13 research outputs found

    Estimating Amur tiger (\u3ci\u3ePanthera tigris altaica\u3c/i\u3e) kill rates and potential consumption rates using global positioning system collars

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    The International Union for Conservation of Nature has classified all subspecies of tigers (Panthera tigris) as endangered and prey depletion is recognized as a primary driver of declines. Prey depletion may be particularly important for Amur tigers (P. t. altaica) in the Russian Far East, living at the northern limits of their range and with the lowest prey densities of any tiger population. Unfortunately, rigorous investigations of annual prey requirements for any tiger population are lacking. We deployed global positioning system (GPS) collars on Amur tigers during 2009–2012 to study annual kill rates in the Russian Far East. We investigated 380 GPS location clusters and detected 111 kill sites. We then used logistic regression to model both the probability of a kill site at location clusters and the size of prey species at kill sites according to several spatial and temporal cluster covariates. Our top model for predicting kill sites included the duration of the cluster in hours and cluster fidelity components as covariates (overall classification success 86.3%; receiver operating characteristic score of 0.894). Application of the model to all tiger GPS data revealed that Amur tigers in this study made a kill once every 6.5 days (95% confidence interval [95% CI] 5.9–7.2 days) and consumed an estimated average of 8.9 kg of prey biomass per day (95% CI 8.8–9.0 kg/day). The success of efforts to reverse tiger declines will be at least partially determined by wildlife managers’ ability to conserve large ungulates at adequate densities for recovering tiger populations

    Space Use by Brown Bears (Ursus arctos) in the Sikhote-Alin

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    Грамотное управление популяцией бурого медведя (Ursus arctos L.) требует знания его экологии, в том числе использования животными пространства. Данный вопрос на Дальнем Востоке России изучен недостаточно из-за небольшого количества программ, применяющих телеметрические методы исследования бурых медведей. Целью работы являлось изучение особенностей использования пространства бурыми медведями на Сихотэ-Алине. В 1993– 2002 гг. на Среднем Сихотэ-Алине с помощью радиотелеметрии вели наблюдения за восемью взрослыми и одним молодым самцами, пятью взрослыми и одной молодой самками, оснащенными ошейниками с УКВ-радиопередатчиками. У взрослых особей средний размер годовых участков обитания, полученный с помощью метода «фиксированный кернел», был больше у самцов (891,34 ± 346,99 км2) по сравнению с самками (349,94 ± 543,06 км2). Молодые животные в течение года занимали участки площадью 237,24 и 333,64 км2 у самца и самки соответственно. Максимальный размер имел двухлетний участок самца (9217,36 км2). Размер ядерных зон участков обитания варьировал в широких пределах (6,12–358,45 км2). Структура и географическое расположение участков обитания и их ядерных зон зависели от сезонного выбора медведями местообитаний, распределения, обилия и доступности кормов. Между собой перекрывались участки обитания как самцов с самками, так и особей одного пола. Полученные результаты важны для управления популяцией бурого медведя на Сихотэ-АлинеProper management of brown bear populations (Ursus arctos) requires knowledge of their ecology, including space use. Brown bear spatial patterns are particularly poorly understood in the Russian Far East, due to lack of telemetry studies. The aim of this work was to study space use by brown bears in the Sikhote-Alin region. From 1993 to 2002, we used VHF radiocollars to collect spatial data from nine males (eight adults and one juvenile) and six females (five adults and one juvenile) in the Middle Sikhote-Alin. Fixed Kernel home range size estimates were larger for males (891.34 ± 346.99 km2) than for females (349.94 ± 543.06 km2). The juvenile home range sizes were 237.24 and 333.64 km2 for the male and female, respectively. The maximum home range size was for the two-year area of one male (9217.36 km2). The core area sizes varied over a wide range (6.12–358.45 km2). The structure and location of home ranges and their core areas depended upon the seasonal habitat selection of bears, as well as the distribution, abundance, and accessibility of foraging resources. Bears’ home ranges overlapped between males and females, as well as between same sex individuals. The results of this work are important for the management of the brown bear population in the Sikhote-Ali

