Marco Dietmar Heurich

• Heurich, Marco Dietmar; Signer, Johannes; Peters, Anne; Dupke, Claudia; Lamprecht, Nick & Heurich, Marco Dietmar (2026). Recreational activities and human hunting strongly influence red deer space use to trails. Ecosphere. 17(9). doi: 10.1002/ecs2.70756. Full text in Research Archive
• Morelle, Kevin; Wielgus, Elodie; Brogi, Rudy; Bhardwaj, Manisha; Chamaillé-Jammes, Simon & Baubet, Eric [Show all 25 contributors for this article] (2026). Spatio-temporal patterns and risk factors of wild boar–pig farm contact across Europe. Journal of Applied Ecology. ISSN 0021-8901. 63(2). doi: 10.1111/1365-2664.70314. Full text in Research Archive
• Mináriková, Tereza; Belotti, Elisa; Krausová, Josefa; Gahbauer, Martin; Engleder, Thomas & Bednářová, Hana [Show all 13 contributors for this article] (2026). Protected areas and hunting system affect the survival and longevity of adult female Eurasian lynx in a source–sink population. Conservation Science and Practice (CSP). 8(7). doi: 10.1111/csp2.70325. Full text in Research Archive
• Stenbacka, Desirée Guidobaldi; Stenbacka, Fredrik; Heurich, Marco Dietmar; Ericsson, Göran & Neumann, Wiebke (2026). Unveiling the patchwork: landscape arrangement drives moose winter utilization of forests. Landscape Ecology. ISSN 0921-2973. 41(7). doi: 10.1007/s10980-026-02404-0. Full text in Research Archive Show summary

  Context Landscape heterogeneity is a key driver of ecological processes, yet how spatial structure influences animal space use across scales remains insufficiently understood. In managed boreal forests, the composition and configuration of forest patches in the landscape may constrain how large herbivores use their winter habitat. Objectives We examined how multi-scale structural metrics of young forest patches shape utilization intensity within moose (Alces alces) winter ranges and core areas. Methods Using GPS data from 176 adult moose across seven populations in Sweden (2016–2024; 62–68°N), we estimated winter ranges with Biased Random Bridge (BRB) models to quantify utilization distributions (UDs). We distinguished intensively used core zones (50% UD) from peripheral zones (95–50% UD) within a given winter range. The landscape was classified into three habitat classes biologically relevant for moose during winter: young forest (tree height < 5 m), forest (tree height ≥ 5 m), and non-forest. For each moose and winter season, UDs were linked with multi-scale landscape metrics characterizing patch area, patch cohesion, fragmentation, and edge density. Linear Discriminant Analysis was conducted to identify structural differences between core areas and peripheral zones across three spatial levels, and mixed models were used to determine whether utilization intensity varied with patch structure, connectivity, snow depth, and soil moisture. Results Patches differed structurally between core areas and peripheral zones. Core areas were characterised by fewer, larger, and more consolidated patches with higher young forest (< 5 m) representation, while peripheral zones displayed greater patch fragmentation, higher patch cohesion, and larger patches of forest with larger trees (≥ 5 m) across all habitat classes. Individual patch geometry did not differ between core areas and peripheral zones at any site. These patterns were consistent across populations. Within core areas, moose utilization intensity was positively associated with edge density and cohesion of forest (≥ 5 m), and negatively associated with young forest patch area, suggesting that moose concentrate their winter space use in well-connected, edge-rich forest interspersed with small young forest patches. Conclusions Landscape arrangement exerts a strong influence on the spatial distribution of a large herbivore such as moose within managed boreal forest matrices. Structural features of the landscape mediate behavioural responses to resource distribution and environmental constraints, shaping how animals organise and concentrate their winter habitat use. This highlights landscape structure as a behavioural filter linking forest management patterns to animal movement, with direct implications for forest planning aimed at redistributing winter space use and possibly reducing localized browsing damage.

• Kudrenko, Svitlana; Bischof, Richard; Zedrosser, Andreas; Selva, Nuria; Korepanova, Kateryna & Vyshnevskiy, Denys [Show all 12 contributors for this article] (2026). Changes in wildlife activity patterns in response to war in Ukraine. Science. ISSN 0036-8075. 392(6804), p. 1282–1286. doi: 10.1126/science.aed1493. Full text in Research Archive Show summary

  Conflict zones are inherently hazardous and inaccessible for researchers, which results in a knowledge gap about the immediate effects of armed conflicts on the environment, particularly wildlife. We used camera-trap detections to investigate the impact of armed conflict on wildlife activity patterns before, during, and after the Russian occupation of the Chornobyl Exclusion Zone (Ukraine) in 2022 and compared it to the same period in 2021. Mammal species responded to armed conflict through immediate behavioral adjustments, including reduced activity during night and on dates when armed-conflict activities intensified. Our results provide insight into wildlife’s behavioral responses to armed conflict in real time and underscore the potential of camera trapping to quantify the ecological effects of war.

• Bauer, Timo Konstantin; Palmero, Stefano; Gottschalk, Eckhard & Heurich, Marco Dietmar (2026). Ecosystem Engineers at Work: How Beaver Ponds Reshape Avian Abundance and Diversity in a Mountainous Forest Ecosystem in Central Europe. Ecology and Evolution. 16(7). doi: 10.1002/ece3.74016. Full text in Research Archive Show summary

  By building dams and creating ponds, the Eurasian beaver (Castor fiber) acts as an ecosystem engineer, generating habitats for species that depend on wetland and freshwater ecosystems, which are increasingly threatened worldwide. Birds in particular may benefit from these habitats as feeding or breeding grounds. To assess the effects of beaver ponds on avifauna communities, we conducted six 20-min bird counts between April and June 2021 at 15 beaver ponds and 15 control plots along unmodified streams in the Bavarian Forest National Park, where natural freshwater habitats are scarce. In total, 46 bird species were recorded, of which 13 occurred exclusively at beaver ponds and three only at control sites. Using multiple regression analysis, we investigated the effects of beaver ponds, pond size and a set of environmental variables including habitat openness, standing dead wood and the proportion of deciduous and coniferous trees. Bird abundance was 23% higher at beaver ponds than at control sites. In particular, species associated with aquatic habitats for feeding and breeding occurred at significantly greater abundances at beaver ponds. Species richness and abundance increased with pond surface area, and the largest ponds supported the most distinct bird communities as well as the highest richness and abundance. Moreover, bird community composition differed significantly between beaver ponds and control plots. Our findings demonstrate that beaver-created wetlands substantially alter bird community composition and enhance habitat availability for wetland-associated species. These results highlight the important role of beavers as ecosystem engineers in increasing avian diversity and promoting habitat heterogeneity in forest ecosystems.

• Oeser, Julian; Kowalczyk, Rafał; Kuijper, Dries; Neumann, Wiebke; Reiner, Rudolf & Seidl, Rupert [Show all 65 contributors for this article] (2026). Increasing forest disturbance enhances habitat suitability for Europe’s large herbivores. Nature Ecology and Evolution. 10, p. 1273–1286. doi: 10.1038/s41559-026-03096-0. Full text in Research Archive Show summary

  Forest disturbances have increased in many regions, but how they impact habitat suitability for wildlife remains poorly understood. Here, by combining tracking data on 3,069 individuals of four ungulate species (European bison, moose, red deer and roe deer) with satellite-based maps, we perform a continental, multi-decadal assessment of large herbivore responses to forest disturbance. Despite strong intraspecific variation, all species show an increased selection of disturbed areas for ≥35 years after disturbance. Although the patterns closely reflect species-specific foraging strategies, all species selected more strongly for smaller disturbance patches, depending on the availability of alternative foraging habitats (grasslands and croplands). Model projections across the species’ range extents show positive but regionally varying effects of forest disturbances on habitat suitability between 2000 and 2023. Our findings indicate that forest disturbances can attract large herbivores and that the recent increase in forest disturbances improved habitat suitability for our study species across Europe, highlighting the importance of considering long-term disturbance-related dynamics for wildlife and forest management. Given expected future increases in disturbance, resulting habitat improvements could amplify conflicts with forestry, but also contribute to restoring large herbivores and their ecological functions.

• Kudrenko, Svitlana; Bischof, Richard; Zedrosser, Andreas; Borsuk, Oleksandr; Fiderer, Christian & Smith, Adam F. [Show all 13 contributors for this article] (2026). The Chornobyl Exclusion Zone as a wildlife refuge: restricted human access shaped mammal recolonization. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2071). doi: 10.1098/rspb.2025.3151. Full text in Research Archive Show summary

  Land-use changes and habitat degradation threaten biodiversity and ecosystem functions globally. Large terrestrial mammals are particularly vulnerable due to low reproductive rates, large spatial requirements and sensitivity to human disturbances. Increasing coverage and effectiveness of protected areas (PAs) is vital to conserve mammal species and their habitats. We used camera trapping to assess the impact of human activities and landscape characteristics on diversity, occupancy and detection probabilities of 11 terrestrial mammals in northern Ukraine in 2020–2021. We evaluated the impact of human stressors and landscape modifications on species diversity, occupancy and detection probabilities across the Ukrainian Chornobyl Exclusion Zone (CEZ), regional PAs and non-PAs. We implemented hierarchical Bayesian single-species single-season occupancy models to identify the covariates that described the occupancy (Ψ) and detection (p) probabilities for each species. Species diversity, occupancy and detection probabilities were significantly higher in the Ukrainian CEZ and neighbouring Drevlianskyi Nature Reserve (highest occupancy probabilities of Przewalski’s horse, Eurasian lynx, moose and red deer) than in all other areas. PA coverage positively influenced red deer, red fox and raccoon dog occupancies, while PA protection status showed mixed effects across species. Our results demonstrate that PAs are most effective when they are large, contiguous and human access restrictions are actively enforced.

• Mosig, Clemens; Vajna-Jehle, Janusch; Mahecha, Miguel D.; Cheng, Yan; Hartmann, Henrik & Montero, David [Show all 206 contributors for this article] (2026). deadtrees.earth — An open-access and interactive database for centimeter-scale aerial imagery to uncover global tree mortality dynamics. Remote Sensing of Environment. ISSN 0034-4257. 332. doi: 10.1016/j.rse.2025.115027. Full text in Research Archive Show summary

  Excessive tree mortality is a global concern and remains poorly understood as it is a complex phenomenon. We lack global and temporally continuous coverage on tree mortality data. Ground-based observations on tree mortality, e.g., derived from national inventories, are very sparse, and may not be standardized or spatially explicit. Earth observation data, combined with supervised machine learning, offer a promising approach to map overstory tree mortality in a consistent manner over space and time. However, global-scale machine learning requires broad training data covering a wide range of environmental settings and forest types. Low altitude observation platforms (e.g., drones or airplanes) provide a cost-effective source of training data by capturing high-resolution orthophotos of overstory tree mortality events at centimeter-scale resolution. Here, we introduce deadtrees.earth, an open-access platform hosting more than two thousand centimeter-resolution orthophotos, covering more than 1,000,000 ha, of which more than 58,000 ha are manually annotated with live/dead tree classifications. This community-sourced and rigorously curated dataset can serve as a comprehensive reference dataset to uncover tree mortality patterns from local to global scales using space-based Earth observation data and machine learning models. This will provide the basis to attribute tree mortality patterns to environmental changes or project tree mortality dynamics to the future. The open nature of deadtrees.earth, together with its curation of high-quality, spatially representative, and ecologically diverse data will continuously increase our capacity to uncover and understand tree mortality dynamics.

• Liang, Yutong; Mattisson, Jenny; Andren, Henrik; Linnell, John Durrus; Nilsen, Erlend B. & Odden, John [Show all 37 contributors for this article] (2026). Age-specific patterns of reproductive success in wild female Eurasian lynx across Europe. Biology Letters. ISSN 1744-9561. 22(5). doi: 10.1098/rsbl.2025.0748. Full text in Research Archive Show summary

  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.

• Arribas, Eva Sánchez; Planillo, Aimara; Premier, Joe; Kürschner, Tobias; Belotti, Elisa & Breitenmoser-Würsten, Christine [Show all 26 contributors for this article] (2026). Translocation effects on regional and local population viability and connectivity. Conservation Biology. ISSN 0888-8892. 40(4). doi: 10.1111/cobi.70321. Full text in Research Archive Show summary

  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.

• Kou, Mengxi; Lwin, Ye Htet; Wang, Yifu; Peng, Wanting; König, Hannes & Heurich, Marco Dietmar (2026). Current patterns and mitigation strategies of human-wildlife conflicts in Chinese protected areas. Global Ecology and Conservation. 68. doi: 10.1016/j.gecco.2026.e04194. Full text in Research Archive Show summary

  Human-wildlife conflicts (HWCs), driven by habitat fragmentation, species recovery, and climate change, have intensified globally and are increasingly prevalent in China, especially in and around protected areas (PAs). This study investigates HWCs in 164 PAs across mainland China, addressing three critical gaps: (1) the relationship between HWC prevalence and biodiversity hotspots, (2) dominant conflict types, and (3) effectiveness of mitigation strategies. Using a nationwide online survey of PA rangers with direct HWC experience, we found that 54.4% of surveyed PAs reported conflicts. Central and southeastern China exhibited the highest frequency and severity. Wild boars (Sus scrofa) were the most commonly reported species (40.9%), followed by bears (Ursus arctos and Ursus thibetanus, 14.0%) and macaques (Macaca mulatta and Macaca thibetana, 13.5%). Over 63% of affected PAs faced multi-species conflicts, with crop damage being the most widespread issue. Generalized linear models revealed that the number of omnivorous species was the strongest predictor of HWC impacts across agriculture, daily life, and personal safety. Irregular PA boundaries also aggravated conflicts. Conversely, an increase in conflict-causing carnivores was associated with reduced impacts on daily life and personal safety, suggesting possible ecological suppression on omnivores. Among mitigation strategies, environmental education was rated by rangers most effective and widely used, followed by human resettlement. In contrast, measures such as economic compensation and animal removal were perceived as less effective. These findings call for a shift in HWC management priorities toward high-conflict areas beyond biodiversity hotspots. Integrated strategies tailored to omnivore-driven conflicts and strengthened education efforts are essential for fostering coexistence in China’s PAs, aligning with global conservation goals.

• Peter, Michelle; Němcová, Barbora; Twietmeyer, Sönke; Schumacher, Nico; Klamm, Alisa & Luckas, Valentin [Show all 15 contributors for this article] (2026). Deer as sentinels of emerging environmental pollution: Assessing contamination patterns and seasonal variations. Science of the Total Environment. ISSN 0048-9697. 1015. doi: 10.1016/j.scitotenv.2026.181415. Full text in Research Archive Show summary

  Environmental pollution caused by various chemicals is a pressing issue that affects every ecosystem. National parks play a special role in protecting and preserving nature. However, despite their special status as protected areas, they are not immune to environmental pollution. We assessed the pollution burden of ungulate populations in eight national parks from all over Germany. We analyzed 118 compounds from eight pollutant groups (indicators for anthropogenic pollution, active pharmaceutical ingredients (APIs), polycyclic aromatic hydrocarbons (PAHs), personal care product ingredients (PCPs), pesticides, plasticizers, persistent organic pollutants (POPs), and industrial chemicals) in a total of 442 liver samples from Cervus elaphus and Dama dama taken between October 2023 and January 2025. Results revealed the presence of 61 different analytes in the samples. Parallel detected analytes in samples ranged from 14 to 33, (median 18). APIs and pesticides went largely undetected, whilst contamination with PAHs and PCPs was comparable among all eight parks and three age groups (fawn, subadult and adult). We are the first to report on such a wide range of specific compounds in ungulates, particularly emerging groups of pollutants. Determined concentrations of anthropogenic pollutants, industrial chemicals, plasticizers and POPs differed between parks. Statistical analyses and regression model fitting provided no evidence of seasonal variation in the contamination with anthropogenic pollutants, industrial chemicals, PAHs and POPs. The high number of analytes detected in parallel is alarming in terms of potential cocktail effects and underlines the importance of sustainable management of environmental pollution and further research into emerging pollutants.

• Cerri, Jacopo; Chirichella, Roberta; Arnold, Walter; Bartoš, Luděk; Borowik, Tomasz & Carranza, Juan [Show all 33 contributors for this article] (2026). Trends of ungulate species in Europe: not all stories are equal. Mammal Research. ISSN 2199-2401. 71(2). doi: 10.1007/s13364-025-00838-6. Full text in Research Archive
• Gehr, Benedikt; Smith, Adam F.; Ciuti, Simone; Muff, Stefanie; Bonnot, Nadège C. & Ossi, Federico [Show all 20 contributors for this article] (2026). Navigating multi-predator dynamic risk landscapes in anthropogenic environments: spatio-temporal plasticity in roe deer habitat selection. Landscape Ecology. ISSN 0921-2973. 41(3). doi: 10.1007/s10980-026-02301-6. Full text in Research Archive Show summary

  Context Non-lethal and lethal human activities such as hunting or agricultural practices strongly shape the movement and behaviour of wildlife populations. The recent return of natural predators in parts of the world complexifies the risk landscape for prey in anthropogenic ecosystems. Disentangling the effects of human and natural predators on the ability of hunted species to navigate dynamic landscapes of risk will improve efforts to sustainably manage game species and predators in human-dominated landscapes. Objectives We investigated how roe deer may flexibly adjust the selection for open and forest habitats to trade-off between hunting and natural predation risk. We used a large dataset across Europe with areas with and without risk from human hunting and lynx predation, while controlling for non-lethal human disturbance using the Human Footprint Index. Methods We used integrated step selection analysis at diel and seasonal temporal scales to investigate selection of open vs. forest habitats across sites differing in the occurrence and timing of the hunting season, presence of lynx, human disturbance while controlling for resource availability. Results We found no evidence that deer shifted habitat selection in presence of hunting, while lynx predation risk was associated with greater preference for open habitat at night. When both hunting and lynx co-occurred, deer selection for open and forest was driven by the presence of lynx rather than hunters. In absence of any lethal risk, deer habitat selection was driven by avoidance of non-lethal human disturbance. Time of day and season were important determinants of deer habitat selection. Conclusions We found a consistent response to predation risk by lynx, while hunting induced a more variable response, probably due to large across-site variability. Adjusting habitat selection and activity at different temporal scales as a function of these relative risks allows ungulates to navigate in the dynamic multi-risk landscape of Europe’s anthropogenic environments. Our results set the empirical baseline which will help to disentangle habitat selection and activity shifts in future hunter-predator–prey studies, as the large predator guild in Europe further re-establishes, and human impact on natural habitats increases.

• Carpentier, Cecile Agnes Edith; Heurich, Marco Dietmar; Devineau, Olivier; Gimenez, Olivier & Linnell, John D. C. (2026). Adaptive harvesting of two trophic levels stabilises predator–prey dynamics. Simulations with Eurasian lynx and European roe deer. Wildlife Biology. ISSN 0909-6396. doi: 10.1002/wlb3.01628. Full text in Research Archive Show summary

  Europe has seen the recovery of many species of wild herbivores, which are now widespread across much of the continent. In addition, large carnivores are also recolonising many European countries. Most ungulates are managed through hunting, but natural predation can also have a significant influence in many areas. Therefore, the management of large herbivores must increasingly account for both hunting pressure and the impact of predation. Recent studies suggest that lynx predation can have a significant impact on roe deer population dynamics, both by targeting reproductive individuals and by exerting consistently high predation pressure across a wide range of prey densities. Here, we develop a two‐species predator–prey matrix population model that integrates lynx and roe deer through functional and numerical responses. We test a set of management rules, applied to both prey and predators, to examine whether joint hunting of both species can prevent prey declines and stabilise the population dynamics. Our simulations show that protecting (i.e. not hunting) either species increases the predator population, which in turn leads to a decline in the prey population. Hunting only the prey worsens their fate due to the addition of hunting and predation. However, simultaneous hunting of predators and prey, adaptively regulated through simple heuristics, does help prevent prey declines. We also show that the initial densities of the predator and prey population have significant impact on the outcome of the simulations. The importance of relative predator and prey population densities highlights the need for adaptive harvesting that monitors and adjusts to current predator and prey population levels.

• Liang, Yutong; Kramer-Schadt, Stephanie; Mattisson, Jenny; Belotti, Elisa; Bufka, Luděk & Melovski, Dime [Show all 45 contributors for this article] (2026). Extra-territorial excursions of Eurasian lynx ( Lynx lynx ) during the mating season across Europe. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2063). doi: 10.1098/rspb.2025.2235. Full text in Research Archive Show summary

  Extra-territorial mating excursions (i.e. short-term movements beyond established home ranges to seek mating opportunities) represent an underexplored reproductive strategy in felids. Using telemetry data from 125 Eurasian lynx (172 lynx-years, 1995–2023) across Europe, we investigated sex-specific spatio-temporal patterns and drivers of these excursions during the mating season. Overall, 33% of males and 11% of females undertook excursions, with males having higher rates than females. Male excursions mostly occurred in March, coinciding with the peak of the conception period, while females tended to undertake excursions either before or after this peak. The median Euclidean distance travelled beyond the home range was 6.8 km for males and 2.6 km for females, with corresponding median durations of 119 h and 85 h, respectively. Translocated individuals exhibited higher excursion rates than those in established populations, suggesting mate-searching in novel environments. We found no evidence that human influences affected excursion rates or distances. Our findings highlight a mating tactic that is often overlooked and provide new insight into sex-specific and context-dependent movement strategies in Eurasian lynx. By linking extra-territorial excursions to reproduction patterns, our study informs future research on mate-searching behaviour in felids and offers implications for conservation planning, particularly in isolated or reintroduced populations.

• Suessle, Vanessa; Heurich, Marco Dietmar; Downs, Colleen T.; Weinmann, Andreas & Hergenroether, Elke (2025). CNN-Based Flank Predictor for Quadruped Animal Species. IET Computer Vision. ISSN 1751-9632. 19(1). doi: 10.1049/cvi2.70024. Full text in Research Archive Show summary

  The bilateral asymmetry of flanks, where the sides of an animal with unique visual markings are independently patterned, complicates tasks such as individual identification. Automatically generating additional information on the visible side of the animal would improve the accuracy of individual identification. In this study, we used transfer learning on popular convolutional neural network (CNN) image classification architectures to train a flank predictor that predicted the visible flank of quadruped mammalian species in images. We automatically derived the data labels from existing datasets initially labelled for animal pose estimation. The developed models were evaluated across various scenarios involving unseen quadruped species in familiar and unfamiliar habitats. As a real-world scenario, we used a dataset of manually labelled Eurasian lynx (Lynx lynx) from camera traps in the Bavarian Forest National Park, Germany, to evaluate the model. The best model on data obtained in the field was trained on a MobileNetV2 architecture. It achieved an accuracy of 91.7% for the unseen/untrained species lynx in a complex unseen/untrained habitat with challenging light conditions. The developed flank predictor was designed to be embedded as a preprocessing step for automated analysis of camera trap datasets to enhance tasks such as individual identification.

• Braun, Kira; Döringer, Stefanie & Heurich, Marco Dietmar (2025). A discourse analysis of print media coverage on the recolonization of the wolf in Germany. Biological Conservation. ISSN 0006-3207. 310. doi: 10.1016/j.biocon.2025.111351. Full text in Research Archive Show summary

  Since the turn of the century, wolves have recolonized large areas in Central Europe. While some view this as a conservation success, others emphasize the problems caused by the renewed presence of the wolf. Media, which both reflects and shapes public attitudes, has increasingly been analyzed to understand the wolf discourse in Europe and the U.S. The present study connects to this research and examines German print coverage from 2000 to 2022, following the natural return of wolves, by applying structural topic modeling to identify prevalent topics, temporal trends, and spatial differences. The media analysis covers two national newspapers—Bild (n = 242) and Süddeutsche Zeitung (n = 125)—and two regional papers, Lausitzer Rundschau (n = 1026) and Passauer Neue Presse (n = 268). The most frequent topics included lethal control, wolf monitoring, and livestock depredation, with educational work being prominent only in regional coverage. Over time, topics on wolf monitoring and educational work decreased in regional newspapers, while management issues increased. Differences were also observed between Bild (tabloid press) and Süddeutsche Zeitung (quality press). Bild focused on livestock attacks, while this was not a key topic in Süddeutsche Zeitung. The results show that in Germany the dissemination of information on monitoring and biological status is often of high-quality from wolf experts, which tends to generate trust. Further, the findings suggest that educational events, such as film festivals, and the reporting of monitoring results, could represent crucial instruments for spreading information about the conservational value of large carnivores, particularly by reaching a wide but also regional audience.

• Vorel, Aleš; Mokrý, Jan; Oldřich, Vojtěch; Gahbauer, Martin; Toulec, Tadeáš & Horníček, Jan [Show all 19 contributors for this article] (2025). Population dynamics of grey wolves in the Bohemian Forest Ecosystem. Silva Gabreta. ISSN 1211-7420. 31, p. 83–100. Full text in Research Archive Show summary

  The ongoing wolf’s recolonization of continental Europe at the beginning of the 21st century recently reached many regions where wolves were absent for centuries, including several areas on the Czechia’s borders. We observed the process of wolf recolonization across the Bohemian Forest Ecosystem from 2015 until April 2023. We adopted a multifaceted approach, based on systematic tracking surveys, camera traps, telemetry, and provoked howling. The first breeding pair with permanent occupation was detected in 2016, connecting two major European wolf populations – Alpine and Central European. We observed increasing amounts of confirmed wolf occurrence data from 2015 to April 2023, with camera trap pictures and scats being the most abundant data sources. The implications of intensive population expansion were confirmed by locating six activity centres in the wolf year 2022/2023, reflecting six existing packs in the Bohemian Forest Ecosystem. Although those wolf packs spread practically across the whole study area in eight wolf years, the intense phase of recolonization is probably finished, and only continuous small changes in population density are expected. Further observations on the population dynamics are essential, focusing on the transitions between existing packs and the establishment of new territories within the existing social structure.

• Haas, Nikolaus; Velling, Marc; Henrich, Maik; Peters, Wibke Erika Brigitta; Peterka, Tomáš & Červenka, Jaroslav [Show all 10 contributors for this article] (2025). Effects of opening winter enclosures on red deer movement and local browsing pressure: An experimental assessment. Forest Ecology and Management. ISSN 0378-1127. 602. doi: 10.1016/j.foreco.2025.123379. Full text in Research Archive Show summary

  Winter enclosures are an important wildlife management tool in mountainous regions of Central Europe. They are implemented to reduce browsing pressure and bark peeling caused by red deer (Cervus elaphus) during winter by lowering their numbers in the surrounding landscape. However, the enclosures require high levels of maintenance and increase local animal densities, which could potentially enhance the spread of diseases and parasites. Therefore, it is of great interest to evaluate the effectiveness of winter enclosures in restricting red deer movement and minimizing browsing damage. Thus, this study employs an experimental approach to analyse the impact of winter enclosure management on these two parameters in the Bohemian Forest Ecosystem. Three treatments were implemented: (1) four winter enclosures kept closed (regular management), (2) four winter enclosures opened earlier (opened earlier), and (3) two winter enclosures left open all winter (open fences).The median winter home range of red deer increased sixfold under the open fences treatment compared to the previous year, though the home ranges still did not extend beyond the borders of the protected area. At the same time, browsing probabilities for all tree species decreased in the vicinity of the enclosures in the open fences treatment. No change in browsing probability was observed around the enclosures opened earlier compared to the previous year. These results suggest that the main factor contributing to changes in browsing pressure caused by the experimental treatments was that red deer overwintering outside the open fences enclosures gained access to supplementary feeding in winter, consequently reducing their browsing activities in the vicinity of these enclosures. Therefore, winter enclosures may not always outperform unfenced feeding stations as a management tool to reduce browsing pressure.

• Gatiso, Tsegaye T.; Kulik, Lars; Bachmann, Mona; Bonn, Aletta; Bösch, Lukas & Freytag, Andreas [Show all 11 contributors for this article] (2025). The role of scientific evidence and social context in protected area decision making. Conservation Science and Practice (CSP). 7(12). doi: 10.1111/csp2.70182. Full text in Research Archive Show summary

  Evidence-based decision making is increasingly recognized as vital for improving the effectiveness of conservation interventions. However, its practical application in protected area (PA) management remains limited. Drawing on face-to-face interviews with PA managers from 116 PAs across Africa and Europe, we investigated the use of scientific evidence in conservation decisions and the social context under which the decisions are made. Our results revealed that most PA managers believe that there is a favorable social context, highlighting supportive community attitudes and their willingness to participate in conservation. We also found that while only about one-third of PA managers use scientific publications to inform their decisions, an overwhelming majority (85%) of PA managers rely primarily on personal experience. PA managers widely perceive the conservation interventions implemented by their respective PAs as highly effective, regardless of the type of intervention or the degree of scientific support behind it. They also recognize the trust, cooperation, and participation of local communities as crucial for the success of conservation interventions. Our study underlines that the influence of scientific evidence, particularly evidence from systematic research that has been published in peer-reviewed scientific journals, on PA-level decision making remains limited. Although the practical experience of PA managers is undeniably valuable, the underutilization of scientific evidence could undermine the effectiveness of PA managers' decisions and conservation interventions implemented by PAs. Fostering strong partnerships between researchers and PA managers (through co-designed research, mutual learning, and effective communication) can help mainstream evidence-based decision making in protected areas.

• Skidmore, Andrew K.; Abdullah, Haidi; Siegenthaler, Andjin; Wang, Tiejun; Adiningrat, Devara P. & Rousseau, Mélody [Show all 13 contributors for this article] (2025). eDNA biodiversity from space: predicting soil bacteria and fungi alpha diversity in forests using DESIS satellite remote sensing. International Journal of Remote Sensing. ISSN 0143-1161. doi: 10.1080/01431161.2025.2464958. Full text in Research Archive Show summary

  Environmental DNA (eDNA) allows thousands of microbiological taxonomic units to be identified from a small amount of environmental matrix, e.g. soil, a leaf or water. However, the spatial and temporal diversity of the microbiological world over contiguous and extensive areas remains unknown, primarily due to the typically large distances between in situ field samples which are usually collected infrequently or even one-off. Here we describe a fundamentally different approach to alpha biodiversity modelling, by coupling remote sensing image spectroscopy from the DESIS satellite with eDNA profiling using Gaussian Process Regression. Alpha diversity is mapped at a fine resolution of 30 m, and expressed using metrics including functional richness, Shannon index as well as phylogenetic diversity. Up to 50% variance in bacterial alpha diversity, and 40% of fungal alpha diversity variance, are explained by our modelling. Further, we demonstrated how ecological relations are signalled by the microbiological communities, in three European temperate forests. Our findings demonstrated for the first time using the combination of eDNA and image spectroscopy, that key ecological variables relate to alpha diversity, thereby accelerating our understanding of the spatial variation in bacterial and fungal communities across large and complex forest landscapes.

