3) average annual temperature; 4) home-range size increased as the distance of main roads from the edge of the home range increased; and 5) males had a larger home range than females (580 ha versus 400 ha). These results were explained by effects of food availability (1, 2, and 3), energy expenditure of an individual (4 and 5), intraspecific interactions (1 and 5), and size of unfragmented habitat patches (4) on home-range size. To my knowledge, this is the 1st large mammal study to explicitly show that the density and spatial distribution of roads and supplemental feeding affect home-range size of red deer and that humans can have a greater impact on home-range size and shape than natural habitat factors. Ungulates are often supplementally fed to increase their value to hunters and to reduce forest damage, particularly in Europe; however, this practice can greatly reduce the home-range size, potentially leading to increased disease transmission and competition associated with the higher deer densities around feeding sites, which can result in just the opposite of what was intended. [ABSTRACT FROM AUTHOR]

Although the brown bear (Ursus arctos) is generally classified as an endangered species, the size and range of several bear populations are increasing in different parts of the world. Understanding how this occurs is essential for the species' management. Using reliable signs of bear presence and models, we analyzed multiple aspects of the spatial expansion of the brown bear population in Slovenia from the Core Bear Protective Area (an area established in 1966 for the conservation of brown bears; hereafter, Core Area) toward the Alps and other parts of the country in 1945-1995. Bear population densities increased between 1945 and 1995, but densities decreased with distance from the Core Area. The observed proportion of females increased overall during the study period from 6% to 20%, but decreased with distance from the Core Area from 27% (0-10 km from the Core Area) to 5% (>70 km from the Core Area). This pattern likely is a consequence of male-biased dispersal, which can cause substantial changes in the sex structure of peripheral parts of populations in space and time. The population showed a net annual growth rate of 1.7%, and expanded spatially at an average rate of 1.6-1.9 km/year. Some females were recorded far from the Core Area (>80 km), suggesting that unlike in stable or declining populations, females in expanding populations can exhibit long-distance dispersal. However, the frequency of females that dispersed far was so small that it probably had little impact on the dynamics of the population expansion. [ABSTRACT FROM AUTHOR]

In this paper, we address three aspects of the brown bear population in Slovenia: its size (and its evolution over time), its spatial expansion out of the core area, and its potential habitat based on natural habitat suitability. Data collected through measurement/observation of the bear population and from the literature are used. A model is developed for each aspect. The results are estimates of population size, a picture of the spatial expansion of the population and maps of its optimal and maximal potential habitat (based on natural suitability). Overall, the brown bear population has been increasing since the establishment of a core protective area and has been expanding outside this area. The habitat suitability maps show that there is room for further expansion. Based on habitat suitability and bear population density, as well as human activity and current damage reports, we recommend that the Alps should be temporarily kept free of the bears, until the necessary mitigation measures regarding human–bear conflicts are carried out. On the other hand it is of crucial importance to adapt human activities and improve bear management in the optimal habitat, with which the goals of successful conservation of the species might be achieved. [Copyright &y& Elsevier]

Simple Summary: Wildlife can serve as a reservoir for highly contagious and deadly diseases, many of which are infectious to domestic animals and/or humans. Wildlife pathogen and disease surveillance is, thus, an essential tool that can provide valuable information on population health status and protect human health. Blood samples from 244 wild animals and 5 from carcasses were tested for specific antibodies against Leptospira serovars in Slovenia between 2019 and 2020 using the microscopic agglutination test. The results confirm that various wildlife species were exposed to Leptospira interrogans and may be used as a sentinel for leptospirosis, which is considered a significant health threat to other wildlife species and to humans. A total of 249 serum samples from 13 wild animal species namely fallow deer (Dama dama, n = 1), roe deer (Capreolus capreolus, n = 80), red deer (Cervus elaphus, n = 22), chamois (Rupicapra rupicapra, n = 21), mouflon (Ovis musimon, n = 4), brown hare (Lepus europaeus, n = 2), nutria (Myocastor coypus, n = 1), red fox (Vulpes vulpes, n = 97), stone marten (Martes foina, n = 12), European badger (Meles meles, n = 2), golden jackal (Canis aureus, n = 2) Eurasian lynx (Lynx lynx, n = 2) and grey wolf (Canis lupus, n = 3) were analysed for the presence of antibodies against Leptospira interrogans sensu stricto. Serum samples were examined via the microscopic agglutination test for the presence of specific antibodies against Leptospira serovars Icterohaemorrhagiae, Bratislava, Pomona, Grippotyphosa, Hardjo, Sejroe, Australis, Autumnalis, Canicola, Saxkoebing and Tarassovi. Antibodies to at least one of the pathogenic serovars were detected in 77 (30.9%; CI = 25–37%) sera. The proportion of positive samples varied intraspecifically and was the biggest in large carnivores (lynx, wolf and jackal; 86%), followed by mezzo predators: stone marten (67%) and red fox (34%), and large herbivores: red deer (32%), roe deer (25%), alpine chamois (10%) and mouflon (0%). Out of the 77 positive samples, 42 samples (53.8%) had positive titres against a single serovar, while 35 (45.4%) samples had positive titres against two or more serovars. The most frequently detected antibodies were those against the serovar Icterohaemorrhagiae. The present study confirmed the presence of multiple pathogenic serovars in wildlife throughout Slovenia. It can be concluded that wild animals are reservoirs for at least some of the leptospiral serovars and are a potential source of leptospirosis for other wild and domestic animals, as well as for humans. [ABSTRACT FROM AUTHOR]

