25 research outputs found

    Population dynamics of the common shrew (Sorex araneus) in Central European forest clearings

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    The population dynamics of shrews (Soricidae) are not well known even though they form an important part of forest ecosystems and represent suitable bioindicators of ecosystem quality. The aim of this study was to evaluate the population dynamics of shrews in mountain and upland forest clearings in four study areas within the Czech Republic and to reveal how climatic factors influenced fluctuations in their abundance for a decade (2007-2017). In total, we trapped 7,538 individuals of 18 small mammal species. From 760 individuals of seven shrew species, the common shrew (Sorex araneus) was significantly dominated in all study areas. We did not observe any significant, regular multi-annual cycles of the common shrew. However, a cross-correlation in density fluctuation of this species was detected in all mountain areas indicating the influence of environmental factors acting on a larger geographical scale. The autumn abundance of shrews was dependent on the subset of climatic variables, together explaining 56% of the variance in the linear regression model. Except for the length of the snow cover of GREATER-THAN OR EQUAL TO 5 cm, all other significant variables were associated with North Atlantic Oscillation (NAO). Longer duration of snow cover during the winter before trapping, higher average NAO value during months before trapping, and NAO value in September influenced negatively the autumn abundance of shrews, contrary, higher value of NAO in May and October increased the abundance. Our results demonstrate the sensitivity of shrews to winters with a longer period of snow cover and to climatic oscillations associated with the NAO, whose effect is monthly dependent and probably indirectly influencing shrews through their prey.OA-hybri

    Multi-seasonal systematic camera-trapping reveals fluctuating densities and high turnover rates of Carpathian lynx on the western edge of its native range

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    Camera-trapping and capture-recapture models are the most widely used tools for estimating densities of wild felids that have unique coat patterns, such as Eurasian lynx. However, studies dealing with this species are predominantly on a short-term basis and our knowledge of temporal trends and population persistence is still scarce. By using systematic camera-trapping and spatial capture-recapture models, we estimated lynx densities and evaluated density fluctuations, apparent survival, transition rate and individual's turnover during five consecutive seasons at three different sites situated in the Czech-Slovak-Polish borderland at the periphery of the Western Carpathians. Our density estimates vary between 0.26 and 1.85 lynx/100 km2 suitable habitat and represent the lowest and the highest lynx densities reported from the Carpathians. We recorded 1.5-4.1-fold changes in asynchronous fluctuated densities among all study sites and seasons. Furthermore, we detected high individual's turnover (on average 46.3 +- 8.06% in all independent lynx and 37.6 +- 4.22% in adults) as well as low persistence of adults (only 3 out of 29 individuals detected in all seasons). The overall apparent survival rate was 0.63 +- 0.055 and overall transition rate between sites was 0.03 +- 0.019. Transition rate of males was significantly higher than in females, suggesting male-biased dispersal and female philopatry. Fluctuating densities and high turnover rates, in combination with documented lynx mortality, indicate that the population in our region faces several human-induced mortalities, such as poaching or lynx-vehicle collisions. These factors might restrict population growth and limit the dispersion of lynx to other subsequent areas, thus undermining the favourable conservation status of the Carpathian population. Moreover, our study demonstrates that long-term camera-trapping surveys are needed for evaluation of population trends and for reliable estimates of demographic parameters of wild territorial felids, and can be further used for establishing successful management and conservation measures.Postprin

    Long-term genetic monitoring of a reintroduced Eurasian lynx population does not indicate an ongoing loss of genetic diversity