• Fagan, William F.; Krishnan, Ananke G.; Fleming, Christen H.; Ferreira, Elizabeth; Chia, Stephanie & Swain, Anshuman [Show all 179 contributors for this article] (2025). Wild canids and felids differ in their reliance on reused travel routeways. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 122(40). doi: 10.1073/pnas.2401042122. Full text in Research Archive Show summary

  Diverse factors, including environmental features and cognitive processes, can drive animals’ movements and space use, with far-reaching implications. For example, repeated use of individual-level travel routeways (directionally constrained but imperfectly aligned routes), which results in spatial concentration of activity, can shape encounter-based processes including predation, mate finding, and disease transmission. However, how much variation in routeway usage exists across species remains unknown. By analyzing GPS movement tracks for 1,239 range-resident mammalian carnivores—representing 16 canid and 18 felid species from six continents—we found strong evidence of a clade-level difference in species’ reliance on repeatedly used travel routeways. Across the global dataset, tracked canids had a 15% (±7 CI) greater density of routeways within their home ranges than did felids, rising to 33% (±16 CI) greater in landscapes shared with tracked felids. Moreover, comparisons within species across landscapes revealed broadly similar home range routeway densities despite habitat differences. On average, canids also reused their travel routeways more intensively than did felids, with hunting strategies and spatial contexts also contributing to the intensity of routeway usage. Collectively, our results suggest that key aspects of carnivore routeway-usage have an evolutionary component. Striking interspecific and clade-level differences in carnivores’ reliance on reused travel routeways within home ranges identify important ways in which the movement patterns of real-world predators depart from classical assumptions of predator-prey theory. Because such departures can drive key aspects of human-wildlife interactions and other encounter-based processes, continued investigations of the relationships between movement mechanisms and space use are critical.

• Rietz, Janine; Beudert, Burkhard; Ferry, Nicolas; Böcker, Lukas; Conraths, Franz J. & Probst, Carolina [Show all 14 contributors for this article] (2025). Temperature and pH dynamics during carcass decomposition and implications for disease management. Scientific Reports. 15. doi: 10.1038/s41598-025-07716-w. Full text in Research Archive Show summary

  Infectious diseases in wildlife threaten not only those species but also domestic animals and human health, necessitating strategies to prevent pathogen spread. The natural decomposition of carcasses may lead to pathogen inactivation due to associated increases in temperature and changes in the pH of the carcass and in the surrounding soil. In this study, the internal temperatures of 64 decomposing wild boar carcasses, the pH in the topsoil beneath 74 carcasses, and the pH of muscle and rectal tissue from 12 carcasses were monitored throughout the decomposition process. Carcass temperatures increased during decomposition, frequently exceeding 30 °C during aerobic decomposition in summer (maximum 58 °C). The pH in the carcasses increased until skeletonization, ranging from pH 4 to above pH 8. Soil pH also continuously increased during the decomposition, reaching a pH above 9 and remaining stable for at least 30 days post-skeletonization. The information on natural carcass decomposition processes provided by our study can serve as a basis for future studies to assess if elevated carcass temperatures and pH changes are sufficient for pathogen inactivation. However, our results suggest that, in most cases, neither the increase in carcass temperatures nor the changes in pH exceed the thresholds required to inactivate African swine fever virus.

• Velling, Marc; Peters, Anne; Ferry, Nicolas; Bechert, Ursula; Schwarzenberger, Franz & Göritz, Frank [Show all 9 contributors for this article] (2025). One-time administration of the SpayVac ® vaccine prevents pregnancy in red deer (Cervus elaphus) in a temperate forest ecosystem. European Journal of Wildlife Research. ISSN 1612-4642. 71(5). doi: 10.1007/s10344-025-01988-3. Full text in Research Archive Show summary

  Contraception has traditionally been used on domesticated and captive animals, but it has also found increasing application in locally overabundant wildlife species. Different immunocontraceptives are available and they vary in their mechanisms, effectiveness, and potential side-effects. In this study, the porcine zona pellucida (pZP)-based vaccine SpayVac® was administered to red deer (Cervus elaphus) in the Bavarian Forest National Park and its contraceptive effectiveness was assessed for one year under field conditions. Twenty red deer were vaccinated with a single intramuscular injection, with 27 additional animals serving as controls. All 47 deer were fitted with GPS collars. Reproduction was tracked by observing calves using camera trap surveys and by measuring the concentrations of fecal progesterone metabolites to determine pregnancy. SpayVac® reduced fertility to 11% in vaccinated deer compared to a fertility rate of 86% in control animals for one year. Camera traps and/or progesterone metabolites aided in evaluating the reproductive status of 85% of the studied female red deer. Specifically, reproductive status was determined in 37 of 46 individuals using camera traps, and pregnancy in 19 of 46 females using progesterone metabolites. In all but one deer, the same results were obtained with the two methods. Our study demonstrates the 1-year efficacy of SpayVac® immunocontraception in red deer. It also describes methods for the improved determination of pregnancy status and calf presence in wildlife, using camera traps and fecal progesterone metabolites. Studies evaluating the long-term contraceptive effectiveness and the effects of fertility control on population structure and behavior are still needed.

• Hewison, Aidan J. Mark; Cagnacci, Francesca; Gaillard, Jean Micheò; Henrich, Maik; Heurich, Marco Dietmar & Kjellander, Petter [Show all 8 contributors for this article] (2025). Roe Deer Capreolus capreolus (Linnaeus, 1758). In Melletti, Mario & Focardi, Stefano (Ed.), Deer of the World. Springer Nature. ISSN 9783031177569. p. 709–729. Full text in Research Archive Show summary

  This comprehensive chapter covers various aspects of the biology and natural history of the Roe Deer (Capreolus capreolus), including names, taxonomy, subspecies and distribution, descriptive notes, habitat, movements and home range, activity patterns, feeding ecology, reproduction, growth and survival, behavior, status in the wild and in captivity. The chapter includes a distribution map, several photos of the species, and a list of key literature.

• Henrich, Maik; Fiderer, Christian; Klamm, Alisa; Schneider, Anja; Ballmann, Axel & Stein, Jürgen [Show all 15 contributors for this article] (2025). Camera traps and deep learning enable efficient large-scale density estimation of wildlife in temperate forest ecosystems. Remote Sensing in Ecology and Conservation. doi: 10.1002/rse2.70030. Full text in Research Archive Show summary

  Automated detectors such as camera traps allow the efficient collection of large amounts of data for the monitoring of animal populations, but data processing and classification are a major bottleneck. Deep learning algorithms have gained increasing attention in this context, as they have the potential to dramatically decrease the time and effort required to obtain population density estimates. However, the robustness of such an approach has not yet been evaluated across a wide range of species and study areas. This study evaluated the application of DeepFaune, an open‐source deep learning algorithm for the classification of European animal species and camera trap distance sampling (CTDS) to a year‐round dataset containing 895,019 manually classified photos from 10 protected areas across Germany. For all wild animal species and higher taxonomic groups on which DeepFaune was trained, the algorithm achieved an overall accuracy of 90%. The 95% confidence interval (CI) of the difference between the CTDS estimates based on manual and automated image classification contained zero for all species and seasons with a minimum sample size of 20 independent observations per study area, except for two. Meta‐regression revealed an average difference between the classification methods of −0.005 (95% CI: −0.205–0.196) animals/km2. Classification success correlated with the divergence of the population density estimates, but false negative and false positive detections had complex effects on the density estimates via different CTDS parameters. Therefore, metrics of classification performance alone are insufficient to assess the effect of deep learning classifiers on the population density estimation process, which should instead be followed through entirely for proper validation. In general, however, our results demonstrate that readily available deep learning algorithms can be used in largely unsupervised workflows for estimating population densities from camera trap data.

• Dalpiaz, Naima; Krofel, Miha; Mattisson, Jenny; Vogt, Kristina; Signer, Sven & Oeser, Julian [Show all 18 contributors for this article] (2025). Variability in the movement and foraging behaviour of female Eurasian lynx during the denning season across Europe. Oikos. ISSN 0030-1299. 2025(12). doi: 10.1002/oik.11502. Full text in Research Archive Show summary

  Animal movement and reproductive behaviour are crucial components of ecological and evolutionary processes. After parturition, the behaviour of reproducing females adapts to the needs of their offspring, including thermoregulation, protection and food provisioning. However, little is known about how these adaptations vary across environmental conditions at larger scales in species with large distribution ranges. Here, we explored how female Eurasian lynx Lynx lynx movement and predation patterns change during the denning season. We analysed GPS telemetry data from two different climatic regions in Europe, cold and temperate, and evaluated the effect of explanatory variables on movement metrics and kill‐to‐den distances using generalized additive mixed models. Female lynx moved significantly longer daily distances in the cold region (central and northern Scandinavia) compared to the temperate region (southern Scandinavia and continental Europe) both before and after parturition. Reproducing females in both regions considerably reduced their movement after the start of the denning season. The typical pattern of increasing daily movements and decreasing time spent at the den with time persisted across regions, and the presence of females at the den followed a similar circadian rhythm, regardless of the markedly different daylight period. Only in the cold region females increased the distances of their excursions from the den as time passed. The distances between den and kill sites spanned from 1 to 3 km over the latitudinal range. The kill‐to‐den distances did not increase with time, but in the cold region the larger prey killsites were farther from the den than in the temperate region. Overall, our results show how some behaviours of female lynx during the denning season remain constant over a large latitudinal range, while others vary. This suggests local adaptations to particular environments, and possible increased energetic demands of reproducing females in more extreme environmental conditions.

• Adiningrat, Devara P.; Skidmore, Andrew; Schlund, Michael; Wang, Tiejun; Abdullah, Haidi & Heurich, Marco Dietmar (2025). Investigating LiDAR Metrics for Old-Growth Beech- and Spruce-Dominated Forest Identification in Central Europe. Remote Sensing. 17(2). doi: 10.3390/rs17020251. Full text in Research Archive Show summary

  Old-growth forests are essential for maintaining biodiversity, as they are formed by the complexity of diverse forest structures, such as broad variations in tree height and diameter (DBH) and conditions of living and dead trees, leading to various ecological niches. However, many efforts of old-growth forest mapping from LiDAR have targeted only one specific forest structure (e.g., stand height, basal area, or stand density) by deriving information through a large number of LiDAR metrics. This study introduces a novel approach for identifying old-growth forests by optimizing a set of selected LiDAR standards and structural metrics. These metrics effectively capture the arrangement of multiple forest structures, such as canopy heterogeneity, multilayer canopy profile, and canopy openness. To determine the important LiDAR standard and structural metrics in identifying old-growth forests, multicollinearity analysis using the variance inflation factor (VIF) approach was applied to identify and remove metrics with high collinearity, followed by the random forest algorithm to rank which LiDAR standard and structural metrics are important in old-growth forest classification. The results demonstrate that the LiDAR structural metrics (i.e., advanced LiDAR metrics related to multiple canopy structures) are more important and effective in distinguishing old- and second-growth forests than LiDAR standard metrics (i.e., height- and density-based LiDAR metrics) using the European definition of a 150-year stand age threshold for old-growth forests. These structural metrics were then used as predictors for the final classification of old-growth forests, yielding an overall accuracy of 78%, with a true skill statistic (TSS) of 0.58 for the test dataset. This study demonstrates that using a few structural LiDAR metrics provides more information than a high number of standard LiDAR metrics, particularly for identifying old-growth forests in mixed temperate forests. The findings can aid forest and national park managers in developing a practical and efficient old-growth forest identification and monitoring method using LiDAR.

• Abdullah, Haidi; Neinavaz, Elnaz; Darvishzadeh, Roshanak; Huesca, Margarita; Skidmore, Andrew K. & Lindeskog, Mats [Show all 10 contributors for this article] (2025). Integrating process-based vegetation modelling with high-resolution imagery to assess bark beetle infestation and land surface temperature effects on forest net primary productivity. Remote Sensing Applications: Society and Environment (RSASE). 37. doi: 10.1016/j.rsase.2025.101499. Full text in Research Archive Show summary

  The European spruce bark beetle (Ips typographus) is an insect species that causes significant damage to Norway spruce (Picea abies) forests across Europe. Infestation by bark beetles can profoundly impact forest ecosystems, affecting their structure and composition and affecting the carbon cycle and biodiversity, including a decrease in net primary productivity (NPP), a key indicator of forest health. The primary objective of this study is to enhance our understanding of the interplay among NPP, bark beetle infestation, land surface temperature (LST), and soil moisture content as key components influencing the effects of climate change-related events (e.g., drought) during and after a drought event in the Bavarian Forest National Park in southeastern Germany. Earth observation data, specifically Landsat-8 TIR and Sentinel-2, were used to retrieve LST and leaf area index (LAI), respectively. Furthermore, for the first time, we incorporated a time series of high-resolution (20 m) LAI as a remote sensing biodiversity product into a process-based ecological model (LPJ-GUESS) to accurately generate high-resolution (20 m) NPP products. The study found a gradual decline in NPP values over time due to drought, increased LST, low precipitation, and a high rate of bark beetle infestation. We observed significantly lower LST in healthy Norway spruce stands compared to those infested by bark beetles. Likewise, low soil moisture content was associated with minimal NPP value. Our results suggest synergistic effects between bark beetle infestations and elevated LST, leading to amplified reductions in NPP value. This study highlights the critical role of integrating high-resolution remote sensing data with ecological models for advancing the understanding of forest carbon dynamics and improving predictive capabilities to inform forest management under climate change.

• Premier, Joseph; Bastianelli, Matteo Luca; Oeser, Julian; Anders, Ole; Andren, Henrik & Aronsson, Malin [Show all 43 contributors for this article] (2025). Survival of Eurasian lynx in the human-dominated landscape of Europe. Conservation Biology. ISSN 0888-8892. 39(3). doi: 10.1111/cobi.14439. Full text in Research Archive Show summary

  Survival and cause-specific mortality rates are vital for evidence-based population forecasting and conservation, particularly for large carnivores, whose populations are often vulnerable to human-caused mortalities. It is therefore important to know the relationship between anthropogenic and natural mortality causes to evaluate whether they are additive or compensatory. Further, the relation between survival and environmental covariates could reveal whether specific landscape characteristics influence demographic performance. We used telemetry data on 681 Eurasian lynx (Lynx lynx), a model apex predator with large spatial requirements, that were tracked across their European distribution. Through time-to-event analyses, we sought to determine the variables associated with differences in their survival. Illegal killing was the main cause of mortality (33.8%), and mortality rates were similar in protected and hunted populations (8.6% and 7.0% per year, respectively). Survival varied greatly across populations (70–95% per year). Across all study sites, higher hunting and anthropogenic mortality rates were partially compensated by lower rates of other mortality causes but not by natural mortality alone. Variation in survival depended on sex (female survival was 1.5 times greater than male survival) and seasonality (highest risk during hunting season and winter), and lower survival rates were correlated with higher human modification of landscapes at both coarse (home range composition) and fine (habitat use within home range) scales. Some variation in survival was driven by unobserved factors, which, given the high rates of human-caused mortalities, including illegal killing, are of foremost concern. Due to the low natural mortality rates in protected and hunted populations, we conclude that anthropogenic causes of mortality are likely close to additive, such that maintaining or increasing refuge habitat with little human disturbance is critical to lynx conservation. cause-specific mortality, compensatory mortality, Eurasian lynx, large carnivore, Lynx lynx, survival

• Ding, Wenhui; Huang, Rong; Yao, Wei; Zhang, Wuming; Heurich, Marco Dietmar & Tong, Xiaohua (2025). A simple oriented search and clustering method for extracting individual forest trees from ALS point clouds. Ecological Informatics. ISSN 1574-9541. 86. doi: 10.1016/j.ecoinf.2024.102978. Full text in Research Archive Show summary

  Accurate extraction of individual trees has theoretical and practical significance for improving forest management and productivity levels. Although airborne laser scanning (ALS) technology is frequently utilized for large-scale forest mapping and the detection of individual trees, the challenges of detecting individual trees in multi-layered and deciduous forests remain for most canopy-based methods. This study aimed to develop an efficient individual tree detection method capable of delineating trees with various heights, especially for sub-canopy trees. Inspired by the “from bottom to top” growth characteristics of tree branches, we propose an oriented search and clustering method, which clusters tree points upwards to the local tops, making it more adaptable to the roughly conical growth characteristics of a forest’s tree canopy. On the NEWFOR dataset, our approach demonstrated comparable overall performance to that of state-of-the-art methods. In the non-dominant layers of multi-layered forests, our method achieved values of 30% in the 2–5 m range, 31% in the 5–10 m range, and 55% in the 10–15 m range, demonstrating the best extraction performance. A practical case study was conducted on selected plots of ALS point clouds acquired from the Bavarian Forest National Park (BFNP), with 1704 trees identified. This work provides a more reliable and efficient method for the future forest point cloud segmentation of individual trees; the method better meets the needs of forest inventory and resource management and lays a foundation for good forest management.

• Grella, Nina; Pedersen, Karen; Blüthgen, Nico; Busse, Annika; Donoso, David A. & Falconí-López, Ana [Show all 18 contributors for this article] (2025). Vertebrate diversity and biomass along a recovery gradient in a lowland tropical forest. Biotropica. ISSN 0006-3606. 57(1). doi: 10.1111/btp.13417. Full text in Research Archive Show summary

  Deforestation of tropical forests have resulted in extensive areas of secondary forests with the potential to restore biodiversity to former old-growth forest levels. The recovery of vertebrate communities is an essential component of biodiversity and ecosystem restoration, as vertebrates provide key ecosystem functions. However, little is known about the recovery trajectories and habitat preferences of vertebrates in tropical landscapes with differing land-use legacies. We used camera traps covering 3 weeks to study the activity of ground-based mammals and birds in the understory of 57 sites along a forest recovery gradient, ranging from active agriculture, such as pastures and cacao plantations, to naturally recovering forests and old-growth forests in the Chocó rainforest in north-western Ecuador. Our results show that diversity and biomass of wild vertebrates are highest in old-growth forests and late recovery stages, while for domestic vertebrates, these indices are highest in agricultural land. Additionally, while species-habitat networks showed low habitat specificity for vertebrate species, an indicator species analysis found no species to indicate old-growth forests, Dasyprocta punctata and Tayassu pecari to indicate all forest types, and Aramides wolfi and Pecari tajacu to indicate late regeneration forests. We suggest that these patterns are caused by a high habitat connectivity and large amounts of remaining old-growth forest in our study area. Our findings indicate that secondary forests have a high potential for the recovery of vertebrate species diversity and biomass to old-growth level in lowland tropical forests with short regeneration times.

• Naha, Dipanjan; Döringer, Stefanie & Heurich, Marco Dietmar (2025). Perception Toward Wolves Are Driven by Economic Status and Religion Across Their Distribution Range. Animals. 15(9). doi: 10.3390/ani15091196. Full text in Research Archive Show summary

  Effective conservation of large mammals depends on how people perceive them. Grey wolves have a widespread distribution globally, and their recent recolonization of human-dominated landscapes offers an excellent opportunity to understand the heterogeneity in their perception across continents. Our analysis included all quantitative studies (118 articles) conducted in 35 countries through a systematic review process, published globally between 1980–2023 and indexed in Web of Science and Google Scholar. Fifty-four percent of the studies reported a negative perception toward wolves. Most studies conducted in Asia reported a negative perception, while 56% of studies conducted in Europe and 48% in North America reported a positive perception. Fifty-four percent of studies from Western Europe and forty percent of studies from Slavic Russian cultural regions reported positive perceptions. Respondents from low-income countries elicited the most negative perceptions. We identified the predominant religion and economic status of a country as dominant factors determining perception. Studies conducted in countries with Hinduism as the predominant religion reported a negative perception toward wolves. We recommend that future studies on human–wolf interactions must prioritize regions within central Europe, parts of Asia, and Russia. A global human–wolf coexistence strategy should consider the social factors driving attitude toward the species.

• Grilo, Clara; Neves, Tomé; Bates, Jennifer; Roux, Aliza le; Medrano-Vizcaíno, Pablo & Quaranta, Mattia [Show all 56 contributors for this article] (2025). Global Roadkill Data: a dataset on terrestrial vertebrate mortality caused by collision with vehicles. Scientific Data. 12. doi: 10.1038/s41597-024-04207-x. Full text in Research Archive Show summary

  Roadkill is widely recognized as one of the primary negative effects of roads on many wildlife species and also has socioeconomic impacts when they result in accidents. A comprehensive dataset of roadkill locations is essential to evaluate the factors contributing to roadkill risk and to enhance our comprehension of its impact on wildlife populations and socioeconomic dimensions. We undertook a compilation of roadkill records, encompassing both published and unpublished data gathered from road surveys or opportunistic sources. GLOBAL ROADKILL DATA includes 208,570 roadkill records of terrestrial vertebrates from 54 countries across six continents, encompassing data collected between 1971 and 2024. This dataset serves to minimise the collection of redundant data and acts as a valuable resource for local and macro scale analysis regarding rates of roadkill, road- and landscape-related features associated with risk of roadkill, vulnerability of species to road traffic, and populations at risk of local extinction. The objective of this dataset is to promote scientific progress in infrastructure ecology and terrestrial vertebrate conservation while limiting the socio-economic costs.

• Bíl, M.; Balčiauskas, L.; Bílová, M.; Cellina, S.; Favilli, F. & Gačić, D. [Show all 42 contributors for this article] (2025). Wildlife-vehicle collision liability in Europe: A review of existing approaches and their implications. Journal of Environmental Management (JEM). ISSN 0301-4797. 380. doi: 10.1016/j.jenvman.2025.124986. Full text in Research Archive Show summary

  We present an overview of wildlife-vehicle collision (WVC) liability covering 36 European countries. We reviewed approaches to WVC liability which are currently in effect across Europe and their potential consequences for WVC reporting. To obtain relevant information, we conducted a survey, including a web-based questionnaire. We retrieved answers to questions related to human fatalities from WVC, the existence of WVC databases, roadkill data systems and recommendation for drivers in the event of WVC. In 19 countries, no one is liable when a motorized vehicle collides with a wild animal. In the remaining countries, road managers or road owners may be liable as well as drivers or hunters, either consistently or under certain conditions. Liability can, in some countries, be changed after a legal assessment. Human fatalities due to WVCs have been reported in 27 countries, with approximately 90 deaths annually across European roads. The number of injured people and estimates of socio-economic losses were not possible to obtain at a European level as many countries lack reliable databases. We discuss how existing WVC liability across countries provoke some actors to transfer liability to another actor or avoid reporting these incidents altogether. WVC underreporting in certain national databases is one of the consequences of the existing WVC liability rules in the given countries. This fact reduces the potential to identify hotspots and define appropriate mitigation measures. In conclusion, we propose several procedures for modifying WVC liability that could enhance wildlife protection and road safety.

• Schauer, Bastian; Dutschke, Marvin; Heurich, Marco Dietmar; Hoermann, Christian von; Schlüter, Jens & Lackner, Tomáš [Show all 11 contributors for this article] (2025). No genetic differentiation among populations up to 300 km apart in three species of carrion beetles. Ecological Entomology. ISSN 0307-6946. 50(6), p. 953–967. doi: 10.1111/een.13459. Full text in Research Archive Show summary

  Habitat fragmentation and loss globally threatens biodiversity and ecosystem functioning. Fragmentation disrupts gene flow and isolates populations, endangering species persistence. Dispersal ability is critical for species to maintain gene flow among populations and colonising new habitats. However, most species' dispersal abilities are unknown, raising the question of whether species are dispersal or habitat limited. Carrion beetles recycle animal necromass, an important ecosystem function. In theory, species depending on ephemeral resources such as carrion have good dispersal abilities to colonise new habitat patches regularly. However, little is known about the dispersal capacity of carrion beetles. To infer such dispersal abilities, we investigated the population genetic structure of three common carrion beetles (Coleoptera: Staphylinidae: Silphinae): Nicrophorus vespilloides Herbst, Necrodes littoralis Linnaeus and Oiceoptoma thoracicum Linnaeus. We sampled individuals using liver-baited pitfall traps and laid out carcasses in 47 sites in four regions in southern Germany. The distances between sampling sites ranged from 100 m to 320 km. We used microsatellite markers to assess population genetic structure and gene flow at local and regional spatial scales. Markers were newly developed for N. littoralis and O. thoracicum. Pairwise FST, AMOVA and DAPC analyses revealed no significant population genetic structure within all three species, indicating no limitation in gene flow, even over long distances. Our data suggest excellent dispersal abilities in all three species without critical spatial limitation at the regional scale of our study. This implies that carrion management should focus more on habitat amount rather than spatial arrangements for the conservation of carrion insects.

• Rousseau, Mélody; Groot, G. Arjen de; Skidmore, Andrew K.; Siegenthaler, Andjin; Laros, Ivo & Heurich, Marco Dietmar [Show all 8 contributors for this article] (2025). Ground-lying deadwood volume promotes soil beta diversity but not alpha diversity in European temperate forests. Plant and Soil. ISSN 0032-079X. 515, p. 579–596. doi: 10.1007/s11104-025-07600-6. Full text in Research Archive Show summary

  Background and aims Deadwood plays a vital role in forest ecosystems, influencing soil biodiversity through nutrient enrichment and niche partitioning. While the effects of specific attributes of deadwood logs on soil biodiversity are well studied, it remains unclear whether and how the volume of deadwood affects soil biodiversity at the scale of forest stands. Additionally, the effects on soil biodiversity may differ between gradually accumulated deadwood and large volumes resulting from sudden stand-level disturbance events. In this study, we aim to assess such effects on alpha and beta diversity of soil microbes and microfauna. Methods Soil samples were gathered from forest plots following a gradient of deadwood volumes in European temperate forests in Germany and The Netherlands. Using extracellular DNA metabarcoding, we analysed the soil diversity of bacteria, fungi and microarthropods. For the Bavarian Forest National Park, we also compared the diversity patterns of these biotas between areas affected by bark beetle outbreaks and unaffected areas of Norway spruce forest. Results Increased deadwood stock had a marginal effect on soil microbial and microarthropod community composition, with no impact on overall diversity. Bark beetle-affected areas had distinct soil communities, with a lower fungal and microarthropod diversity. Conclusion Our study provides the first insights into soil diversity patterns associated with increased deadwood volume at the forest stand. While shifts in soil biodiversity composition were minimal, the retention of deadwood in European temperate forests can promote heterogeneity in soil communities. Furthermore, changes in soil biodiversity following bark beetle outbreaks may have long-term consequences on forest regeneration.

• Smith, Adam F.; Kasper, Katharina; Lazzeri, Lorenzo; Schulte, Michael; Kudrenko, Svitlana & Say-Sallaz, Elise [Show all 21 contributors for this article] (2024). Reduced human disturbance increases diurnal activity in wolves, but not Eurasian lynx. Global Ecology and Conservation. 53. doi: 10.1016/j.gecco.2024.e02985. Full text in Research Archive Show summary

  Wildlife in the Anthropocene is increasingly spatially and temporally constrained by lethal and non-lethal human disturbance. For large carnivores with extensive space requirements, like wolves and Eurasian lynx, avoiding human disturbance in European landscapes is challenging when sufficient space with low disturbance is rarely available. Consequently, investigating behavioural adjustments to human presence is critical to understanding the capacity to adapt to human disturbance. We hypothesised that under low human disturbance conditions, large carnivores would adjust their temporal behaviours to make use of daytime, and when daytime human disturbance is high, they would opt for nocturnality. Using camera trap data from nine European study sites along a gradient in human disturbance, we analysed wolf and Eurasian lynx activity patterns. Our data spanned multiple years, 2014 – 2022, and we focused our analysis on September until April, when most large carnivore monitoring takes place. For wolves, our analysis revealed i) increased nocturnal behaviour, ii) decreased diurnal overlap with increasing human activity, and iii) a significant association between a higher probability of nocturnal activity and increasing human disturbance. For Eurasian lynx, we found iv) consistently nocturnal behaviours across all study sites, regardless of human disturbance, and v) no association between human disturbance and increased probability of being active during the night. Our results show that wolves can adjust to diurnal or cathemeral behaviours under low human disturbance, but shift to nocturnality when human disturbance increases. Eurasian lynx, however, consistently maintain their nocturnal behaviour, which we attribute to their principal hunting strategy of stalk and ambush. If human disturbance constrains large carnivore activity to nighttime, it could influence their interactions with prey, leading to cascading effects in the ecosystem. On the other hand, maintaining nocturnal behaviours in human-dominated landscapes may benefit large carnivore conservation, by decreasing negative interactions with humans thereby contributing to a landscape of coexistence.

