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Jon E Swenson - One of the best experts on this subject based on the ideXlab platform.
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diet of the Brown Bear in himalaya combining classical and molecular genetic techniques
PLOS ONE, 2019Co-Authors: Muhammad Nawaz, Christian Miquel, Alice Valentini, Noor Khan, Pierre Taberlet, Jon E SwensonAbstract:The ecological requirements of Brown Bears are poorly known in the Himalaya region, which complicates conservation efforts. We documented the diet of the Himalayan Brown Bear (Ursus arctos isabellinus) by combining classical scat analysis and a newly developed molecular genetic technique (the trnL approach), in Deosai National Park, Pakistan. Brown Bears consumed over 50 plant species, invertebrates, ungulates, and several rodents. Eight plant families; Poaceae, Polygonaceae, Cyperaceae, Apiaceae, Asteraceae, Caryophyllaceae, Lamiaceae, and Rubiaceae were commonly eaten with graminoids comprising the bulk of the diet. Golden marmots comprised the major mammalian biomass in the park, and were also the main meat source for Bears. Animal matter, making 36% of dietary content, contributed half of the digestible energy, due to its higher nutritious value. We did not find a significant temporal pattern in diet, perhaps because the availability of the major diet (graminoids) did not change over the foraging period. Male Brown Bears were more carnivorous than females, probably because of their larger size, which requires higher energy and also makes them more efficient in capturing marmots. Frequencies of three plant species were also significantly higher in male Brown Bears; Bistorta affinis, Carex diluta, and Carex sp. Diet of the Brown Bear differed significantly between the park and surrounding valleys. In valleys, diet consisted predominantly of graminoids and crops, whereas the park provided more nutritious and diverse foodThe estimated digestible energy available to Brown Bears in Deosai was the lowest documented among Brown Bear populations, due to the lack of fruits and a relatively lower meat content. The low nutritious diet and high cost of metabolism in a high-altitude environment, probably explains the very low reproductive potential of this population.
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humans and climate change drove the holocene decline of the Brown Bear
Scientific Reports, 2017Co-Authors: Jorg Albrecht, Jon E Swenson, Nuria Selva, Kamil A Barton, Robert S Sommer, Richard BischofAbstract:The current debate about megafaunal extinctions during the Quaternary focuses on the extent to which they were driven by humans, climate change, or both. These two factors may have interacted in a complex and unexpected manner, leaving the exact pathways to prehistoric extinctions unresolved. Here we quantify, with unprecedented detail, the contribution of humans and climate change to the Holocene decline of the largest living terrestrial carnivore, the Brown Bear (Ursus arctos), on a continental scale. We inform a spatially explicit metapopulation model for the species by combining life-history data and an extensive archaeofaunal record from excavations across Europe with reconstructed climate and land-use data reaching back 12,000 years. The model reveals that, despite the broad climatic niche of the Brown Bear, increasing winter temperatures contributed substantially to its Holocene decline - both directly by reducing the species' reproductive rate and indirectly by facilitating human land use. The first local extinctions occurred during the Mid-Holocene warming period, but the rise of the Roman Empire 2,000 years ago marked the onset of large-scale extinctions, followed by increasingly rapid range loss and fragmentation. These findings strongly support the hypothesis that complex interactions between climate and humans may have accelerated megafaunal extinctions.
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challenges of managing a european Brown Bear population lessons from sweden 1943 2013
Wildlife Biology, 2017Co-Authors: Jon E Swenson, Andreas Zedrosser, Michael Schneider, Arne Soderberg, Robert Franzen, Jonas KindbergAbstract:‘Adaptive management’, which has been defined as the repeated iteration between management action, scientific assessment and revised management action, leading to a strengthened foundation for management, is required by Swedish law to be incorporated into the management of large carnivores. We have evaluated whether the size and/or trend of the Brown Bear Ursus arctos population in Sweden corresponded to management-decided national objectives during five management regimes during the past 70 years (1943—2013). We found that the objective had been met in only one period, when it had been worded very vaguely. During the last period studied (2008—2013), when management was carried out on the county level and adaptive management was required by the Swedish Government, four of six counties met their trend objectives, but only one of six met the population objectives, although one was close to meeting them. Sociological studies have documented major problems in communication among the members of the county dele...