    Distemper, extinction, and vaccination of the Amur tiger

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    Canine distemper virus (CDV) has recently emerged as an extinction threat for the endangered Amur tiger (Panthera tigris altaica). CDV is vaccine-preventable, and control strategies could require vaccination of domestic dogs and/or wildlife populations. However, vaccination of endangered wildlife remains controversial, which has led to a focus on interventions in domestic dogs, often assumed to be the source of infection. Effective decision making requires an understanding of the true reservoir dynamics, which poses substantial challenges in remote areas with diverse host communities. We carried out serological, demographic, and phylogenetic studies of dog and wildlife populations in the Russian Far East to show that a number of wildlife species are more important than dogs, both in maintaining CDV and as sources of infection for tigers. Critically, therefore, because CDV circulates among multiple wildlife sources, dog vaccination alone would not be effective at protecting tigers. We show, however, that low-coverage vaccination of tigers themselves is feasible and would produce substantive reductions in extinction risks. Vaccination of endangered wildlife provides a valuable component of conservation strategies for endangered species

    Coat Polymorphism in Eurasian Lynx: Adaptation to Environment or Phylogeographic Legacy?

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    We studied the relationship between the variability and contemporary distribution of pelage phenotypes in one of most widely distributed felid species and an array of environmental and demographic conditions. We collected 672 photographic georeferenced records of the Eurasian lynx throughout Eurasia. We assigned each lynx coat to one of five phenotypes. Then we fitted the coat patterns to different environmental and anthropogenic variables, as well as the effective geographic distances from inferred glacial refugia. A majority of lynx were either of the large spotted (41.5%) or unspotted (uniform, 36.2%) phenotype. The remaining patterns (rosettes, small spots and pseudo-rosettes) were represented in 11.0%, 7.4%, and 3.9% of samples, respectively. Although various environmental variables greatly affected lynx distribution and habitat suitability, it was the effect of least-cost distances from locations of the inferred refugia during the Last Glacial Maximum that explained the distribution of lynx coat patterns the best. Whereas the occurrence of lynx phenotypes with large spots was explained by the proximity to refugia located in the Caucasus/Middle East, the uniform phenotype was associated with refugia in the Far East and Central Asia. Despite the widely accepted hypothesis of adaptive functionality of coat patterns in mammals and exceptionally high phenotypic polymorphism in Eurasian lynx, we did not find well-defined signs of habitat matching in the coat pattern of this species. Instead, we showed how the global patterns of morphological variability in this large mammal and its environmental adaptations may have been shaped by past climatic change.publishedVersio

    Canine distemper virus as a threat to wild tigers in Russia and across their range

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    Canine distemper virus (CDV) has recently been identified in populations of wild tigers in Russia and India. Tiger populations are generally too small to maintain CDV for long periods, but are at risk of infections arising from more abundant susceptible hosts that constitute a reservoir of infection. Because CDV is an additive mortality factor, it could represent a significant threat to small, isolated tiger populations. In Russia, CDV was associated with the deaths of tigers in 2004 and 2010, and was coincident with a localized decline of tigers in Sikhote-Alin Biosphere Zapovednik (from 25 tigers in 2008 to 9 in 2012). Habitat continuity with surrounding areas likely played an important role in promoting an ongoing recovery. We recommend steps be taken to assess the presence and the impact of CDV in all tiger range states, but should not detract focus away from the primary threats to tigers, which include habitat loss and fragmentation, poaching and retaliatory killing. Research priorities include: (i) recognition and diagnosis of clinical cases of CDV in tigers when they occur; and (ii) collection of baseline data on the health of wild tigers. CDV infection of individual tigers need not imply a conservation threat, and modeling should complement disease surveillance and targeted research to assess the potential impact to tiger populations across the range of ecosystems, population densities and climate extremes occupied by tigers. Describing the role of domestic and wild carnivores as contributors to a local CDV reservoir is an important precursor to considering control measures

    Coat polymorphism in eurasian lynx: Adaptation to environment or phylogeographic legacy?

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    WOS:000716261800001We studied the relationship between the variability and contemporary distribution of pelage phenotypes in one of most widely distributed felid species and an array of environmental and demographic conditions. We collected 672 photographic georeferenced records of the Eurasian lynx throughout Eurasia. We assigned each lynx coat to one of five phenotypes. Then we fitted the coat patterns to different environmental and anthropogenic variables, as well as the effective geographic distances from inferred glacial refugia. A majority of lynx were either of the large spotted (41.5%) or unspotted (uniform, 36.2%) phenotype. The remaining patterns (rosettes, small spots and pseudo-rosettes) were represented in 11.0%, 7.4%, and 3.9% of samples, respectively. Although various environmental variables greatly affected lynx distribution and habitat suitability, it was the effect of least-cost distances from locations of the inferred refugia during the Last Glacial Maximum that explained the distribution of lynx coat patterns the best. Whereas the occurrence of lynx phenotypes with large spots was explained by the proximity to refugia located in the Caucasus/Middle East, the uniform phenotype was associated with refugia in the Far East and Central Asia. Despite the widely accepted hypothesis of adaptive functionality of coat patterns in mammals and exceptionally high phenotypic polymorphism in Eurasian lynx, we did not find well-defined signs of habitat matching in the coat pattern of this species. Instead, we showed how the global patterns of morphological variability in this large mammal and its environmental adaptations may have been shaped by past climatic change