• Víquez-R, Luis; Henrich, Maik; Riegel, Vanessa; Bader, Marvin; Wilhelm, Kerstin & Heurich, Marco Dietmar [Show all 7 contributors for this article] (2024). A taste of wilderness: supplementary feeding of red deer (Cervus elaphus) increases individual bacterial microbiota diversity but lowers abundance of important gut symbionts. Animal Microbiome. 6. doi: 10.1186/s42523-024-00315-6. Full text in Research Archive Show summary

  The gut microbiome plays a crucial role in the health and well-being of animals. It is especially critical for ruminants that depend on this bacterial community for digesting their food. In this study, we investigated the effects of management conditions and supplemental feeding on the gut bacterial microbiota of red deer (Cervus elaphus) in the Bavarian Forest National Park, Germany. Fecal samples were collected from free-ranging deer, deer within winter enclosures, and deer in permanent enclosures. The samples were analyzed by high-throughput sequencing of the 16 S rRNA gene. The results showed that the gut bacterial microbiota differed in diversity, abundance, and heterogeneity within and between the various management groups. Free-ranging deer exhibited lower alpha diversity compared with deer in enclosures, probably because of the food supplementation available to the animals within the enclosures. Free-living individuals also showed the highest beta diversity, indicating greater variability in foraging grounds and plant species selection. Moreover, free-ranging deer had the lowest abundance of potentially pathogenic bacterial taxa, suggesting a healthier gut microbiome. Winter-gated deer, which spent some time in enclosures, exhibited intermediate characteristics between free-ranging and all-year-gated deer. These findings suggest that the winter enclosure management strategy, including supplementary feeding with processed plants and crops, has a significant impact on the gut microbiome composition of red deer. Overall, this study provides important insights into the effects of management conditions, particularly winter enclosure practices, on the gut microbiome of red deer. Understanding these effects is crucial for assessing the potential health implications of management strategies and highlights the value of microbiota investigations as health marker.

• Ivana, Vašíčková; Pavel, Šamonil; Jakub, Kašpar; Heurich, Marco Dietmar & Leonhard, Steinacker (2024). A 400-year record of disturbance history in the Bohemian Forest Ecosystem: Lessons from unique transboundary tree-rings chronicles. Silva Gabreta. ISSN 1211-7420. 30, p. 161–177. Full text in Research Archive Show summary

  Considering the increasing frequency of disturbance events under accelerating global change, detailed knowledge about past forest dynamics forms a crucial foundation for conservation management of national parks. As sufficiently unexplored so far, our research shed light on disturbance history of the Bohemian Forest Ecosystem, comprising the Šumava Mountains and the Bavarian Forest. With a robust dendrochronological dataset of more than 6 000 trees, this is the first cross-border study dating back into the early modern era. Our aim was to compare the age structure and disturbance history on the Czech and Bavarian sides of the border using unified approach. The forest stands originated in the 17th and 18th century, with the most intense regeneration waves during the second half of the 19th century. Trees sampled on the Czech side reached significantly higher age than the Bavarian side. Despite disturbance synchronicity in the second half of the 19th century, summary disturbance histories revealed temporal variability between the Bavarian and Czech side of the border for most centuries, indicating that local storms with biotic outbreaks shaped the forest structure. Explaining the large spatial disturbance variability is challenging, suggesting different past forest management or geographic and climatic conditions as the most likely factors.

• Wierer, Amelie; Hoermann, Christian von; Benbow, M. Eric; Büchner, Christiane; Feldhaar, Heike & Fiderer, Christian [Show all 14 contributors for this article] (2024). Mechanisms determining the multi-diversity of carrion visiting species along a gradient of carrion body mass. Oecologia. ISSN 0029-8549. 206, p. 115–126. doi: 10.1007/s00442-024-05611-1. Full text in Research Archive Show summary

  Resource availability and habitat heterogeneity are essential drivers of biodiversity, but their individual roles often remain unclear since both factors are often correlated. Here, we tested the more-individuals hypothesis (MIH) and the habitat-heterogeneity hypothesis (HHH) for bacteria, fungi, dipterans, coleopterans, birds, and mammals on 100 experimentally exposed carcasses ranging by three orders of magnitude in body mass. At the level of each carcass we found marginal or significant support for the MIH for bacteria, fungi, and beetles in spring and significant support for fungi, dipterans, and mammals in summer. The HHH was supported only for bacteria in spring, while it was supported for all groups except mammals in summer. Overall multidiversity always increased with body mass, with a steeper increase in summer. Abundance based rarefaction-extrapolation curves for three classes of body mass showed the highest species richness for medium-sized carcasses, particular for dipterans and microbes, supporting the HHH also among carcasses. These findings complement existing necromass studies of deadwood, showing there are more niches associated with larger resource amounts and an increasing habitat heterogeneity between carcasses most pronounced for medium-sized species. Higher resource amount led to increased diversity of carrion-consuming organisms in summer, particularly due to the increasing number of niches with increasing size. Our findings underline the importance of distributed large carrion as well as medium-sized carrion in ecosystems supporting overall biodiversity of carrion-consumers. Furthermore, the different responses in spring and summer may inform strategies of carrion enrichment management schemes throughout the year.

• Moosavi, Sayed Jalal; Budde, Katharina Birgit; Heurich, Marco Dietmar; Mueller, Markus & Gailing, Oliver (2024). Genetic variation of English yew (Taxus baccata L.) in the Bavarian Forest National Park, Germany. European Journal of Forest Research. ISSN 1612-4669. 143, p. 1249–1265. doi: 10.1007/s10342-024-01687-9. Full text in Research Archive Show summary

  Taxus baccata L. is a highly valuable species with wide distribution but scattered and locally rare occurrence. Human intervention, including forest management practices and fragmentation, can significantly impact the species’ genetic diversity, structure, and dynamics. In this study, we investigated these factors within T. baccata populations in the Bavarian Forest National Park (NP) in Germany and their implications for conservation. We used 13 EST-SSRs to assess the genetic diversity and structure of the population. Our analysis revealed a scarcity of small-diameter trees, indicating limited natural regeneration over time. However, conservation efforts, like selectively removing competitor species and using protective fencing, have improved growth conditions and promoted seedling emergence. The NP’s natural zone has no active management, which is confined to the development and management zones. Genetic diversity assessments revealed high genetic diversity (He: 0.612 and 0.614 for seedlings and adults, respectively) compared to other studies in Taxus baccata, dispelling concerns of significant inbreeding and showcasing a stable genetic structure. However, significant spatial clustering of related individuals (family structures) in both cohorts and low effective population size in the progeny hints at restricted gene flow, necessitating conservation efforts prioritizing safeguarding and promoting natural regeneration in development and management zones. Limited natural regeneration and the recent decrease in effective population size in the NP populations indicate habitat fragmentation and human interventions. Effective population size estimates emphasize the need for diverse conservation strategies. Conservation efforts should prioritize protecting natural regeneration and enhancing gene flow by actively promoting European yew, e.g., by shelterwood cutting, to ensure the long-term viability of T. baccata in the region outside the NP.

• Bastianelli, Matteo Luca; Hoermann, Christian von; Kirchner, Katrin; Signer, Johannes; Dupke, Claudia & Henrich, Maik [Show all 16 contributors for this article] (2024). Risk response towards roads is consistent across multiple species in a temperate forest ecosystem. Oikos. ISSN 0030-1299. 2024(7). doi: 10.1111/oik.10433. Full text in Research Archive Show summary

  Roads can have diverse impacts on wildlife species, and while some species may adapt effectively, others may not. Studying multiple species' responses to the same infrastructure in a given area can help understand this variation and reveal the effects of disturbance on the ecology of wildlife communities. This study investigates the behavioural responses of four species with distinctive ecological and behavioural traits to roads in the protected Bohemian Forest Ecosystem in central Europe: European roe deer Capreolus capreolus, a solitary herbivore; red deer Cervus elaphus a gregarious herbivore; wild boar Sus scrofa, a gregarious omnivore and Eurasian lynx Lynx lynx, a solitary large carnivore. We used GPS data gathered from each species to study movement behaviour and habitat selection in relation to roads using an integrated step selection analysis. For all species and sexes, we predicted increased movement rates in response to roads, selection of vegetation cover near roads and open areas after road crossings, and increased road avoidance during the day. We found remarkably similar behavioural responses towards roads across species. The behavioural adaptations to road exposure, such as increased movement rates and selection for vegetation cover, were analogous to responses to natural predation risk. Roads were more strongly avoided during daytime, when traffic volume was high. Road crossings were more frequent at twilight and at night within open areas offering food resources. Gregarious animals exposed to roads favoured stronger road avoidance over faster movements. Ungulates crossed roads more at twilight, coinciding with commuter traffic during winter. Despite differences in the ecology and behaviour of the four species, our results showed similar adaptations towards a common threat. The continuous expansion of the global transportation network should be accompanied by efforts to understand and minimise the impact of roads on wildlife to assist wildlife management and ensure conservation.

• Adiningrat, Devara P.; Schlund, Michael; Skidmore, Andrew K.; Abdullah, Haidi; Wang, Tiejun & Heurich, Marco Dietmar (2024). Mapping temperate old-growth forests in Central Europe using ALS and Sentinel-2A multispectral data. Environmental Monitoring and Assessment. ISSN 0167-6369. 196. doi: 10.1007/s10661-024-12993-5. Full text in Research Archive Show summary

  Old-growth forests are essential to preserve biodiversity and play an important role in sequestering carbon and mitigating climate change. However, their existence across Europe is vulnerable due to the scarcity of their distribution, logging, and environmental threats. Therefore, providing the current status of old-growth forests across Europe is essential to aiding informed conservation efforts and sustainable forest management. Remote sensing techniques have proven effective for mapping and monitoring forests over large areas. However, relying solely on remote sensing spectral or structural information cannot capture comprehensive horizontal and vertical structure complexity profiles associated with old-growth forest characteristics. To overcome this issue, we combined spectral information from Sentinel-2A multispectral imagery with 3D structural information from high-density point clouds of airborne laser scanning (ALS) imagery to map old-growth forests over an extended area. Four features from the ALS data and fifteen from Sentinel-2A comprising raw band (spectral reflectance), vegetation indices (VIs), and texture were selected to create three datasets used in the classification process using the random forest algorithm. The results demonstrated that combining ALS and Sentinel-2A features improved the classification performance and yielded the highest accuracy for old-growth class, with an F1-score of 92% and producer’s and user’s accuracies of 93% and 90%, respectively. The findings suggest that features from ALS and Sentinel-2A data sensitive to forest structure are essential for identifying old-growth forests. Integrating open-access satellite imageries, such as Sentinel-2A and ALS data, can benefit forest managers, stakeholders, and conservationists in monitoring old-growth forest preservation across a broader spatial extent.

• Burton, A. Cole; Beirne, Christopher; Gaynor, Kaitlyn M.; Sun, Catherine; Granados, Alys & Allen, Maximilian L. [Show all 221 contributors for this article] (2024). Mammal responses to global changes in human activity vary by trophic group and landscape. Nature Ecology and Evolution. 8, p. 924–935. doi: 10.1038/s41559-024-02363-2. Full text in Research Archive Show summary

  Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human–wildlife interactions along gradients of human influence.

• Stiegler, Jonas; Gallagher, Cara A.; Hering, Robert; Müller, Thomas; Tucker, Marlee A. & Apollonio, Marco [Show all 52 contributors for this article] (2024). Mammals show faster recovery from capture and tagging in human-disturbed landscapes. Nature Communications. 15(1). doi: 10.1038/s41467-024-52381-8. Full text in Research Archive Show summary

  Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4–7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals.

• Bernard, Marianne; Barrere, Julien; Morin, Xavier; Saïd, Sonia; Boulanger, Vincent & Granda, Elena [Show all 12 contributors for this article] (2024). Elevation affects both the occurrence of ungulate browsing and its effect on tree seedling growth for four major tree species in European mountain forests. Annals of Forest Science. ISSN 1286-4560. 81. doi: 10.1186/s13595-024-01226-x. Full text in Research Archive Show summary

  Key message In European mountain forests, the growth of silver fir (Abies alba Mill.), sycamore maple (Acer pseudoplatanus L.), European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) H. Karst.) seedlings is more strongly affected by ungulate browsing than by elevation. But, the constraint exerted by ungulates, in particular the probability for seedlings to be browsed, increases with elevation for most species. Context While concerns about mountain forest regeneration rise due to their high vulnerability to climate change, the increase in wild ungulate populations and the expansion of their range in the last decades exert an additional constraint on the survival and growth of young trees. Understanding how this constraint can vary with elevation is thus a key to assess the consequences of this population increase for the regeneration of mountain forests. Aims In this study, we investigate the effect of elevation on (i) the occurrence of browsing for seedlings and on (ii) the reduction in seedling growth induced by ungulate browsing. Methods We monitored height growth and browsing occurrence on silver fir, sycamore maple, European beech and Norway spruce seedlings across seven elevation gradients (from 400 to 2013 m) located from France to northern Sweden. Results Seedlings of the two most palatable species—fir and maple—were more likely to be browsed at high elevation while the opposite effect was observed for spruce. Browsing strongly reduced seedling growth for all species but Norway spruce, while elevation had no direct effect on seedling growth. This browsing-induced growth reduction was stronger at high elevation for fir seedlings. Conclusions Browsing is overall a stronger constraint on seedling growth than elevation for four dominant species of European mountain forests. Elevation can, however, affect both browsing probability and the effect of browsing on seedling growth. Our results highlight the importance of taking into account ungulate pressure and its interactive effect with elevation when forecasting the regeneration of mountain forests under a changing climate.

• Muther, Sandrina; Premier, Joe; Gahbauer, Martin; Hoermann, Christian von; Müller, Jörg & Heurich, Marco Dietmar (2024). Red fox cannibalism in a temperate forest ecosystem. Basic and Applied Ecology. ISSN 1439-1791. 77, p. 8–15. doi: 10.1016/j.baae.2024.03.002. Full text in Research Archive Show summary

  Scavengers benefit from carrion and simultaneously provide essential ecosystem services. To assess benefits and risks that carrion might bring, it is crucial to understand ecosystem-specific scavenger communities. Carrion research has mostly focussed on ungulate carcasses and has rarely explored the effects of carnivore carcasses, which can be critical to understanding disease transmission pathways. Therefore, using red fox, roe deer and red deer carcasses, we investigated factors that affect facultative vertebrate scavenger assemblages visiting carnivore and herbivore carcasses in a temperate forest ecosystem. Due to potentially increased disease transmission risk associated with carnivore carrion, we predicted that carnivore carcasses would be visited less and have a reduced visiting species composition compared to herbivore carcasses. Further, we expected red foxes to exhibit less consumption behavior of conspecific carcasses. We placed 22 red fox and 22 herbivore carcasses in a temperate montane protected area in Central Europe, the Bavarian Forest National Park, and analyzed the visits of all species and the consumption behavior of red fox at carcasses to understand whether these depended on carcass type. We found no significant effects of carcass type on visitation rates, visiting species composition, or red fox behavior. Cannibalism of foxes was common and, when controlling for confounding factors, e.g., elevation, temperature, and scavenging seasonality, the predicted consumption rate of red fox at conspecifics was higher than at herbivore carrion. Foxes appeared to consume conspecifics earlier than herbivore carrion, but the difference was not significant. At the very least, our results show that carnivore carcasses and fox behavior, including cannibalism, could provide a pathway for disease transmission. We thereby provide a first impression of the patterns of vertebrate scavenger assemblages at different carcass types in a temperate ecosystem and show that red fox behavior might precipitate a disease transmission pathway.

• Molinari-Jobin, Anja; Zimmermann, Fridolin; Borel, Stéphanie; Grand, Luc Le; Iannino, Elena & Anders, Ole [Show all 40 contributors for this article] (2024). Rehabilitation and release of orphaned Eurasian lynx (Lynx lynx) in Europe: Implications for management and conservation. PLOS ONE. 19(3). doi: 10.1371/journal.pone.0297789. Full text in Research Archive Show summary

  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.

• Wong, Tsz-Chung; Sani-Mohammed, Abubakar; Wang, Jinhong; Wang, Puzuo; Yao, Wei & Heurich, Marco Dietmar (2024). Classification of single tree decay stages from combined airborne LiDAR data and CIR imagery. Geo-spatial Information Science. ISSN 1009-5020. 27(6), p. 2076–2091. doi: 10.1080/10095020.2024.2311861. Full text in Research Archive Show summary

  Understanding forest health is of great importance for the conservation of the integrity of forest ecosystems. The monitoring of forest health is, therefore, indispensable for the long-term conservation of forests and their sustainable management. In this regard, evaluating the amount and quality of dead wood is of utmost interest as they are favorable indicators of biodiversity. Apparently, remote sensing-based Machine Learning (ML) techniques have proven to be more efficient and sustainable with unprecedented accuracy in forest inventory. However, the application of these techniques is still in its infancy with respect to dead wood mapping. This study, for the first time, automatically categorizing individual coniferous trees (Norway spruce) into five decay stages (live, declining, dead, loose bark, and clean) from combined Airborne Laser Scanning (ALS) point clouds and color infrared (CIR) images using three different ML methods − 3D point cloud-based deep learning (KPConv), Convolutional Neural Network (CNN), and Random Forest (RF). First, CIR colorized point clouds are created by fusing the ALS point clouds and color infrared images. Then, individual tree segmentation is conducted, after which the results are further projected onto four orthogonal planes. Finally, the classification is conducted on the two datasets (3D multispectral point clouds and 2D projected images) based on the three ML algorithms. All models achieved promising results, reaching overall accuracy (OA) of up to 88.8%, 88.4% and 85.9% for KPConv, CNN and RF, respectively. The experimental results reveal that color information, 3D coordinates, and intensity of point clouds have significant impact on the promising classification performance. The performance of our models, therefore, shows the significance of machine/deep learning for individual tree decay stages classification and landscape-wide assessment of the dead wood amount and quality by using modern airborne remote sensing techniques. The proposed method can contribute as an important and reliable tool for monitoring biodiversity in forest ecosystems.

• Hulva, Pavel; Collet, Sebastian; Baránková, Lucie; Valentová, Kamila; Šrutová, Jana & Bauer, Harald [Show all 15 contributors for this article] (2024). Genetic admixture between Central European and Alpine wolf populations. Wildlife Biology. ISSN 0909-6396. 2024(6). doi: 10.1002/wlb3.01281. Full text in Research Archive Show summary

  The recovery and expansion of formerly isolated wolf populations in Europe raise questions about the nature of their interactions and future consequences for population viability and conservation. Will fragmented populations fuse or maintain a certain level of isolation with migration? Central Europe is suitable for obtaining empirical data in this field as it represents a ‘crossroad' with the potential for contact among several phylogeographic lineages. In this study, non-invasive genetic samples obtained during population monitoring in the Bohemian and Bavarian Forest (BBF) mountain ranges in the Czech Republic and Germany (Bohemian Massif) were analysed at different neutral markers including mitochondrial sequence, nuclear autosomal microsatellites and gonosomal sex markers. Resultant genetic profiles were compared with reference data to study population ancestry. Both cluster analyses of microsatellite genotypes and syntopic occurrence of haplotypes HW01 and HW22 showed genetic admixture between Central European and Alpine populations. This represents secondary contact and interbreeding of formerly allopatric populations with different phylogeographic histories and distant expansion centres in different biomes in the Baltic region versus the Apennine peninsula and Alps. Moreover, the study describes the founding event and genealogy of this admixed deme, inhabiting intermediate environmental conditions compared to parental forms, and emphasises the role of protected areas as stepping stones in the range recolonization process in endangered large mammals.

• Schultze-Naumburg, Jonas; Port, Markus; Kramer-Schadt, Stephanie A. & Heurich, Marco Dietmar (2024). Erhaltungszustand des Luchses in Deutschland Untersuchung von Handlungsoptionen zur Verbesserung der Konnektivität. Naturschutz und Landschaftsplanung. ISSN 0940-6808. 56(10), p. 16–25. doi: 10.1399/NuL.71170. Full text in Research Archive Show summary

  Nach ihrem Aussterben kommen Luchse in Deutschland heute aufgrund von Wiederansiedlungsmaßnahmen in drei Populationen vor. Diese sind jedoch sehr klein und von anderen Vorkommen isoliert. Gelingt es nicht, sie miteinander zu vernetzen, ist mit einem Rückgang der genetischen Variabilität und mit Inzuchteffekten zu rechnen, die ein langfristiges Überleben der Art in Deutschland infrage stellen. Um die Auswirkung möglicher Managementmaßnahmen auf die Vernetzung der Luchspopulationen in Harz und Bayerischem Wald zu beurteilen, wurde ein räumlich explizites, individuenbasiertes Modell eingesetzt, das Prognosen für zukünftige Entwicklungen erlaubt. Anschließend wurden verschiedene Szenarien möglicher Wiederansiedlungen simuliert, die sich in der Anzahl ausgesetzter Tiere, dem Geschlechterverhältnis und den Aussetzungsorten unterschieden. Die Simulationen zeigen, dass sich die beiden Luchspopulationen ohne unterstützende Maßnahmen nur langsam ausbreiten, sodass erst nach etwa 50 Jahren mit einer Berührung der beiden Populationen zu rechnen ist. Sie zeigen auch, dass sich diese Entwicklung mit gezielten Wiederansiedlungen deutlich beschleunigen lässt. Am besten geeignet ist dafür der zentrale Thüringer Wald. Nach Vorhersage des Modells kann mithilfe der Wiederansiedlung eine Vernetzung bereits nach 25 Jahren erreicht werden. Nach 50 Jahren könnten wieder etwa 900 Luchse in der Modellregion leben. Insgesamt würde die Population so eine Größe erreichen, die auch langfristig ihre Überlebensfähigkeit sichert. Die vorgestellten Simulationen zeigen Handlungsmöglichkeiten auf, wie sich der Erhaltungszustand der Luchspopulationen in Deutschland verbessert lässt und die Ziele der Nationalen Strategie zur biologischen Vielfalt erreicht werden können.

• Lange, Maximilian; Preidl, Sebastian; Reichmuth, Anne; Heurich, Marco Dietmar & Doktor, Daniel (2024). A continuous tree species-specific reflectance anomaly index reveals declining forest condition between 2016 and 2022 in Germany. Remote Sensing of Environment. ISSN 0034-4257. 312. doi: 10.1016/j.rse.2024.114323. Full text in Research Archive Show summary

  Large areas of Europe have been repeatedly affected by severe droughts. Stressed trees suffered from direct drought impacts such as water stress or heat and were also more susceptible to other biotic and abiotic stress agents and calamities. Monitoring such vulnerable forests area-wide is crucial to assess the highly dynamic climate change induced impacts not captured by traditional ground-based monitoring approaches. However, most remote sensing studies dealing with forest condition are either not species-specific, not accounting for morphological and climatic conditions across different regions, not considering natural variations in phenology or not including multiple disturbance agents. Here, we extract species-specific reflectance time series separately for seven natural regions covering Germany for 2016 to 2022. The seasonal evolution of these time series serves as reference for the detection of forest condition anomalies. We calculated a similarity metric – further called forest condition anomaly index (FCA ) – between each single reflectance observation and the respective measurements within the reference time series, also considering the natural temporal deviations caused by phenology. Temporal aggregation of the FCA allows the generation of spatially comprehensive forest condition anomaly maps. We demonstrate that the FCA shows patterns related to fires, storms and insect infestations and found an overall agreement with state-of-the-art forest disturbance products using a threshold of FCA= -0.15 for forest loss. Consequently, the FCA can be used to detect forest disturbances or linked with vegetation models to assess e.g. forest biomass or carbon flux.

• Wielgus, Elodie; Henrich, Maik; Fiderer, Christian; Töws, Ariana; Michel, Jan-Niklas & Kronthaler, Franz [Show all 7 contributors for this article] (2024). Frequent flight responses, but low escape distance of wild boar to nonlethal human disturbance. Ecological Solutions and Evidence. 5(2). doi: 10.1002/2688-8319.12331. Full text in Research Archive Show summary

  Human activities can affect the behaviour and fitness of wildlife. However, the response of animals to nonlethal human activities has not been well-studied in wild boar, Sus scrofa, even though it is a widespread species in Europe and has become of increasing concern because of crop damages and its vector capacity for diseases. We study the behavioural responses of GPS-collared wild boar to nonlethal experimental human approaches in the Bohemian Forest Ecosystem along the border between Germany and the Czech Republic. We describe and quantify the flight responses of the animals and assess whether they vary with the distance to recreational paths and the occurrence of hunting in the area. We show that wild boar were disturbed and displaced by human approaches on foot in 69% of the trials, but the average flight initiation and escape distances were relatively small (93 and 256 m, respectively). The probability of a flight response decreased with distance from the paths and increased with the ruggedness of the terrain. In the non-hunting zone, the flight initiation distances and flight durations were shorter than in the hunting zone. Our results suggest a weak effect of nonlethal human disturbances on the movement of wild boar, although the animals were sensitive to the perceived risk in relation to recreation infrastructure and hunting. For the management of diseases such as African swine fever, it can be concluded that nonlethal disturbances are unlikely to accelerate the spread of the disease due to far-distance movements. Guidelines for restrictions in case of an outbreak might be adjusted accordingly.

• Kraklow, Vachel A.; Dreslerová, Dagmar; Diaconu, Andrei-Cosmin; Moravcová, Alice; Kadlec, Martin & Nývlt, Daniel [Show all 12 contributors for this article] (2024). Detecting ecological signatures of long-term human activity across an elevational gradient in the Šumava Mountains, Central Europe. Quaternary Science Reviews. ISSN 0277-3791. 344. doi: 10.1016/j.quascirev.2024.108944. Full text in Research Archive Show summary

  Central European mountains, including the Šumava Mountains located along the Czechia/Germany border, have a long and rich anthropogenic history. Yet, documenting prehistoric human impact in Central European mountain environments remains a challenge because of the need to disentangle climate and human-caused responses in terrestrial systems. Here, we present the first reconstructed water table depths (WTDs) from two sites, Pěkná and Blatenská slať, located in the Šumava Mountains. We compare these local WTD records with new and published pollen, non-pollen palynomorphs (NPPs), plant macrofossils, geochemistry and archeological records to investigate how changes in local hydrology and human activities impacted forest succession and fire activity throughout the Holocene across an elevational gradient. Using a generalized additive model, our results suggest that changes in forest succession and fire activity have been primarily caused by climate throughout the Holocene. However, humans have been utilizing mountain environments and their resources continuously since ∼4600 cal yr BP, thus playing a secondary role in modifying forest succession to increase resources beneficial to both humans and grazers. Over the last 1000 years, we provide evidence of directly observed human-caused modifications to the landscape. These results contribute to a growing body of literature illustrating human activities and landscape modifications in Central European mountains.

• Büchner, Gwen; Hothorn, Torsten; Feldhaar, Heike; Hoermann, Christian von; Lackner, Tomáš & Rietz, Janine [Show all 11 contributors for this article] (2024). Ecological drivers of carrion beetle (Staphylinidae: Silphinae) diversity on small to large mammals. Ecology and Evolution. 14(9). doi: 10.1002/ece3.70203. Full text in Research Archive Show summary

  Silphinae (Staphylinidae; carrion beetles) are important contributors to the efficient decomposition and recycling of carrion necromass. Their community composition is important for the provision of this ecosystem function and can be affected by abiotic and biotic factors. However, investigations are lacking on the effects of carrion characteristics on Silphinae diversity. Carrion body mass may affect Silphinae diversity following the more individuals hypothesis (MIH). The MIH predicts a higher number of species at larger carrion because higher numbers of individuals can be supported on the resource patch. Additionally, biotic factors like carrion species identity or decomposition stage, and the abiotic factors elevation, season and temperature could affect Silphinae diversity. To test the hypotheses, we collected Silphinae throughout the decomposition of 100 carcasses representing 10 mammal species ranging from 0.04 to 124 kg. Experimental carcasses were exposed in a mountain forest landscape in Germany during spring and summer of 2021. We analysed Silphinae diversity using recently developed transformation models that considered the difficult data distribution we obtained. We found no consistent effect of carrion body mass on Silphinae species richness and, therefore, rejected the MIH. Carrion decomposition stage, in contrast, strongly influenced Silphinae diversity. Abundance and species richness increased with the decomposition process. Silphinae abundance increased with temperature and decreased with elevation. Furthermore, Silphinae abundance was lower in summer compared to spring, likely due to increased co-occurrence and competition with dipteran larvae in summer. Neither carrion species identity nor any abiotic factor affected Silphinae species richness following a pattern consistent throughout the seasons. Our approach combining a broad study design with an improved method for data analysis, transformation models, revealed new insights into mechanisms driving carrion beetle diversity during carrion decomposition. Overall, our study illustrates the complexity and multifactorial nature of biotic and abiotic factors affecting diversity.

• Čonč, Špela; Oliveira, Teresa; Belotti, Elisa; Bufka, Luděk; Černe, Rok & Heurich, Marco Dietmar [Show all 8 contributors for this article] (2024). Revealing functional responses in habitat selection of rocky features and rugged terrain by Eurasian lynx (Lynx lynx) using LiDAR data. Landscape Ecology. ISSN 0921-2973. 39. doi: 10.1007/s10980-024-01923-y. Full text in Research Archive Show summary

  Context Many carnivores are attracted to rugged terrain, rocky areas, and conspicuous relief features. However, most of the previous research is limited to general topographical habitat characteristics and rarely consider the effects of microhabitat characteristics. Objectives We used the Eurasian lynx (Lynx lynx) as a model species to investigate the effects of microhabitat characteristics and human infrastructure on habitat selection. We also tested whether there is evidence for a functional response in habitat selection across a large gradient of habitat availability. Methods We developed a new approach for detecting rocky outcrops from airborne LiDAR data. In combination with other remote sensing techniques and GPS-telemetry data, we assessed lynx habitat selection and functional responses across two geologically contrasting areas in Europe. Results We detected > 1 million rocky outcrops and confirmed their strong selection by lynx. Lynx also selected steep, rugged, and rocky areas, especially for day-resting sites. Furthermore, lynx avoided paths during the day but selected them and other linear anthropogenic infrastructure during the night, indicating the behaviour-specific impact of human infrastructure. We also observed a functional response in the selection of rocky and rugged areas, as lynx’ selection of such habitats increased with their lower availability. This highlights the importance of preserving such terrains, especially when they are rare in a landscape. Conclusions Our results highlight the importance of incorporating remote sensing techniques and data on microhabitat features in animal habitat selection research. We also recommend caution when developing new infrastructure for human recreation or promoting its use near geomorphological features and in rugged terrain.