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drivers of hibernation in the Brown Bear
Frontiers in Zoology, 2016Co-Authors: Alina L Evans, Navinder J Singh, Andrea Friebe, Jon M Arnemo, Timothy G Laske, Ole Frobert, Jon E SwensonAbstract:Hibernation has been a key area of research for several decades, essentially in small mammals in the laboratory, yet we know very little about what triggers or ends it in the wild. Do climatic factors, an internal biological clock, or physiological processes dominate? Using state-of-the-art tracking and monitoring technology on fourteen free-ranging Brown Bears over three winters, we recorded movement, heart rate (HR), heart rate variability (HRV), body temperature (Tb), physical activity, ambient temperature (TA), and snow depth to identify the drivers of the start and end of hibernation. We used behavioral change point analyses to estimate the start and end of hibernation and convergent cross mapping to identify the causal interactions between the ecological and physiological variables over time. To our knowledge, we have built the first chronology of both ecological and physiological events from before the start to the end of hibernation in the field. Activity, HR, and Tb started to drop slowly several weeks before den entry. Bears entered the den when snow arrived and when ambient temperature reached 0 °C. HRV, taken as a proxy of sympathetic nervous system activity, dropped dramatically once the Bear entered the den. This indirectly suggests that denning is tightly coupled to metabolic suppression. During arousal, the unexpected early rise in Tb (two months before den exit) was driven by TA, but was independent of HRV. The difference between Tb and TA decreased gradually suggesting that Bears were not thermoconforming. HRV increased only three weeks before exit, indicating that late activation of the sympathetic nervous system likely finalized restoration of euthermic metabolism. Interestingly, it was not until TA reached the presumed lower critical temperature, likely indicating that the Bears were seeking thermoneutrality, that they exited the den. We conclude that Brown Bear hibernation was initiated primarily by environmental cues, but terminated by physiological cues.
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consequences of a demographic bottleneck on genetic structure and variation in the scandinavian Brown Bear
Molecular Ecology, 2015Co-Authors: Jon E Swenson, Georgios Xenikoudakis, Erik Ersmark, Jeanluc Tison, Lisette P Waits, Jonas Kindberg, Love DalenAbstract:The Scandinavian Brown Bear went through a major decline in population size approximately 100 years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian Brown Bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian Brown Bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution.
Javier Naves - One of the best experts on this subject based on the ideXlab platform.
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Brown Bear attacks on humans a worldwide perspective
Scientific Reports, 2019Co-Authors: Giulia Bombieri, Nuria Selva, Javier Naves, Alberto Fernandezgil, T Bespalova, Vincenzo Penteriani, Jose Vicente Lopezbao, Huseyin Ambarli, Carlos Bautista, V BobrovAbstract:The increasing trend of large carnivore attacks on humans not only raises human safety concerns but may also undermine large carnivore conservation efforts. Although rare, attacks by Brown Bears Ursus arctos are also on the rise and, although several studies have addressed this issue at local scales, information is lacking on a worldwide scale. Here, we investigated Brown Bear attacks (n = 664) on humans between 2000 and 2015 across most of the range inhabited by the species: North America (n = 183), Europe (n = 291), and East (n = 190). When the attacks occurred, half of the people were engaged in leisure activities and the main scenario was an encounter with a female with cubs. Attacks have increased significantly over time and were more frequent at high Bear and low human population densities. There was no significant difference in the number of attacks between continents or between countries with different hunting practices. Understanding global patterns of Bear attacks can help reduce dangerous encounters and, consequently, is crucial for informing wildlife managers and the public about appropriate measures to reduce this kind of conflicts in Bear country.
