Aim: Large carnivores worldwide have experienced substantial range contractions due to human activities, though several species are recolonising parts of their historical range. We aimed to assess current and potential European brown bear (Ursus arctos arctos) habitat as well as habitat connectivity on a continental scale. Location: The extended biogeographical regions of Europe, spanning from Portugal to central Russia, longitudinally, and from Norway to T & uuml;rkiye, latitudinally. Excluding inland seas; this area covers 11,151,636 km(2). Methods: We assessed habitat suitability throughout the study area using an ensemble species distribution model with nine submodels, using data from 10 European bear populations and T & uuml;rkiye. We used the resulting habitat suitability maps to conduct a least-cost path connectivity analysis and an omnidirectional circuit connectivity analysis. Main Conclusions: Habitat suitability was strongly associated with low percentages of agricultural cover, low percentages of human development, and proximity to forest. Of our entire study area, 37% (4.09 million km(2)) is occupied or potentially suitable for bears. Connectivity analyses identified corridors that could facilitate movement among southern European bear populations, though agricultural land and human development limit connectivity between northern and southern European bear populations. Previous research estimated bears occupied 0.5 million km(2) across the European Union, while our results estimate 1.82 million km(2) of this part of our study area is potentially suitable for bears, though connectivity is limited. Our results inform conservation strategies and policy development for the future of brown bears in Europe, emphasising the need for transboundary conservation efforts.

Reproductive lifespan and age-specific reproductive performance are key life-history traits, shaping individual fitness and population dynamics. Here, we examine age-specific variation in reproductive success in a wild large carnivore, the Eurasian lynx (Lynx lynx), using 38 years of longitudinal data from 173 known-age females across Europe and western Asia. Female lynx exhibited age-related reproductive patterns: (i) breeding probability increased with age before declining at older ages, (ii) litter size remained generally stable at two kittens, although it declined to one kitten in older mothers at northern latitudes, and (iii) offspring survival peaked at intermediate female ages, with variation across individuals, years and latitudes. These patterns likely reflect physiological maturation and increased experience (ages 2 to 8), followed by declines due to reproductive and maternal effect senescence in older females. Temporal and latitudinal variations suggest that environmental conditions shape reproductive patterns in Eurasian lynx, with senescence particularly pronounced in resource-scarce environments. Our findings enhance the understanding of age-related reproductive patterns in carnivores across environmental contexts, contributing to life-history theory and improving evidence-based management by accounting for age structure in population forecasting.

Translocations and reintroductions aim to improve the viability of isolated populations and promote connectivity for large carnivores. However, there is no established framework for assessing their success. We used the Eurasian lynx (Lynx lynx) in western and central Europe to assess the impact of translocations on the viability of six populations and their interconnectivity. Lynx populations are small and isolated and have low genetic diversity. Population reinforcements have been carried out, but their impact has not been determined. We devised a workflow to evaluate how releasing new individuals affects population extinction probability and connectivity and patch colonization, and to estimate the minimum release population to create a stepping-stone network. To this end, we calibrated a spatially explicit, individual-based model with space use, survival, and reproductive rates observed in the populations and validated it with field data on population growth and expansion from the 1970s to 2020. We ran the model with the observed population structure in 1995-1996 to 2040 in two scenarios, with and without translocations. In both scenarios, most existing populations remained stable in our model for the next 20 years, but had low connectivity. Lynx translocations positively affected viability and connectivity on a population scale but did not increase connectivity between the eastern and western Alps. To create a stepping-stone population that would significantly improve connectivity across the Alps, we conservatively estimated that at least 13 males and 37 females should be released in the Italian southeastern Alps based on the assumption of negligible immigration rates between patches. Concerted transboundary management to improve the future survival of lynx populations in western and central Europe is still needed.