• Rehbein, Steffen; Velling, Marc; Visser, Martin; Heurich, Marco Dietmar & Hamel, Dietmar (2024). Successful establishment of Ashworthius sidemi in red deer (Cervus elaphus) in Germany, with a summary of worldwide A. sidemi records. European Journal of Wildlife Research. ISSN 1612-4642. 71(1). doi: 10.1007/s10344-024-01882-4. Full text in Research Archive Show summary

  Ashworthius sidemi is a nematode characteristic for cervids native to the mainland of eastern Asia like particular subspecies of sika deer (Cervus nippon) including Dybowski’s sika deer (C. n. hortulorum). With the translocation of so-called ʻmainlandʼ sika deer and/or Maral deer (C. canadensis sibiricus) that had previously been kept with Dybowski’s sika deer in deer farms in the former Soviet Union, the parasite was transferred to Europe and reported in the 1970s from current Czechia, central Russia and the Ukraine. The fall of the ‘Iron Curtain’ in the 1990s allowed for the exchange of deer between neighboring Bohemia, Czechia and Bavaria, Germany, which was associated with the introduction of the invasive very pathogenic giant liver fluke, Fascioloides magna, to Bavaria and the establishment of sika deer. Studies on the epidemiology of fascioloidosis prompted the characterization of the overall helminth fauna of red deer from two localities in the border region to Bohemia - Upper Palatinate Forest (13 deer, collected 2011 to 2013) and Bavarian Forest National Park (eight deer, collected 2022) - where F. magna was first confirmed in 2011 and in 2019, respectively. The nematode spectrum was overall characterized by cervid-adapted species with polymorphic ostertagids dominating the abomasal nematode community. Among the 15 species of nematodes recovered from the gastrointestinal tract, however, was the Haemonchus-like A. sidemi which has been recorded for the first time in Germany. Noticeably, A. sidemi was the only nematode that was found in all animals with counts (range, 15 to 765) comparable to the cervid-adapted ostertagid species and made up approximately 25% of the total gastrointestinal nematode burden of the red deer from both areas. In addition to gastrointestinal nematodes, Setaria cervi, F. magna, and Dictyocaulus, Varestrongylus and Elaphostrongylus species infections were recorded. In conclusion, this work shows that A. sidemi established in red deer in Germany and forms a substantial portion of the gastrointestinal nematode burden. Further studies are encouraged to monitor the spread of A. sidemi and to better understand its role in the parasite community of wild ungulates in Europe and the relevance of the infection for both wild and domestic ruminants. To facilitate future research on A. sidemi, a synopsis of references on the worldwide occurrence and host range of the nematode is provided.

• Mangold, Max; Schwietering, Arne; Zink, Julia; Steinbauer, Manuel & Heurich, Marco Dietmar (2024). The digitalization of outdoor recreation: Global perspectives on the opportunities and challenges for protected area management. Journal of Environmental Management (JEM). ISSN 0301-4797. 352. doi: 10.1016/j.jenvman.2024.120108. Full text in Research Archive Show summary

  The increasing popularity of digital media among protected area visitors poses challenges to protected area management. It alters the way visitors move and behave in the area, potentially increasing disturbance of nature, and it might also affect their expectation prior to the visit and their reflection on it. Simultaneously, digital media allow protected area managers to develop and implement new methods of digital visitor management (DVM). This may help to avoid conflicts and ensure compliance with rules and regulations and may have much further reaching positive consequences. Based on an online survey across 131 parks in 46 countries covering all continents, this study examined for the first time how protected areas view DVM. The results showed that the majority of park managers see digitalization as an opportunity, with 91% agreeing that it enables them to reach larger numbers of visitors and to provide real-time information. The advantage of integrating digital media into visitor monitoring was recognized. However, some park managers perceived digitalization as problematic, with 42% agreeing that it increases visitor load in sensitive areas and 40% agreeing that it leads to more off-trail activity. A clear majority of the respondents (61–91%) saw the proposed methods of DVM as effective or very effective. Accordingly, 70% of them envisioned using DVM in the future. Our findings suggest that the effects of digitalization in outdoor recreation are largely similar across the globe, with no significant influence of economic status or region. They offer insights into the potential of DVM for protected area management, but also its main obstacles. Adoption will be facilitated by increasing staff and funding for DVM. Additionally, knowledge exchange between protected areas can ease the successful implementation of new digital tools.

• Zink, Julia; Mangold, Max; Porst, Florian; Steinbauer, Manuel & Heurich, Marco Dietmar (2024). Towards a digital ranger: Using data from outdoor platforms to detect rule violations in protected areas and improve visitor management. Journal of Outdoor Recreation and Tourism. ISSN 2213-0780. 48. doi: 10.1016/j.jort.2024.100835. Full text in Research Archive
• Yuh, Yisa Ginath; N’Goran, Kouamé Paul; Kross, Angela; Heurich, Marco Dietmar; Matthews, H. Damon & Turner, Sarah E. (2024). Monitoring forest cover and land use change in the Congo Basin under IPCC climate change scenarios. PLOS ONE. 19(12). doi: 10.1371/journal.pone.0311816. Full text in Research Archive Show summary

  The Congo Basin tropical forests are home to many endemic and endangered species, and a global hotspot for forest fragmentation and loss. Yet, little has been done to document the region’s rapid deforestation, assess its effects and consequences, or project future forest cover loss to aid in effective planning. Here we applied the Random Forest (RF) supervised classification algorithm in Google Earth Engine (GEE) to map and quantify decadal changes in forest cover and land use (LCLU) in the Congo Basin between 1990 and 2020. We cross-validated our LCLU maps with existing global land cover products, and projected our validated results to 2050 under three climate change scenarios, using the Multiperceptron Artificial Neural Network and Markov chain algorithms of the Idrissi Land Change modeller from TerrSet. We found that, over 5.2% (215,938 km2), 1.2% (50,046 km2), and a 2.1% (86,658 km2) of dense forest cover were lost in the Congo Basin between 1990–2000, 2000–2010, and 2010–2020, totaling approximately 8.5% (352,642 km2) loss estimated between 1990–2020. For the period 2020–2050, we estimated a projected 3.7–4.0% (174,860–204,161 km2) loss in dense forest cover under all three climate change scenarios (i.e., 174,860 km2 loss projected for SSP1-2.6, 199,608 km2 for SSP2-4.5, and 204,161 km2 for SSP5-8.5), suggesting that approximately 12.3–12.6% (527,502 km2–556,803 km2) of dense forest cover could be lost over a 60-year period (1990–2050). Our study represents a novel application of spatial modeling tools and Machine Learning algorithms for assessing long-term deforestation and forest degradation within the Congo Basin, under human population growth and IPCC climate change scenarios. We provide spatial and quantitative results required for supporting long-term deforestation and forest degradation monitoring within Congo Basin countries, especially under the United Nations Framework Convention on Climate Change (UNFCCC) REDD+ (Reduce Emissions from Deforestation and Forest Degradation) program.

• Felipe-Lucia, María R.; Frutos, Ángel de; Crouzat, Emilie; Grescho, Volker; Heuschele, Jonna M. & Marselle, Melissa [Show all 15 contributors for this article] (2024). Differences in the experience of cultural ecosystem services in mountain protected areas by clusters of visitors. Ecosystem Services. 70. doi: 10.1016/j.ecoser.2024.101663. Full text in Research Archive Show summary

  Protected Areas contribute to the conservation of nature with associated cultural ecosystem services (CES) and values, such as recreational and educational opportunities, wildlife observation, scenic beauty, inspiration and sense of belonging. Informed management of Protected Areas needs to consider the distinct use and preferences for CES of different types of visitors to increase opportunities for nature experience while avoiding conflicts with biodiversity conservation. Therefore, it is important to understand the linkages between visitor characteristics and their demand for specific sets of CES, particularly in fragile mountain ecosystems. Here we do so by combining information from individual on-site surveys and participatory mapping of visitors in four European mountain Protected Areas. We analysed visitors’ frequency of use of eight CES and their socio-demographic information, identifying three clusters of visitors. We also assessed the spatial distribution of CES locations used by each visitor cluster. Our results highlight strong differences between clusters both in the most frequently experienced CES and in the spatial location where those CES were experienced. We suggest that a better understanding of visitors regarding the way they experience nature is relevant for the environmental management of mountain Protected Areas and their surroundings.

• Florescu, Gabriela; Tinner, Willy; Feurdean, Angelica; Finsinger, Walter; Kuneš, Petr & Vondrák, Daniel [Show all 11 contributors for this article] (2024). Forest composition and density shaped long-term fire regimes and catchment-lake interactions in the temperate-mixed mountain forests of Central Europe. Forest Ecology and Management. ISSN 0378-1127. 572. doi: 10.1016/j.foreco.2024.122267. Full text in Research Archive Show summary

  The projected rise in fire activity due to climate change challenges forest conservation efforts worldwide. Current non-intervention approaches, which rely on natural processes for ecosystem conservation, often overlook palaeoecological data depicting long-term, local interactions between fire regime components, forest structure and composition, soil, aquatic environment and anthropogenic disturbance. To explore whether palaeoecological information supports non-intervention strategies in the Picea abies – Fagus sylvatica – Abies alba closed temperate mountain forest under future fire risks, we conducted a multi-proxy, retrospective analysis (charcoal morphology, pollen, plant macro-remains, sedimentology, palaeoclimate models) on a Holocene lacustrine archive located in the Bavarian Forest National Park, Germany. Results show that climate shifts directly induced vegetation reorganizations and fire regime changes around 11.1, 9.3 and 7–6 ka BP, and gradually allowed the expansion of closed mixed forests dominated by the late successional Picea abies – Fagus sylvatica - Abies alba under a remarkably stable, low-fire environment. We emphasize the possible role of shade-related traits of these species as key bottom-up drivers of biomass burning over the past 6000 years likely due to their effects on microclimate, offsetting the species-specific fire traits. Although these forests tolerate low-severity surface fire, more subtle impacts were identified at the level of soil cover and lacustrine environment. First, our data demonstrate that lake browning processes developed naturally since the Early Holocene with the progression of chemical weathering and podzol formation, but an ecological threshold due to browning intensification was crossed ca. 6000 years ago, under maximum forest density and in the absence of fire disturbance. Second, fire likely reduced lake water browning and soil podzolisation processes by mineral erosion and the decrease in litter and soil organic matter due to direct burning or indirect aeration. Soil and aquatic ecosystem components appeared highly interconnected and responded even to low disturbance severities. Consequently, these components may react more sensitively to the predicted increase in fire frequency and severity, with yet unknown ripple effects on the forest ecosystem resilience. Given the critical role of the Picea abies - Fagus sylvatica - Abies alba closed-canopy forests in shaping the microclimate and catchment-lake interactions, our study suggests that non-intervention strategies are suitable for preserving ecosystem stability in these types of forests. By promoting natural recovery of shade-tolerant tree species and minimizing direct anthropogenic impacts, this approach would protect the soil, regulate erosion and delivery of soil organic substances, and potentially mitigate the effects of climate change on fire hazard and on individual forest tree species.

• Oliveira, Teresa; Mattisson, Jenny; Vogt, Kristina; Linnell, John Durrus; Odden, John & Oeser, Julian [Show all 37 contributors for this article] (2024). Ecological and intrinsic drivers of foraging parameters of Eurasian lynx at a continental scale. Journal of Animal Ecology. ISSN 0021-8790. 94, p. 154–167. doi: 10.1111/1365-2656.14228. Full text in Research Archive Show summary

  1. 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. 2. 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. 3. We found that inter-kill intervals and handling times varied between populations, social status and in different se

• Fleischer, Ramona; Velling, Marc; Peters, Wibke Erika Brigitta; Peterka, Tomáš; Franke, Frederik & Vymyslická, Pavla Jůnková [Show all 9 contributors for this article] (2024). Invasive Fascioloides magna infections impact gut microbiota in a definitive host in Europe. International Journal for Parasitology: Parasites and Wildlife. 25. doi: 10.1016/j.ijppaw.2024.101024. Full text in Research Archive Show summary

  Invasive parasites that expand their natural range can be a threat to wildlife biodiversity and may pose a health risk to non-adapted, naive host species. The invasive giant liver fluke, Fascioloides magna, native to North America, has extended its range in Europe and uses mainly red deer (Cervus elaphus) as definitive hosts. The penetration of the intestinal barrier by the young flukes to reach the liver via the abdominal cavity as well as the release of fluke metabolism products and excreta with the bile and/or changes in the microbial community of the biliary system may enable the translocation of intestinal bacteria across the intestinal barrier and, in turn, could be associated with inflammation and changes in the intestinal bacterial community. The gut commensal community plays a key role in host nutrition and interacts with cells of the immune system to maintain host health. For this study, the gut bacterial community of red deer infected with F. magna and of non-infected red deer from one of the largest forest ecosystems in Central Europe, located on the border between the Czech Republic and Germany, was investigated. The individual fluke burden was associated with changes in the gut microbial composition of the gut of infected individuals, whereas the diversity and composition of the gut bacteria were only slightly different between fluke-infected and uninfected deer. Several bacterial taxa at the genus level were unique to individuals carrying either one or many liver flukes. Our results suggest that the microbiota of red deer is stable to perturbation by low numbers of F. magna. However, a larger parasite burden may cause changes in the gut microbial composition in definitive hosts implying that non-invasive fecal microbiome assessments could serve as indicator for wildlife health monitoring.

• Atmeh, Kamal; Bonenfant, Christophe; Gaillard, Jean-Michel; Garel, Mathieu; Hewison, A. J. Mark & Marchand, Pascal [Show all 74 contributors for this article] (2024). Neonatal antipredator tactics shape female movement patterns in large herbivores. Nature Ecology and Evolution. 9, p. 142–152. doi: 10.1038/s41559-024-02565-8. Full text in Research Archive Show summary

  Caring for newborn ofspring hampers resource acquisition of mammalian females, curbing their ability to meet the high energy expenditure of early lactation. Newborns are particularly vulnerable, and, among the large herbivores, ungulates have evolved a continuum of neonatal antipredator tactics, ranging from immobile hider (such as roe deer fawns or impala calves) to highly mobile follower ofspring (such as reindeer calves or chamois kids). How these tactics constrain female movements around parturition is unknown, particularly within the current context of increasing habitat fragmentation and earlier plant phenology caused by global warming. Here, using a comparative analysis across 54 populations of 23 species of large herbivores from 5 ungulate families (Bovidae, Cervidae, Equidae, Antilocapridae and Girafdae), we show that mothers adjust their movements to variation in resource productivity and heterogeneity according to their ofspring’s neonatal tactic. Mothers with hider ofspring are unable to exploit environments where the variability of resources occurs at a broad scale, which might alter resource allocation compared with mothers with follower ofspring. Our fndings reveal that the overlooked neonatal tactic plays a key role for predicting how species are coping with environmental variation.

• Sani-Mohammed, Abubakar; Yao, Wei; Wong, Tsz Chung; Fekry, Reda & Heurich, Marco Dietmar (2024). Characterizing Forest Plot Decay Levels Based on Leaf Area Index, Gap Fraction, and L-Moments from Airborne LiDAR. Remote Sensing. 16(15). doi: 10.3390/rs16152824. Full text in Research Archive Show summary

  Effective forest management is essential for mitigating climate change effects. This is why understanding forest growth dynamics is critical for its sustainable management. Thus, characterizing forest plot deadwood levels is vital for understanding forest dynamics, and for assessments of biomass, carbon stock, and biodiversity. For the first time, this study used the leaf area index (LAI) and L-moments to characterize and model forest plot deadwood levels in the Bavarian Forest National Park from airborne laser scanning (ALS) data. This study proposes methods that can be tested for forests, especially those in temperate climates with frequent cloud coverage and limited access. The proposed method is practically significant for effective planning and management of forest resources. First, plot decay levels were characterized based on their canopy leaf area density (LAD). Then, the deadwood levels were modeled to assess the relationships between the vegetation area index (VAI), gap fraction (GF), and the third L-moment ratio (T3). Finally, we tested the rule-based methods for classifying plot decay levels based on their biophysical structures. Our results per the LAD vertical profiles clearly showed the declining levels of decay from Level 1 to 5. Our findings from the models indicate that at a 95% confidence interval, 96% of the variation in GF was explained by the VAI with a significant negative association (VAIslope = −0.047; R2 = 0.96; (p < 0.001)), while the VAI explained 92% of the variation in T3 with a significant negative association (VAIslope = −0.50; R2 = 0.92; (p < 0.001)). Testing the rule-based methods, we found that the first rule (Lcv = 0.5) classified Levels 1 and 2 at (Lcv < 0.5) against Levels 3 to 5 at (Lcv > 0.5). However, the second rule (Lskew = 0) classified Level 1 (healthy plots) as closed canopy areas (Lskew < 0) against Levels 2 to 5 (deadwood) as open canopy areas (Lskew > 0). This approach is simple and more convenient for forest managers to exploit for mapping large forest gap areas for planning and managing forest resources for improved and effective forest management.

• Ferry, Nicolas; Dupont, Pierre; Bender, Andreas & Heurich, Marco Dietmar (2024). Introducing recurrent event analyses to assess species interactions based on camera-trap data: A comparison with time-to-first-event approaches. Methods in Ecology and Evolution. 15(7), p. 1233–1246. doi: 10.1111/2041-210X.14338. Full text in Research Archive Show summary

  Camera-trap surveys are increasingly used to assess species interactions, with a growing focus on proximate co-occurrence, the conditional probability of one species occurring after another within a given time window. However, existing time-to-first-event models, commonly employed for this purpose, suffer from multiple limitations. For instance, they cannot fully quantify the interaction strength, that is how strongly one species affects the occurrence probability of another, nor the duration of this effect, nor identify the directionality of the interaction. We propose reframing the question in terms of recurrent event analysis, which enables the use of a rich set of techniques to provide more information about the data-generating process. In particular, we use the piece-wise exponential additive mixed model (PAMM) to take into account all available information (including recurrent occurrences of species) and to estimate the non-linear temporal dynamics of the visitation rate of a species after the occurrence of another. As the estimation is performed within the framework of generalized additive models, it offers a rich, robust and established inferential toolbox. We evaluated PAMM's performance in estimating species interactions through a simulation study involving two species under various scenarios of attraction or repulsion, with and without imperfect detection. Additionally, we compared the PAMM to six time-to-first-event methods commonly used in camera-trap studies and illustrated its application with real data. PAMMs outperformed the other methods in terms of statistical power, output interpretability and ability to disentangle interactions. The robust performance of PAMMs underscores their potential as a valuable tool for studying species interactions based on camera-trap data. To facilitate its adoption, we present the new package ctrecurrent and provide a reproducible workflow from data preparation to model fitting.

• Carpentier, Cecile Agnes Edith; Heurich, Marco Dietmar; Gimenez, Olivier; Devineau, Olivier & Linnell, John Durrus (2024). Cumulative mortality effects on roe deer population dynamics in the boreal forest: Searching for pathways of population persistence. Global Ecology and Conservation. 56. doi: 10.1016/j.gecco.2024.e03318. Full text in Research Archive Show summary

  Ungulate populations can exhibit various growth patterns, which are influenced by factors such as predation and resource availability. Favourable environments can lead to irruptive growth, resulting in resource depletion. However, additional pressures from predation, and hunting can potentially impact population development leading to declines or even local extinctions. This study uses simulation models to explore the potential impact of multiple mortality sources on roe deer populations. We develop an age-structured, two-sex demographic matrix model for roe deer, which we parameterise with empirical demographic estimates obtained from published studies in Norway. We develop scenarios to assess the influence of mortality sources such as hunting, predation by lynx and red foxes, and environmental stochasticity on roe deer population dynamics. When simulating favourable environments without predation, roe deer populations tended to erupt due to the species’ rapid reproductive capacity. However, additional sources of mortality, such as predation or harvest, lead to severe population declines, and even to quasiextinction, especially when occurring in combination. Environmental stochasticity such as periodic severe winters with heavy snowfall reduces the growth rate and population densities even further. On the other hand, accounting for some form of spatial heterogeneity through immigration and refuges stabilised populations, with a reduced risk of quasi-extinction. Our results provide meaningful insights into the properties of this system allow implications for the management and identify areas where further exploration is needed. Additive mortality Matrix model Population dynamics Predator-prey Roe deer (Capreolus capreolus) Wildlife management

• Dersch, S.; Schöttl, A.; Krzystek, P. & Heurich, Marco Dietmar (2024). Semi-supervised multi-class tree crown delineation using aerial multispectral imagery and lidar data. ISPRS Journal of Photogrammetry and Remote Sensing (P&RS). ISSN 0924-2716. 216, p. 154–167. doi: 10.1016/j.isprsjprs.2024.07.032. Full text in Research Archive Show summary

  The segmentation of individual trees based on deep learning is more accurate than conventional meth- ods. However, a sufficient amount of training data is mandatory to leverage the accuracy potential of deep learning-based approaches. Semi-supervised learning techniques, by contrast, can help simplify the time-consuming labelling process. In this study, we introduce a new semi-supervised tree segmen- tation approach for the precise delineation and classification of individual trees that takes advantage of pre-clustered tree training labels. Specifically, the instance segmentation Mask R-CNN is combined with the normalized cut clustering method, which is applied to lidar point clouds. The study areas were located in the Bavarian Forest National Park, southeast Germany, where the tree composition includes coniferous, deciduous and mixed forest. Important tree species are European beech (Fagus sylvatica), Norway spruce (Picea abies) and silver fir (Abies alba). Multispectral image data with a ground sample distance of 10 cm and laser scanning data with a point density of approximately 55 points/m2 were acquired in June 2017. From the laser scanning data, three-channel images with a resolution of 10 cm were generated. The models were tested in seven reference plots in the national park, with a total of 516 trees measured on the ground. When the color infrared images were used, the experiments demonstrated that the Mask R-CNN models, trained with the tree labels generated through lidar-based clustering, yielded mean F1 scores of 79 % that were up to 18 % higher than those of the normalized cut baseline method and thus significantly improved. Similarly, the mean over- all accuracy of the classification results for the coniferous, deciduous, and standing deadwood tree groups was 96 % and enhanced by up to 6 % compared with the baseline classification approach. The experiments with lidar-based images yielded slightly worse (1–2 %) results both for segmentation and for classification. Our study demonstrates the utility of this simplified training data preparation pro- cedure, which leads to models trained with significantly larger amounts of data than is feasible with with manual labelling. The accuracy improvement of up to 18 % in terms of the F1 score is further evidence of its advantages.

• Pelsmaeker, Nicolas De; Ferry, Nicolas; Stiegler, Jonas; Selva, Nuria; Hoermann, Christian von & Müller, Jörg [Show all 7 contributors for this article] (2024). Seasonal variability of scavenger visitations is independent of carrion predictability. Basic and Applied Ecology. ISSN 1439-1791. 79, p. 57–64. doi: 10.1016/j.baae.2024.05.005. Full text in Research Archive Show summary

  In temperate regions, larger mammalian carrion naturally occurs in terrestrial landscapes as a pulsed resource towards the end of the winter through enhanced ungulate mortality due to starvation or exhaustion. The return of large carnivores in Central Europe provides carrion more equally throughout the year and the active enhancement of carrion for biodiversity by game managers has increased, raising the question of how different scavengers respond to the temporal variation in carrion supply. To address this question, we experimentally deployed 106 cervid carcasses throughout the year in a temperate forest of south-eastern Germany on two types of plots: permanent (i.e., site with multiple subsequent deployments) or random (i.e., site with unique deployment), and reported vertebrate scavenger visitations by camera trapping. Deployment on random or permanent sites did not affect carrion use by any single species. Generalized additive modelling revealed that vertebrate scavenging peaked in the winter season and summer independent of carrion supply. Still, different scavenger species showed different temporal patterns. While wild boar as ungulate omnivores did not display any seasonal patterns, avian scavengers showed significant variation in visitation rates. The mesopredator red fox consumed carrion significantly more often from late winter to summer, while pine marten was present at carrion only during winter. Finally, the specialist large carnivore Eurasian lynx, visited carrion sites most frequently in late winter and early spring. Our results suggest that global warming might impact some groups of vertebrate scavengers more strongly than others by reducing carrion availability in late winter, while returning carnivores could mitigate these impacts.

• Schindler, Frank; Steinhage, Volker; Calkoen, Suzanne T.S van Beeck & Heurich, Marco Dietmar (2024). Action Detection for Wildlife Monitoring with Camera Traps Based on Segmentation with Filtering of Tracklets (SWIFT) and Mask-Guided Action Recognition (MAROON). Applied Sciences. 14(2). doi: 10.3390/app14020514. Full text in Research Archive Show summary

  Behavioral analysis of animals in the wild plays an important role for ecological research and conservation and has been mostly performed by researchers. We introduce an action detection approach that automates this process by detecting animals and performing action recognition on the detected animals in camera trap videos. Our action detection approach is based on SWIFT (segmentation with filtering of tracklets), which we have already shown to successfully detect and track animals in wildlife videos, and MAROON (mask-guided action recognition), an action recognition network that we are introducing here. The basic ideas of MAROON are the exploitation of the instance masks detected by SWIFT and a triple-stream network. The instance masks enable more accurate action recognition, especially if multiple animals appear in a video at the same time. The triple-stream approach extracts features for the motion and appearance of the animal. We evaluate the quality of our action recognition on two self-generated datasets, from an animal enclosure and from the wild. These datasets contain videos of red deer, fallow deer and roe deer, recorded both during the day and night. MAROON improves the action recognition accuracy compared to other state-of-the-art approaches by an average of 10 percentage points on all analyzed datasets and achieves an accuracy of 69.16% on the Rolandseck Daylight dataset, in which 11 different action classes occur. Our action detection system makes it possible todrasticallyreduce the manual work of ecologists and at the same time gain new insights through standardized results.

• Rietz, Janine; Ischebeck, Sophia; Conraths, Franz J.; Probst, Carolina; Zedrosser, Andreas & Fiderer, Christian [Show all 10 contributors for this article] (2024). Scavenger-induced scattering of wild boar carcasses over large distances and its implications for disease management. Journal of Environmental Management (JEM). ISSN 0301-4797. 365. doi: 10.1016/j.jenvman.2024.121554. Full text in Research Archive Show summary

  Vertebrate scavengers provide essential ecosystem services such as accelerating carrion decomposition by consuming carcasses, exposing tissues to microbial and invertebrate decomposers, and recycling nutrients back into the ecosystem. Some scavengers do not consume carcasses on site but rather scatter their remains in the surroundings, which might have important implications for nutrient transport, forensic investigations and the spread of diseases such as African Swine Fever. However, only a few studies have investigated and measured the scatter distances. Using wild boar (Sus scrofa) carcasses and limbs, we monitored scavenging behavior and measured scatter distances of mammals. We placed 20 carcasses (up to 25 kg) and 21 separate limbs equipped with very high frequency (VHF) transmitters and monitored scavenger activity using camera traps in a mountainous region in southeast Germany. Except for one carcass, all other carcasses and limbs were scattered. We measured 72 scatter distances (of 89 scattering events; mean = 232 m, maximum = 1250 m), of which 75% were dispersed up to 407 m. Scavengers moved scattered pieces into denser vegetation compared to the half-open vegetation at provisioning sites. Red foxes (Vulpes vulpes) were the most common scavenger species, contributing to 72 scattering events (58 measured scatter distances). Our results provide evidence of scatter distances farther than previously assumed and have far-reaching implications for disease management or forensic investigations, as the broader surroundings of carcasses must be included in search efforts to remove infectious material or relevant body parts for forensic analysis.

• Calkoen, Suzzane T S van Beeck; Milch, Jérôme; Kupferschmid, Andrea D.; Fiderer, Christian & Heurich, Marco Dietmar (2023). A guide for selecting the appropriate plot design to measure ungulate browsing. Forest Ecosystems. 10. doi: 10.1016/j.fecs.2023.100147. Full text in Research Archive Show summary

  Ungulate browsing often impairs tree regeneration, thus preventing the achievement of economic or conservation goals. Forest ungulate management would thus benefit from a practical decision tool that facilitates method selection from a wide range of monitoring methods and indicators currently available. In this study, we first provide an overview of the different browsing-impact monitoring methods and indicators currently applied. We then present a newly developed decision matrix for method evaluation that can assist forest stakeholders in choosing the browsing-impact monitoring method best suited to their needs, based on the selected indicators. The first step involved two separate literature reviews to create an overview of the currently applied methods and to select the indicators best suited for measuring browsing impact. Three types of indicator groups with their respective parameters were considered important for method evaluation: browsing indicators (e.g. regeneration density, browsing incidents), performance indicators (e.g. expense, expertise) and data quality indicators (e.g. susceptibility to measurement errors). Subsequently, all parameters defined within each indicator group were categorised and a grade was assigned to each category. To create the final method-indicator matrix, each browsing-impact monitoring method received a grade for each parameter within all indicator groups, reflecting the specific advantages and disadvantages of implementing the respective parameter within a specific method. The utility of the matrix in selecting the most suitable monitoring method was then demonstrated using the example of Germany's national parks. Based on the weights added to the method-indicator matrix, as defined by national park representatives, and considering local requirements the nearest-tree method was favoured over the other two methods. This newly developed matrix provides a more scientific objectification of ungulate browsing-impact measures and can be easily used by forest managers to address their own requirements, based on a consideration of the advantages and disadvantages of the included methods.