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patterns of Brown Bear damages on apiaries and management recommendations in the cantabrian mountains spain
PLOS ONE, 2018Co-Authors: Javier Naves, Alberto Fernandezgil, Eloy Revilla, Maria Del Mar Delgado, Vincenzo Penteriani, Jose Vicente Lopezbao, Andres Ordiz, Miguel DelibesAbstract:This work received support from Agencia Estatal de Investigacion from the Ministry of Economy, Industry and Competitiveness, Spain. Project CGL2017-83045-R AEI/FEDER EU, Dr Eloy Revilla; Agencia Estatal de Investigacio´n from the Ministry of Economy, Industry and Competitiveness, Spain. Project CGL2017-82782-P AEI/FEDER EU, Dr Vincenzo Penteriani; Regional Government of Asturias. 2007-2010 Project: Demographic evolution of the Brown Bear population, identification of corridors of communication between subpopulations and analysis of the damages caused by the species to agriculture and livestock in Asturias Ref. Pres. PA 2007:, 18.07-443F-610.000, Dr Miguel Delibes; Ramon & Cajal research contract, Agencia Estatal de Investigacio´n from the Ministry of Economy, Industry and Competitiveness, Spain. RYC-2014- 16263, Dr Mari´a del Mar Delgado; Ramon & Cajal research contract, Agencia Estatal de Investigacion from the Ministry of Economy, Industry and Competitiveness, Spain. RYC-2015-18932; project CGL2017-87528-R AEI/FEDER EU, Dr Jose Vicente Lopez-Bao.
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estimating the population size of the endangered cantabrian Brown Bear through genetic sampling
Wildlife Biology, 2014Co-Authors: Trinidad Perez, Javier Naves, Alberto Fernandezgil, Miguel Delibes, Jose Fernando Vazquez, Juan Seijas, Jesus Albornoz, Eloy Revilla, Ana DominguezAbstract:The Cantabrian Brown Bear Ursus arctos population can be seen as a paradigm in conservation biology due to its endangerment status and genetic uniqueness. Therefore, the need to obtain basic demographic data to inform management actions for conservation is imperative. Despite this, empirical data on the size and trends of the Cantabrian Bear population are scarce. Here we present the first estimates of population size (Nc) and effective population size (Ne) of the whole Cantabrian Brown Bear population. We genotyped 270 non-invasive samples collected during 2006 throughout the entire range of the population and subsequently identified 130 individuals. Different model estimators of Nc based on capture—markrecapture (CMR) procedures were compared. The average for the best three models (Mh Chao, Mh Darroch and CAPWIRE TIRM) yielded a total estimate of Nc = 223 individuals (CI95% = 183–278) and Ne 50 (CI95% = 36–75) providing an Ne / Nc ratio of 0.22. Estimates for the two subpopulations commonly recognized i...
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Brown Bear habitat suitability in the pyrenees transferability across sites and linking scales to make the most of scarce data
Journal of Applied Ecology, 2012Co-Authors: Jodie Martin, Pierreyves Quenette, Javier Naves, Eloy Revilla, Dominique Allaine, Jon E SwensonAbstract:Summary 1. Identification of suitable habitats for small, endangered populations is important to preserve key areas for potential augmentation. However, replicated spatial data from a sufficient number of individuals are often unavailable for such populations, leading to unreliable habitat models. This is the case for the endangered Pyrenean Brown Bear Ursus arctos population, with only about 20 individuals surviving in two isolated groups. 2. We conducted habitat suitability analyses at two spatial scales (coarse and local). Given the limited available data, we used information from the nearby Cantabrian Brown Bear population in Spain to develop a two-dimensional model (human and natural variables) at a coarse scale, based on logistic regression, which we applied in the Pyrenees. At a local scale, we used Bear presence in the Pyrenees to describe the population’s ecological niche and develop a habitat suitability model using presence-only methods. We combined these models to obtain a more integrative understanding of Bear requirements. 3. The coarse-scale model showed a good transferability to the Pyrenees, identifying preference for areas with high forest connectivity, masting trees, rugged terrain and shrubs and avoidance of areas with anthropogenic structures. The local-scale model was consistent with the coarse-scale model. Bears showed a trade-off between food resources (scarcer at high elevations) and human presence (higher at low elevations). 4. Our models illustrated that there is unoccupied good habitat for Bears in the Pyrenees that could host new individuals. Combining two scales allowed us to identify areas that should be prioritized for management actions and also those that should be easier to manage for Bears. 5. Synthesis and applications. Our study illustrates how a nested-scale approach, combining coarse data from a different population and fine-scale local data, can aid in the management of small populations with limited data. This was applied to remnant Brown Bear populations to identify priorities for conservation management.
