205 research outputs found

    Recent history, current status, conservation and management of native mammalian carnivore species in Great Britain

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record After historical declines in population sizes and ranges, we compare and contrast the recent history and contemporary variation in the status of Great Britain's eight native mammalian carnivore species from the 1960s to 2017. Wildcat Felis silvestris conservation status is unfavourable and is masked by hybridisation with domestic cats Felis catus. Red foxes Vulpes vulpes remain widespread but are currently declining. European otter Lutra lutra, European pine marten Martes martes and European polecat Mustela putorius populations are characterised by rapid recovery. Otters have almost completely recolonised Great Britain, polecats have expanded their range throughout southern Britain from refugia in Wales and pine martens have expanded their range from the Scottish Highlands. European badgers Meles meles have generally increased in population density. Status assessments of stoats Mustela erminea and weasels Mustela nivalis are data-deficient but available evidence suggests that stoats may have increased while weasels may have declined. Anthropogenic processes influencing carnivore status include legal protections, habitat quality, reintroductions, predator control, pollutants, hybridisation and diseases and their associated control practices. Population effects of contaminants, such as anticoagulant rodenticides, remain poorly characterised. The widespread interface with domestic and feral cats makes the wildcat's situation precarious. Recent declines in rabbit Oryctolagus cuniculus populations are a concern, given that several carnivore species depend on them as food. We conclude that, with the exception of the wildcat, the status of Great Britain's mammalian carnivores has markedly improved since the 1960s. Better understanding of the social aspects of interactions between humans and expanding predator populations is needed if conflict is to be avoided and long-term co-existence with people is to be possible.Vincent Wildlife TrustUniversity of Exete

    Diets of European polecat Mustela putorius in Great Britain during fifty years of population recovery

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    This is the final version. Available from Springer via the DOI in this record. Following nineteenth-century declines, polecats Mustela putorius are recolonising Great Britain. Polecat diet relates to two potential risks to recovery. First, rabbits Oryctolagus cuniculus, which are important prey for polecats, have experienced extreme population fluctuations, with near extirpation due to myxomatosis in the 1950s, recovery in 1960s–1990s and declines in 1990s–2010s. Second, polecats are secondarily exposed to anticoagulant rodenticides by eating contaminated rodents, and the frequency of polecat exposure to rodenticides is increasing. We analysed stomach contents from 99 polecats collected in 2012–2016 and compared results with earlier studies. Lagomorphs were the most abundant prey (66% frequency of occurrence, 95% confidence interval 53–74%), followed by other mammals (12%, 4–18%), amphibians (10%, 3–16%) and birds (7%, 1–13%). Diet varied seasonally; lagomorph occurrence was highest in spring and summer and lowest in autumn. Dietary niche breadth was greater in the 1960s, when rabbits were scarce, than in other decades, but did not differ between the 1990s and 2010s, indicating that diets have not diversified with recent rabbit declines. This may be because rabbit abundance is not yet low enough to cause dietary diversification or because polecats were collected in areas where rabbits were still abundant. Rodents did not increase in diet between the 1990s and 2010s and still occur with < 10% frequency, indicating that rodents need not contribute much to diet to expose polecats to rodenticides. This potentially limits the effectiveness of management actions designed to minimise polecat exposure to contaminated rodent prey.Vincent Wildlife TrustUniversity of Exete

    Yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) as zoomonitors of environmental contamination at a polluted area in Slovakia

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    <p>Abstract</p> <p>Background</p> <p>Free-living wild rodents are often used as zoomonitors of environmental contamination. In the present study, accumulation of cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in critical organs of yellow-necked mice (<it>Apodemus flavicollis</it>) and bank voles (<it>Myodes glareolus</it>) trapped in a polluted area in Nováky, Slovakia was investigated.</p> <p>Methods</p> <p>Yellow-necked mice (n = 8) and bank voles (n = 10) were collected using standard theriological methods for wood ecosystems. All animals were adult males in good physical condition. The concentrations of Cd, Cu, Fe, and Zn in the liver, kidney, and bone were determined by atomic absorption spectrophotometry.</p> <p>Results</p> <p>The highest concentrations of Cd and Zn were found in the bone of both species while Cu and Fe accumulated mainly in kidney or liver. Significant higher concentrations of Cd and Cu were detected in the liver of bank voles than in yellow-necked mice. Similar significant higher levels of Cd and Zn were found in the bone of bank voles. In contrast, significant higher concentrations of Cu and Fe were present in the kidney of yellow-necked mice.</p> <p>Conclusions</p> <p>In the yellow-necked mouse and bank vole, bone seems to accumulate Cd and Zn following prolonged exposure. On the contrary, kidney and liver store Cu and Fe after a long-term environmental exposure. In the present study, bank voles seemed to be more heavy metal loaded zoomonitors than yellow-necked mice.</p