• Calkoen, Suzanne T. S. van Beeck; Kuijper, Dries P. J.; Apollonio, Marco; Blondel, Lena; Dormann, Carsten F. & Storch, Ilse [Show all 7 contributors for this article] (2023). Numerical top-down effects on red deer (Cervus elaphus) are mainly shaped by humans rather than large carnivores across Europe. Journal of Applied Ecology. ISSN 0021-8901. 60(12), p. 2625–2635. doi: 10.1111/1365-2664.14526. Full text in Research Archive Show summary

  Terrestrial ecosystems are shaped by interacting top-down and bottom-up processes, with the magnitude of top-down control by large carnivores largely depending on environmental productivity. While carnivore-induced numerical effects on ungulate prey populations have been demonstrated in large, relatively undisturbed ecosystems, whether large carnivores can play a similar role in more human-dominated systems is a clear knowledge gap. As humans influence both predator and prey in a variety of ways, the ecological impacts of large carnivores can be largely modified. We quantified the interactive effects of human activities and large carnivore presence on red deer (Cervus elaphus) population density and how their impacts interacted and varied with environmental productivity. Data on red deer density were collected based on a literature survey encompassing 492 study sites across 28 European countries. Variation in density across study sites was analysed using a generalized additive model in which productivity, carnivore presence (grey wolf, European lynx, Brown bear), human activities (hunting, intensity of human land-use activity), site protection status and climatic variables served as predictors. The results showed that a reduction in deer density only occurred when wolf, lynx and bear co-occurred within the same site. In the absence of large carnivores, red deer density varied along a productivity gradient without a clear pattern. Although a linear relationship with productivity in the presence of all three large carnivore species was found, this was not statistically significant. Moreover, hunting by humans had a stronger effect than the presence of all large carnivores in reducing red deer density and red deer density increased with increasing intensity of human land use, with stronger large carnivore effects (all three carnivore species present) at sites with low human land-use activities. Synthesis and applications. This study provides evidence for the dominant role played by humans (i.e. hunting, land-use activities) relative to large carnivores in reducing red deer density across European human-dominated landscapes. These findings suggest that when we would like large carnivores to exert numeric effects, we should focus on minimizing human impacts to allow the ecological impacts of large carnivores on ecosystem functioning.

• Bacon, Sam; Smith, Adam F.; Döringer, Stefanie; Bečka, Pavel; Hußlein, Maria & Porst, Florian [Show all 8 contributors for this article] (2023). Visitors to national parks show positive attitudes towards recolonising wolves in the Bohemian Forest Ecosystem. Biological Conservation. ISSN 0006-3207. 288. doi: 10.1016/j.biocon.2023.110349. Full text in Research Archive
• Wielgus, Elodie; Klamm, Alisa; Conraths, Franz J.; Dormann, Carsten F.; Henrich, Maik & Kronthaler, Franz [Show all 7 contributors for this article] (2023). First-Passage Time Analysis Based on GPS Data Offers a New Approach to Estimate Restricted Zones for the Management of Infectious Diseases in Wildlife: A Case Study Using the Example of African Swine Fever. Transboundary and Emerging Diseases. ISSN 1865-1674. 2023. doi: 10.1155/2023/4024083. Full text in Research Archive Show summary

  An essential part of any disease containment and eradication policy is the implementation of restricted zones, but determining the appropriate size of these zones can be challenging for managers. We designed a new method, based on animal movement, to help assess how large restricted zones should be after a spontaneous outbreak to successfully control infectious diseases in wildlife. Our approach uses first-passage time (FPT) analysis and Cox proportional hazard (CPH) models to calculate and compare the risk of an animal leaving different-sized areas. We illustrate our approach using the example of the African swine fever (ASF) virus and its wild pig reservoir host species, the wild boar (Sus scrofa), and we investigate the feasibility of applying this method to other systems. Using GPS data from 57 wild boar living in the Hainich National Park, Germany, we calculate the time spent by each individual in areas of different sizes using FPT analysis. We apply CPH models on the derived data to compare the risk of leaving areas of different sizes and to assess the effects of season and the sex of the wild boar on the risk of leaving. We conduct survival analyses to estimate the risk of leaving an area over time. Our results indicate that the risk of leaving an area decreases exponentially by 10% for each 100 m increase in radius size so that the differences were more pronounced for small sizes. Furthermore, the probability of leaving increases exponentially with time. Wild boar had a similar risk of leaving an area of a given size throughout the year, except in spring and winter, when females had a much lower risk of leaving. Our findings are in agreement with the literature on wild boar movement, further validating our method, and repeated analyses with location data resampled at different rates gave similar results. Our results may be applicable only to our study area, but they demonstrate the applicability of the proposed method to any ecosystem where wild boar populations are likely to be infected with ASF and where restricted zones should be established accordingly. The outlined approach relies solely on the analysis of movement data and provides a useful tool to determine the optimal size of restricted zones. It can also be applied to future outbreaks of other diseases.

• Kühl, Hjalmar S.; Buckland, Stephen T.; Henrich, Maik; Howe, Eric & Heurich, Marco Dietmar (2023). Estimating effective survey duration in camera trap distance sampling surveys. Ecology and Evolution. 13(10). doi: 10.1002/ece3.10599. Full text in Research Archive Show summary

  Among other approaches, camera trap distance sampling (CTDS) is used to estimate animal abundance from unmarked populations. It was formulated for videos and observation distances are measured at predetermined ‘snapshot moments’. Surveys recording still images with passive infrared motion sensors suffer from frequent periods where animals are not photographed, either because of technical delays before the camera can be triggered again (i.e. ‘camera recovery time’) or because they remain stationary and do not immediately retrigger the camera following camera recovery time (i.e. ‘retrigger delays’). These effects need to be considered when calculating temporal survey effort to avoid downwardly biased abundance estimates. Here, we extend the CTDS model for passive infrared motion sensor recording of single images or short photo series. We propose estimating ‘mean time intervals between triggers’ as combined mean camera recovery time and mean retrigger delays from the time interval distribution of pairs of consecutive pictures, using a Gamma and Exponential function, respectively. We apply the approach to survey data on red deer, roe deer and wild boar. Mean time intervals between triggers were very similar when estimated empirically and when derived from the model-based approach. Depending on truncation times (i.e. the time interval between consecutive pictures beyond which data are discarded) and species, we estimated mean time intervals between retriggers between 8.28 and 15.05 s. Using a predefined snapshot interval, not accounting for these intervals, would lead to underestimated density by up to 96% due to overestimated temporal survey effort. The proposed approach is applicable to any taxa surveyed with camera traps. As programming of cameras to record still images is often preferred over video recording due to reduced consumption of energy and memory, we expect this approach to find broad application, also for other camera trap methods than CTDS.

• Zong, Xin; Wang, Tiejun; Skidmore, Andrew K. & Heurich, Marco Dietmar (2023). Habitat visibility affects the behavioral response of a large herbivore to human disturbance in forest landscapes. Journal of Environmental Management (JEM). ISSN 0301-4797. 348. doi: 10.1016/j.jenvman.2023.119244. Full text in Research Archive
• Hoermann, Christian von; Benbow, M. Eric; Rottler-Hoermann, Ann-Marie; Lackner, Tomáš; Sommer, David & Receveur, Joseph P. [Show all 9 contributors for this article] (2023). Factors influencing carrion communities are only partially consistent with those of deadwood necromass. Oecologia. ISSN 0029-8549. 201(2), p. 537–547. doi: 10.1007/s00442-023-05327-8. Full text in Research Archive Show summary

  Research on decomposer communities has traditionally focused on plant litter or deadwood. Even though carrion forms highly nutrient-rich necromass that enhance ecosystem heterogeneity, the factors infuencing saprophytic communities remain largely unknown. For deadwood, experiments have shown that diferent drivers determine beetles (i.e., decay stage, microclimate, and space), fungi (i.e., decay stage and tree species) and bacteria (decay stage only) assemblages. To test the hypothesis that similar factors also structure carrion communities, we sampled 29 carcasses exposed for 30 days that included Cervus elaphus (N=6), Capreolus capreolus (N=18), and Vulpes vulpes (N=5) in a mountain forest throughout decomposition. Beetles were collected with pitfall traps, while microbial communities were characterized using amplicon sequencing. Assemblages were determined with a focus from rare to dominant species using Hill numbers. With increasing focus on dominant species, the relative importance of carcass identity on beetles and space on bacteria increased, while only succession and microclimate remained relevant for fungi. For beetle and bacteria with focus on dominant species, host identity was more important than microclimate, which is in marked contrast to deadwood. We conclude that factors infuencing carrion saprophytic assemblages show some consistency, but also diferences from those of deadwood assemblages, suggesting that short-lived carrion and long-lasting deadwood both provide a resource pulse with diferent adaptions in insects and microbes. As with deadwood, a high diversity of carcass species under multiple decay stages and diferent microclimates support a diverse decomposer community.

• Bluhm, Hendrik; Diserens, Tom A.; Engleder, Thomas; Heising, Kaja; Heurich, Marco Dietmar & Janík, Tomáš [Show all 21 contributors for this article] (2023). Widespread habitat for Europe's largest herbivores, but poor connectivity limits recolonization. Diversity and Distributions: A Journal of Conservation Biogeography. ISSN 1366-9516. 29(3), p. 423–437. doi: 10.1111/ddi.13671. Full text in Research Archive Show summary

  Aim: Several large-mammal species in Europe have recovered and recolonized parts of their historical ranges. Knowing where suitable habitat exists, and thus where range expansions are possible, is important for proactively promoting coexistence between people and large mammals in shared landscapes. We aimed to assess the opportunities and limitations for range expansions of Europe's two largest herbivores, the European bison (Bison bonasus) and moose (Alces alces). Location: Central Europe. Methods: We used large occurrence datasets from multiple populations and species distribution models to map environmentally suitable habitats for European bison and moose across Central Europe, and to assess human pressure inside the potential habitat. We then used circuit theory modeling to identify potential recolonization corridors. Results: We found widespread suitable habitats for both European bison (>120,000 km2) and moose (>244,000 km2), suggesting substantial potential for range expansions. However, much habitat was associated with high human pressure (37% and 43% for European bison and moose, respectively), particularly in the west of Central Europe. We identified a strong east–west gradient of decreasing connectivity, with major barriers likely limiting natural recolonization in many areas. Main conclusions: We identify major potential for restoring large herbivores and their functional roles in Europe's landscapes. However, we also highlight considerable challenges for conservation planning and wildlife management, including areas where recolonization likely leads to human–wildlife conflict and where barriers to movement prevent natural range expansion. Conservation measures restoring broad-scale connectivity are needed in order to allow European bison and moose to recolonize their historical ranges. Finally, our analyses and maps indicate suitable but isolated habitat patches that are unlikely to be colonized but are candidate locations for reintroductions to establish reservoir populations. More generally, our work emphasizes that transboundary cooperation is needed for restoring large herbivores and their ecological roles, and to foster coexistence with people in Europe's landscapes.

• Mitterwallner, Veronika; Peters, Anne; Edelhoff, Hendrik; Mathes, Gregor; Nguyen, Hien & Peters, Wibke Erika Brigitta [Show all 8 contributors for this article] (2023). Automated visitor and wildlife monitoring with camera traps and machine learning. Remote Sensing in Ecology and Conservation. doi: 10.1002/rse2.367. Full text in Research Archive Show summary

  As human activities in natural areas increase, understanding human–wildlife interactions is crucial. Big data approaches, like large-scale camera trap studies, are becoming more relevant for studying these interactions. In addition, open-source object detection models are rapidly improving and have great potential to enhance the image processing of camera trap data from human and wildlife activities. In this study, we evaluate the performance of the open-source object detection model MegaDetector in cross-regional monitoring using camera traps. The performance at detecting and counting humans, animals and vehicles is evaluated by comparing the detection results with manual classifications of more than 300 000 camera trap images from three study regions. Moreover, we investigate structural patterns of misclassification and evaluate the results of the detection model for typical temporal analyses conducted in ecological research. Overall, the accuracy of the detection model was very high with 96.0% accuracy for animals, 93.8% for persons and 99.3% for vehicles. Results reveal systematic patterns in misclassifications that can be automatically identified and removed. In addition, we show that the detection model can be readily used to count people and animals on images with underestimating persons by −0.05, vehicles by −0.01 and animals by −0.01 counts per image. Most importantly, the temporal pattern in a long-term time series of manually classified human and wildlife activities was highly correlated with classification results of the detection model (Pearson's r = 0.996, p < 0.001) and diurnal kernel densities of activities were almost equivalent for manual and automated classification. The results thus prove the overall applicability of the detection model in the image classification process of cross-regional camera trap studies without further manual intervention. Besides the great acceleration in processing speed, the model is also suitable for long-term monitoring and allows reproducibility in scientific studies while complying with privacy regulations.

• Heidrich, Lea; Brandl, Roland; Ammer, Christian; Bae, Soyeon; Bässler, Claus & Doerfler, Inken [Show all 22 contributors for this article] (2023). Effects of heterogeneity on the ecological diversity and redundancy of forest fauna. Basic and Applied Ecology. ISSN 1439-1791. 73, p. 72–79. doi: 10.1016/j.baae.2023.10.005. Full text in Research Archive Show summary

  Heterogeneity in forests might promote biodiversity not only through an increase in niche volume but also through other processes, such as an increase in resources and their spatial distribution. However, negative relationships between heterogeneity and biodiversity have also been observed, which may indicate that heterogeneity acts as a filter for some species. This study examined the effects of different facets of heterogeneity in forest stands, i.e. deadwood, plant diversity, forest stand structure, and micro-scale topography, on the ecological (functional-phylogenetic) diversity and redundancy of nine animal groups: moths, true bugs, different functional groups of beetles, spiders, birds, and bats. Overall, we found positive effects of heterogeneity on ecological diversity and redundancy. Although the effect of heterogeneity at the local scale was moderate compared with the general effect of region, greater heterogeneity could be beneficial to some species groups and lead to more resilient species communities.

• Palmero, Stefano; Premier, Joe; Kramer-Schadt, Stephanie; Monterroso, Pedro & Heurich, Marco Dietmar (2023). Sampling variables and their thresholds for the precise estimation of wild felid population density with camera traps and spatial capture–recapture methods. Mammal Review. ISSN 0305-1838. 53(4), p. 223–237. doi: 10.1111/mam.12320. Full text in Research Archive Show summary

  1. Robust monitoring, providing information on population status, is fundamental for successful conservation planning. However, this can be hard to achieve for species that are elusive and occur at low densities, such as felids. These are often keystones of functioning ecosystems and are threatened by habitat loss and human persecution. 2. When elusive species can be individually identified by visible characteristics, for example via camera-trapping, observations of individuals can be used in combination with capture–recapture methods to calculate demographic parameters such as population density. In this context, spatial capture–recapture (SCR) outperforms conventional non-spatial methods, but the precision of results is inherently related to the sampling design, which should therefore be optimised. 3. We focussed on territorial felids in different habitats and investigated how the sampling designs implemented in the field affected the precision of population density estimates. We examined 137 studies that combined camera trapping and SCR methods for density estimation. From these, we collectedspatiotemporal parameters of their sampling designs, monitoring results, such as the number of individuals captured and the number of recaptures, as well as SCR detection parameters. We applied generalised linear mixed-effects models and tree-based regression methods to investigate the influence of variables on the precision of population density estimates and provide numerical thresholds. 4. Our analysis shows that the number of individuals, recapture frequency, and capture probability play the most crucial roles. Surveys yielding over 20 captured individuals that were recaptured on average at least once obtain the most precise population density estimates. 5. Based on our findings, we provide practical guidelines for future SCR studies that apply to all territorial felids. Furthermore, we present a standardised reporting protocol for study transparency and comparability. Our results will improve reporting and reproducibility of SCR studies and aid in setting up optimised sampling designs.

• Yu, Haili; Wang, Tiejun; Skidmore, Andrew; Heurich, Marco Dietmar & Bässler, Claus (2023). How future climate and tree distribution changes shape the biodiversity of macrofungi across Europe. Diversity and Distributions: A Journal of Conservation Biogeography. ISSN 1366-9516. 29(5), p. 666–682. doi: 10.1111/ddi.13688. Full text in Research Archive Show summary

  Aim: Climate change is affecting biodiversity at an accelerating rate. Despite the im-portance of fungi in ecosystems in general, and in the global carbon and nitrogen cycle in particular, there is little research on the response of fungi to climate change compared with plants and animals. Earlier studies show that climatic factors and tree species are key determinants of macrofungal diversity and distribution at large spatial scales. However, our knowledge of how climate change will affect macrofungal diver-sity and distribution in the future remains poorly understood.Location: Europe.Methods: Using openly available occurrence data of 1845 macrofungal species from eight European countries (i.e. Norway, Sweden, Finland, Denmark, Netherlands, Germany, France and Spain), we built ensemble species distribution models to predict macrofungal response to climate change alone and combined climate and tree distri-bution change under the IPCC special report on 2080 emissions scenarios (SRES A2 and B2).Results: Considering climate change alone, we predict that about 77% (74.1%–80.7%) of the modelled species will expand their distribution range, and around 57% (56.1%– 58.4%) of the modelled area will have an increase in macrofungal species richness. However, when considering the combined climate and tree species distribution change, only 50% (50%–50.9%) of the species are predicted to expand their distribu-tion range and 49% (47.4%–51.1%) of the modelled area will experience an increase in macrofungal species richness.Main Conclusions: Overall, our models projected that large areas would exhibit in-creased macrofungal species richness under future climate change. However, tree species distribution might play a restrictive role in the future distributional shifts of macrofungi. In addition, macrofungal responses appear heterogeneous, varying among species and regions. Our findings highlight the importance of including tree species in the projection of climate change impacts on the macrofungal diversity and distribution on a continental scale.

• Mumme, Steffen; Middleton, Arthur D.; Ciucci, Paolo; De Groeve, Johannes; Corradini, Andrea & Aikens, Ellen O. [Show all 32 contributors for this article] (2023). Wherever I may roam—Human activity alters movements of red deer (Cervus elaphus) and elk (Cervus canadensis) across two continents. Global Change Biology. ISSN 1354-1013. 29(20), p. 5788–5801. doi: 10.1111/gcb.16769. Full text in Research Archive Show summary

  Human activity and associated landscape modifications alter the movements of ani-mals with consequences for populations and ecosystems worldwide. Species perform-ing long-distance movements are thought to be particularly sensitive to human impact. Despite the increasing anthropogenic pressure, it remains challenging to understand and predict animals' responses to human activity. Here we address this knowledge gap using 1206 Global Positioning System movement trajectories of 815 individuals from 14 red deer (Cervus elaphus) and 14 elk (Cervus canadensis) populations spanning wide environmental gradients, namely the latitudinal range from the Alps to Scandinavia in Europe, and the Greater Yellowstone Ecosystem in North America. We measured individual-level movements relative to the environmental context, or movement ex-pression, using the standardized metric Intensity of Use, reflecting both the directional-ity and extent of movements. We expected movement expression to be affected by resource (Normalized Difference Vegetation Index, NDVI) predictability and topogra-phy, but those factors to be superseded by human impact. Red deer and elk movement expression varied along a continuum, from highly segmented trajectories over relatively small areas (high intensity of use), to directed transitions through restricted corridors (low intensity of use). Human activity (Human Footprint Index, HFI) was the strong-est driver of movement expression, with a steep increase in Intensity of Use as HFI increased, but only until a threshold was reached. After exceeding this level of impact, the Intensity of Use remained unchanged. These results indicate the overall sensitivity of Cervus movement expression to human activity and suggest a limitation of plastic responses under high human pressure, despite the species also occurring in human-dominated landscapes. Our work represents the first comparison of metric- based movement expression across widely distributed populations of a deer genus, contribut-ing to the understanding and prediction of animals' responses to human activity.

• Tucker, Marlee A.; Schipper, Aafke M.; Adams, Tempe S.F.; Attias, Nina; Avgar, Tal & Babic, Natarscha L. [Show all 82 contributors for this article] (2023). Behavioral responses of terrestrial mammals to COVID-19 lockdowns. Science. ISSN 0036-8075. 380(6649), p. 1059–1064. doi: 10.1126/science.abo6499. Full text in Research Archive Show summary

  COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals' 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.

• Wielgus, Elodie; Mandinyenya, Bob; Wieprecht, Sashimi & Heurich, Marco Dietmar (2023). Bringing the Black rhino back: Key factors for reintroduction success. Global Ecology and Conservation. 48. doi: 10.1016/j.gecco.2023.e02756. Full text in Research Archive Show summary

  Evaluating reintroduction success is fundamental to wildlife management and conservation. Movement affects animal fitness and survival and is the first response of reintroduced animals, making it an excellent indicator of reintroduction success. However, there is limited information on the early post-release movement of reintroduced animals. Here, we addressed this important issue by studying the post-release behaviour of the critically endangered black rhinoceros, Diceros bicornis minor, reintroduced to the Gonarezhou National Park, Zimbabwe, in 2021. We used daytime sighting data collected from 21 rhinoceros for 1.5 years to investigate survival and reproduction, movement patterns and habitat selection after release. We examine how sex, age and different release sites affect the short-term movement behaviour and habitat selection of black rhinos. Rhinos showed progressive and consistent changes in movement patterns and habitat selection, shifting from large-scale movements during the early stages of release to smaller-scale movements after home ranges were established. We found that rhinos released in the large area had larger activity areas with less overlap between individuals and moved further away from the release site (less fidelity to the release site) than the individuals released in the smaller area. These findings confirm the great capacity of black rhinos to adapt to the environment, occupying large ranges when given the opportunity, but populations with smaller ranges can also be viable. Based on our study and a literature review, we stress the importance of long-term monitoring and believe that reserve size, rhino density, fencing, food and water availability, familiarity between conspecifics and human disturbance are key factors in the successful establishment of a rhino population that should be considered in future reintroductions. Finally, the high survival and birth rates in the first 1.5 years after reintroduction, together with most rhinos having established their home range, suggest a successful reintroduction in the short term.

• Groeve, Johannes De; Weghe, Nico Van de; Ranc, Nathan; Morellet, Nicolas; Bonnot, Nadège C. & Gehr, Benedikt [Show all 13 contributors for this article] (2023). Back and forth: day–night alternation between cover types reveals complementary use of habitats in a large herbivore. Landscape Ecology. ISSN 0921-2973. 38, p. 1033–1049. doi: 10.1007/s10980-023-01594-1. Full text in Research Archive Show summary

  Context The Complementary Habitat Hypothesis posits that animals access resources for diferent needs by moving between complementary habitats that can be seen as ‘resource composites’. These movements can occur over a range of temporal scales, from diurnal to seasonal, in response to multiple drivers such as access to food, weather constraints, risk avoidance and human disturbance. Within this framework, we hypothesised that large herbivores cope with human-altered landscapes through the alternate use of complementary habitats at both daily and seasonal scales. Objectives We tested the Complementary Habitat Hypothesis in European roe deer (Capreolus capreolus) by classifying 3900 habitat-annotated movement trajectories of 154 GPS-monitored individuals across contrasting landscapes. Methods We considered day-night alternation between open food-rich and closed refuge habitats as a measure of complementary habitat use. We frst identifed day–night alternation using the Individual Movement - Sequence Analysis Method, then we modelled the proportion of day–night alternation over the year in relation to population and individual characteristics. Results We found that day-night alternation is a widespread behaviour in roe deer, even across markedly diferent landscapes. Day–night alternation followed seasonal trends in all populations, partly linked to vegetation phenology. Within populations, seasonal patterns of open/closed habitat alternation difered between male and female adults, but not in juveniles. Conclusion Our results support the Complementary Habitat Hypothesis by showing that roe deer adjust their access to the varied resources available in complex landscapes by including diferent habitats within their home range, and sequentially alternating between them in response to seasonal changes and individual life history. Animal trajectories · Habitat use · IM-SAM · Resource composites · Roe deer · Sequential analysis methods · Spatio-temporal patterns · Vegetation green up

• Oeser, Julian; Heurich, Marco Dietmar; Kramer‑Schadt, Stephanie; Andrén, Henrik; Bagrade, Guna & Belotti, Elisa [Show all 37 contributors for this article] (2023). Prerequisites for coexistence: human pressure and refuge habitat availability shape continental‑scale habitat use patterns of a large carnivore. Landscape Ecology. ISSN 0921-2973. 38, p. 1713–1728. doi: 10.1007/s10980-023-01645-7. Full text in Research Archive Show summary

  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. Animal tracking · Adjustment · Eurasian lynx · Functional response · Habitat availability · Lynx lynx

• Dersch, S.; Schöttl, A.; Krzystek, P. & Heurich, Marco Dietmar (2023). Towards complete tree crown delineation by instance segmentation with Mask R–CNN and DETR using UAV-based multispectral imagery and lidar data. ISPRS Open Journal of Photogrammetry and Remote Sensing (IOJPRS). 8. doi: 10.1016/j.ophoto.2023.100037. Full text in Research Archive Show summary

  Precise single tree delineation allows for a more reliable determination of essential parameters such as tree species, height and vitality. Methods of instance segmentation are powerful neural networks for detecting and segmenting single objects and have the potential to push the accuracy of tree segmentation methods to a new level. In this study, two instance segmentation methods, Mask R–CNN and DETR, were applied to precisely delineate single tree crowns using multispectral images and images generated from UAV lidar data. The study area was in Bavaria, 35 km north of Munich (Germany), comprising a mixed forest stand of around 7 ha characterised mainly by Norway spruce (Picea abies) and large groups of European beeches (Fagus sylvatica) with 181–236 trees per ha. The data set, consisting of multispectral images and lidar data, was acquired using a Micasense RedEdge-MX dual camera system and a Riegl miniVUX-1UAV lidar scanner, both mounted on a hexacopter (DJI Matrice 600 Pro). At an altitude of approximately 85 m, two flight missions were conducted at an airspeed of 5 m/s, leading to a ground resolution of 5 cm and a lidar point density of 560 points/m2. In total, 1408 trees were marked by visual interpretation of the remote sensing data for training and validating the classifiers. Additionally, 125 trees were surveyed by tacheometric means used to test the optimized neural networks. The evaluations showed that segmentation using only multispectral imagery performed slightly better than with images generated from lidar data. In terms of F1 score, Mask R–CNN with color infrared (CIR) images achieved 92% in coniferous, 85% in deciduous and 83% in mixed stands. Compared to the images generated by lidar data, these scores are the same for coniferous and slightly worse for deciduous and mixed plots, by 4% and 2%, respectively. DETR with CIR images achieved 90% in coniferous, 81% in deciduous and 84% in mixed stands. These scores were 2%, 1%, and 2% worse, respectively, compared to the lidar data images in the same test areas. Interestingly, four conventional segmentation methods performed significantly worse than CIR-based and lidar-based instance segmentations. Additionally, the results revealed that tree crowns were more accurately segmented by instance segmentation. All in all, the results highlight the practical potential of the two deep learning-based tree segmentation methods, especially in comparison to baseline methods.

• Kudrenko, Svitlana; Fenchuk, Viktar; Vollering, Julien Martin Marie; Zedrosser, Andreas; Selva, Nuria & Ostapowicz, Katarzyna Anna [Show all 8 contributors for this article] (2023). Walking on the dark side: Anthropogenic factors limit suitable habitat for gray wolf (Canis lupus) in a large natural area covering Belarus and Ukraine. Global Ecology and Conservation. 46. doi: 10.1016/j.gecco.2023.e02586. Full text in Research Archive Show summary

  Due to successful conservation initiatives and legislations, the grey wolf (Canis lupus) is re-colonising its historic range in Europe. However, wolves have never been extirpated across large areas in Eastern Europe but are often constrained to remote and inaccessible places due to centuries of persecution. This study aimed to identify the potentially suitable wolf habitats in Polesia, a massive cross-border lowland region extending over southern Belarus and northern Ukraine, which are often neglected in large carnivore studies at the continental scale. We hypothesized that anthropogenic rather than environmental factors govern wolf habitat suitability. We used a dataset of 4191 GPS locations obtained from radio-collared wolves (n = 26) and confirmed observations (n = 231) during 2014–2021 and applied maximum entropy method to estimate relative habitat suitability for wolves in Polesia. Artificial light at night (ALAN), proportion of cropland and tree cover were the most important factors affecting wolf habitat suitability. Road densities contributed poorly to predicting habitat suitability for wolves. Our models predicted a quarter of Polesia as suitable habitat and revealed priority areas connecting the important source populations in the Chornobyl Exclusion Zone in the east and the Białowieża Forest in the west and thus essential for long-term wolf conservation. Our results provide the bases for effective, long-term wolf monitoring and management programs in both Belarus and Ukraine. However, national and transboundary wolf management in Polesia has been extremely challenging since 2022 due to the ongoing war and subsequent habitat degradation in this part of Europe.

• Khorozyan, Igor & Heurich, Marco Dietmar (2023). Patterns of predation by the Eurasian lynx Lynx lynx throughout its range: ecological and conservation implications. Mammal Review. ISSN 0305-1838. 53(3), p. 177–188. doi: 10.1111/mam.12317. Full text in Research Archive
• Tourani, Mahdieh; Franke, Frederik; Heurich, Marco Dietmar; Henrich, Maik; Peterka, Tomáš & Ebert, Cornelia [Show all 12 contributors for this article] (2023). Spatial variation in red deer density in a transboundary forest ecosystem. Scientific Reports. 13(1). doi: 10.1038/s41598-023-31283-7. Full text in Research Archive Show summary

  Forests in Europe are exposed to increasingly frequent and severe disturbances. The resulting changes in the structure and composition of forests can have profound consequences for the wildlife inhabiting them. Moreover, wildlife populations in Europe are often subjected to differential management regimes as they regularly extend across multiple national and administrative borders. The red deer Cervus elaphus population in the Bohemian Forest Ecosystem, straddling the Czech-German border, has experienced forest disturbances, primarily caused by windfalls and bark beetle Ips typographus outbreaks during the past decades. To adapt local management strategies to the changing environmental conditions and to coordinate them across the international border, reliable estimates of red deer density and abundance are highly sought-after by policymakers, wildlife managers, and stakeholders. Covering a 1081-km2 study area, we conducted a transnational non-invasive DNA sampling study in 2018 that yielded 1578 genotyped DNA samples from 1120 individual red deer. Using spatial capture-recapture models, we estimated total and jurisdiction-specific abundance of red deer throughout the ecosystem and quantified the role of forest disturbance and differential management strategies in shaping spatial heterogeneity in red deer density. We hypothesised that (a) forest disturbances provide favourable habitat conditions (e.g., forage and cover), and (b) contrasting red deer management regimes in different jurisdictions create a differential risk landscape, ultimately shaping density distributions. Overall, we estimated that 2851 red deer (95% Credible Interval = 2609–3119) resided in the study area during the sampling period, with a relatively even overall sex ratio (1406 females, 95% CI = 1229–1612 and 1445 males, 95% CI = 1288–1626). The average red deer density was higher in Czechia (3.5 km−2, 95% CI = 1.2–12.3) compared to Germany (2 km−2, 95% CI = 0.2–11). The effect of forest disturbances on red deer density was context-dependent. Forest disturbances had a positive effect on red deer density at higher elevations and a negative effect at lower elevations, which could be explained by partial migration and its drivers in this population. Density of red deer was generally higher in management units where hunting is prohibited. In addition, we found that sex ratios differed between administrative units and were more balanced in the non-intervention zones. Our results show that the effect of forest disturbances on wild ungulates is modulated by additional factors, such as elevation and ungulate management practices. Overall density patterns and sex ratios suggested strong gradients in density between administrative units. With climate change increasing the severity and frequency of forest disturbances, population-level monitoring and management are becoming increasingly important, especially for wide-ranging species as both wildlife and global change transcend administrative boundaries.

