Home About us Contact
|
Home About us Contact | ||
|
|
||
Badgers
Kinds of Badgers Terms modified by Badgers Selected AbstractsAlcohol-Induced Disruption of Endocrine SignalingALCOHOLISM, Issue 8 2007Martin J. J. Ronis This article contains the proceedings of a symposium at the 2006 ISBRA Meeting in Sydney Australia, organized and cochaired by Martin J. Ronis and Thomas M. Badger. The presentations were (1) Effect of Long-Term Ethanol Consumption on Liver Injury and Repair, by Jack R. Wands; (2) Alcohol-Induced Insulin Resistance in Liver: Potential Roles in Regulation of ADH Expression, Ethanol Clearance, and Alcoholic Liver Disease, by Thomas M. Badger; (3) Chronic Gestational Exposure to Ethanol Causes Brain Insulin and Insulin-Like Growth Factor Resistance, by Suzanne M de la Monte; (4) Disruption of IGF-1 Signaling in Muscle: A Mechanism Underlying Alcoholic Myopathy, by Charles H. Lang; (5) The Role of Reduced Plasma Estradiol and Impaired Estrogen Signaling in Alcohol-Induced Bone Loss, by Martin J. Ronis; and (6) Short-Term Influence of Alcohol on Appetite-Regulating Hormones in Man, by Jan Calissendorff. [source] Alcohol Metabolism: Role in Toxicity and CarcinogenesisALCOHOLISM, Issue 2 2003Thomas M. Badger This article contains the proceedings of a symposium at the 2002 RSA Meeting in San Francisco, organized and co-chaired by Thomas M. Badger, Paul Shih-Jiun Yin, and Helmut Seitz. The presentations were (1) First-pass metabolism of ethanol: Basic and clinical aspects, by Charles Lieber; (2) Intracellular CYP2E1 transport, oxidative stress, cytokine release, and ALD, by Magnus Ingelman-Sundberg; (3) Pulsatile ethanol metabolism in intragastric infusion models: Potential role in toxic outcomes, by Thomas M. Badger and Martin J.J. Ronis; (4) Free radicals, adducts, and autoantibodies resulting from ethanol metabolism: Role in ethanol-associated toxicity, by Emanuele Albano; and (5) Gastrointestinal metabolism of ethanol and its possible role in carcinogenesis, by Helmut Seitz. [source] The role of the Badger (Meles meles) in rabies epizootiology and the implications for Great BritainMAMMAL REVIEW, Issue 1 2002G. C. Smith ABSTRACT The occurrence of a wildlife rabies epizootic in Britain remains a very unlikely event, but it is important to examine all the possible consequences of such an event. Here, I examine the possible role of the European Badger (Meles meles) in such an epizootic. The population density of Badgers in Britain is much higher than that in Europe, and appears to have increased substantially over the last decade or so. The population parameters and epizootiology of rabies in the Badger are reviewed in comparison with the Fox (Vulpes vulpes) and other species. Mustelids appear to be very susceptible to rabies, with the smaller mustelids becoming aggressive, although Badgers do not appear to show heightened aggression when infected. Badger populations on the continent become severely reduced when rabies arrives in the area, and circumstantial evidence strongly suggests that Badgers can easily transmit the virus. Preliminary models support the idea that the Badger could be a very significant secondary host, especially in the initial rabies outbreak. The population recovery rate of the Badger suggests that it is unlikely to become a primary host, although short-term epizootics in the Badger population are likely. The potential for controlling rabies in the Badger is also examined. [source] Spatial pattern of adult trees and the mammal-generated seed rain in the Iberian pearECOGRAPHY, Issue 3 2010Jose M. Fedriani The degree to which plant individuals are aggregated or dispersed co-determines how a species uses resources, how it is used as a resource, and how it reproduces. Quantifying such spatial patterns, however, presents several methodological issues that can be overcome by using spatial point pattern analyses (SPPA). We used SPPA to assess the distribution of P. bourgaeana adult trees and their seeds (within fecal samples) dispersed by three mammals (badger, fox, and wild boar) within a 72-ha plot across a range of spatial scales. Pyrus bourgaeana trees in our study plot (n=75) were clearly aggregated with a critical spatial scale of ca 25,m, and approximately nine randomly distributed tree clusters were identified. As expected from their marking behaviors, the spatial patterns of fecal deposition varied widely among mammal species. Whereas badger feces and dispersed seeds were clearly clustered at small spatial scales (<10,m), boar and fox feces were relatively scattered across the plot. A toroidal shift null model testing for independence indicated that boars tended to deliver seeds to the vicinity of adult trees and thus could contribute to the maintenance and enlargement of existing tree clusters. Badgers delivered feces and seeds in a highly clumped pattern but unlike boars, away from P. bourgaeana neighborhoods; thus, they are more likely to create new tree clusters than boars. The strong tree aggregation is likely to be the result of one or several non-exclusive processes, such as the spatial patterning of seed delivery by dispersers and seedling establishment beneath mother trees. In turn, the distinctive distribution of P. bourgaeana in Doñana appeared to interact with the foraging behavior of its mammalian seed dispersers, leading to neighbourhood-specific dispersal patterns and fruit-removal rates. Our study exemplifies how a detailed description of patterns generates testable hypotheses concerning