    Poisoning of reintroduced red kites (Milvus Milvus) in England

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    Programmes to reintroduce predatory birds are resource intensive and expensive, yet there are few long-term studies on the health of these reintroduced birds following release. A total of 326 red kites (Milvus milvus) were released at four sites in England between 1989 and 2006 as part of efforts to reintroduce this species to England and Scotland, resulting in the establishment of several rapidly expanding populations in the wild. Detailed post-mortem examinations were carried out on 162 individuals found dead between 1989 and 2007, involving both released and wild-fledged birds. Toxicological analysis of one or more compounds was performed on 110 of the 162 birds. Poisoning was diagnosed in 32 of these 110 kites, 19 from second generation anticoagulant rodenticides, 9 from other pesticides and six from lead. Criteria for diagnosing anticoagulant rodenticide poisoning included visible haemorrhage on gross post-mortem examination and levels of anticoagulant rodenticide exceeding 100 ng/g, but levels were elevated above 100 ng/g in a further eight red kites without visible haemorrhages, suggesting poisoning may have occurred in more birds. The anticoagulant rodenticides difenacoum and bromadiolone were the most common vertebrate control agents involved during this period. Poisoning of red kites may be slowing their rate of population recovery and range expansion in England. Simple modifications of human activity, such as best practice in rodent control campaigns, tackling the illegal use of pesticides and the use of non-toxic alternatives to lead ammunition, can reduce our impact on red kites and probably other populations of predatory and scavenging species

    Assessing the exposure risk and impacts of pharmaceuticals in the environment on individuals and ecosystems.

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    The use of human and veterinary pharmaceuticals is increasing. Over the past decade, there has been a proliferation of research into potential environmental impacts of pharmaceuticals in the environment. A Royal Society-supported seminar brought together experts from diverse scientific fields to discuss the risks posed by pharmaceuticals to wildlife. Recent analytical advances have revealed that pharmaceuticals are entering habitats via water, sewage, manure and animal carcases, and dispersing through food chains. Pharmaceuticals are designed to alter physiology at low doses and so can be particularly potent contaminants. The near extinction of Asian vultures following exposure to diclofenac is the key example where exposure to a pharmaceutical caused a population-level impact on non-target wildlife. However, more subtle changes to behaviour and physiology are rarely studied and poorly understood. Grand challenges for the future include developing more realistic exposure assessments for wildlife, assessing the impacts of mixtures of pharmaceuticals in combination with other environmental stressors and estimating the risks from pharmaceutical manufacturing and usage in developing countries. We concluded that an integration of diverse approaches is required to predict 'unexpected' risks; specifically, ecologically relevant, often long-term and non-lethal, consequences of pharmaceuticals in the environment for wildlife and ecosystems

    Cancer risks following diagnostic and therapeutic radiation exposure in children

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    The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life

    Sampling and contaminant monitoring protocol for raptors

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    In May 2013 representatives from six countries gathered in Murcia, Spain, to attend the Workshop on &ldquo;Setting best practices on raptor contaminant monitoring activities in Europe&rdquo; funded by EURAPMON. The workshop developed a rough draft of the current protocol. The protocol was subsequently completed with the involvement of investigators from Belgium, Denmark, France, Germany, The Netherlands, Norway, Spain, Sweden and the United Kingdom. All contributors are experts in monitoring contaminants in raptors. The aim of this sampling protocol is to provide guidance on types of best practice that will facilitate harmonisation of procedures between existing and emerging schemes and so maximise the reliability, comparability and interoperability of data.The methods here do not require use of anaesthesia on birds. This protocol covers the sampling of blood and feathers from live birds, addled and deserted eggs, internal organs and tissues from dead specimens, and other samples such as faeces, preen oil and pellets.</p