• Palmero, Stefano; Smith, Adam F.; Kudrenko, Svitlana; Gahbauer, Martin; Dachs, Dominik & Weingarth-Dachs, Kirsten [Show all 15 contributors for this article] (2023). Shining a light on elusive lynx: Density estimation of three Eurasian lynx populations in Ukraine and Belarus. Ecology and Evolution. 13(11). doi: 10.1002/ece3.10688. Full text in Research Archive Show summary

  The Eurasian lynx is a large carnivore widely distributed across Eurasia. However, our understanding of population status is heterogeneous across their range, with some populations isolated that are at risk of reduced genetic variation and a complete lack of information about others. In many European countries, Eurasian lynx are monitored through demographic studies crucial for their conservation and management. Even so, there are only rough and fragmented population assessments from Ukraine and Belarus, despite strict protection in both countries and their importance for lynx connectivity across Europe. We monitored lynx from October 2020 to March 2021 and used camera trapping in combination with spatial capture–recapture (SCR) methods in a Bayesian framework to provide the first SCR density estimation of three lynx populations across Ukraine and Belarus, including the Ukrainian Chornobyl Exclusion Zone, southern Belarus and the Ukrainian Carpathians. Our density estimates varied within our study areas ranging from 0.45 to 1.54 individuals/100 km2. This work provides a substantial scientific component to the overall understanding of lynx conservation for a region where only broad information is available and opens the doors for further large-scale monitoring and trend assessments. The crucial information we provide can greatly enhance the range-wide assessments of the status of this protected species. We also discuss the implications for Eurasian lynx conservation, despite the geopolitical realities impacting species monitoring in the region. Our work serves as a baseline, not only for future conservation interventions but also to evaluate the effects of disturbance and threats to these protected populations.

• König, Simon; Thonfeld, Frank; Förster, Michael; Dubovyk, Olena & Heurich, Marco Dietmar (2023). Assessing Combinations of Landsat, Sentinel-2 and Sentinel-1 Time series for Detecting Bark Beetle Infestations. GIScience & Remote Sensing. ISSN 1548-1603. 60(1). doi: 10.1080/15481603.2023.2226515. Full text in Research Archive Show summary

  Bark beetle infestations are among the most substantial forest disturbance agents worldwide. Moreover, as a consequence of global climate change, they have increased in frequency and in the size and number of affected areas. Controlling bark beetle outbreaks requires consistent operational monitoring, as is possible using satellite data. However, while many satellite-based approaches have been developed, the full potential of dense, multi-sensor time series has yet to be fully explored. Here, for the first time, we used all available multispectral data from Landsat and Sentinel-2, Sentinel-1 SAR data, and combinations thereof to detect bark beetle infestations in the Bavarian Forest National Park. Based on a multi-year reference dataset of annual infested areas, we assessed the separability between healthy and infested forests for various vegetation indices calculated from the satellite data. We used two approaches to compute infestation probability time series from the different datasets: Bayesian conditional probabilities, based on the best-separating index from each satellite type, and random forest regression, based on all indices from each satellite type. Five different sensor configurations were tested for their detection capabilities: Landsat alone, Sentinel-1 alone, Sentinel-2 alone, Landsat and Sentinel-2 combined, and data from all satellite types combined. The best overall results in terms of spatial accuracy were achieved with Sentinel-2 (max. overall accuracy: 0.93). The detections of Sentinel-2 also were the closest to the onset of infestation estimated for each year. Sentinel-2 detected infested areas in larger contiguous patches with higher reliability compared to smaller patches. The results achieved with Landsat were somewhat inferior to those of Sentinel-2 (max. accuracy: 0.89). While yielding similar results, the combination of Landsat and Sentinel-2 did not provide any advantages over using Landsat or Sentinel-2 alone (max. accuracy: 0.87), while Sentinel-1 was unable to detect infested areas (max. accuracy: 0.62). The combined data of all three satellite types did not achieve satisfactory results either (max. accuracy: 0.67). Spatial accuracies were typically higher for Bayesian conditional probabilities than for random forest-derived probabilities, but the latter resulted in earlier detections. The approach presented herein provides a flexible disturbance detection pipeline well-suited for the monitoring of bark beetle outbreaks. Furthermore, it can also be applied to other disturbance types.

• Rietz, Janine; Calkoen, Suzanne T. S van Beeck; Ferry, Nicolas; Schlüter, Jens; Wehner, Helena & Schindlatz, Karl-Heinz [Show all 11 contributors for this article] (2023). Drone-Based Thermal Imaging in the Detection of Wildlife Carcasses and Disease Management. Transboundary and Emerging Diseases. ISSN 1865-1674. 2023. doi: 10.1155/2023/5517000. Full text in Research Archive Show summary

  Because animal carcasses often serve as reservoirs for pathogens, their location and removal are crucial in controlling the spread of diseases. During carcass decomposition, heat is emitted due to microbial activity and the development of maggots. Recent studies have shown that infrared sensors can be used to locate animal carcasses, but little is known about the factors influencing detection success. In this study, we investigated the potential of infrared technology to locate wild boar carcasses, as they play an important role in the spread of African swine fever. Specifically, we tested the effects of environmental and carcass conditions on the detection probability. A drone-based thermal camera was used to collect data during 379 flyovers of 42 wild boar carcasses in different stages of decomposition between September 2020 and July 2021. Generalized mixed-effect models and conditional inference trees were used to identify the environmental and carcass conditions that influenced the detection probability. Our results showed that the thermal camera accurately measured carcass temperature (R2 = 0.75, RMSE = 5.89°C). The probability of finding carcasses was higher in open habitats with air temperatures >3.0°C and thus conducive to maggot development (detection rate ≤80%). A forest canopy openness >29.3% and cloudy conditions or flights at dawn increased the detection rate. Moreover, carcasses infested with large amounts of maggots could be detected even in habitats with a more extensive canopy cover, whereas in dense forests, the detection probability was limited (<25%). Carcasses in an advanced stage of decomposition could still be detected as long as the difference between the carcass temperature and the air temperature was >6.4°C (≤62%). Our study demonstrates the utility of thermal imaging in searching for wild boar carcasses under specific environmental and carcass conditions and thus its use in supporting ground searches.

• Ruiz-Villar, Héctor; Bastianelli, Matteo Luca; Heurich, Marco Dietmar; Anile, Stefano; Díaz-Ruiz, Francisco & Ferreras, Pablo [Show all 18 contributors for this article] (2023). Agriculture intensity and landscape configuration influence the spatial use of wildcats across Europe. Biological Conservation. ISSN 0006-3207. 277. doi: 10.1016/j.biocon.2022.109854. Full text in Research Archive
• Oeser, Julian; Heurich, Marco Dietmar; Kramer-Schadt, Stephanie A.; Mattisson, Jenny; Krofel, Miha & Krojerová-Prokešová, Jarmila [Show all 40 contributors for this article] (2023). Integrating animal tracking datasets at a continental scale for mapping Eurasian lynx habitat. Diversity and Distributions: A Journal of Conservation Biogeography. ISSN 1366-9516. 29(12), p. 1546–1560. doi: 10.1111/ddi.13784. Full text in Research Archive Show summary

  Aim: The increasing availability of animal tracking datasets collected across many sites provides new opportunities to move beyond local assessments to enable detailed and consistent habitat mapping at biogeographical scales. However, integrating wildlife datasets across large areas and study sites is challenging, as species' varying responses to different environmental contexts must be reconciled. Here, we compare approaches for large-area habitat mapping and assess available habitat for a recolonizing large carnivore, the Eurasian lynx (Lynx lynx). Location: Europe. Methods: We use a continental-scale animal tracking database (450 individuals from 14 study sites) to systematically assess modelling approaches, comparing (1) global strategies that pool all data for training versus building local, site-specific models and combining them, (2) different approaches for incorporating regional variation in habitat selection and (3) different modelling algorithms, testing nonlinear mixed effects models as well as machine-learning algorithms. Results: Testing models on training sites and simulating model transfers, global and local modelling strategies achieved overall similar predictive performance. Model performance was the highest using flexible machine-learning algorithms and when incorporating variation in habitat selection as a function of environmental variation. Our best-performing model used a weighted combination of local, site-specific habitat models. Our habitat maps identified large areas of suitable, but currently unoccupied lynx habitat, with many of the most suitable unoccupied areas located in regions that could foster connectivity between currently isolated populations. Main Conclusions: We demonstrate that global and local modelling strategies can achieve robust habitat models at the continental scale and that considering regional variation in habitat selection improves broad-scale habitat mapping. More generally, we highlight the promise of large wildlife tracking databases for large-area habitat mapping. Our maps provide the first high-resolution, yet continental assessment of lynx habitat across Europe, providing a consistent basis for conservation planning for restoring the species within its former range. animal tracking, Eurasian lynx, habitat suitability, large carnivore, large-area mapping, Lynx lynx

• Döringer, Stefanie; Porst, Florian; Stumpf, Lena & Heurich, Marco Dietmar (2023). The Relationship between Measured Visitor Density and Perceived Crowding Revisited: Predicting Perceived Crowding in Outdoor Recreation. Leisure Sciences. ISSN 0149-0400. doi: 10.1080/01490400.2023.2265366. Full text in Research Archive
• Bubnicki, Jakub W.; Norton, Ben; Baskauf, Steven J.; Bruce, Tom; Cagnacci, Francesca & Casaer, Jim [Show all 36 contributors for this article] (2023). Camtrap DP: an open standard for the FAIR exchange and archiving of camera trap data. Remote Sensing in Ecology and Conservation. 10(3), p. 283–295. doi: 10.1002/rse2.374. Full text in Research Archive Show summary

  Camera trapping has revolutionized wildlife ecology and conservation by providing automated data acquisition, leading to the accumulation of massive amounts of camera trap data worldwide. Although management and processing of camera trap-derived Big Data are becoming increasingly solvable with the help of scalable cyber-infrastructures, harmonization and exchange of the data remain limited, hindering its full potential. There is currently no widely accepted standard for exchanging camera trap data. The only existing proposal, “Camera Trap Metadata Standard” (CTMS), has several technical shortcomings and limited adoption. We present a new data exchange format, the Camera Trap Data Package (Camtrap DP), designed to allow users to easily exchange, harmonize and archive camera trap data at local to global scales. Camtrap DP structures camera trap data in a simple yet flexible data model consisting of three tables (Deployments, Media and Observations) that supports a wide range of camera deployment designs, classification techniques (e.g., human and AI, media-based and event-based) and analytical use cases, from compiling species occurrence data through distribution, occupancy and activity modeling to density estimation. The format further achieves interoperability by building upon existing standards, Frictionless Data Package in particular, which is supported by a suite of open software tools to read and validate data. Camtrap DP is the consensus of a long, in-depth, consultation and outreach process with standard and software developers, the main existing camera trap data management platforms, major players in the field of camera trapping and the Global Biodiversity Information Facility (GBIF). Under the umbrella of the Biodiversity Information Standards (TDWG), Camtrap DP has been developed openly, collaboratively and with version control from the start. We encourage camera trapping users and developers to join the discussion and contribute to the further development and adoption of this standard. Biodiversity data, camera traps, data exchange, data sharing, information standards

• Nussberger, Beatrice; Barbosa, Soraia; Beaumont, Mark; Currat, Mathias; Devillard, Sébastien & Heurich, Marco Dietmar [Show all 12 contributors for this article] (2023). A common statement on anthropogenic hybridization of the European wildcat (Felis silvestris). Frontiers in Ecology and Evolution. 11. doi: 10.3389/fevo.2023.1156387. Full text in Research Archive Show summary

  Preserving natural genetic diversity and ecological function of wild species is a central goal in conservation biology. As such, anthropogenic hybridization is considered a threat to wild populations, as it can lead to changes in the genetic makeup of wild species and even to the extinction of wild genomes. In European wildcats, the genetic and ecological impacts of gene flow from domestic cats are mostly unknown at the species scale. However, in small and isolated populations, it is known to include genetic swamping of wild genomes. In this context, it is crucial to better understand the dynamics of hybridization across the species range, to inform and implement management measures that maintain the genetic diversity and integrity of the European wildcat. In the present paper, we aim to provide an overview of the current scientific understanding of anthropogenic hybridization in European wildcats, to clarify important aspects regarding the evaluation of hybridization given the available methodologies, and to propose guidelines for management and research priorities.

• Khorozyan, Igor & Heurich, Marco Dietmar (2023). Where, why and how carnivores kill domestic animals in different parts of their ranges: An example of the Eurasian lynx. Global Ecology and Conservation. 46. doi: 10.1016/j.gecco.2023.e02585. Full text in Research Archive Show summary

  Human-carnivore conflicts over predation on domestic animals are a global challenge. Knowledge of determinants and patterns of predation on domestic animals is an essential prerequisite to develop and apply effective interventions against carnivores. Yet, it is surprisingly little known about how these determinants and patterns vary across different parts of the distribution areas of individual carnivore species. We synthesized published information on Eurasian lynx (Lynx lynx) predation in terms of: (a) domestic prey species, (b) selectivity, kill rates and consumption; (c) problem seasons; (d) problem individuals and sex/age categories of lynx; (e) problem areas (hotspots); (f) predation in Europe and Asia; and (g) effects of livestock protection interventions. Using a global database of dietary profiles (104 cases from 39 publications), we found that the main domestic animals killed and consumed by lynx are semi-domestic reindeer (Rangifer tarandus) and sheep (Ovis aries). Predation patterns on these two species are very different. Reindeer tend to be predated as a main wild prey species, whereas sheep are primarily available during summer and appear to be killed upon chance encounters (mainly lambs), mostly by male lynx, in predictable hotspot areas. As sheep and especially reindeer graze over remote areas without human attendance, only few interventions can be effectively used, with a primary focus on hotspot areas and peak seasons associated with the highest losses to lynx. Electric fencing and herding have been recommended as practical tools for sheep protection on small to medium scales, whereas compensation of confirmed losses is mostly ineffective as poaching still remains to be the major cause of lynx mortality. Risk-based compensations and performance payments are promising, but their application in lynx has yet to be tested.

• Henrich, Maik; Burgueño, Mercedes; Hoyer, Jacqueline; Haucke, Timm; Steinhage, Volker & Kühl, Hjalmar S. [Show all 7 contributors for this article] (2023). A semi-automated camera trap distance sampling approach for population density estimation. Remote Sensing in Ecology and Conservation. doi: 10.1002/rse2.362. Full text in Research Archive Show summary

  Camera traps have become important tools for the monitoring of animal populations. However, the study-specific estimation of animal detection probabilities is key if unbiased abundance estimates of unmarked species are to be obtained. Since this process can be very time-consuming, we developed the first semi-automated workflow for animals of any size and shape to estimate detection probabilities and population densities. In order to obtain observation distances, a deep learning algorithm is used to create relative depth images that are calibrated with a small set of reference photos for each location, with distances then extracted for animals automatically detected by MegaDetector 4.0. Animal detection by MegaDetector was generally independent of the distance to the camera trap for 10 animal species at two different study sites. If an animal was detected both manually and automatically, the difference in the distance estimates was often minimal at a distance about 4 m from the camera trap. The difference increased approximately linearly for larger distances. Nonetheless, population density estimates based on manual and semi-automated camera trap distance sampling workflows did not differ significantly. Our results show that a readily available software for semi-automated distance estimation can reliably be used within a camera trap distance sampling workflow, reducing the time required for data processing, by >13-fold. This greatly improves the accessibility of camera trap distance sampling for wildlife research and management.

• Peters, Anne; Ruess, Ramona & Heurich, Marco Dietmar (2023). Welche Auswirkungen haben Erholungs-aktivitäten auf Verhalten, Physiologie und Demografie von Wildtieren? Ergebnisse einer vergleichenden Literaturstudie. Naturschutz und Landschaftsplanung. ISSN 0940-6808. 55(1). doi: 10.1399/NuL.2023.01.02. Full text in Research Archive Show summary

  Freizeitaktivitäten wie Wandern und Radfahren erfreuen sich wachsender Beliebtheit, was sich in steigenden Besucherzahlen vor allem in Schutzgebieten widerspiegelt. Diese Literaturstudie zeigt, dass Erholungsaktivitäten nachteilige Effekte auf Verhalten, Physiologie und Demografie von Wildtieren haben. Große Raubtiere, Mesoprädatoren und Huftiere reagieren unter anderem mit erhöhter Wachsamkeit und Fluchtverhalten auf Erholungsnutzung. Zudem werden Ruhezeiten der Tiere reduziert, ihre Nahrungssuche gestört und ihr Stressniveau erhöht. Langfristig kann Erholungsnutzung zu einer Verschiebung der zeitlichen und räumlichen Aktivität von Wildtieren sowie einer Verminderung ihres Fortpflanzungserfolges führen. Aufgrund von Wechselwirkungen verschiedener Umweltvariablen und individueller Faktoren können die Reaktionen der Wildtiere unterschiedlich stark ausfallen. Um Auswirkungen von Erholungsnutzung auf Wildtiere zu vermindern, sollte im Rahmen von Managementmaßnahmen die räumliche und zeitliche Trennung von Erholungssuchenden und Wildtieren durch Regelungen, wie etwa ein Wegegebot und räumliche und/oder zeitliche Betretungsverbote, sowie durch gezielte Lenkung von Besucherströmen und gegebenenfalls eine Reduzierung des bestehenden Wegenetzes gefördert werden. Eine Sensibilisierung der Besucher hinsichtlich der Effekte ihrer Aktivitäten auf Wildtiere kann ebenfalls dazu beitragen, die Einhaltung von Regeln zu fördern und somit negative Auswirkungen zu verringern.

• Gatiso, Tsegaye T.; Kulik, Lars; Bachmann, Mona; Bonn, Aletta; Bösch, Lukas & Eirdosh, Dustin [Show all 13 contributors for this article] (2022). Effectiveness of protected areas influenced by socio-economic context. Nature Sustainability. 5, p. 861–868. doi: 10.1038/s41893-022-00932-6. Full text in Research Archive Show summary

  Protected area (PA) performance is thought to depend on effective conservation management and favourable socio-economic context. However, increasing evidence of continued biodiversity decline within PAs raises the question of whether fundamental ecological and socio-economic constraints might actually affect PA effectiveness. Here we quantify how threats to biodiversity, socio-economic context and conservation efforts play out across 114 PAs in 25 European and African countries. We found that even in the presence of highly favourable socio-economic context and conservation efforts, it is not possible to completely offset the intensity of threats and prevent biodiversity decline. Projections show that halting biodiversity decline across the studied PA network may require at least a 35% increase in conservation efforts over a decade. However, as PAs approach zero biodiversity loss, even greater efforts and resources would be needed because of the principle of diminishing marginal returns. Our findings point to limited effectiveness of PAs and their management that might not be possible to address by simply increasing resources. Additionally, the adoption of core design principles of sustainable systems that take into account the social–ecological contexts of PAs could help overcome the observed hurdles of limited effectiveness and thus better integrate PAs into sustainable development efforts.

• Calkoen, Suzanne T. S. van Beeck; Deis, Michele H.; Oeser, Julian; Kuijper, Dries P. J. & Heurich, Marco Dietmar (2022). Humans rather than Eurasian lynx (Lynx lynx) shape ungulate browsing patterns in a temperate forest. Ecosphere. 13(2). doi: 10.1002/ecs2.3931. Full text in Research Archive Show summary

  The recolonization of human-dominated landscapes by large carnivores has been followed with considerable scientific interest; however, little is known about their interactive effect on ungulate foraging behavior. This study compared the risks imposed by humans and lynx on ungulate foraging behavior by examining the effects of browsing intensity (at two spatial scales), diet quality, and tree species selection. We hypothesized that: (1) in areas with high risk imposed by humans and lynx browsing intensity would be reduced; (2) risk effects would interact with habitat visibility at a fine scale, resulting in contrasting browsing patterns in response to humans versus lynx risk; (3) ungulates compensate for the higher costs incurred in high-risk areas by switching to a higher diet quality, and (4) browse a higher proportion of more-preferred tree species. These hypotheses were tested by measuring browsing intensity along 48 transects located at different distances from human settlements within the hunted and nonhunted areas of the Bavarian Forest. Dung samples were collected and analyzed as a proxy of diet quality (C:N ratio, fiber). The spatial patterns of browsing intensity, diet quality, and tree species selection were then linked to lynx risk, hunting intensity, recreation intensity, and distance to human settlements. Our results showed that (1) browsing intensity strongly decreased with increasing recreational activities, whereas it increased with lynx risk; (2) only in close proximity to human settlements tree browsing was higher in dense habitats and (3) a higher diet quality was obtained. (4) We found a stronger avoidance of the less preferred tree species in high-hunting intensity areas. In conclusion, our results indicate that the risk effects of human activities outweigh those of a natural large carnivore. Thus, highlighting the importance of taking those activities into account in predicting the impacts of large carnivores on ungulates and their plant-food choices.

• Yu, Haili; Wang, Tiejun; Skidmore, Andrew; Heurich, Marco Dietmar & Bässler, Claus (2022). 50 Years of Cumulative Open-Source Data Confirm Stable and Robust Biodiversity Distribution Patterns for Macrofungi. Journal of fungi (JoF). 8(9). doi: 10.3390/jof8090981. Full text in Research Archive Show summary

  Fungi are a hyper-diverse kingdom that contributes significantly to the regulation of the global carbon and nutrient cycle. However, our understanding of the distribution of fungal diversity is often hindered by a lack of data, especially on a large spatial scale. Open biodiversity data may provide a solution, but concerns about the potential spatial and temporal bias in species occurrence data arising from different observers and sampling protocols challenge their utility. The theory of species accumulation curves predicts that the cumulative number of species reaches an asymptote when the sampling effort is sufficiently large. Thus, we hypothesize that open biodiversity data could be used to reveal large-scale macrofungal diversity patterns if these datasets are accumulated long enough. Here, we tested our hypothesis with 50 years of macrofungal occurrence records in Norway and Sweden that were downloaded from the Global Biodiversity Information Facility (GBIF). We first grouped the data into five temporal subsamples with different cumulative sampling efforts (i.e., accumulation of data for 10, 20, 30, 40 and 50 years). We then predicted the macrofungal diversity and distribution at each subsample using the maximum entropy (MaxEnt) species distribution model. The results revealed that the cumulative number of macrofungal species stabilized into distinct distribution patterns with localized hotspots of predicted macrofungal diversity with sampling efforts greater than approximately 30 years. Our research demonstrates the utility and importance of the long-term accumulated open biodiversity data in studying macrofungal diversity and distribution at the national level.

• Filla, Marc; Lama, Rinzin Phunjok; Ghale, Tashi Rapte; Filla, Tim; Heurich, Marco Dietmar & Waltert, Matthias [Show all 7 contributors for this article] (2022). Blue sheep strongly affect snow leopard relative abundance but not livestock depredation in the Annapurna Conservation Area, Nepal. Global Ecology and Conservation. 37. doi: 10.1016/j.gecco.2022.e02153. Full text in Research Archive Show summary

  Large carnivores play key roles in their ecosystems, but their protection is a major challenge in biodiversity conservation due to conflicts with human interests. The snow leopard (Panthera uncia) is the top predator of Asian high-altitude landscapes and faces various threats including wild prey depletion and illegal killings as a consequence of livestock depredation. As the interactions between snow leopards, wild prey, and livestock are still insufficiently understood, we studied the effects of 1) wild prey (blue sheep Pseudois nayaur and Himalayan marmots Marmota himalayana) and domestic prey on snow leopard relative abundance, and of 2) these ecological parameters and intervention applications on livestock depredation by snow leopards. In the Annapurna Conservation Area, Nepal, we monitored wildlife populations and livestock along transects (490.8 km) in 82 grid cells (4 ×4 km) in 2019 and 2021 and conducted questionnaire surveys to determine livestock depredation between 2018 and 2021 (n = 479 households). We applied generalized linear models (GLMs) and sample comparison testing to examine the effects of prey densities and other environmental and anthropogenic predictors on snow leopard relative abundance and livestock depredation. Blue sheep density strongly positively affected snow leopard relative abundance, which also increased with terrain ruggedness and decreased with increasing densities of livestock and the human population. The size of livestock holdings shaped depredation events of large livestock (yak, cattle and horse), whereas depredation events of sheep and goats, which accounted for most (68.6%) depredated animals, decreased with increasing human population density and marmot presence. The strong impact of blue sheep on snow leopard relative abundance supports demands for integrating this ungulate into conservation and management plans, including wild prey recovery and translocation. The rather weak evidence for effects of blue sheep on depredation events suggests that conflicts over livestock depredation by snow leopards would neither be inflicted nor solved by increasing wild prey abundance. This demonstrates the need to improve intervention strategies in the Annapurna region, such as predator-proofing corrals and optimizing daytime herding practices. We suggest further exploring the effects of marmots and other secondary prey on livestock depredation rates, and testing the suitability of additional interventions, e.g., dogs and deterrents, as conflict mitigation tools. Our results will support wildlife managers in setting conservation priorities to promote the long-term co-existence of local people and snow leopards.

• Henrich, Maik; Hartig, Florian; Dormann, Carsten F.; Kühl, Hjalmar S.; Peters, Wibke & Franke, Frederik [Show all 9 contributors for this article] (2022). Deer Behavior Affects Density Estimates With Camera Traps, but Is Outwighted by Spatial Variability. Frontiers in Ecology and Evolution. 10. doi: 10.3389/fevo.2022.881502. Full text in Research Archive Show summary

  Density is a key trait of populations and an essential parameter in ecological research, wildlife conservation and management. Several models have been developed to estimate population density based on camera trapping data, including the random encounter model (REM) and camera trap distance sampling (CTDS). Both models need to account for variation in animal behavior that depends, for example, on the species and sex of the animals along with temporally varying environmental factors. We examined whether the density estimates of REM and CTDS can be improved for Europe’s most numerous deer species, by adjusting the behavior-related model parameters per species and accounting for differences in movement speeds between sexes, seasons, and years. Our results showed that bias through inadequate consideration of animal behavior was exceeded by the uncertainty of the density estimates, which was mainly influenced by variation in the number of independent observations between camera trap locations. The neglection of seasonal and annual differences in movement speed estimates for REM overestimated densities of red deer in autumn and spring by ca. 14%. This GPS telemetry-derived parameter was found to be most problematic for roe deer females in summer and spring when movement behavior was characterized by small-scale displacements relative to the intervals of the GPS fixes. In CTDS, density estimates of red deer improved foremost through the consideration of behavioral reactions to the camera traps (avoiding bias of max. 19%), while species-specific delays between photos had a larger effect for roe deer. In general, the applicability of both REM and CTDS would profit profoundly from improvements in their precision along with the reduction in bias achieved by exploiting the available information on animal behavior in the camera trap data.

• Busse, Annika; Cizek, Lukas; Čížkova, Pavla; Drag, Lukas; Dvorak, Vladimir & Foit, Jiří [Show all 18 contributors for this article] (2022). Forest dieback in a protected area triggers the return of the primeval forest specialist Peltis grossa (Coleoptera, Trogossitidae). Conservation Science and Practice (CSP). 4(2). doi: 10.1111/csp2.612. Full text in Research Archive Show summary

  Forest set-aside is a commonly employed conservation strategy, but large-scale disturbances regularly evoke discussions on its utility for biodiversity conservation in former production forests. In this study, we reconstructed the return of a primeval forest specialist, the beetle Peltis grossa (Linnaeus, 1758) of the family Trogossitidae, to two national parks after more than a century of absence. To illuminate historical processes and the role of potential refuges and species' size, we compared the beetle's current distribution collected in a large-scale citizen science approach, with historical data and the current distribution of two closely related, smaller species. We quantified deadwood preferences and investigated the effect of benign neglect versus salvage-logging management practices on P. grossa abundances. Our findings support the view that P. grossa survived in the southern Bohemian Forest, which enabled its recolonization of the landscapes. However, a build-up of the population was dependent upon a massive supply of deadwood by bark beetles within the refuge area. In a large area in the north of the study region that >20 years ago contained ample amounts of deadwood, forest succession outpaced colonization by P. grossa. The current probability of the species' presence decreased with distance to the presumed refuge area from 70% to 5% at 40 km. In the present core distribution area of P. grossa, salvage logging reduced its abundance by the factor 20. These results provide three important lessons on the potential of natural disturbances as a biodiversity restoration tool in forest set-asides: First, large supply of deadwood by disturbance can trigger the return of locally extinct primeval forest specialists. Second, the species must survive within a critical distance (for P. grossa < 10–40 km). Third, salvage logging significantly reduces the population densities of forest specialists by reducing habitat amount.

• Gatiso, Tsegaye T.; Kulik, Lars; Bachmann, Mona; Bonn, Aletta; Bösch, Lukas & Freytag, Andreas [Show all 12 contributors for this article] (2022). Sustainable protected areas: Synergies between biodiversity conservation and socioeconomic development. People and Nature. 4(4), p. 893–903. doi: 10.1002/pan3.10326. Full text in Research Archive Show summary

  1. Reconciling conservation and socioeconomic development goals is key to sustainability but remains a source of fierce debate. Protected areas (PAs) are believed to play an essential role in achieving these seemingly conflicting goals. Yet, there is limited evidence as to whether PAs are actually achieving the two goals simultaneously. 2. Here, we investigate when and to what extent synergies or trade-offs between biodiversity conservation and local socioeconomic development occur. To explore these relationships, we collected data across a wide range of socioeconomic settings through face-to- face survey with PA managers from 114 African and European PAs using structured questionnaire. 3. We found synergies between biodiversity conservation and socioeconomic development for 62% of the PAs, albeit with significant differences between African (55%) and European PAs (75%). Moreover, the sustainability of PAs in conserving biodiversity was strongly correlated with the empowerment of the PA management and the involvement of local communities in PA planning and decision-making processes. 4. Our results demonstrate that for PAs to promote synergies between biodiversity conservation and local socioeconomic development, and to enhance their longterm sustainability, they should invest in the empowerment of their respective management and involvement of local communities in their planning and management activities.