the ecology of zoochorous. Pyrus bourgaeana dispersers were unique and complementary in their spatial patterning of seed delivery, which likely confers resilience to their overall service and suggests lack of redundancy and expendability of any one species. [source] Spatial organization, group living and ecological correlates in low-density populations of Eurasian badgers, Meles melesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2002Eloy Revilla Summary 1,Territoriality and group living are described in a low-density population of Eurasian badgers, Meles meles L., by studying the patterns of spatial grouping and territory marking, as well as the differences between individuals in some of their characteristics (body condition and dispersal) and in their space use (seasonally, periods of activity and interaction between pairs of individuals) under strong seasonal fluctuations in the availability of the key resource (young rabbits, Oryctolagus cuniculus L.). Finally, the role of the spatial distribution of the main prey (young rabbits) in the development of sociality was also studied in order to test some of the assumptions and predictions of the resource dispersion hypothesis (RDH). 2,Badgers were territorial, showing a flexible system of territory marking, which includes the marking of the most used areas (sett-latrines at the centres of activity) and additionally, at the smaller territories, a system of border-latrines in the areas of contact between territories. The maximum use of border-latrines was associated with the reproductive season, and that of sett-latrines with the season of food scarcity. 3,In the study area where badgers had rabbits as main prey, territories were occupied by small groups of animals, formed by one adult female who reproduced, one adult male who also showed signs of reproductive activity, the cubs of the year (if there was reproduction) and some animals born during previous years, which remained in their natal territory until their dispersal (normally during the mating season of their third or fourth year of life). This system was not strictly fixed as males, given the opportunity, expanded their territories to encompass additional females. Territories in another study site were occupied by one adult female (marked), plus the cubs of the year and another adult individual (unmarked). 4,In winter and spring dominant females and subordinates used only a small fraction of their territories, moved short distances, at a low speed and covering small areas per night. These seasons corresponded with the reproduction of rabbits (highest food availability). Dominant females were the only individuals using all the territory available in the summer (lowest food availability), when badgers had the worst body condition. Food availability increased again in autumn, as did body condition, while range sizes were again reduced. Dominant males used the same proportion of their territories over all seasons. However, in winter (reproductive season) they moved faster, over longer distances, and covered larger areas per period of activity. These results indicate that use of space by dominant males was affected by different factors from that of dominant females and subordinates. 5,RDH does not seem to explain group living in our populations because: (a) territoriality in each pair of primary animals was driven by different factors (trophic resources for females and females for males); (b) dominant males acted as expansionists; and (c) territory size was related to its richness and not to patch dispersion. 6,We propose an integrative hypothesis to explain not only group formation but also interpopulation variability in the social organization of badgers within ecological, demographic and behavioural constraints and in the light of current theory on delayed dispersal. [source] Comparative study on the consequences of culling badgers (Meles meles) on biometrics, population dynamics and movementJOURNAL OF ANIMAL ECOLOGY, Issue 4 2000F. A. M. Tuyttens 1.,Capture,mark,recapture data were used to describe the process of recovery from a typical badger removal operation (BRO) at North Nibley, Gloucestershire, UK, which was carried out as part of the government's strategy to control bovine tuberculosis. Data on biometrics, demographics and movement from this low-density disturbed population were compared with those of two nearby high-density undisturbed populations (Wytham Woods and Woodchester Park, UK) in order to study fundamental principles of population dynamics and density-dependence. 2.,Badgers moved more between social groups at North Nibley than in the other study areas, particularly in the immediate aftermath of the removal operation. 3.,Recolonization of the vacated habitat occurred in the first instance by young females. 4.,Although in the first year after the BRO no cubs had been reared in any of the culled groups, and although the shortage of sexually mature boars may have limited the reproductive output of sows in the following year, the population took only 3 years to recover to its (already lowered) preremoval density. 5.,Losses from the adult (and cub) population due to mortality or emigration were smaller at North Nibley than at the other sites. 6.,There was much evidence that during 1995 and 1996 density-dependent effects constrained the reproductive output of the high-density populations, and some support for the hypothesis that badgers exhibit the non-linear ,large mammal' type of functional response to density. 