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evidence for improved connectivity between cantabrian Brown Bear subpopulations
Ursus, 2010Co-Authors: Trinidad Perez, Javier Naves, Jose Fernando Vazquez, Juan Seijas, Jesus Albornoz, Ana Corao, Ana DominguezAbstract:Abstract The Brown Bear (Ursus arctos) population in the Cantabrian Mountains of northwest Spain is among the most endangered Bear populations worldwide. It is divided into 2 isolated and genetically differentiated subpopulations. We present evidence of recent male migration between the subpopulations based on genetic identification of hair and scats samples gathered between 2004 and 2007. Of 76 identified individuals, our analysis assigned 3 males sampled in the eastern subpopulation to the western subpopulation. As well, 1 male genetically belonging to the eastern subpopulation was repeatedly sampled along his way to the western subpopulation during April to November 2006 (a linear distance of 144 km). This Bear's path may help identify natural corridors, which could be improved through restoration management. In addition, we identified 2 genetically admixed individuals during 2008 in the Western limit of the eastern subpopulation range. Connectivity between subpopulations and gene flow appears to be im...
Pierre Taberlet - One of the best experts on this subject based on the ideXlab platform.
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diet of the Brown Bear in himalaya combining classical and molecular genetic techniques
PLOS ONE, 2019Co-Authors: Muhammad Nawaz, Christian Miquel, Alice Valentini, Noor Khan, Pierre Taberlet, Jon E SwensonAbstract:The ecological requirements of Brown Bears are poorly known in the Himalaya region, which complicates conservation efforts. We documented the diet of the Himalayan Brown Bear (Ursus arctos isabellinus) by combining classical scat analysis and a newly developed molecular genetic technique (the trnL approach), in Deosai National Park, Pakistan. Brown Bears consumed over 50 plant species, invertebrates, ungulates, and several rodents. Eight plant families; Poaceae, Polygonaceae, Cyperaceae, Apiaceae, Asteraceae, Caryophyllaceae, Lamiaceae, and Rubiaceae were commonly eaten with graminoids comprising the bulk of the diet. Golden marmots comprised the major mammalian biomass in the park, and were also the main meat source for Bears. Animal matter, making 36% of dietary content, contributed half of the digestible energy, due to its higher nutritious value. We did not find a significant temporal pattern in diet, perhaps because the availability of the major diet (graminoids) did not change over the foraging period. Male Brown Bears were more carnivorous than females, probably because of their larger size, which requires higher energy and also makes them more efficient in capturing marmots. Frequencies of three plant species were also significantly higher in male Brown Bears; Bistorta affinis, Carex diluta, and Carex sp. Diet of the Brown Bear differed significantly between the park and surrounding valleys. In valleys, diet consisted predominantly of graminoids and crops, whereas the park provided more nutritious and diverse foodThe estimated digestible energy available to Brown Bears in Deosai was the lowest documented among Brown Bear populations, due to the lack of fruits and a relatively lower meat content. The low nutritious diet and high cost of metabolism in a high-altitude environment, probably explains the very low reproductive potential of this population.
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evolution of major histocompatibility complex class i and class ii genes in the Brown Bear
BMC Evolutionary Biology, 2012Co-Authors: Katarzyna Kuduk, Jon E Swenson, Katarzyna Bojarska, Pierre Taberlet, Jonas Kindberg, Wieslaw Babik, Ewa B śliwinska, Jacek RadwanAbstract:Major histocompatibility complex (MHC) proteins constitute an essential component of the vertebrate immune response, and are coded by the most polymorphic of the vertebrate genes. Here, we investigated sequence variation and evolution of MHC class I and class II DRB, DQA and DQB genes in the Brown Bear Ursus arctos to characterise the level of polymorphism, estimate the strength of positive selection acting on them, and assess the extent of gene orthology and trans-species polymorphism in Ursidae. We found 37 MHC class I, 16 MHC class II DRB, four DQB and two DQA alleles. We confirmed the expression of several loci: three MHC class I, two DRB, two DQB and one DQA. MHC class I also contained two clusters of non-expressed sequences. MHC class I and DRB allele frequencies differed between northern and southern populations of the Scandinavian Brown Bear. The rate of nonsynonymous substitutions (dN) exceeded the rate of synonymous substitutions (dS) at putative antigen binding sites of DRB and DQB loci and, marginally significantly, at MHC class I loci. Models of codon evolution supported positive selection at DRB and MHC class I loci. Both MHC class I and MHC class II sequences showed orthology to gene clusters found in the giant panda Ailuropoda melanoleuca. Historical positive selection has acted on MHC class I, class II DRB and DQB, but not on the DQA locus. The signal of historical positive selection on the DRB locus was particularly strong, which may be a general feature of caniforms. The presence of MHC class I pseudogenes may indicate faster gene turnover in this class through the birth-and-death process. South–north population structure at MHC loci probably reflects origin of the populations from separate glacial refugia.