Translocations are central to large carnivore restoration efforts, but inadequate monitoring often inhibits effective conservation decision-making. Extinctions, reintroductions, illegal killings, and high inbreeding levels of the Central European populations of Eurasian lynx (Lynx lynx) typify the carnivore conservation challenges in the Anthropocene. Recently, several conservation efforts were initiated to improve the genetic and demographic status but were met with variable success. Here, we report on successful, stakeholder-engaged translocation efforts across three countries aimed to: (1) reinforce the Dinaric lynx population that was suffering from high inbreeding levels and (2) create a new stepping-stone subpopulation in the neighboring Southeastern Alps to help connect the Dinaric and Alpine populations. To evaluate the success of these efforts, we used multidisciplinary and internationally coordinated monitoring using systematic camera trapping, non-invasive genetic sampling, GPS tracking, recording of reproductive events and interspecific interactions, as well as the simultaneous tracking of the public and stakeholders' support of lynx conservation before, during, and after the translocations. Among the 22 translocated wild-caught Carpathian lynx, 68% successfully integrated into the population and local ecosystems, and at least 59% reproduced. The probability of dispersing from the release areas was three times lower with the soft-release method than with hard-release method. Translocated individuals had substantially lower natural mortality and higher reproductive success, while their ecological impact was similar compared to the lynx from the remnant population. Cooperation with local hunters and protected area managers enabled us to conduct multi-year camera-trapping and non-invasive genetic monitoring across a 12,000-km2 transboundary area. Results indicate a reversal in population decline, as the lynx abundance increased for >40% during the 4-year translocation period. Effective inbreeding decreased from 0.32 to 0.08-0.19, suggesting a twofold to fourfold increase in fitness. Furthermore, the successful establishment of a new stepping-stone subpopulation represents an important step toward restoring the Central European lynx metapopulation. Robust partnerships with local communities and hunters, coupled with transparent communication, helped maintain high public and stakeholder support for lynx conservation throughout the translocation efforts. Lessons learned about the importance of stakeholder involvement and multidisciplinary monitoring conducted across several countries provide a successful example for further efforts to restore large carnivores in human-dominated ecosystems.

Biotic interactions are expected to influence species' responses to global changes, but they are rarely considered across broad spatial extents. Abiotic factors are thought to operate at larger spatial scales, while biotic factors, such as species interactions, are considered more important at local scales within communities, in part because of the knowledge gap on species interactions at large spatial scales (i.e., the Eltonian shortfall). We assessed, at a continental scale, (i) the importance of biotic interactions, through food webs, on species distributions, and (ii) how biotic interactions under scenarios of climate and land-use change may affect the distribution of the brown bear (Ursus arctos). We built a highly detailed, spatially dynamic, and empirically sampled food web based on the energy contribution of 276 brown bear food species from different taxa (plants, vertebrates, and invertebrates) and their ensemble habitat models at high resolution across Europe. Then, combining energy contribution and predicted habitat of food species, we modelled energy contribution across space and included these layers within Bayesian-based models of the brown bear distribution in Europe. The inclusion of biotic interactions considerably improved our understanding of brown bear distribution at large (continental) scales compared with Bayesian models including only abiotic factors (climate and land use). Predicted future range shifts, which included changes in the distribution of food species, varied greatly when considering various scenarios of change in biotic factors, providing a warning that future indirect climate and land-use change are likely to have strong but highly uncertain impacts on species biogeography. Our study confirmed that advancing our understanding of ecological networks of species interactions will improve future projections of biodiversity change, especially for modelling species distributions and their functional role under climate and land-use change scenarios, which is key for effective conservation of biodiversity and ecosystem services.

Rehabilitation of injured or immature individuals has become an increasingly used conservation and management tool. However, scientific evaluation of rehabilitations is rare, raising concern about post-release welfare as well as the cost-effectiveness of spending scarce financial resources. Over the past 20 years, events of juvenile Eurasian lynx presumably orphaned have been observed in many European lynx populations. To guide the management of orphaned lynx, we documented survival, rehabilitation and fate after the release and evaluated the potential relevance of lynx orphan rehabilitation for population management and conservation implications. Data on 320 orphaned lynx was collected from 1975 to 2022 from 13 countries and nine populations. The majority of orphaned lynx (55%) were taken to rehabilitation centres or other enclosures. A total of 66 orphans were released back to nature. The portion of rehabilitated lynx who survived at least one year after release was 0.66. Release location was the best predictor for their survival. Of the 66 released lynx, ten have reproduced at least once (8 females and 2 males). Conservation implications of rehabilitation programmes include managing genetic diversity in small, isolated populations and reintroducing species to historical habitats. The lynx is a perfect model species as most reintroduced populations in Central Europe show significantly lower observed heterozygosity than most of the autochthonous populations, indicating that reintroduction bottlenecks, isolation and post-release management have long-term consequences on the genetic composition of populations. The release of translocated orphans could be a valuable contribution to Eurasian lynx conservation in Europe. It is recommended to release orphans at the distribution edge or in the frame of reintroduction projects instead of a release in the core area of a population where it is not necessary from a demographic and genetic point of view. Rehabilitation programmes can have conservation implications that extend far beyond individual welfare benefits.

