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Artificial feeding of wildlife is a widespread, but controversial, management practice with many positive and negative effects. Besides the effects on the target species, it can also affect other (nontarget) species by modulating interspecific interactions. Previous research showed that the presence of artificial feeding sites for bears and ungulates increases the risk of kleptoparasitism by the brown bear (Ursus arctos) on kills made by Eurasian lynx (Lynx lynx). However, it remains unknown whether lynx adjust their behaviour to the distribution of artificial feeding sites, which also attract potential prey (ungulates) for lynx. Using GPS telemetry data, we explored the spatiotemporal lynx response to such sites and studied how this response varied with experience level, i.e. between adult resident individuals (’experienced lynx’) and juveniles and/or translocated individuals (’naïve lynx’). We found that lynx experience played an important role in the use of artificial feeding sites. Specifically, while both experienced and naïve lynx selected feeding sites while moving within their home range, the attraction was stronger among the naïve lynx. Considering the distribution of kill sites, naïve lynx killed prey closer to the artificial feeding sites than expected, while experienced lynx avoided them. Finally, the proximity to artificial feeding sites by experienced lynx showed an annual variation, matching the seasonal kleptoparasitism risk, with overall closer proximity to feeding sites during the winter, when bears are less active, which is also when ungulates are more concentrated around feeding sites. Our study suggests that, despite the relatively recent introduction of artificial feeding in the ecosystems, wildlife can learn to respond to the altered interactions with other species. However, this appears to be a learning process with manifold management and conservation implications. A better understanding of species interactions and space use in the context of resource manipulation is increasingly relevant as the use of anthropogenic food by wildlife is nowadays substantial and widespread across most parts of the world. Nasl. z nasl. zaslona. Opis vira z dne 31. 5. 2023. Bibliografija: str. 10-11. Abstract.

Context Adjustments in habitat use by large carnivores can be a key factor facilitating their coexistence with people in shared landscapes. Landscape composition might be a key factor determining how large carnivores can adapt to occurring alongside humans, yet broad-scale analyses investigating adjustments of habitat use across large gradients of human pressure and landscape composition are lacking. Objectives Here, we investigate adjustments in habitat use by Eurasian lynx (Lynx lynx) in response to varying availability of refuge habitats (i.e., forests and rugged terrain) and human landscape modification. Methods Using a large tracking dataset including 434 individuals from seven populations, we assess functional responses in lynx habitat use across two spatial scales, testing for variation by sex, daytime, and season. Results We found that lynx use refuge habitats more intensively with increasing landscape modification across spatial scales, selecting forests most strongly in otherwise open landscapes and rugged terrain in mountainous regions. Moreover, higher forest availability enabled lynx to place their home ranges in more human-modified landscapes. Human pressure and refuge habitat availability also shaped temporal patterns of lynx habitat use, with lynx increasing refuge habitat use and reducing their use of human-modified areas during periods of high exposure (daytime) or high vulnerability (postnatal period) to human pressure. Conclusions Our findings suggest a remarkable adaptive capacity of lynx towards human pressure and underline the importance of refuge habitats across scales for enabling coexistence between large carnivores and people. More broadly, we highlight that the composition of landscapes determines how large carnivores can adapt to human pressure and thus play an important role shaping large carnivore habitat use and distributions.

Globally, fragmented landscapes and other anthropogenic pressures are causing declines in large carnivore populations. Conservation organizations are working to counteract these trends through the translocations of large carnivores, for example by reintroducing them to their historic ranges or by reinforcing existing populations to promote gene flow and resilience. This study analyses a dataset gathered from 33 translocation projects involving 297 individual animals across 22 countries in five continents, with 18 different large carnivore (>15 kg) species surveyed. An overall success rate (survival > six months) of 66 % for all individuals was shown for large carnivores, indicating an above average success rate when compared to the translocation of other terrestrial vertebrates. While captive-born individuals still fared worse than wild-born individuals, a 32 % increase in success rates was observed for releases of captive-born individuals within the last 14 years compared to a 17 % increase in success for releases of wild-born individuals. Despite the encouraging trends in metrics of success, only 37 % of study individuals were observed engaging in reproductive behavior. While this is likely an under-count, we caution against the conflation of translocation success with population establishment. We also identified key choices in the decision tree facing those implementing translocations, and analyzed associated metrics of success. Critical decisions include whether or not to use soft-releases, choosing younger animals, selecting unfenced release locations, and sourcing wild-born individuals – all of which can lead to a higher likelihood of success. As the UN Decade of Ecosystem Restoration gets underway, we hope this information can assist decision makers and practitioners in achieving more desirable outcomes for conservation translocation of large carnivores. Bibliografija: str. 8-9.