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estimating population size and trends of the swedish Brown Bear ursus arctos population
Wildlife Biology, 2011Co-Authors: Jonas Kindberg, Jon E Swenson, Christian Miquel, Eva Bellemain, Goran Ericsson, Pierre TaberletAbstract:Abstract Estimating population size and trends are key issues in the conservation and management of large carnivores. The rebounding Brown Bear Ursus arctos population in Sweden is monitored by two different systems, both relying on voluntary resources. Population estimates have been calculated using Capture-Mark-Recapture methods, based on DNA-based scat surveys in five of the six Swedish counties with established Bear populations. A total of 1,358 genotypes were identified using DNA extracted from collected scats. An independent ongoing programme, the Large Carnivore Observation Index (LCOI), was initiated in 1998. The LCOI uses effort-corrected observations of Bears by moose Alces alces hunters during the moose hunt (> 2 million observation hours/year) and has shown a good correlation with relative population density of Bears using the DNA-based method. From this, we have calculated population trends during the period 1998-2007. Using an exponential model, we estimated the yearly increase in the Bear p...
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genetic tracking of the Brown Bear in northern pakistan and implications for conservation
Biological Conservation, 2007Co-Authors: Eva Bellemain, Jon E Swenson, Muhammad Nawaz, Alice Valentini, Pierre TaberletAbstract:Asian Bears face major threats due to the impact of human activities as well as a critical lack of knowledge about their status, distribution and needs for survival. Once abundant in northern Pakistan, the Himalayan Brown Bear (Ursus arctos isabellinus) has been exterminated in most of its former distribution range. It presently occurs sparsely, in small populations, the Deosai National Park supporting the largest isolate. This decline might imply a reduction in genetic diversity, compromising the survival of the population. Using a combination of fecal DNA analysis and field data, our study aimed at assessing the size and genetic status of the Deosai population and give guidelines for its conservation and management. Using fecal genetic analysis, we estimated the population to be 40‐50 Bears, which compares well with the field census of 38 Bears. The northern Pakistani Brown Bear population may have undergone an approximate 200‐300-fold decrease during the last thousand years, probably due to glaciations and the influence of growing human population. However, in spite of the presence of a bottleneck genetic signature, the Deosai population has a moderate level of genetic diversity and is not at immediate risk of inbreeding depression. Gene flow might exist with adjacent populations. We recommend careful monitoring of this population in the future both with field observations and genetic analyses, including sampling of adjacent populations to assess incoming gene flow. The connectivity with adjacent populations in Pakistan and India will be of prime importance for the longterm survival of Deosai Bears.
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an evaluation of field and non invasive genetic methods to estimate Brown Bear ursus arctos population size
Biological Conservation, 2006Co-Authors: Knut Hakon Solberg, Eva Bellemain, Pierre Taberlet, Olamattis Drageset, Jon E SwensonAbstract:Abstract Estimates of population size and density are essential for successful management and conservation of any species. Although there are a variety of methods available for estimating abundance and density of populations, most studies rely on only one estimator and very few studies have compared and critically evaluated the adequacy and the cost of these methods. We used the Brown Bear ( Ursus arctos ) in south-central Sweden to compare the performance of three different methods of estimating population size, including methods based on conventional field data as well as on non-invasive genetic data. The method based on observations of females with cubs underestimated the true population size, as the estimates were below the number of unique genotypes determined from faecal data inside the study area. The best traditional method was based on observations of Bears from a helicopter. The genetic method using the closed population MARK estimator, as recommended in a previous study, seemed to perform the best. We conclude that approximately 223 (188–282) Bears were present in our 7328 km 2 study area during 2001 and 2002 and suggest that this hunted Brown Bear population has been relatively stable for about ten years. The non-invasive genetic method was less expensive than the most reliable traditional field method (a CMR method based on observations of Bears from a helicopter), and preferable from an ethical point of view. We recommend that future studies using non-invasive genetic methods based on collected faecal samples should aim at collecting 2.5–3 times the number of faecal samples as the “assumed” number of animals.