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    Where reintroduced wildlife populations are considered as vulnerable this is generally due to limited founder size and isolation. While many of these populations show low levels of genetic diversity, little is known about the temporal patterns of genetic diversity loss and the role of initial founder effects vs. ongoing genetic drift. Here we analysed genotype data from 582 Eurasian lynx samples from the reintroduced Bohemian-Bavarian-Austrian population (BBA) over a time span of 35 years, representing approximately 13 generations. Two-wave reintroduction of lynx from at least two distinct West-Carpathian areas resulted in relatively high start-up of genetic diversity. After the initial decline when the population lost about a quarter of its genetic diversity compared to the Carpathian source population, the genetic diversity and effective population size remained almost unchanged over the next 20 years. Despite confirmed isolation of BBA and thus absence of gene flow, we detected relatively low inbreeding during the two recent decades within the slightly increasing population size, which may have prevented ongoing loss of genetic diversity. Given the current status of BBA, we do not support genetic reinforcement to maintain its long-term viability; but urge the importance of facilitating gene flow with neighbouring lynx populations through an improvement of landscape connectivity and by strengthening law enforcement as well as the prevention of illegal killings. A sound genetic monitoring alongside regular camera trap-based monitoring of population size, health status and reproduction is pivotal to decide on future conservation interventions.publishedVersio

    Human disturbance is the most limiting factor driving habitat selection of a large carnivore throughout Continental Europe

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    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.acceptedVersio

    Prerequisites for coexistence: human pressure and refuge habitat availability shape continental‑scale habitat use patterns of a large carnivore

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    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 modifcation. 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 modifcation 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-modifed 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-modifed areas during periods of high exposure (daytime) or high vulnerability (postnatal period) to human pressure. Conclusions Our fndings 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.publishedVersio

    Integrating animal tracking datasets at a continental scale for mapping Eurasian lynx habitat

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    Aim: The increasing availability of animal tracking datasets collected across many sites provides new opportunities to move beyond local assessments to enable de-tailed 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 recolo-nizing 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 habi-tat 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 habi-tat models. Our habitat maps identified large areas of suitable, but currently unoccu-pied 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.publishedVersio

    A common statement on anthropogenic hybridization of the European wildcat (Felis silvestris)

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    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

    Monitoring of large carnivores in SCI Beskydy: final report

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    The aim of the project was to evaluate the status of large carnivores' populations (European lynx, wolf, and brown bear) in SCI Beskydy using different monitoring methods

    Application of genetic methods for the detection of deer origin and existence of interspecific hybridization

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    Hybridization between native red deer and non-native sika deer is a real threat in the Czech Republic, even though its existence has been questioned for a long time. The main cause of hybrids’ non-acceptance has been the fact that no reliable methods of their detection exist until recently. However, the application of modern molecular-genetic methods, mainly the analyses of microsatellite loci polymorphism, helps us to detect the proportion of hybrid individuals in wild populations and to establish necessary management measures for their elimination. Most importantly, the usage of molecular-genetic methods enables to detect hybrid individuals of next generations that bear no visible phenotypic signs of previous hybridisation

    Data from: Admixture of eastern and western European red deer lineages as a result of postglacial re-colonisation of the Czech Republic (Central Europe)

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    Due to a restriction of the distributional range of European red deer (Cervus elaphus L.) during the Quaternary and subsequent recolonization of Europe from different refugia, a clear phylogeographical pattern in genetic structure has been revealed using mitochondrial DNA markers. In Central Europe, 2 distinct, eastern and western, lineages of European red deer are present; however, admixture between them has not yet been studied in detail. We used mitochondrial DNA (control region and cytochrome b gene) sequences and 22 microsatellite loci from 522 individuals to investigate the genetic diversity of red deer in what might be expected to be an intermediate zone. We discovered a high number of unique mtDNA haplotypes belonging to each lineage and high levels of genetic diversity (cyt b H = 0.867, D-loop H = 0.914). The same structuring of red deer populations was also revealed by microsatellite analysis, with results from both analyses thus suggesting a suture zone between the 2 lineages. Despite the fact that postglacial recolonization of Central Europe by red deer occurred more than 10000 years ago, the degree of admixture between the 2 lineages is relatively small, with only 10.8% admixed individuals detected. Direct translocations of animals by humans have slightly blurred the pattern in this region; however, this blurring was more apparent when using maternally inherited markers than nuclear markers
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