International audience; Sharing space with large carnivores on a human-dominated continent like Europe results in multiple conflictful interactions with human interests, of which depredation on livestock is the most widespread. We conducted an analysis of the impact by all four European large carnivores on sheep farming in 10 European countries, during the period 2010–2015. We ran a hierarchical Simultaneous Autoregressive model, to assess the influence of several ecological factors on the reported depredation levels. About 35,000 (SD = 4110) sheep kills were compensated in the ten countries as caused by large carnivores annually, representing 0.5% of the total sheep stock. Of them, 45% were recognized as killed by wolves, 24% by wolverines, 19% by lynx and 12% by bears. We found a positive relationship between wolf distribution and the number of compensated sheep, but not for the other three species. Depredation levels were lower in the areas where large carnivore presence has been continuous compared to areas where they disappeared and returned in the last 50 years. Our study shows that a few large carnivores can produce high damage, when the contribution of environmental, social, and economic systems predisposes for it, whereas large populations can produce a limited impact when the same components of the system reduce the probability that depredations occur. Time of coexistence plays in favour of a progressive reduction in the associated costs, provided that the responsible agencies focus their attention both on compensation and co-adaptation.

The Eurasian lynx is of special conservation concern based on the European Union's Habitat Directive and its populations need to be maintained or restored at favourable conservation status. To evaluate lynx population status, appropriate monitoring needs to be in place. We modelled the distribution dynamics of lynx in the Alps (200 000 km2) during 1994–2014 at a resolution of 100 km2. Lynx distribution and detection probability varied by year, country, forest cover, elevation and distance to the nearest release site. Occupancy of neighbouring quadrats had a strong positive effect on colonization and persistence rates. Our analyses demonstrate the importance of accounting for imperfect detection: the raw data underestimated the lynx range by 55% on average, depending on country and winter. Over the past 20 years the Alpine lynx range has expanded at an average rate of 4% per year, which was partly due to the lynx translocations to new areas. Our approach to large-scale distribution modelling and analysing trends using site occupancy models can be applied retrospectively and is useful in many cases where a network of trained people is established to report the presence of target species, for example, in Europe where member states of the European Union have to report conservation status of species of community interest. Hence, dynamic occupancy models are an appealing framework for inference about the large-scale range dynamics based on opportunistic data and a useful tool for large-scale management and conservation programmes.

As large carnivores recover throughout Europe, their distribution needs to be studied to determine their conservation status and assess the potential for human-carnivore conflicts. However, efficient monitoring of many large carnivore species is challenging due to their rarity, elusive behavior, and large home ranges. Their monitoring can include opportunistic sightings from citizens in addition to designed surveys. Two types of detection errors may occur in such monitoring schemes: false negatives and false positives. False-negative detections can be accounted for in species distribution models (SDMs) that deal with imperfect detection. False-positive detections, due to species misidentification, have rarely been accounted for in SDMs. Generally, researchers use ad hoc data-filtering methods to discard ambiguous observations prior to analysis. These practices may discard valuable ecological information on the distribution of a species. We investigated the costs and benefits of including data types that may include false positives rather than discarding them for SDMs of large carnivores. We used a dynamic occupancy model that simultaneously accounts for false negatives and positives to jointly analyze data that included both unambiguous detections and ambiguous detections. We used simulations to compare the performances of our model with a model fitted on unambiguous data only. We tested the 2 models in 4 scenarios in which parameters that control false-positive detections and true detections varied. We applied our model to data from the monitoring of the Eurasian lynx (Lynx lynx) in the European Alps. The addition of ambiguous detections increased the precision of parameter estimates. For the Eurasian lynx, incorporating ambiguous detections produced more precise estimates of the ecological parameters and revealed additional occupied sites in areas where the species is likely expanding. Overall, we found that ambiguous data should be considered when studying the distribution of large carnivores through the use of dynamic occupancy models that account for misidentification.