Lisette P Waits - One of the best experts on this subject based on the ideXlab platform.
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consequences of a demographic bottleneck on genetic structure and variation in the scandinavian Brown Bear
Molecular Ecology, 2015Co-Authors: Jon E Swenson, Georgios Xenikoudakis, Erik Ersmark, Jeanluc Tison, Lisette P Waits, Jonas Kindberg, Love DalenAbstract:The Scandinavian Brown Bear went through a major decline in population size approximately 100 years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian Brown Bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian Brown Bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution.
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using a reference population yardstick to calibrate and compare genetic diversity reported in different studies an example from the Brown Bear
Heredity, 2012Co-Authors: Tomaž Skrbinsek, Lisette P Waits, Maja Jelencic, Hubert Potocnik, Ivan Kos, Peter TronteljAbstract:In species with large geographic ranges, genetic diversity of different populations may be well studied, but differences in loci and sample sizes can make the results of different studies difficult to compare. Yet, such comparisons are important for assessing the status of populations of conservation concern. We propose a simple approach of using a single well-studied reference population as a 'yardstick' to calibrate results of different studies to the same scale, enabling comparisons. We use a well-studied large carnivore, the Brown Bear (Ursus arctos), as a case study to demonstrate the approach. As a reference population, we genotyped 513 Brown Bears from Slovenia using 20 polymorphic microsatellite loci. We used this data set to calibrate and compare heterozygosity and allelic richness for 30 Brown Bear populations from 10 different studies across the global distribution of the species. The simplicity of the reference population approach makes it useful for other species, enabling comparisons of genetic diversity estimates between previously incompatible studies and improving our understanding of how genetic diversity is distributed throughout a species range.
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the power of genetic monitoring for studying demography ecology and genetics of a reintroduced Brown Bear population
Molecular Ecology, 2010Co-Authors: M De Barba, Lisette P Waits, Edward O Garton, Piero Genovesi, Ettore Randi, A Mustoni, Claudio GroffAbstract:Genetic monitoring has rarely been used for wildlife translocations despite the potential benefits this approach offers, compared to traditional field-based methods. We applied genetic monitoring to the reintroduced Brown Bear population in northern Italy. From 2002 to 2008, 2781 hair and faecal samples collected noninvasively plus 12 samples obtained from captured or dead Bears were used to follow the demographic and geographical expansion and changes in genetic composition. Individual genotypes were used to reconstruct the wild pedigree and revealed that the population increased rapidly, from nine founders to >27 individuals in 2008 (lambda=1.17-1.19). Spatial mapping of Bear samples indicated that most Bears were distributed in the region surrounding the translocation site; however, individual Bears were found up to 163 km away. Genetic diversity in the population was high, with expected heterozygosity of 0.74-0.79 and allelic richness of 4.55-5.41. However, multi-year genetic monitoring data showed that mortality rates were elevated, immigration did not occur, one dominant male sired all cubs born from 2002 to 2005, genetic diversity declined, relatedness increased, inbreeding occurred, and the effective population size was extremely small (Ne=3.03, ecological method). The comprehensive information collected through genetic monitoring is critical for implementing future conservation plans for the Brown Bear population in the Italian Alps. This study provides a model for other reintroduction programmes by demonstrating how genetic monitoring can be implemented to uncover aspects of the demography, ecology and genetics of small and reintroduced populations that will advance our understanding of the processes influencing their viability, evolution, and successful restoration.