    Introduced, Mixed, and Peripheral: Conservation of Mitochondrial-DNA Lineages in the Wild Boar (<i>Sus scrofa</i> L.) Population in the Urals

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    Translocations and introductions are important events that allow organisms to overcome natural barriers. The genetic background of colonization success and genetic consequences of the establishment of populations in new environments are of great interest for predicting species’ colonization success. The wild boar has been introduced into many parts of the world. We analyzed sequences of the mitochondrial-DNA control region in the wild boars introduced into the Ural region and compared them with sequences from founder populations (from Europe, the Caucasus, Central Asia, and the Far East). We found that the introduced population has high genetic diversity. Haplotypes from all the major phylogenetic clades were detected in the analyzed group of the animals from the Urals. In this group, no haplotypes identical to Far Eastern sequences were detectable despite a large number of founders from that region. The contribution of lineages originating from Eastern Europe was greater than expected from the proportions (%) of European and Asian animals in the founder populations. This is the first study on the genetic diversity and structure of a wild boar population of mixed origin at the northern periphery of this species’ geographical range

    Range-wide whole-genome resequencing of the brown bear reveals drivers of intraspecies divergence

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    Population-genomic studies can shed new light on the effect of past demographic processes on contemporary population structure. We reassessed phylogeographical patterns of a classic model species of postglacial recolonisation, the brown bear ( ), using a range-wide resequencing dataset of 128 nuclear genomes. In sharp contrast to the erratic geographical distribution of mtDNA and Y-chromosomal haplotypes, autosomal and X-chromosomal multi-locus datasets indicate that brown bear population structure is largely explained by recent population connectivity. Multispecies coalescent based analyses reveal cases where mtDNA haplotype sharing between distant populations, such as between Iberian and southern Scandinavian bears, likely results from incomplete lineage sorting, not from ancestral population structure (i.e., postglacial recolonisation). However, we also argue, using forward-in-time simulations, that gene flow and recombination can rapidly erase genomic evidence of former population structure (such as an ancestral population in Beringia), while this signal is retained by Y-chromosomal and mtDNA, albeit likely distorted. We further suggest that if gene flow is male-mediated, the information loss proceeds faster in autosomes than in X chromosomes. Our findings emphasise that contemporary autosomal genetic structure may reflect recent population dynamics rather than postglacial recolonisation routes, which could contribute to mtDNA and Y-chromosomal discordances

    Coat Polymorphism in Eurasian Lynx: Adaptation to Environment or Phylogeographic Legacy?

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    We studied the relationship between the variability and contemporary distribution of pelage phenotypes in one of most widely distributed felid species and an array of environmental and demographic conditions. We collected 672 photographic georeferenced records of the Eurasian lynx throughout Eurasia. We assigned each lynx coat to one of five phenotypes. Then we fitted the coat patterns to different environmental and anthropogenic variables, as well as the effective geographic distances from inferred glacial refugia. A majority of lynx were either of the large spotted (41.5%) or unspotted (uniform, 36.2%) phenotype. The remaining patterns (rosettes, small spots and pseudo-rosettes) were represented in 11.0%, 7.4%, and 3.9% of samples, respectively. Although various environmental variables greatly affected lynx distribution and habitat suitability, it was the effect of least-cost distances from locations of the inferred refugia during the Last Glacial Maximum that explained the distribution of lynx coat patterns the best. Whereas the occurrence of lynx phenotypes with large spots was explained by the proximity to refugia located in the Caucasus/Middle East, the uniform phenotype was associated with refugia in the Far East and Central Asia. Despite the widely accepted hypothesis of adaptive functionality of coat patterns in mammals and exceptionally high phenotypic polymorphism in Eurasian lynx, we did not find well-defined signs of habitat matching in the coat pattern of this species. Instead, we showed how the global patterns of morphological variability in this large mammal and its environmental adaptations may have been shaped by past climatic change
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