    Poisoning of reintroduced red kites (Milvus milvus) in England

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    Programmes to reintroduce predatory birds are resource intensive and expensive, yet there are few long-term studies on the health of these reintroduced birds following release. A total of 326 red kites (Milvus milvus) were released at four sites in England between 1989 and 2006 as part of efforts to reintroduce this species to England and Scotland, resulting in the establishment of several rapidly expanding populations in the wild. Detailed post-mortem examinations were carried out on 162 individuals found dead between 1989 and 2007, involving both released and wild-fledged birds. Toxicological analysis of one or more compounds was performed on 110 of the 162 birds. Poisoning was diagnosed in 32 of these 110 kites, 19 from second-generation anticoagulant rodenticides, 9 from other pesticides and 6 from lead. Criteria for diagnosing anticoagulant rodenticide poisoning included visible haemorrhage on gross post-mortem examination and levels of anticoagulant rodenticide exceeding 100 ng/g, but levels were elevated above 100 ng/g in a further eight red kites without visible haemorrhages, suggesting poisoning may have occurred in more birds. The anticoagulant rodenticides difenacoum and bromadiolone were the most common vertebrate control agents involved during this period. Poisoning of red kites may be slowing their rate of population recovery and range expansion in England. Simple modifications of human activity, such as best practice in rodent control campaigns, tackling the illegal use of pesticides and the use of non-toxic alternatives to lead ammunition, can reduce our impact on red kites and probably other populations of predatory and scavenging species

    Vascular responses of the extremities to transdermal application of vasoactive agents in Caucasian and African descent individuals

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    This is an accepted manuscript of an article published by Springer in European Journal of Applied Physiology on 04/04/2015, available online: https://doi.org/10.1007/s00421-015-3164-2 The accepted version of the publication may differ from the final published version.© 2015, Springer-Verlag Berlin Heidelberg. Purpose: Individuals of African descent (AFD) are more susceptible to non-freezing cold injury than Caucasians (CAU) which may be due, in part, to differences in the control of skin blood flow. We investigated the skin blood flow responses to transdermal application of vasoactive agents. Methods: Twenty-four young males (12 CAU and 12 AFD) undertook three tests in which iontophoresis was used to apply acetylcholine (ACh 1 w/v %), sodium nitroprusside (SNP 0.01 w/v %) and noradrenaline (NA 0.5 mM) to the skin. The skin sites tested were: volar forearm, non-glabrous finger and toe, and glabrous finger (pad) and toe (pad). Results: In response to SNP on the forearm, AFD had less vasodilatation for a given current application than CAU (P = 0.027–0.004). ACh evoked less vasodilatation in AFD for a given application current in the non-glabrous finger and toe compared with CAU (P = 0.043–0.014) with a lower maximum vasodilatation in the non-glabrous finger (median [interquartile], AFD n = 11, 41[234] %, CAU n = 12, 351[451] %, P = 0.011) and non-glabrous toe (median [interquartile], AFD n = 9, 116[318] %, CAU n = 12, 484[720] %, P = 0.018). ACh and SNP did not elicit vasodilatation in the glabrous skin sites of either group. There were no ethnic differences in response to NA. Conclusion: AFD have an attenuated endothelium-dependent vasodilatation in non-glabrous sites of the fingers and toes compared with CAU. This may contribute to lower skin temperature following cold exposure and the increased risk of cold injuries experienced by AFD.Published versio

    Leptogenesis from loop effects in curved spacetime

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    We describe a new mechanism -- radiatively-induced gravitational leptogenesis -- for generating the matter-antimatter asymmetry of the Universe. We show how quantum loop effects in C and CP violating theories cause matter and antimatter to propagate differently in the presence of gravity, and prove this is forbidden in flat space by CPT and translation symmetry. This generates a curvature-dependent chemical potential for leptons, allowing a matter-antimatter asymmetry to be generated in thermal equilibrium in the early Universe. The time-dependent dynamics necessary for leptogenesis is provided by the interaction of the virtual self-energy cloud of the leptons with the expanding curved spacetime background, which violates the strong equivalence principle and allows a distinction between matter and antimatter. We show here how this mechanism is realised in a particular BSM theory, the see-saw model, where the quantum loops involve the heavy sterile neutrinos responsible for light neutrino masses. We demonstrate by explicit computation of the relevant two-loop Feynman diagrams how the size of the radiative corrections relevant for leptogenesis becomes enhanced by increasing the mass hierarchy of the sterile neutrinos, and show that for realistic phenomenological parameters this mechanism can generate the observed baryon-to-photon ratio of the Universe
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