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phylogeography and mitochondrial diversity of extirpated Brown Bear ursus arctos populations in the contiguous united states and mexico
Molecular Ecology, 2006Co-Authors: Craig R Miller, Lisette P Waits, Paul JoyceAbstract:The fossil record indicates that the Brown Bear (Ursus arctos) colonized North America from Asia over 50 000 years ago. The species historically occupied the western United States and northern Mexico but has been extirpated from over 99% of this range in the last two centuries. To evaluate colonization hypotheses, subspecific classifications, and historical patterns and levels of genetic diversity in this region, we sequenced 229 nucleotides of the mitochondrial DNA control region in 108 museum specimens. The work was set in a global context by synthesizing all previous Brown Bear control region sequences from around the world. In mid-latitude North America a single moderately diverse clade is observed, represented by 23 haplotypes with up to 3.5% divergence. Only eight of 23 haplotypes (35%) are observed in the extensively sampled extant populations suggesting a substantial loss of genetic variability. The restriction of all haplotypes from mid-latitude North America to a single clade suggests that this region was founded by Bears with a similar maternal ancestry. However, the levels and distributions of diversity also suggest that the colonizing population was not a small founder event, and that expansion occurred long enough ago for local mutations to accrue. Our data are consistent with recent genetic evidence that Brown Bears were south of the ice prior to the last glacial maximum. There is no support for previous subspecies designations, although Bears of the southwestern United States may have had a distinctive, but recent, pattern of ancestry.
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mitochondrial dna phylogeography of the north american Brown Bear and implications for conservation
Conservation Biology, 1998Co-Authors: Lisette P Waits, Sandra L Talbot, Ryk Ward, Gerald F ShieldsAbstract:The historical distribution of the Brown Bear (Ursus arctos) in North America included Alaska, western Canada, the western and midwestern states, plus northern Mexico. Currently, the Brown Bear is lim- ited to Alaska, the Canadian provinces of the Yukon, Northwest Territories, British Columbia, and Alberta, and six threatened subpopulations in the lower 48 states. To examine the evolutionary history of U. arctos in North America and to assess the genetic divergence between individuals from different geographic regions, we obtained 294 nucleotides of mitochondrial DNA sequence data from the control region for 317 free-rang- ing Brown Bears. Twenty-eight unique sequences, or mitochondrial DNA haplotypes were detected. The aver- age sequence divergence between haplotypes was high (43 %/), and some haplotypes differed by as many as 23 nucleotides. Phylogenetic analyses using maximum parsimony revealed four major mitochondrial DNA phy- logeographic groups, or clades. The significant phylogeographic structure detected in Brown Bears strongly contrasts with results obtainedfor other large carnivores and suggests limitedfemale-mediated gene flow. The mitochondrial DNA phylogeographic clades do not correlate with taxonomic classifications for U. arctos, and we hypothesize that the clades were formed prior to migration of this species into North America. We suggest evolutionarily significant units for conservation in three geographic regions: (1) the Alaskan islands of Admi- ralty, Baranof; and Chichagof; (2) mainland Alaska, Kodiak Island, and northern Canada; and (3) southern British Columbia, southern Alberta, and the states of Idaho, Montana, and Wyoming.
Jonas Kindberg - One of the best experts on this subject based on the ideXlab platform.
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challenges of managing a european Brown Bear population lessons from sweden 1943 2013
Wildlife Biology, 2017Co-Authors: Jon E Swenson, Andreas Zedrosser, Michael Schneider, Arne Soderberg, Robert Franzen, Jonas KindbergAbstract:‘Adaptive management’, which has been defined as the repeated iteration between management action, scientific assessment and revised management action, leading to a strengthened foundation for management, is required by Swedish law to be incorporated into the management of large carnivores. We have evaluated whether the size and/or trend of the Brown Bear Ursus arctos population in Sweden corresponded to management-decided national objectives during five management regimes during the past 70 years (1943—2013). We found that the objective had been met in only one period, when it had been worded very vaguely. During the last period studied (2008—2013), when management was carried out on the county level and adaptive management was required by the Swedish Government, four of six counties met their trend objectives, but only one of six met the population objectives, although one was close to meeting them. Sociological studies have documented major problems in communication among the members of the county dele...