7.,Badgers at North Nibley were younger, heavier and in better condition than badgers at Wytham Woods and Woodchester Park. 8.,We argue that the disease dynamics are likely to be different in disturbed compared with undisturbed badger populations, and that this could affect the effectiveness of BROs. [source] The role of the Badger (Meles meles) in rabies epizootiology and the implications for Great BritainMAMMAL REVIEW, Issue 1 2002G. C. Smith ABSTRACT The occurrence of a wildlife rabies epizootic in Britain remains a very unlikely event, but it is important to examine all the possible consequences of such an event. Here, I examine the possible role of the European Badger (Meles meles) in such an epizootic. The population density of Badgers in Britain is much higher than that in Europe, and appears to have increased substantially over the last decade or so. The population parameters and epizootiology of rabies in the Badger are reviewed in comparison with the Fox (Vulpes vulpes) and other species. Mustelids appear to be very susceptible to rabies, with the smaller mustelids becoming aggressive, although Badgers do not appear to show heightened aggression when infected. Badger populations on the continent become severely reduced when rabies arrives in the area, and circumstantial evidence strongly suggests that Badgers can easily transmit the virus. Preliminary models support the idea that the Badger could be a very significant secondary host, especially in the initial rabies outbreak. The population recovery rate of the Badger suggests that it is unlikely to become a primary host, although short-term epizootics in the Badger population are likely. The potential for controlling rabies in the Badger is also examined. [source] Mustelid scent-marking in managed ecosystems: implications for population managementMAMMAL REVIEW, Issue 3-4 2000Michael R. Hutchings ABSTRACT Scent-marking is the primary form of communication for mustelids and is important in understanding their sociobiology. In addition, mustelids interact with managed ecosystems or may themselves be managed. However, little is known about the scent-marking behaviour of most mustelids or the impact of management on this behaviour. Mustelids have a number of different scent mark types that can be used for several possible functions, creating a flexible system of varied scent-marking strategies both across and within species. We review the types of scent marks used by European mustelids in relation to their social systems and consider the various hypotheses proposed for their function. Scent-marking behaviour is not fixed for each species, but varies with habitat and population density. We use Badgers (Meles meles) as an example of mustelids acting as reservoirs of disease and Otters (Lutra lutra) as an example of a key conservation species, to demonstrate the applied importance of understanding natural patterns of mustelid scent-marking strategies and the impact of habitat and population management on them. [source] An analysis and review of models of the sociobiology of the MustelidaeMAMMAL REVIEW, Issue 3-4 2000Dominic D. P. Johnson ABSTRACT Classical models of social organization in mustelids suggest that female ranging patterns are determined by the dispersion of resources, whereas those of males are determined by the dispersion of females. However, mating systems and social spacing patterns vary widely both between and within species. For example, European Badgers exhibit a continuum from the classical mustelid model of intra-sexual territoriality and inter-sexual overlap to very large, mixed-sex, promiscuous groups. We evaluated hypotheses and existing data to explain this variation, using comparative analyses and Principal Components Analysis of life history and ecological variables. In addition, we applied a null model of allometric scaling to test for associations between group mass and residual home range size. We found that: (1) the degree of social behaviour and breeding group size increased with life history variables indicative of K-selected strategies of parental investment. (2) Absolute home range size and residual home range size (derived from allometric home range scaling) decreased, paradoxically, with breeding group size and group mass, respectively. These results provide support for ecological theories of social grouping in general and, in particular, for the importance of dispersed resource-rich patches as developed in the Resource Dispersion Hypothesis. [source] Front and Back Covers, Volume 26, Number 2.ANTHROPOLOGY TODAY, Issue 2 2010April 2010 Front cover caption, volume 26 issue 2 A positive, albeit anthropomorphized, view of badgers appears in this illustration for the original edition of the children's classic Wind in the willows. Badgers are shortly to be culled in north Pembrokeshire as part of a Welsh Assembly Government campaign against bovine TB. Pat Caplan's article in this issue discusses the arguments around the cull and the reasons behind the varying positions held by local people on this issue. Back cover caption Witchcraft and Child Sacrifice Above: a poster (supported by NGOs including Save the Children Uganda) against ,child sacrifice' in Uganda, a current topic of concern both to Ugandans and to anthropologists who have criticized media representations of this issue. Below: a Save the Children poster publicizing the main principles of the United Nations Convention on the Rights of the Child, signed by 191 countries. These rights