• Hummel, Herman; Kalle, Valerie; Bienfait, Louise; Boyer, Yolande; Heurich, Marco Dietmar & Svajda, Juraj [Show all 25 contributors for this article] (2022). A bottom-up practitioner-derived set of Essential Variables for Protected Area management. Environmental and Sustainability Indicators. 14. doi: 10.1016/j.indic.2022.100179. Full text in Research Archive Show summary

  Assessing the environmental status of Protected Areas (PAs) is a challenging issue. To indicate that status, the identification of a common set of variables that are scientifically sound, and easy to assess and monitor by the PA practitioners, is particularly important. In this study, a set of 27 Essential Variables (EVs) for PA management was selected in a bottom-up process from 67 harmonised variables that describe the status of Ecosystem Functions and Structures, Ecosystem Services, and Threats in PAs. This bottom-up process involved 27 internationally recognised PAs, mostly European, with different level of protection, different extent, and a wide range of human-nature interactions. The EVs were selected by more than 120 practitioners, i.e. PA managers and rangers, as well as scientists, working in terrestrial and aquatic PAs. Across both terrestrial and aquatic PAs, scientists and practitioners largely identified the same variables as important. Data availability for these 27 EVs varied between PAs and averaged 67% across all studied PAs. As this set of EVs for PAs is defined through a bottom-up approach considering variables already in use both in management and research, it is more than for previous EVs likely to be adopted, applied and developed to record the status and changes in the ecological and socio-economic conditions of PAs and to forecast future changes. Thereby, the EVs for PAs present a common vocabulary and tool to enhance in a uniform way the (inter)national communication, exchange and comparison of information on the status of PAs between policy makers, scientists and PA managers. The perceived status of the EVs, on an average 3.6 on a scale to a maximum of 5, indicates the surveyed PAs are in a moderate to good environmental condition. Moreover, the EVs for PAs form a cost- and time-efficient tool for PA managers to monitor developments in essential elements of their PAs, including the potential for Societal Goods and Benefits (SG&B), and to (pro-)actively tackle the potential threats that may arise in their area. Likewise, for policy makers EVs for PAs may support decision making on ecosystem management, spatial planning, and predictive modelling on the future status and requirements of PAs in their country or region.

• Orazi, Valerio; Hagge, Jonas; Gossner, Martin M.; Müller, Jörg & Heurich, Marco Dietmar (2022). A Biodiversity Boost From the Eurasian Beaver (Castor fiber) in Germany’s Oldest National Park. Frontiers in Ecology and Evolution. 10. doi: 10.3389/fevo.2022.873307. Full text in Research Archive Show summary

  Freshwater ecosystems are among the most threatened ecosystems on the planet. Beavers are important engineers in freshwater ecosystems and reintroduction programs have enabled the recovery of beaver populations in several European countries, but the impact on biodiversity conservation is still unclear. We studied the effects of beavers on the terrestrial biodiversity of eight taxonomic groups by comparing beaver ponds with river and forest habitats in a mountain forest ecosystem in Central Europe. Among the 1,166 collected species, 196 occurred exclusively at beaver ponds, 192 in plots at the river, and 156 in the forest plots. More species of conservation concern were found at the beaver ponds (76) than on the river (67) and forest (63) plots. Abundances of bats and birds were higher at the beaver ponds than at the river or forest sites. The number of bird species at the beaver ponds was higher than at the river. The community composition of birds, beetles, and true bugs differed significantly between the beaver ponds and river plots, and for seven taxonomic groups it differed significantly between the beaver ponds and forest plots. An indicator species analysis revealed eight indicator species for the beaver pond but none for the river and forest plots. Our results demonstrate that beavers, as ecological engineers, increase habitat heterogeneity in mountain forests and thereby promote biodiversity. The expansion of beaver populations into these ecosystems should thus be supported, as it may serve as a biotic restoration tool.

• Weiss, Fabio; Michler, Frank Uwe; Gillich, Benjamin; Tillmann, Jörg; Ciuti, Simone & Heurich, Marco Dietmar [Show all 7 contributors for this article] (2022). Displacement Effects of Conservation Grazing on Red Deer (Cervus elaphus) Spatial Behaviour. Environmental Management. ISSN 0364-152X. doi: 10.1007/s00267-022-01697-6. Full text in Research Archive Show summary

  Conservation grazing uses semi-feral or domesticated herbivores to limit encroachment in open areas and to promote biodiversity. However, we are still unaware of its effects on wild herbivores. This study investigates the influence of herded sheep and goats on red deer (Cervus elaphus) spatial behavior by testing three a-priori hypotheses: (i) red deer are expected to avoid areas used by livestock, as well as adjacent areas, when livestock are present, albeit (ii) red deer increase the use of these areas when sheep and goats are temporarily absent and (iii) there is a time-lagged disruption in red deer spatial behavior when conservation grazing practice ends. Using GPS-telemetry data on red deer from a German heathland area, we modelled their use of areas grazed by sheep and goats, using mixed-effect logistic regression. Additionally, we developed seasonal resource selection functions (use-availability design) to depict habitat selection by red deer before, during, and after conservation grazing. Red deer used areas less during conservation grazing throughout all times of the day and there was no compensatory use during nighttime. This effect mostly persisted within 21 days after conservation grazing. Effects on habitat selection of red deer were detectable up to 3000 meters away from the conservation grazing sites, with no signs of either habituation or adaption. For the first time, we demonstrate that conservation grazing can affect the spatio-temporal behavior of wild herbivores. Our findings are relevant for optimizing landscape and wildlife management when conservation grazing is used in areas where wild herbivores are present.

• Bachmann, Mona Estrella; Kulik, Lars; Gatiso, Tsegaye T.; Nielsen, Martin Reinhardt; Haase, Dagmar & Heurich, Marco Dietmar [Show all 19 contributors for this article] (2022). Analysis of differences and commonalities in wildlife hunting across the Africa-Europe South-North gradient. PLoS Biology. ISSN 1544-9173. 20(8). doi: 10.1371/journal.pbio.3001707. Full text in Research Archive Show summary

  Hunting and its impacts on wildlife are typically studied regionally, with a particular focus on the Global South. Hunting can, however, also undermine rewilding efforts or threaten wildlife in the Global North. Little is known about how hunting manifests under varying socioeconomic and ecological contexts across the Global South and North. Herein, we examined differences and commonalities in hunting characteristics across an exemplary Global South-North gradient approximated by the Human Development Index (HDI) using face-to-face interviews with 114 protected area (PA) managers in 25 African and European countries. Generally, we observed that hunting ranges from the illegal, economically motivated, and unsustainable hunting of herbivores in the South to the legal, socially and ecologically motivated hunting of ungulates within parks and the illegal hunting of mainly predators outside parks in the North. Commonalities across this Africa-Europe South-North gradient included increased conflict-related killings in human-dominated landscapes and decreased illegal hunting with beneficial community conditions, such as mutual trust resulting from community involvement in PA management. Nevertheless, local conditions cannot outweigh the strong effect of the HDI on unsustainable hunting. Our findings highlight regional challenges that require collaborative, integrative efforts in wildlife conservation across actors, while identified commonalities may outline universal mechanisms for achieving this goal.

• Sunde, Peter; Böcker, Felix; Rauset, Geir Rune; Kjellander, Petter; Chrenkova, Monika & Skovdal, Trine Munck [Show all 9 contributors for this article] (2022). Mammal responses to predator scents across multiple study areas. Ecosphere. 13(8). doi: 10.1002/ecs2.4215. Full text in Research Archive Show summary

  Antipredator behaviors allow prey to mitigate the impacts of their predators. We investigated antipredator responses of two herbivore species, roe deer and European hare, and one mesopredator, red fox, toward predation risk imposed by lynx and wolf. We collected data (using camera traps) on visitation fre quency and vigilance behavior to olfactory predator stimuli during 158 stan dardized scent trials in five areas across Europe, where lynx and wolves either occurred or had been absent for centuries. After a period without scent, trial sites were either marked with lynx or wolf urine, or butyric acid (unspecific scent used to contrast species-specific scent responses). We expected the two herbivores to respond aversively (reduced visitation frequency, and increased vigilance) to predator urine, while red foxes (scavengers) might adopt a risk-sensitive exploration strategy by increasing vigilance near predator urine without reducing visitation frequency. For all species, we expected stronger responses toward the ambush predator lynx than to the pursue predator wolf (cryptic predator hypothesis). If prey responds more strongly to predator stim uli when coexisting with the predator, we expected stronger reactions to preda tor urine in areas where predators occurred (naïve prey hypothesis). Roe deer significantly avoided lynx urine and butyric acid, but not wolf urine. However, roe deer visitation frequency did not differ between scent treatment with largecarnivore urine and butyric acid (suggesting that roe deer generally avoid areas with unfamiliar scent), or between areas where large carnivores were present and absent. Hares did not significantly avoid predator urine. Red foxes were attracted to lynx urine in sympatry, but not in allopatry with large carnivores. They increased vigilance rates in the presence of lynx urine independent of sympatry/ allopatry with large carnivores. These findings generally confirm our expectations of predator avoidance by herbivores, and attraction combined with increased vigi lance of mesopredators. In all species, lynx urine elicited stronger responses than wolf urine (although not significantly different), which to some extent conforms to the cryptic predator hypothesis. We found no support for the naïve prey hypothesis. However, higher attraction of red foxes to lynx urine in sympatric situ ations might indicate that positive responses by scavengers are learning based. antipredator behavior, avoidance, Canis lupus, Capreolus capreolus, intra-guild predation, landscapes of fear, Lepus europaeus, Lynx lynx, odor, risk-sensitive foraging, vigilance, Vulpes vulpes

• Zong, Xin; Wang, Tiejun; Skidmore, Andrew K. & Heurich, Marco Dietmar (2022). LiDAR reveals a preference for intermediate visibility by a forest-dwelling ungulate species. Journal of Animal Ecology. ISSN 0021-8790. doi: 10.1111/1365-2656.13847. Full text in Research Archive Show summary

  Abstract 1. Visibility (viewshed) plays a significant and diverse role in animals' behaviour and fitness. Understanding how visibility influences animal behaviour requires the measurement of habitat visibility at spatial scales commensurate to individual animal choices. However, measuring habitat visibility at a fine spatial scale over a landscape is a challenge, particularly in highly heterogeneous landscapes (e.g. forests). As a result, our ability to model the influence of fine-scale visibility on animal behaviour has been impeded or limited. 2. In this study, we demonstrate the application of the concept of three-dimensional (3D) cumulative viewshed in the study of animal spatial behaviour at a landscape level. Specifically, we employed a newly described approach that combines ter-restrial and airborne light detection and ranging (LiDAR) to measure fine-scale habitat visibility (3D cumulative viewshed) on a continuous scale in forested landscapes. We applied the LiDAR-derived visibility to investigate how visibility in forests affects the summer habitat selection and the movement of 20 GPS- collared female red deer Cervus elaphus in a temperate forest in Germany. We used integrated step selection analysis to determine whether red deer show any preference for fine-scale habitat visibility and whether visibility is related to the rate of movement of red deer. 3. We found that red deer selected intermediate habitat visibility. Their preferred level of visibility during the day was substantially lower than that of night and twilight, whereas the preference was not significantly different between night and twilight. In addition, red deer moved faster in high-visibility areas, possibly mainly to avoid predation and anthropogenic risk. Furthermore, red deer moved most rapidly between locations in the twilight. 4. For the first time, the preference for intermediate habitat visibility and the adap-tion of movement rate to fine-scale visibility by a forest-dwelling ungulate spe-cies at a landscape scale was revealed. The LiDAR technique used in this study offers fine-scale habitat visibility at the landscape level in forest ecosystems, which would be of broader interest in the fields of animal ecology and behaviour.

• Mattisson, Jenny; Linnell, John Durrus; Anders, Ole; Belotti, Elisa; Breitenmoser-Würsten, Christine & Bufka, Ludek [Show all 25 contributors for this article] (2022). Timing and synchrony of birth in Eurasian lynx across Europe. Ecology and Evolution. 12(8). doi: 10.1002/ece3.9147. Full text in Research Archive Show summary

  The Eurasian lynx (Lynx lynx) occurs across the Eurasian continent, covering three of the four main climate regions of the world. Thus, their distribution includes a large variation in climatic conditions, making it an ideal species to explore reproductive phenology. Here, we used data on multiple reproductive events from 169 lynx females across Europe. Mean birth date was May 28 (April 23 to July 1), but was ~10 days later in northern Europe than in central and southern Europe. Birth dates were relatively synchronized across Europe, but more so in the north than in the south. Timing of birth was delayed by colder May temperatures. Severe and cold weather may affect neonatal survival via hypothermia and avoiding inclement weather early in the season may select against early births, especially at northern latitudes. Overall, only about half of the kittens born survived until onset of winter but whether kittens were born relatively late or early did not affect kitten survival. Lynx are strict seasonal breeders but still show a degree of flexibility to adapt the timing of birth to surrounding environmental conditions. We argue that lynx give birth later when exposed to colder spring temperatures and have more synchronized births when the window of favorable conditions for raising kittens is shorter. This suggests that lynx are well adapted to different environmental conditions, from dry and warm climates to alpine, boreal, and arctic climates. This variation in reproductive timing will be favorable in times of climate change, as organisms with high plasticity are more likely to adjust to new environmental conditions.

• Smith, Adam F.; Ciuti, Simone; Shamovich, Dmitry; Fenchuk, Viktar; Zimmermann, Barbara & Heurich, Marco Dietmar (2022). Quiet islands in a world of fear: Wolves seek core zones of protected areas to escape human disturbance. Biological Conservation. ISSN 0006-3207. 276. doi: 10.1016/j.biocon.2022.109811. Full text in Research Archive Show summary

  The Anthropocene continuously escalates the challenges and threats faced by large carnivores in human-dominated landscapes. Given their unique conservation and management requirements, detailed insights into their behaviour in relation to human-induced risks are crucial to designing landscapes of coexistence for people and predators, containing key features such as nature conservation areas. Adaptations like selection or avoidance of areas at certain times reveal the dynamic perception of large carnivores to risk-landscapes and the trade-offs with potential resources. This study investigates these ideas by applying a habitat-selection approach to GPS collared wolves in Belovezhskaya Pushcha National Park (Belarus) to quantify fine-scale avoidance of human disturbance. Our results indicate that wolves selected strongly for areas of higher nature protection within the national park. They also avoided human disturbance from settlements and roads, but mediated their behaviour depending on the shifting risk throughout the day and night. They selected for more open areas during darkness. Seasonal and sex-based differences shifted avoidance, such as females being more avoidant of settlements. This suggests evidence of a successful anti-predator strategy against humans. Our study offers some of the most detailed and novel insights into wolf spatio-temporal avoidance of disturbance in the context of protected areas, which is imperative for fine-tuning management measures for continued coexistence and effective conservation of this functionally important species.

• Filla, Marc; Lama, Rinzin Phunjok; Filla, Tim; Heurich, Marco Dietmar; Balkenhol, Niko & Waltert, Matthias [Show all 7 contributors for this article] (2022). Patterns of livestock depredation by snow leopards and effects of intervention strategies: Lessons from the Nepalese Himalaya. Wildlife research (East Melbourne). ISSN 1035-3712. doi: 10.1071/WR21169. Full text in Research Archive Show summary

  Context: Large carnivores are increasingly threatened by anthropogenic activities, and their protection is among the main goals of biodiversity conservation. The snow leopard (Panthera uncia) inhabits high-mountain landscapes where livestock depredation drives it into conflicts with local people and poses an obstacle for its conservation. Aims: The aim of this study was to identify the livestock groups most vulnerable to depredation, target them in implementation of practical interventions, and assess the effectiveness of intervention strategies for conflict mitigation. We present a novel attempt to evaluate intervention strategies for particularly vulnerable species, age groups, time, and seasons. Methods: In 2020, we conducted questionnaire surveys in two regions of the Annapurna Conservation Area, Nepal (Manang, n = 146 respondents and Upper Mustang, n = 183). We applied sample comparison testing, Jacobs’ selectivity index, and generalised linear models (GLMs) to assess rates and spatio-temporal heterogeneity of depredation, reveal vulnerable livestock groups, analyse potential effects of applied intervention strategies, and identify husbandry factors relevant to depredation. Key results: Snow leopard predation was a major cause of livestock mortality in both regions (25.4–39.8%), resulting in an estimated annual loss of 3.2–3.6% of all livestock. The main intervention strategies (e.g. corrals during night-time and herding during daytime) were applied inconsistently and not associated with decreases in reported livestock losses. In contrast, we found some evidence that dogs, deterrents (light, music playing, flapping tape, and dung burning), and the use of multiple interventions were associated with a reduction in reported night-time depredation of yaks. Conclusions and implications: We suggest conducting controlled randomised experiments for quantitative assessment of the effectiveness of dogs, deterrents, and the use of multiple interventions, and widely applying the most effective ones in local communities. This would benefit the long-term co-existence of snow leopards and humans in the Annapurna region and beyond.

• Sani-Mohammed, Abubakar; Yao, Wei & Heurich, Marco Dietmar (2022). Instance segmentation of standing dead trees in dense forest from aerial imagery using deep learning. ISPRS Journal of Photogrammetry and Remote Sensing (P&RS). ISSN 0924-2716. 6. doi: 10.1016/j.ophoto.2022.100024. Full text in Research Archive Show summary

  Mapping standing dead trees, especially, in natural forests is very important for evaluation of the forest's health status, and its capability for storing Carbon, and the conservation of biodiversity. Apparently, natural forests have larger areas which renders the classical field surveying method very challenging, time-consuming, labor-intensive, and unsustainable. Thus, for effective forest management, there is the need for an automated approach that would be cost-effective. With the advent of Machine Learning, Deep Learning has proven to successfully achieve excellent results. This study presents an adjusted Mask R-CNN Deep Learning approach for detecting and segmenting standing dead trees in a mixed dense forest from CIR aerial imagery using a limited (195 images) training dataset. First, transfer learning is considered coupled with the image augmentation technique to leverage the limitation of training datasets. Then, we strategically selected hyperparameters to suit appropriately our model's architecture that fits well with our type of data (dead trees in images). Finally, to assess the generalization capability of our model's performance, a test dataset that was not confronted to the deep neural network was used for comprehensive evaluation. Our model recorded promising results reaching a mean average precision, average recall, and average F1-Score of 0.85, 0.88, and 0.87 respectively, despite our relatively low resolution (20 cm) dataset. Consequently, our model could be used for automation in standing dead tree detection and segmentation for enhanced forest management. This is equally significant for biodiversity conservation, and forest Carbon storage estimation.

• Barta, Karola Anna; Hais, Martin & Heurich, Marco Dietmar (2022). Characterizing forest disturbance and recovery with thermal trajectories derived from Landsat time series data. Remote Sensing of Environment. ISSN 0034-4257. 282. doi: 10.1016/j.rse.2022.113274. Full text in Research Archive Show summary

  The increasing frequency of forest disturbances caused by climate change has highlighted the importance of understanding the entire process of disturbance, from its onset to forest recovery. Many previous studies have used multispectral Landsat time-series data describing forest dynamics. However, there is a lack of studies using thermal imagery, which may provide information about bio-climatic changes and energy balance during the forest disturbance and recovery. Our objective in this research was to detect the main features of insect forest disturbance and subsequent forest recovery (disturbance duration, disturbance severity, recovery duration) using thermal Landsat imagery. We also aimed to determine the relationship between the identified thermal features and topography. The study area was a Norway spruce (Picea abies [L.] Karst.) dominated forest located in a Central European border region between the Czech Republic (Šumava Mountains) and Germany (Bavarian Forest). For more than three decades, forests in this area have experienced widespread defoliation due to the spruce bark beetle (Ips typographus L.). We determined the forest's surface temperature (ST) between 1985 and 2015 from thermal Landsat time-series data and then normalized it (STn) to be comparable across the years in question. We plotted thermal trajectories for this period and then clustered them based on their variances. The resulting thermal trajectories well described both disturbance and recovery, showing a rise in the STn during the onset of the disturbance, the severity, and a decrease during recovery. The mean disturbance duration was 8.44 years (SD = ±3.775), with a maximum severity as indicated by the STn of 4.92 (SD = ±1.5) and a duration of 12.84 years (SD = ±3.38) until 50% recovery and 17.85 years (SD = ±1.74) until 80% recovery. Clustering of the thermal trajectories revealed clusters with similar year-groups of bark beetle attack and a spatially aggregated pattern closely related to topography. Severity showed a positive correlation with altitude, whereas the spatially aggregated patterns of disturbance and recovery duration can be attributed to more complex topographical characteristics. Our study demonstrates the ability of thermal infrared imagery to provide highly relevant data for assessing not only the main features of forest disturbance and recovery, but also bio-climatic canopy functions in terms of topography and other environmental variables.

• Ripari, Lucia; Premier, Joe; Belotti, Elisa; Bluhm, Hendrik; Breitenmoser-Würsten, Christine & Bufka, Luděk [Show all 23 contributors for this article] (2022). Human disturbance is the most limiting factor driving habitat selection of a large carnivore throughout Continental Europe. Biological Conservation. ISSN 0006-3207. 266. doi: 10.1016/j.biocon.2021.109446. Full text in Research Archive Show summary

  Habitat selection is a multi-scale process driven by trade-offs between benefits, such as resource abundance, and disadvantages, such as the avoidance of risk. The latter includes human disturbances, to which large carnivores, with their large spatial requirements, are especially sensitive. We investigated the ecological processes underlying multi-scale habitat selection of a large carnivore, namely Eurasian lynx, across European landscapes characterized by different levels of human modification. Using a unique dataset of 125 lynx from 9 study sites across Europe, we compared used and available locations within landscape and home-range scales using a novel Mixed Effect randomForest approach, while considering environmental predictors as proxies for human disturbances and environmental resources. At the landscape scale, lynx avoided roads and human settlements, while at the home-range scale natural landscape features associated with shelter and prey abundance were more important. The results showed sex was of relatively low variable importance for lynx's general habitat selection behaviour. We found increasingly homogeneous responses across study sites with finer selection scales, suggesting that study site differences determined coarse selection, while utilization of resources at the finer selection scale was broadly universal. Thereby describing lynx's requirement, if not preference, for heterogeneous forests and shelter from human disturbances and implying that regional differences in coarse-scale selection are driven by availability rather than preference. These results provide crucial information for conserving this species in human-dominated landscapes, as well as for the first time, to our knowledge, generalising habitat selection behaviour of a large carnivore species at a continental scale.

• Duncanson, Laura; Kellner, James R.; Armston, John; Dubayah, Ralph; Minor, David M. & Hancock, Steven [Show all 118 contributors for this article] (2022). Aboveground biomass density models for NASA's Global Ecosystem Dynamics Investigation (GEDI) lidar mission. Remote Sensing of Environment. ISSN 0034-4257. 270. doi: 10.1016/j.rse.2021.112845. Full text in Research Archive Show summary

  NASA’s Global Ecosystem Dynamics Investigation (GEDI) is collecting spaceborne full waveform lidar data with a primary science goal of producing accurate estimates of forest aboveground biomass density (AGBD). This paper presents the development of the models used to create GEDI’s footprint-level (~25 m) AGBD (GEDI04_A) product, including a description of the datasets used and the procedure for final model selection. The data used to fit our models are from a compilation of globally distributed spatially and temporally coincident field and airborne lidar datasets, whereby we simulated GEDI-like waveforms from airborne lidar to build a calibration database. We used this database to expand the geographic extent of past waveform lidar studies, and divided the globe into four broad strata by Plant Functional Type (PFT) and six geographic regions. GEDI’s waveform-to-biomass models take the form of parametric Ordinary Least Squares (OLS) models with simulated Relative Height (RH) metrics as predictor variables. From an exhaustive set of candidate models, we selected the best input predictor variables, and data transformations for each geographic stratum in the GEDI domain to produce a set of comprehensive predictive footprint-level models. We found that model selection frequently favored combinations of RH metrics at the 98th, 90th, 50th, and 10th height above ground-level percentiles (RH98, RH90, RH50, and RH10, respectively), but that inclusion of lower RH metrics (e.g. RH10) did not markedly improve model performance. Second, forced inclusion of RH98 in all models was important and did not degrade model performance, and the best performing models were parsimonious, typically having only 1-3 predictors. Third, stratification by geographic domain (PFT, geographic region) improved model performance in comparison to global models without stratification. Fourth, for the vast majority of strata, the best performing models were fit using square root transformation of field AGBD and/or height metrics. There was considerable variability in model performance across geographic strata, and areas with sparse training data and/or high AGBD values had the poorest performance. These models are used to produce global predictions of AGBD, but will be improved in the future as more and better training data become available.

• Khorozyan, Igor & Heurich, Marco Dietmar (2022). Large-Scale Sheep Losses to Wolves (Canis lupus) in Germany Are Related to the Expansion of the Wolf Population but Not to Increasing Wolf Numbers. Frontiers in Ecology and Evolution. 10. doi: 10.3389/fevo.2022.778917. Full text in Research Archive Show summary

  Recovery of predator populations triggers conflicts due to livestock depredation losses, particularly in Germany where the wolf (Canis lupus) population grows exponentially and livestock (especially sheep) losses raise public concerns and motivate the authorities to control wolf numbers. Yet, the effects of wolf numbers and alternative factors, such as abundance of prey and livestock, on livestock losses in this country are not investigated. In this study, we collected and analyzed data on the numbers of reproductive units of wolves (packs and pairs together) as a surrogate of adult wolf numbers, sheep killed by wolves, living sheep, red deer (Cervus elaphus), roe deer (Capreolus capreolus), and wild boar (Sus scrofa) in every German state and year from 2002 to 2019. We applied a negative binomial Generalized Linear Mixed Model (GLMM) to estimate the effects of these predictors on the numbers of sheep killed by wolves. We also examined the relationships between the percentages of killed/living sheep and the numbers of living sheep. Ranking of 63 models based on the Akaike information criterion revealed that sheep losses were determined by state, year, and number of living sheep, not by wolf numbers, at high precision and accuracy. The number of sheep killed by wolves increased consistently by 41% per year and by 30% for every additional 10,000 sheep, mainly in the north where most wolf territories are concentrated. This means that sheep are protected insufficiently and/or ineffectively. The percentages of killed/living sheep consistently increased by 0.02–0.05% per state and year, with the maximum percentage of 0.7%, on a backdrop of decreasing numbers of living sheep. In conclusion, we demonstrate that sheep losses in Germany have been driven by the expansion of the wolf population, not by wolf numbers, and by the number of sheep available. We suggest that Germany’s wolf conservation policy should focus on alternative nonlethal interventions, enforcement and standardization of intervention monitoring, and promotion of wolf tolerance rather than on lethal control of wolf population size.

• Alagialoglou, Leonidas; Manakos, Ioannis; Heurich, Marco Dietmar; Cervenka, Jaroslav & Delopoulos, Anastasios (2022). A Learnable Model with Calibrated Uncertainty Quantification for Estimating Canopy Height from Spaceborne Sequential Imagery. IEEE Transactions on Geoscience and Remote Sensing. ISSN 0196-2892. 60. doi: 10.1109/TGRS.2022.3171407. Full text in Research Archive Show summary

  Global-scale canopy height mapping is an important tool for ecosystem monitoring and sustainable forest management. Various studies have demonstrated the ability to estimate canopy height from a single spaceborne multispectral image using end-to-end learning techniques. In addition to texture information of a single-shot image, our study exploits multitemporal information of image sequences to improve estimation accuracy. We adopt a convolutional variant of a long short-term memory (LSTM) model for canopy height estimation from multitemporal instances of Sentinel-2 products. Furthermore, we utilize the deep ensembles technique for meaningful uncertainty estimation on the predictions and postprocessing isotonic regression model for calibrating them. Our lightweight model ( ∼320k trainable parameters) achieves the mean absolute error (MAE) of 1.29 m in a European test area of 79 km2 . It outperforms the state-of-the-art methods based on single-shot spaceborne images as well as costly airborne images while providing additional confidence maps that are shown to be well calibrated. Moreover, the trained model is shown to be transferable in a different country of Europe using a fine-tuning area of as low as ∼2 km2 with MAE=1.94m.