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the gut microbiota modulates energy metabolism in the hibernating Brown Bear ursus arctos
Cell Reports, 2016Co-Authors: Jonas Kindberg, Jon M Arnemo, Felix Sommer, Marcus Stahlman, Olga Ilkayeva, Johan Josefsson, Christopher B Newgard, Ole FrobertAbstract:SUMMARY Hibernation is an adaptation that helps many animals to conserve energy during food shortage in winter. Brown Bears double their fat depots during summer and use these stored lipids during hibernation. Although Bears seasonally become obese, they remain metabolically healthy. We analyzed the microbiota of free-ranging Brown Bears during their active phase and hibernation. Compared to the active phase, hibernation microbiota had reduced diversity, reduced levels of Firmicutes and Actinobacteria, and increased levels of Bacteroidetes. Several metabolites involved in lipid metabolism, including triglycerides, cholesterol, and bile acids, were also affected by hibernation. Transplantation of the Bear microbiota from summer and winter to germ-free micetransferred some ofthe seasonal metabolicfeatures and demonstrated that the summer microbiota promoted adiposity without impairing glucose tolerance, suggesting that seasonal variation in the microbiota may contribute to host energy metabolism in the hibernating Brown Bear.
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consequences of a demographic bottleneck on genetic structure and variation in the scandinavian Brown Bear
Molecular Ecology, 2015Co-Authors: Jon E Swenson, Georgios Xenikoudakis, Erik Ersmark, Jeanluc Tison, Lisette P Waits, Jonas Kindberg, Love DalenAbstract:The Scandinavian Brown Bear went through a major decline in population size approximately 100 years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian Brown Bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian Brown Bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution.
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evolution of major histocompatibility complex class i and class ii genes in the Brown Bear
BMC Evolutionary Biology, 2012Co-Authors: Katarzyna Kuduk, Jon E Swenson, Katarzyna Bojarska, Pierre Taberlet, Jonas Kindberg, Wieslaw Babik, Ewa B śliwinska, Jacek RadwanAbstract:Major histocompatibility complex (MHC) proteins constitute an essential component of the vertebrate immune response, and are coded by the most polymorphic of the vertebrate genes. Here, we investigated sequence variation and evolution of MHC class I and class II DRB, DQA and DQB genes in the Brown Bear Ursus arctos to characterise the level of polymorphism, estimate the strength of positive selection acting on them, and assess the extent of gene orthology and trans-species polymorphism in Ursidae. We found 37 MHC class I, 16 MHC class II DRB, four DQB and two DQA alleles. We confirmed the expression of several loci: three MHC class I, two DRB, two DQB and one DQA. MHC class I also contained two clusters of non-expressed sequences. MHC class I and DRB allele frequencies differed between northern and southern populations of the Scandinavian Brown Bear. The rate of nonsynonymous substitutions (dN) exceeded the rate of synonymous substitutions (dS) at putative antigen binding sites of DRB and DQB loci and, marginally significantly, at MHC class I loci. Models of codon evolution supported positive selection at DRB and MHC class I loci. Both MHC class I and MHC class II sequences showed orthology to gene clusters found in the giant panda Ailuropoda melanoleuca. Historical positive selection has acted on MHC class I, class II DRB and DQB, but not on the DQA locus. The signal of historical positive selection on the DRB locus was particularly strong, which may be a general feature of caniforms. The presence of MHC class I pseudogenes may indicate faster gene turnover in this class through the birth-and-death process. South–north population structure at MHC loci probably reflects origin of the populations from separate glacial refugia.
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estimating population size and trends of the swedish Brown Bear ursus arctos population
Wildlife Biology, 2011Co-Authors: Jonas Kindberg, Jon E Swenson, Christian Miquel, Eva Bellemain, Goran Ericsson, Pierre TaberletAbstract:Abstract Estimating population size and trends are key issues in the conservation and management of large carnivores. The rebounding Brown Bear Ursus arctos population in Sweden is monitored by two different systems, both relying on voluntary resources. Population estimates have been calculated using Capture-Mark-Recapture methods, based on DNA-based scat surveys in five of the six Swedish counties with established Bear populations. A total of 1,358 genotypes were identified using DNA extracted from collected scats. An independent ongoing programme, the Large Carnivore Observation Index (LCOI), was initiated in 1998. The LCOI uses effort-corrected observations of Bears by moose Alces alces hunters during the moose hunt (> 2 million observation hours/year) and has shown a good correlation with relative population density of Bears using the DNA-based method. From this, we have calculated population trends during the period 1998-2007. Using an exponential model, we estimated the yearly increase in the Bear p...