include, among others, the rights to: be protected from being hurt or badly treated in any way; not be kidnapped or sold; be protected from being taken advantage of or exploited in any way; not be punished in a cruel or hurtful way. The article by Pat Caplan in this issue discusses a number of recent BBC broadcasts focused on allegations of witchcraft and child sacrifice, and asks what anthropologists have to offer in terms of understanding such topics. Caplan notes that they can not only contribute their knowledge of the occult in many societies, but also contextualize this realm in terms of historical processes and more material concerns. In addition, anthropologists can suggest links between apparently disparate issues and thereby go beyond surface manifestations. While anthropologists have no monopoly on truth claims, they can sometimes offer alternative explanations and show that things are not always the way they first seem. In order to play an effective role as public intellectuals in this regard, anthropologists need to be willing to grapple pro-actively with such matters of public concern, not least by engaging constructively with the media. [source] Spatial pattern of adult trees and the mammal-generated seed rain in the Iberian pearECOGRAPHY, Issue 3 2010Jose M. Fedriani The degree to which plant individuals are aggregated or dispersed co-determines how a species uses resources, how it is used as a resource, and how it reproduces. Quantifying such spatial patterns, however, presents several methodological issues that can be overcome by using spatial point pattern analyses (SPPA). We used SPPA to assess the distribution of P. bourgaeana adult trees and their seeds (within fecal samples) dispersed by three mammals (badger, fox, and wild boar) within a 72-ha plot across a range of spatial scales. Pyrus bourgaeana trees in our study plot (n=75) were clearly aggregated with a critical spatial scale of ca 25,m, and approximately nine randomly distributed tree clusters were identified. As expected from their marking behaviors, the spatial patterns of fecal deposition varied widely among mammal species. Whereas badger feces and dispersed seeds were clearly clustered at small spatial scales (<10,m), boar and fox feces were relatively scattered across the plot. A toroidal shift null model testing for independence indicated that boars tended to deliver seeds to the vicinity of adult trees and thus could contribute to the maintenance and enlargement of existing tree clusters. Badgers delivered feces and seeds in a highly clumped pattern but unlike boars, away from P. bourgaeana neighborhoods; thus, they are more likely to create new tree clusters than boars. The strong tree aggregation is likely to be the result of one or several non-exclusive processes, such as the spatial patterning of seed delivery by dispersers and seedling establishment beneath mother trees. In turn, the distinctive distribution of P. bourgaeana in Doñana appeared to interact with the foraging behavior of its mammalian seed dispersers, leading to neighbourhood-specific dispersal patterns and fruit-removal rates. Our study exemplifies how a detailed description of patterns generates testable hypotheses concerning the ecology of zoochorous. Pyrus bourgaeana dispersers were unique and complementary in their spatial patterning of seed delivery, which likely confers resilience to their overall service and suggests lack of redundancy and expendability of any one species. [source] The spatial distribution of badgers, setts and latrines: the risk for intra-specific and badger-livestock disease transmissionECOGRAPHY, Issue 4 2008Monika Böhm The spatial distribution of wildlife hosts and the associated environmental distribution of their excretory products are important factors associated with the risk of disease transmission between wildlife and livestock. At a landscape scale, heterogeneous distribution of a wildlife host will create regional hot spots for disease risk, while at the farm level, distributional patterns of wildlife excretory products as well as habitat use are of primary importance to the assessment of disease risk to livestock. In the UK, badgers have been implicated in the transmission of bovine tuberculosis to cattle. In this study, we focus on the spatial and social organization and habitat use of badgers as well as the distributions of their excretions at latrine and sett sites to assess intra- and inter-species (badger,cattle) disease risk. Across the study site, badger latrines and setts were found in prominent clusters, at distances of up to 250 and 200 m respectively. This was partly due to small-scale clustering of latrines around sett sites, so that disease risk may be higher within the vicinity of setts. The clustered distribution suggests that sites of high risk for TB transmission may be localised within farms. Exclusion of cattle from the few sett and latrine sites within their grazing pasture is therefore likely to provide an effective way of reducing the risk of disease transmission. We also found evidence of social sub-division within badger social groups based on differences in the use of main and outlier setts. This may contribute to localised clusters of infection within the badger population, resulting in heterogeneous patterns of environmental disease risk to the wider host community. A greater understanding of variation in host behaviour and its implications for patterns of disease will allow the development of more targeted and