Simple Summary: Wildlife can serve as a reservoir for highly contagious and deadly diseases, many of which are infectious to domestic animals and/or humans. Wildlife disease surveillance can be considered an essential tool to provide important information on the health status of the population and for the protection of human health. Between 2000 and 2019, examinations of 510 roe deer carcasses were conducted by comprehensive necropsy and other laboratory tests. In conclusion, the results of this research indicate a broad spectrum of roe deer diseases, but no identified disease can be considered a significant health threat to other wildlife species and/or to humans. In this paper, we provide an overview of the causes of death of roe deer (Capreolus capreolus) diagnosed within the national passive health surveillance of roe deer in Slovenia. From 2000 to 2019, postmortem examinations of 510 free-ranging roe deer provided by hunters were conducted at the Veterinary Faculty, Slovenia. A comprehensive necropsy was performed. According to the results of the necropsy, the samples were subjected to microscopic, histopathological, bacteriological, parasitological, or virological examination. The most frequent causes of death in roe deer were infectious diseases (67%), followed by noninfectious diseases (28%). Of all deaths, parasitic infections represented 48%, bacterial infections 14.8%, trauma 12.5%, and metabolic disorders 9.8%. Less frequent causes were diseases like neoplasia and mycotic infections, winter starvation, hernias, and lightning strike. This study covered an estimated 1% of the total disease-related mortality of roe deer in Slovenia. Comparisons of sex/age structure indicated that hunters did not provide random samples (e.g., young males were disproportionately represented). Therefore, such monitoring does not ensure an unbiased assessment of the significance of the individual disease for the mortality of the population; however, it can provide credible evidence of whether or not a particular disease is present in a population. We show that no identified disease in roe deer in Slovenia can be considered a significant health threat to roe deer, other wildlife species, or humans. [ABSTRACT FROM AUTHOR]

Isotope diet-tissue discrimination factors can significantly influence dietary proportions estimated with stable isotope mixing models. For bears, for which discrimination factors from controlled dietary experiments are currently lacking for most tissues and diets, literature reports 3 approaches have so far been used to compile carbon and nitrogen discrimination factors, and recently one additional approach has been proposed. We used these 4 approaches to compile carbon and nitrogen discrimination factors for the brown bear (Ursus arctos) population in Slovenia (southeastern Europe). By performing a sensitivity analysis of the stable isotope mixing models, we then tested how these different discrimination factors affected dietary estimates for bears. We found substantial differences in the dietary estimates among the applied approaches, with the approach that uses discrimination factors from different species producing most distinct results. Our results suggested that these differences were more pronounced among approaches with larger differences in discrimination factors and for isotopically less distinct food sources. We show that the 4 approaches can lead to contrasting conclusions about bear diets, which can have important ecological and management consequences. Therefore, when using stable isotope mixing models without experimentally obtained species-, diet-, and tissue-specific discrimination factors, the choice of the discrimination-factor compilation approach is vital. All 4 approaches have limitations that must be considered because they can result in erroneous discrimination factors when certain species, diets, and tissues are used. We review these limitations and provide recommendations about the use of these approaches in stable isotope dietary studies for bears. [ABSTRACT FROM AUTHOR]

Harvesting wild animals can affect demographic parameters and life history traits of surviving individuals. Most brown bear (Ursus arctos) populations currently experience low levels of hunting. We characterized mortality patterns in a heavily exploited transboundary brown bear population in Slovenia, Central Europe. Overall, 927 brown bears were reported removed from 1998 to 2008. Most (97%) removals were human caused including removals from hunting (59% of removals), management removals of problem individuals (18%), and vehicle collisions (16%). Median age of bears removed in Slovenia was 2.3 years, and 78% of bears removed were <4 years old. Removal was male-biased overall (59%), mainly due to the high percent (49%) of young (<4 years old) males removed during hunting, a possible consequence of sex-related differences in bear behavior and harvest regulations. However, the effect of sex-biased removal was less than expected based on removal data, and it appears a different harvest regimen in neighboring Croatia and sex-biased dispersal of young bears buffered the demographic effects of selective harvest in Slovenia. We also observed that annual proportion of females in harvests increased with harvest intensity. More males were removed among younger classes, whereas females started to dominate above the age of 8 years. About 20% of the brown bear population was removed annually by legal harvest; this is one of the highest harvest rates reported for this species. [ABSTRACT FROM AUTHOR]

The effective population size (N(e) ) could be the ideal parameter for monitoring populations of conservation concern as it conveniently summarizes both the evolutionary potential of the population and its sensitivity to genetic stochasticity. However, tracing its change through time is difficult in natural populations. We applied four new methods for estimating N(e) from a single sample of genotypes to trace temporal change in N(e) for bears in the Northern Dinaric Mountains. We genotyped 510 bears using 20 microsatellite loci and determined their age. The samples were organized into cohorts with regard to the year when the animals were born and yearly samples with age categories for every year when they were alive. We used the Estimator by Parentage Assignment (EPA) to directly estimate both N(e) and generation interval for each yearly sample. For cohorts, we estimated the effective number of breeders (N(b) ) using linkage disequilibrium, sibship assignment and approximate Bayesian computation methods and extrapolated these estimates to N(e) using the generation interval. The N(e) estimate by EPA is 276 (183-350 95% CI), meeting the inbreeding-avoidance criterion of N(e) > 50 but short of the long-term minimum viable population goal of N(e) > 500. The results obtained by the other methods are highly consistent with this result, and all indicate a rapid increase in N(e) probably in the late 1990s and early 2000s. The new single-sample approaches to the estimation of N(e) provide efficient means for including N(e) in monitoring frameworks and will be of great importance for future management and conservation., (© 2012 Blackwell Publishing Ltd.)