The estimation of foraging parameters is fundamental for understanding predator ecology. Predation and feeding can vary with multiple factors, such as prey availability, presence of kleptoparasites and human disturbance. However, our knowledge is mostly limited to local scales, which prevents studying effects of environmental factors across larger ecological gradients. Here, we compared inter-kill intervals and handling times of Eurasian lynx (Lynx lynx) across a large latitudinal gradient, from subarctic to the Mediterranean ecosystems, using a standardised dataset of predicted adult ungulate kills from 107 GPS-collared lynx from nine distinct populations in Europe. We analysed variations in these two foraging parameters in relation to proxies reflecting prey availability, scavengers' presence and human disturbance, to improve our understanding of lynx predation at a continental scale. We found that inter-kill intervals and handling times varied between populations, social status and in different seasons within the year. We observed marked differences in inter-kill intervals between populations, which do not appear to be driven by variation in handling time. Increases in habitat productivity (expressed by NDVI, used as a proxy for prey availability) resulted in reduced inter-kill intervals (i.e. higher kill rates). We observed less variation in handling (i.e. feeding) times, although presence of dominant scavengers (wild boars and brown bears) and higher human impact led to significantly shorter handling times. This suggests that kleptoparasitism and human disturbance may limit the energetic input that lynx can obtain from their prey. We also observed that the human impact on foraging parameters can be consistent between some populations but context-dependent for others, suggesting local adaptations by lynx. Our study highlights the value of large-scale studies based on standardised datasets, which can aid the implementation of effective management measures, as patterns observed in one area might not be necessarily transferable to other regions. Our results also indicate the high degree of adaptability of these solitary felids, which enables them to meet their energy requirements and persist across a wide range of environmental conditions despite the constraints imposed by humans, dominant scavengers and variable prey availability.

Translocations are central to large carnivore restoration efforts, but inadequate monitoring often inhibits effective conservation decision-making. Extinctions, reintroductions, poaching and high inbreeding levels of the Central European populations of Eurasian lynx (Lynx lynx) typify the carnivore conservation challenges in the Anthropocene. Recently, several conservation efforts were initiated to improve the genetic and demographic status, but were met with variable success. Here, we report on a successful, stakeholder-engaged translocation effort to reinforce the highly-inbred Dinaric lynx population and create a new stepping-stone subpopulation in the Southeastern Alps. We used multidisciplinary and internationally-coordinated monitoring using systematic camera-trapping, non-invasive genetic sampling, GPS-tracking of translocated and remnant individuals, recording of reproductive events and interspecific interactions, as well as the simultaneous tracking of the public and stakeholder support of carnivore conservation before, during and after the translocation process across the three countries. Among the 22 translocated wild-caught Carpathian lynx, 68% successfully integrated into the population and local ecosystems and at least 59% reproduced. Probability of dispersing from the release areas was 3-times lower when soft-release rather than hard-release method was used. Translocated individuals had lower natural mortality, higher reproductive success and similar ungulate kill rates compared to the remnant lynx. Cooperation with local hunters and protected area managers enabled us to conduct multi-year camera-trapping and non-invasive genetic monitoring across a 12,000-km2 transboundary area. Results indicate a reversal in population decline, as the lynx abundance increased for >40% during the 4-year translocation period. Effective inbreeding decreased from 0.32 to 0.08-0.19, suggesting a 2- to 4-fold increase in fitness. Furthermore, successful establishment of a new stepping-stone subpopulation represents an important step towards restoring the Central European lynx metapopulation. Robust partnerships with local communities and hunters coupled with transparent communication helped maintain high public and stakeholder support for lynx conservation throughout the translocation process. Lessons learned about the importance of stakeholder involvement and multidisciplinary monitoring conducted across several countries provide a successful example for further efforts to restore large carnivores in human-dominated ecosystems. ### Competing Interest Statement The authors have declared no competing interest.

ABSTRACT Biotic interactions are expected to influence species’ responses to climate change, but they are usually not included when predicting future range shifts. We assessed the importance of biotic interactions to understand future consequences of climate and land use change for biodiversity using as a model system the brown bear ( Ursus arctos ) in Europe. By including biotic interactions using the spatial variation of energy contribution and habitat models of each food species, we showed that the use of biotic factors considerably improves our understanding of the distribution of brown bears. Predicted future range shifts, which included changes in the distribution of food species, varied greatly when considering various scenarios of change in biotic factors, warning about future indirect climate change effects. Our study confirmed that advancing our understanding of ecological networks of species interactions will improve future scenarios of biodiversity change, which is key for conserving biodiversity and ecosystem services.