• Broekman, Maarten J. E.; Hilbers, Jelle P.; Huijbregts, Mark A. J.; Mueller, Thomas; Ali, Abdullah H. & Andrén, Henrik [Show all 88 contributors for this article] (2022). Evaluating expert-based habitat suitability information of terrestrial mammals with GPS-tracking data. Global Ecology and Biogeography. ISSN 1466-822X. 31(8), p. 1526–1541. doi: 10.1111/geb.13523. Full text in Research Archive Show summary

  Aim: Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert- based informa-tion is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert- based in-formation with detailed empirical evidence. Here, we compared expert- based habitat suitability information from the International Union for Conservation of Nature (IUCN) with habitat suitability information derived from GPS-tracking data of 1,498 individu-als from 49 mammal species.Location: Worldwide.Time period: 1998–2021.Major taxa studied: Forty- nine terrestrial mammal species.Methods: Using GPS data, we estimated two measures of habitat suitability for each individual animal: proportional habitat use (proportion of GPS locations within a habi-tat type), and selection ratio (habitat use relative to its availability). For each individual we then evaluated whether the GPS- based habitat suitability measures were in agree-ment with the IUCN data. To that end, we calculated the probability that the ranking of empirical habitat suitability measures was in agreement with IUCN's classification into suitable, marginal and unsuitable habitat types.Results: IUCN habitat suitability data were in accordance with the GPS data (> 95% probability of agreement) for 33 out of 49 species based on proportional habitat use estimates and for 25 out of 49 species based on selection ratios. In addition, 37 and 34 species had a > 50% probability of agreement based on proportional habitat use and selection ratios, respectively.Main conclusions: We show how GPS-tracking data can be used to evaluate IUCN habitat suitability data. Our findings indicate that for the majority of species in-cluded in this study, it is appropriate to use IUCN habitat suitability data in macro-ecological studies. Furthermore, we show that GPS-tracking data can be used to identify and prioritize species and habitat types for re-evaluation of IUCN habitat suitability data expert opinion, GPS, habitat suitability, habitat type, habitat use, IUCN, mammals, movement, selection ratio, telemetry

• Oliveira, Teresa; Sanchez, David Carricondo; Mattisson, Jenny; Vogt, Kristina; Corradini, Andrea & Linnell, John Durrus [Show all 10 contributors for this article] (2022). Predicting kill sites of an apex predator from GPS data in different multi-prey systems. Ecological Applications. ISSN 1051-0761. doi: 10.1002/eap.2778. Full text in Research Archive Show summary

  Kill rates are a central parameter to assess the impact of predation on preyspecies. An accurate estimation of kill rates requires a correct identificationof kill sites, often achieved by field-checking GPS location clusters (GLCs).However, there are potential sources of error included in kill-site identifica-tion, such as failing to detect GLCs that are kill sites, and misclassifying thegenerated GLCs (e.g., kill for nonkill) that were not field checked. Here, weaddress these two sources of error using a large GPS dataset of collared Eur-asian lynx (Lynx lynx), an apex predator of conservation concern in Europe, inthree multiprey systems, with different combinations of wild, semidomestic,and domestic prey. We first used a subsampling approach to investigate howdifferent GPS-fix schedules affected the detection of GLC-indicated kill sites.Then, we evaluated the potential of the random forest algorithm to classifyGLCs as nonkills, small prey kills, and ungulate kills. We show that thenumber of fixes can be reduced from seven to three fixes per night withoutmissing more than 5% of the ungulate kills, in a system composed of wild prey.Reducing the number of fixes per 24 h decreased the probability of detectingGLCs connected with kill sites, particularly those of semidomestic or domesticprey, and small prey. Random forest successfully predicted between 73%–90%of ungulate kills, but failed to classify most small prey in all systems, withsensitivity (true positive rate) lower than 65%. Additionally, removingdomestic prey improved the algorithm’s overall accuracy. We provide a setof recommendations for studies focusing on kill-site detection that can beconsidered for other large carnivore species in addition to the Eurasian lynx.We recommend caution when working in systems including domestic prey,as the odds of underestimating kill rates are higher.domestic prey, Eurasian lynx, GPS location clusters (GLCs), GPS-fix schedule, kill sites,multiprey system, random forest

• Niedballa, Jürgen; Axtner, Jan; Döbert, Timm Fabian; Tilker, Andrew; Nguyen, An & Wong, Seth T. [Show all 9 contributors for this article] (2022). imageseg: An R package for deep learning-based image segmentation. Methods in Ecology and Evolution. 13(11), p. 2363–2371. doi: 10.1111/2041-210X.13984. Full text in Research Archive Show summary

  Convolutional neural networks (CNNs) and deep learning are powerful and robust tools for ecological applications and are particularly suited for image data. Image segmentation (the classification of all pixels in images) is one such application and can, for example, be used to assess forest structural metrics. While CNN-based image segmentation methods for such applications have been suggested, widespread adoption in ecological research has been slow, likely due to technical difficulties in implementation of CNNs and lack of toolboxes for ecologists. Here, we present R package imageseg which implements a CNN-based workflow for general purpose image segmentation using the U-Net and U-Net++ architectures in R. The workflow covers data (pre)processing, model training and predictions. We illustrate the utility of the package with image recognition models for two forest structural metrics: tree canopy density and understorey vegetation density. We trained the models using large and diverse training datasets from a variety of forest types and biomes, consisting of 2877 canopy images (both canopy cover and hemispherical canopy closure photographs) and 1285 understorey vegetation images. Overall segmentation accuracy of the models was high with a Dice score of 0.91 for the canopy model and 0.89 for the understorey vegetation model (assessed with 821 and 367 images respectively). The image segmentation models performed significantly better than commonly used thresholding methods and generalized well to data from study areas not included in training. This indicates robustness to variation in input images and good generalization strength across forest types and biomes. The package and its workflow allow simple yet powerful assessments of forest structural metrics using pretrained models. Furthermore, the package facilitates custom image segmentation with single or multiple classes and based on colour or grayscale images, for example, for applications in cell biology or for medical images. Our package is free, open source and available from CRAN. It will enable easier and faster implementation of deep learning-based image segmentation within R for ecological applications and beyond.

• Salvatori, M.; Groeve, Groeve De; Loon, Loon van; Baets, Baets De; Morellet, N. & Focardi, S. [Show all 17 contributors for this article] (2022). Day versus night use of forest by red and roe deer as determined by Corine Land Cover and Copernicus Tree Cover Density: assessing use of geographic layers in movement ecology. Landscape Ecology. ISSN 0921-2973. 37, p. 1453–1468. doi: 10.1007/s10980-022-01416-w. Full text in Research Archive Show summary

  Context Diel use of forest and open habitats by large herbivores is linked to species-specifc needs of multiple and heterogeneous resources. However, forest cover layers might deviate considerably for a given landscape, potentially afecting evaluations of animals’ habitat use. Objectives We assessed inconsistency in the estimates of diel forest use by red and roe deer at GPS location and home range (HR) levels, using two geographic layers: Tree Cover Density (TCD) and Corine Land Cover (CLC). Methods We frst measured the classifcation mismatch of red and roe deer GPS locations between TCD and CLC, also with respect to habitat units’ size. Then, we used Generalised Least Squares models to assess the proportional use of forest at day and night at the GPS location and HR levels, both with TCD and CLC. Results About 20% of the GPS locations were inconsistently classifed as forest or open habitat by the two layers, particularly within smaller habitat units. Overall proportion of forest and open habitat, though, was very similar for both layers. In all populations, both deer species used forest more at day than at night and this pattern was more evident with TCD than with CLC. However, at the HR level, forest use estimates were only marginally diferent between the two layers. Conclusions When estimating animal habitat use, geographic layer choice requires careful evaluation with respect to ecological questions and target species. Habitat use analyses based on GPS locations are more sensitive to layer choice than those based on home ranges.

• Heurich, Marco Dietmar (2021). Minimizing the Annotation Effort for Detecting Wildlife in Camera Trap Images with Active Learning. GI-Edition Lecture Notes in Informatics (LNI). ISSN 1617-5468. doi: 10.18420/informatik2021-042. Full text in Research Archive
• Bergvall, Ulrika A.; Morellet, Nicolas; Kjellander, Petter; Rauset, Geir R.; Groeve, Johannes De & Borowik, Tomasz [Show all 16 contributors for this article] (2021). Settle down! ranging behaviour responses of roe deer to different capture and release methods. Animals. 11(11). doi: 10.3390/ani11113299. Full text in Research Archive Show summary

  Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step fThe fitting of tracking devices to wild animals requires capture and handling which causes stress and can potentially cause injury, behavioural modifications that can affect animal welfare and the output of research. We evaluated post capture and release ranging behaviour responses of roe deer (Capreolus capreolus) for five different capture methods. We analysed the distance from the centre of gravity and between successive locations, using data from 14 different study sites within the EURODEER collaborative project. Independently of the capture method, we observed a shorter distance between successive locations and contextual shift away from the home range centre of gravity after the capture and release event. However, individuals converged towards the average behaviour within a relatively short space of time (between 10 days and one month). If researchers investigate questions based on the distance between successive locations of the home range, we recommend (1) initial investigation to establish when the animals start to behave normally again or (2) not using the first two to three weeks of data for their analysis. We also encourage researchers to continually adapt methods to minimize stress and prioritize animal welfare wherever possible, according to the Refinement of the Three R’s. box trap; Capreolus capreolus; net drives; net trap; roe deer; 3R’s

• Passoni, Gioele; Coulson, Tim; Ranc, Nathan; Corradini, Andrea; Hewison, A. J. Mark & Ciuti, Simone [Show all 13 contributors for this article] (2021). Roads constrain movement across behavioural processes in a partially migratory ungulate. Movement Ecology. 9(57), p. 1–12. doi: 10.1186/s40462-021-00292-4. Full text in Research Archive Show summary

  Background: Human disturbance alters animal movement globally and infrastructure, such as roads, can act as physical barriers that impact behavior across multiple spatial scales. In ungulates, roads can particularly hamper key ecological processes such as dispersal and migration, which ensure functional connectivity among populations, and may be particularly important for population performance in highly human-dominated landscapes. The impact of roads on some aspects of ungulate behavior has already been studied. However, potential differences in response to roads during migration, dispersal and home range movements have never been evaluated. Addressing these issues is particularly important to assess the resistance of European landscapes to the range of wildlife movement processes, and to evaluate how animals adjust to anthropogenic constraints. Methods: We analyzed 95 GPS trajectories from 6 populations of European roe deer (Capreolus capreolus) across the Alps and central Europe. We investigated how roe deer movements were affected by landscape characteristics, including roads, and we evaluated potential differences in road avoidance among resident, migratory and dispersing animals (hereafter, movement modes). First, using Net Squared Displacement and a spatio-temporal clustering algorithm, we classified individuals as residents, migrants or dispersers. We then identified the start and end dates of the migration and dispersal trajectories and retained only the GPS locations that fell between those dates (i.e., during transience). Finally, we used the resulting trajectories to perform an integrated step selection analysis. Results: We found that roe deer moved through more forested areas during the day and visited less forested areas at night. They also minimized elevation gains and losses along their movement trajectories. Road crossings were strongly avoided at all times of day, but when they occurred, they were more likely to occur during longer steps and in more forested areas. Road avoidance did not vary among movement modes, and during dispersal and migration, it remained high and consistent with that expressed during home range movements. Conclusions: Roads can represent a major constraint to movement across modes and populations, potentially limiting functional connectivity at multiple ecological scales. In particular, they can affect migrating individuals that track seasonal resources, and dispersing animals searching for novel ranges

• Calkoen, Suzanne T. S. van Beeck; Kreikenbohm, Rebekka; Kuijper, Dries P. J. & Heurich, Marco Dietmar (2021). Olfactory cues of large carnivores modify red deer behavior and browsing intensity. Behavioral Ecology. ISSN 1045-2249. 32(5), p. 982–992. doi: 10.1093/beheco/arab071. Full text in Research Archive Show summary

  This study examined the effect of perceived predation risk imposed by lynx (Lynx lynx) and wolf (Canis lupus) on red deer (Cervus elaphus) foraging behavior under experimental conditions. We hypothesized that in response to large carnivore scent red deer would increase their vigilance, although reducing the frequency and duration of visits to foraging sites. Consequently, browsing intensity on tree saplings was expected to decrease, whereas a higher proportion of more preferred species was expected to be browsed to compensate for higher foraging costs. We expected stronger responses towards the ambush predator lynx, compared with the cursorial predator wolf. These hypotheses were tested in a cafeteria experiment conducted within three red deer enclosures, each containing four experimental plots with olfactory cues of wolf, lynx, cow, and water as control. On each plot, a camera trap was placed and browsing intensity was measured for one consecutive week, repeated three times. Red deer reduced their visitation duration and browsing intensity on plots with large carnivore scent. Despite red deer showing a clear preference for certain tree species, the presence of large carnivore scent did not change selectivity towards different tree species. Contrary to our hypothesis, we found more pronounced effects of wolf (cursorial) compared with lynx (ambush). This study is the first to experimentally assess the perceived risk effects on the red deer foraging behavior of large carnivores differing in hunting modes. Our findings provide insights into the role of olfactory cues in predator-prey interactions and how they can modify fine-scale herbivore-plant interactions.

• Risely, Alice; Gillingham, Mark A.F.; Bechet, Arnaud; Brändel, Stefan; Heni, Alezander C. & Heurich, Marco Dietmar [Show all 11 contributors for this article] (2021). Phylogeny-and abundance-based metrics allow for the consistent comparison of core gut microbiome diversity indices across host species. Frontiers in Microbiology. 12(5). doi: 10.3389/fmicb.2021.659918. Full text in Research Archive Show summary

  The filtering of gut microbial datasets to retain high prevalence taxa is often performed to identify a common core gut microbiome that may be important for host biological functions. However, prevalence thresholds used to identify a common core are highly variable, and it remains unclear how they affect diversity estimates and whether insights stemming from core microbiomes are comparable across studies. We hypothesized that if macroecological patterns in gut microbiome prevalence and abundance are similar across host species, then we would expect that increasing prevalence thresholds would yield similar changes to alpha diversity and beta dissimilarity scores across host species datasets. We analyzed eight gut microbiome datasets based on 16S rRNA gene amplicon sequencing and collected from different host species to (1) compare macroecological patterns across datasets, including amplicon sequence variant (ASV) detection rate with sequencing depth and sample size, occupancy-abundance curves, and rank-abundance curves; (2) test whether increasing prevalence thresholds generate universal or host-species specific effects on alpha and beta diversity scores; and (3) test whether diversity scores from prevalence-filtered core communities correlate with unfiltered data. We found that gut microbiomes collected from diverse hosts demonstrated similar ASV detection rates with sequencing depth, yet required different sample sizes to sufficiently capture rare ASVs across the host population. This suggests that sample size rather than sequencing depth tends to limit the ability of studies to detect rare ASVs across the host population. Despite differences in the distribution and detection of rare ASVs, microbiomes exhibited similar occupancy-abundance and rank-abundance curves. Consequently, increasing prevalence thresholds generated remarkably similar trends in standardized alpha diversity and beta dissimilarity across species datasets until high thresholds above 70%. At this point, diversity scores tended to become unpredictable for some diversity measures. Moreover, high prevalence thresholds tended to generate diversity scores that correlated poorly with the original unfiltered data. Overall, we recommend that high prevalence thresholds over 70% are avoided, and promote the use of diversity measures that account for phylogeny and abundance (Balance-weighted phylogenetic diversity and Weighted Unifrac for alpha and beta diversity, respectively), because we show that these measures are insensitive to prevalence filtering and therefore allow for the consistent comparison of core gut microbiomes across studies without the need for prevalence filtering.

• Xin, Zong; Wang, Tiejun; Skidmore, Andrew & Heurich, Marco Dietmar (2021). Estimating fine-scale visibility in a temperate forest landscape using airborne laser scanning. International Journal of Applied Earth Observation and Geoinformation. ISSN 1569-8432. 103. doi: 10.1016/j.jag.2021.102478. Full text in Research Archive Show summary

  Visibility is a key factor influencing animal behavior in forest ecosystems. Fine-scale visibility in forested areas has been measured by ground-based approaches at the plot level, using site-specific methods that have limited spatial coverage. Here we examine airborne laser scanning (ALS) as a novel tool to quantify fine-scale visibility in the temperate forests of Germany at a landscape scale. We validate the (vertically-derived) ALS-derived visibility measures using proven (horizontally-derived) terrestrial laser scanning (TLS) estimates of true visibility. Our results indicate that there is a good agreement between the visibility resulting from ALS and TLS with an R2 ranging from 0.53 to 0.84 and a normalized RMSE varying from 15.92% to 11.81% at various plot sizes, with the highest accuracy achieved using a plot size of 35 × 35 m. Our study demonstrates for the first time that ALS can be successfully applied to quantify fine-scale visibility in temperate forests at a landscape level. This approach holds potential for studying the spatial behavior of animals (e.g., habitat selection and predator–prey relationships) in forest ecosystems.

• Hoerman, Christian von; Lackner, Tomas; Sommer, David; Heurich, Marco Dietmar; Benbow, M. Eric & Müller, Jörg (2021). Carcasses at Fixed Locations Host a Higher Diversity of Necrophilous Beetles. Insects. 12(5). doi: 10.3390/insects12050412. Full text in Research Archive Show summary

  Whereas vertebrate scavengers have a higher diversity reported at randomly placed carcasses, the drivers of insect diversity on carrion, such as the exposure type (fixed versus random) or the carrion species, are still incompletely understood. We analyzed beetle diversity at differently exposed carcasses in the low-range mountain forest of the Bavarian Forest National Park in Germany. We tested if scavenging beetles, similarly to vertebrate scavengers, show a higher diversity at randomly placed carcasses compared to easily manageable fixed places. Ninety-two beetle species at 29 exposed wildlife carcasses (roe, red deer, and red foxes) were detected. Beetle diversity was higher at fixed locations possessing extended highly nutrient-rich cadaver decomposition islands as important refuges for threatened red-listed species, such as Necrobia violacea (Coleoptera: Cleridae). Particularly noticeable in our insect traps were the following two rare species, the “primitive” carrion beetle Necrophilus subterraneus (Coleoptera: Agyrtidae) and the false clown beetle Sphaerites glabratus (Coleoptera: Sphaeritidae). In Europe, only the species S. glabratus out of the genus Sphaerites is present. This emphasizes the importance of carrion for biodiversity conservation. We clearly show the relevance of leaving and additional providing wildlife carcasses in a dedicated place in protected forests for preserving very rare and threatened beetle species as essential members of the decomposing community.

• Palmero, Stefano; Belotti, Elisa; Bufka, Ludek; Gahbauer, Martin; Heibl, Christoph & Premier, Joe [Show all 8 contributors for this article] (2021). Demography of a Eurasian lynx (Lynx lynx) population within a strictly protected area in Central Europe. Scientific Reports. 11. doi: 10.1038/s41598-021-99337-2. Full text in Research Archive Show summary

  Large carnivores promote crucial ecosystem processes but are increasingly threatened by human persecution and habitat destruction. Successful conservation of this guild requires information on long-term population dynamics obtained through demographic surveys. We used camera traps to monitor Eurasian lynx between 2009 and 2018 in a strictly protected area in the Bohemian Forest Ecosystem, located in the core of the distribution of the Bohemian–Bavarian–Austrian lynx population. Thereby, we estimated sex-specific demographic parameters using spatial capture–recapture (SCR) models. Over 48,677 trap nights, we detected 65 unique lynx individuals. Density increased from 0.69 to 1.33 and from 1.09 to 2.35 individuals/100 km2 for open and closed population SCR models, respectively, with corresponding positive population growth rates (mean = 1.06). Estimated yearly sex-specific survival probabilities for the entire monitoring period were high (females 82%, males 90%) and per capita recruitment rate was low (females 12%, males 9%), indicating a low yearly population turnover. We ascertained an average number of recruits of 1.97 and a generation time of 2.64 years when considering resident reproducing females. We confirmed that reproduction in the study area took place successfully every year. Despite the overall increase in local lynx densities, the number of detected family groups remained constant throughout the study period. These results indicated that the strictly protected study area acts as a source for the multi-use landscapes in its surroundings. In this first open population SCR study on lynx, we provide sex-specific demographic parameters that are fundamental information for lynx management in the study area as well as in similar contexts Europe-wide.

• Latifi, Hooman; Holzwarth, Stefanie; Skidmore, Andrew; Bruna, Josef; Cervenka, Jaroslav & Darvishzadeh, Roshanak [Show all 15 contributors for this article] (2021). A laboratory for conceiving Essential Biodiversity Variables (EBVs)—The ‘Data pool initiative for the Bohemian Forest Ecosystem’. Methods in Ecology and Evolution. doi: 10.1111/2041-210X.13695. Full text in Research Archive Show summary

  Effects of climate change-induced events on forest ecosystem dynamics of composition, function and structure call for increased long-term, interdisciplinary and integrated research on biodiversity indicators, in particular within strictly protected areas with extensive non-intervention zones. The long-established concept of forest supersites generally relies on long-term funds from national agencies and goes beyond the logistic and financial capabilities of state-or region-wide protected area administrations, universities and research institutes. We introduce the concept of data pools as a smaller-scale, user-driven and reasonable alternative to co-develop remote sensing and forest ecosystem science to validated products, biodiversity indicators and management plans. We demonstrate this concept with the Bohemian Forest Ecosystem Data Pool, which has been established as an interdisciplinary, international data pool within the strictly protected Bavarian Forest and Šumava National Parks and currently comprises 10 active partners. We demonstrate how the structure and impact of the data pool differs from comparable cases. We assessed the international influence and visibility of the data pool with the help of a systematic literature search and a brief analysis of the results. Results primarily suggest an increase in the impact and visibility of published material during the life span of the data pool, with highest visibilities achieved by research conducted on leaf traits, vegetation phenology and 3D-based forest inventory. We conclude that the data pool results in an efficient contribution to the concept of global biodiversity observatory by evolving towards a training platform, functioning as a pool of data and algorithms, directly communicating with management for implementation and providing test fields for feasibility studies on earth observation missions.

• Shi, Yifang; Wang, Tiejun; Skidmore, Andrew; Hotzwarth, Stefanie; Heiden, Uta & Heurich, Marco Dietmar (2021). Mapping individual silver fir trees using hyperspectral and LiDAR data in a Central European mixed forest. International Journal of Applied Earth Observation and Geoinformation. ISSN 1569-8432. 98. doi: 10.1016/j.jag.2021.102311. Full text in Research Archive Show summary

  Mapping a specific tree species at individual tree level across landscapes using remote sensing is challenging, especially in forests where co-occurring tree species exhibit similar characteristics. In Central European mixed forests, silver fir and Norway spruce have been identified as a pair of coniferous tree species with similar spectral and structural characteristics, typically leading to a major misclassification error in mapping studies. Here, we aimed to accurately map individual silver fir trees in a spruce-dominated natural forest in the Bavarian Forest National Park using integrated airborne hyperspectral and LiDAR data. To accomplish this goal, we extracted a set of relevant spectral and structural features from the hyperspectral and LiDAR data and used them to build machine learning classification models. Specifically, we compared the performance of three one-class classification algorithms (i.e. one-class support vector machine, biased support vector machine, and maximum entropy) for mapping individual silver fir trees. Our results showed that the biased support vector machine classifier yielded the highest mapping accuracy, with the area under the curve for positive and unlabeled samples (puAUC) achieving 0.95 (kappa 0.90). We found that the intensity value of 95th percentile of normalized tree height and the percentage of first returns above 2 m high were the most influential structural features, capturing the main morphological difference between silver fir and Norway spruce at the top tree crown. We also found that the wavebands at 700.1 nm, 714.5 nm, and 1201.6 nm were the most robust spectral bands, which are strongly affected by chlorophyll and foliar water content. Our study suggests that discovering links between spectral and structural features captured by different remotely sensed data and species-specific traits can significantly improve the mapping accuracy of a focal species at the individual tree level.

• Janik, Tomas; Peters, Wibke; Salek, Martin; Romportl, Dusan; Jirku, Miloslav & Engleder, Thomas [Show all 9 contributors for this article] (2021). The declining occurrence of moose (Alces alces) at the southernmost edge of its range raise conservation concerns. Ecology and Evolution. 11(10), p. 5468–5483. doi: 10.1002/ece3.7441. Full text in Research Archive Show summary

  The border region between Austria, the Czech Republic, and Germany harbors the most south-western occurrence of moose in continental Europe. The population originated in Poland, where moose survived, immigrated from former Soviet Union or were reintroduced after the Second World War expanded west- and southwards. In recent years, the distribution of the nonetheless small Central European population seems to have declined, necessitating an evaluation of its current status. In this study, existing datasets of moose observations from 1958 to 2019 collected in the three countries were combined to create a database totaling 771 records (observations and deaths). The database was then used to analyze the following: (a) changes in moose distribution, (b) the most important mortality factors, and (c) the availability of suitable habitat as determined using a maximum entropy approach. The results showed a progressive increase in the number of moose observations after 1958, with peaks in the 1990s and around 2010, followed by a relatively steep drop after 2013. Mortality within the moose population was mostly due to human interactions, including 13 deadly wildlife-vehicle collisions, particularly on minor roads, and four animals that were either legally culled or poached. Our habitat model suggested that higher altitudes (ca. 700–1,000 m a.s.l.), especially those offering wetlands, broad-leaved forests and natural grasslands, are the preferred habitats of moose whereas steep slopes and areas of human activity are avoided. The habitat model also revealed the availability of large core areas of suitable habitat beyond the current distribution, suggesting that habitat was not the limiting factor explaining the moose distribution in the study area. Our findings call for immediate transboundary conservation measures to sustain the moose population, such as those aimed at preventing wildlife-vehicle collisions and illegal killings. Infrastructure planning and development activities must take into account the habitat requirements of moose.

• Bödeker, Kai; Ammer, Christian; Knoke, Thomas & Heurich, Marco Dietmar (2021). Determining Statistically Robust Changes in Ungulate Browsing Pressure as a Basis for Adaptive Wildlife Management. Forests. 12(8). doi: 10.3390/f12081030. Full text in Research Archive Show summary

  Ungulate browsing has a major impact on the composition and structure of forests. Repeatedly conducted, large-scale regeneration inventories can monitor the extent of browsing pressure and its impacts on forest regeneration development. Based on the respective results, the necessity and extent of wildlife management activities such as hunting, fencing, etc., can be identified at a landscape scale. However, such inventories have rarely been integrated into wildlife management decision making. In this article, we evaluate a regeneration inventory method which was carried out in the Bavarian Forest National Park between 2007 and 2018. We predict the browsing impact by calculating browsing probabilities using a logistic mixed effect model. To provide wildlife managers with feedback on their activities, we developed a test which can assess significant changes in browsing probability between different inventory periods. To find the minimum observable browsing probability change, we simulated ungulate browsing based on the data of a potential browsing indicator species (Sorbus aucuparia) in the National Park. Sorbus aucuparia is evenly distributed, commonly found, selectively browsed and meets the ecosystem development objectives in our study area. We were able to verify a browsing probability change down to ±5 percentage points with a sample size of about 1,000 observations per inventory run. In view of the size of the National Park and the annual fluctuations in browsing pressure, this estimation accuracy seems sufficient. In seeking the maximal cost-efficiency, we were able to reduce this sample size in a sensitivity analysis by about two thirds without severe loss of information for wildlife management. Based on our findings, the presented inventory method combined with our evaluation tool has the potential to be a robust and efficient instrument to assess the impact of herbivores that are in the National Park and other regions.

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• Cagnacci, Francesca; Linnell, John Durrus; Heurich, Marco Dietmar; Flagstad, Øystein; Elmhagen, Bodil & Hogg, Carolyn [Show all 7 contributors for this article] (2025). Managing the Wild? Exploring the Role of Wildlife Management in Rewilding. Full text in Research Archive
• Oliveira, Teresa; Carricondo-Sanchez, David; Mattisson, Jenny; Voigt, Kristina; Corradini, Andrea & Linnell, John Durrus [Show all 10 contributors for this article] (2022). Predicting kill sites from an apex predator(Lynx lynx) in different multi-prey systems. Full text in Research Archive
• Kauffman, Matthew J.; Cagnacci, Francesca; Chamaillé-Jammes, Simon; Hebblewhite, Mark; Hopcraft, J. Grant C. & Merkle, Jerod A. [Show all 54 contributors for this article] (2021). Mapping out a future for ungulate migrations. Limited mapping of migrations hampers conservation. Science. ISSN 0036-8075. 372(6542), p. 566–569. doi: 10.1126/science.abf0998. Full text in Research Archive Show summary

  Migration of ungulates (hooved mammals) is a fundamental ecological process that promotes abundant herds, whose effects cascade up and down terrestrial food webs. Migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity (fig. S1). When ungulates move in large aggregations, their hooves, feces, and urine create conditions that facilitate distinct biotic communities. The migrations of ungulates have sustained humans for thousands of years, forming tight cultural links among Indigenous people and local communities. Yet ungulate migrations are disappearing at an alarming rate (1). Efforts by wildlife managers and conservationists are thwarted by a singular challenge: Most ungulate migrations have never been mapped in sufficient detail to guide effective conservation. Without a strategic and collaborative effort, many of the world’s great migrations will continue to be truncated, severed, or lost in the coming decades. Fortunately, a combination of animal tracking datasets, historical records, and local and Indigenous knowledge can form the basis for a global atlas of migrations, designed to support conservation action and policy at local, national, and international levels.

• Carpentier, Cecile Agnes Edith; Linnell, John Durrus; Heurich, Marco Dietmar & Gimenez, Olivier (2026). Modelling prey dynamics in multi-predator systems: European roe deer (Capreolus capreolus) persistence under predation by Eurasian lynx (Lynx lynx) and hunting in northern landscapes. Universitet i Innlandet / University of Inland Norway. ISSN 9788283806342. Full text in Research Archive Show summary

  With the return of large carnivores to human-dominated landscapes, both humans and wild prey must adapt to this new environment, which brings increased predation pressure on prey and new conflicts between humans and carnivores. For wild ungulates, the combined effects of predation and human harvest can increase their vulnerability to population declines or even local extinction. This dissertation explores the drivers of roe deer persistence in a multi-predator Scandinavian system using complementary modelling approaches. The first two chapters investigate the effects of biotic and abiotic factors on roe deer populations, using two modelling approaches. Chapter I focuses on the cumulative effects of predation, hunting, and stochastic climatic events, while also exploring, in a relatively general and theoretical framework, the role of immigration and landscape refuges on roe deer population persistence using a matrix population model. This chapter emphasises the importance of additive mortality sources and highlights the existence of underlying mechanisms that enable the deer population to persist. Chapter II focuses in more detail on how spatial heterogeneity in mortality risk at the individual level influences population dynamics using a spatial individual-based model, highlighting the importance of refuges, movement, and spatial variation in risk in a multi-predator context. The final two chapters investigate the role of human harvest in predator-prey systems. Chapter III discusses the relevance of a century-old principle for modern wildlife management, particularly in mitigating human-carnivore conflicts. Chapter IV evaluates different harvest strategies in the lynx-roe deer system using a coupled predator-prey matrix model. The results show that even relatively simple heuristic strategies that adaptively harvest both predator and prey to changing population densities improve the stability and persistence of both populations compared to non-adaptive approaches. Combining complementary modelling approaches, this dissertation provides key insights into the mechanisms underlying predator-prey dynamics and highlights the importance of integrating predation, harvest, and spatial processes for the sustainable management of wildlife in human-dominated landscapes.

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