Determination of parentage provides valuable information for the conservation of wild populations, for instance, by allowing the monitoring of breeding success and inbreeding. Between 1999 and 2002, nine brown bears ( Ursus arctos ) were translocated to augment the remnant population of a few surviving individuals in the Italian Alps, but only part of them reproduced, with a higher inbreeding risk occurrence in the long-time. Currently, in the Alpine population, parentage tests are assessed through the analysis of 15 microsatellite loci (STRs), but the reduction of genetic variability in future generations will need the use of additional informative markers. Single nucleotide polymorphisms (SNPs) have been proven to be useful and reliable in individual identification and family reconstruction; moreover, they can perform well on low-quality samples. In this study, we analysed 51 SNPs to generate a SNP multilocus genotype dataset of 54 Alpine brown bears ( Ursus arctos ) and compared its performance in parentage analysis with the validated STR dataset. We found that SNPs alone are not sufficient to determine parentage relationships, but the combination of SNPs and STRs provided unambiguous parentage assignments. The combined panel also performed better than STRs when true parents were not present in the dataset and, consequently, showed higher values of assignment probabilities.

The Authors outline the present situation of the Eurasian otter Lutra lutra in Friuli Venezia Giulia Region (north-eastern Italy). After about 50 years from its local extinction, the species is surely coming back. The return probably dated back to 2006, but the first proof was a road kill on the Friulian Morainic Hills in 2011. Biomolecular data indicated an Austrian origin of this first specimen. Field researches did not confirm this evidence until 2014, when otter spraints were found near Fusine in Valromana (Tarvisio, Udine), close to the Italian-Austrian border. Further field work confirmed that the whole Italian Danube Catchment from Tarvisio Municipality is inhabited by a breeding nucleus of 4 to 7 otters. Further bridge otter survey indicated that the distribution of the otters in the whole Friuli Venezia Giulia Region was still increasing, both on the Carnic, Julian and Karavanke Alps, up to the border with Veneto Region. The cohabitation with Neovison vison (Western Carnic Alps) and the road mortality (8 road kills from 2011 to 2019) represent possible threats to the establishment of a viable population in north-eastern Italy.

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.

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The project Status and Conservation of the Alpine Lynx Population (SCALP) is an ongoing program aiming to co-ordinate the lynx monitoring and propose conservation activities in the Alps. The SCALP project was initiated from several active lynx researchers as an informal group in the early 1990s twenty - years after the reintroductions in Switzerland, Italy, Slovenia, and Austria. To propose adequate management measures, a sound monitoring of the Alpine lynx population needs to be in place. In the early 1990s the first efforts were made to put all available data on lynx presence together. The least common denominator of data collection in the Alps was - and still is - the compilation of direct and indirect signs of lynx presence. To standardise the interpretation of the data collected, SCALP experts agreed on a categorisation of occurrence records, where each record is evaluated retrospectively whether it can be verified for correct species identification and whether it has been verified for correct species identification. Therefore, for the monitoring of the lynx throughout the Alps in the frame of the SCALP surveys, the collected data are classified in three categories according to the following SCALP criteria: Category 1 (C1): "Hard facts", verified and unchallenged observations; Category 2 (C2): Observations controlled and confirmed by a lynx expert (e.g. trained member of the network); Category 3 (C3): Unconfirmed category 2 observations and all observations such as sightings and calls which, if not additionally documented, by their nature cannot be verified. The SCALP criteria allow to both combine and distinguish reliable and only partly reliable data for a better interpretation of the actual distribution.

To assess the status of lynx we analysed lynx signs of presence within the range of the Italian Alps from 2005 to 2009. A total of 268 signs have been collected, compared to 411 signs during the previous pentad. The distribution of the confirmed signs of lynx presence isconfined to three concise areas: the North-eastern Alps of Friuli VG, the Trentino province and the Ossola valley in the Piedmont region. Occupancy modelling revealed a decrease of the lynx range by one third: The estimated number of occupied 100 km2 cells decreased from 34 (pentad: 2000–2004) to 21 (pentad: 2005–2009). Less than 10% of the Italian Alps are colonized. We estimated the number of lynx present in all the Italian Alps at less than 15 individuals. Therefore, the persistence of lynx in the Italian Alps highly depends on immigration from neighbouring countries.