effective management strategies for wildlife disease in group-living hosts. [source] Carnivores and their prey in the Wezmeh Cave (Kermanshah, Iran): a Late Pleistocene refuge in the ZagrosINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2009M. Mashkour Abstract Wezmeh Cave is located on the northeastern edge of the Islamabad plain, a high intermontane valley in the western-central Zagros. In 1999 a disturbed but large faunal assemblage was recovered from this site. The abundant and extremely diverse faunal spectra present at Wezmeh Cave has highlighted the importance of this assemblage. Carnivore remains constitute the bulk of the assemblage; red fox (Vulpes vulpes) has the highest number of identified specimens followed by spotted hyena (Crocuta crocuta), brown bear (Ursus arctos), wolf (Canis lupus), felids (lion, leopard, lynx/caracal and wildcat), mustelids (badger, polecat, marten) and viverrids (mongoose). Artiodactyls (bovid, cervid, suid), equids, rhinoceros (Dicerorhinus sp.) and small animals (Cape hare, porcupine, tortoise, snake, birds) are also present. According to U-series dating, the site was occupied from around 70 ka BP through to sub-recent periods by carnivores. Amongst this rich assemblage, a human fossil tooth was also found and dated by non-invasive spectrometry gamma dating to 20,25 ka BP. A preliminary zooarchaeological and taphonomic study shows that Wezmeh Cave was used by multiple carnivore species, a unique phenomenon in the Zagros Mountains in particular and southwest Asia in general. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effects of culling on spatial associations of Mycobacterium bovis infections in badgers and cattleJOURNAL OF APPLIED ECOLOGY, Issue 5 2007HELEN E JENKINS Summary 1Bovine tuberculosis (TB), caused by Mycobacterium bovis, has serious consequences for Britain's cattle industry. European badgers (Meles meles) can transmit infection to cattle, and for many years the British government culled badgers in a series of attempts to reduce cattle infections. 2We investigated the impact of badger culling on the spatial distribution of M. bovis infection in badger and cattle populations in replicated areas in England. 3M. bovis infection was significantly clustered within badger populations, but clustering was reduced when culls were repeated across wide areas. A significant spatial association between M. bovis infections in badgers and cattle herds likewise declined across successive culls. These patterns are consistent with evidence that badgers are less territorial and range more widely in culled areas, allowing transmission to occur over greater distances. 4Prior to culling, M. bovis infections were clustered within cattle populations. Where badger culling was localised, and in unculled areas just outside widespread culling areas, cattle infections became less spatially clustered as badger culling was repeated. This is consistent with expanded badger ranging observed in these areas. 5In contrast, clustering of infection in cattle persisted over time on lands where badgers were repeatedly culled over wide areas. While this lack of a temporal trend must be interpreted with caution, it might reflect persistent infection within, and continued transmission between, cattle herds in areas where transmission from badgers to cattle had been reduced by badger culling. Continued spatial association of infections in cattle and badgers in such areas might partly reflect transmission from cattle. 6Synthesis and applications: Our findings confirm that badger culling can prompt spatial spread of M. bovis infection, a phenomenon likely to undermine the utility of this approach as a disease control measure. Possible evidence of transmission from cattle, both to other cattle and to badgers, suggests that improved cattle controls might yield multiple benefits for TB management. [source] Modelling disease spread in a novel host: rabies in the European badger Meles melesJOURNAL OF APPLIED ECOLOGY, Issue 6 2002G. C. Smith Summary 1Although the red fox Vulpes vulpes is the main reservoir of rabies in Europe, badger Meles meles populations are known to be drastically affected. Models of badger population dynamics are combined with a fox/rabies model to examine the possibility of rabies spread in high-density badger populations, such as those found in the United Kingdom (UK). 2Although some data exist on rabies epizootiology in the badger, there are no data on badger-to-badger contact rates (either healthy or diseased animals). As a starting point consensus expert opinion was used to devise contact probabilities, and the model was found to be insensitive to reasonable variation in these rates for the density of badgers at which these estimates were made. 3Density-dependent (but not density-independent) contact probabilities simulated short chains of infections that may occur in continental Europe at low badger densities, and simulated true epizootics at higher densities. 4Another possible reason for these short chains of infections in continental Europe is a very high level of fragmentation between social groups. 5Given the high level of territorial contiguity and possible contact rates found in some parts of the UK, the model suggests that rabies is capable of spreading within the UK badger population, and a provisional map showing the likelihood of an epizootic is presented. [source] A model of bovine tuberculosis in the badger Melesmeles: an evaluation of control strategiesJOURNAL OF APPLIED ECOLOGY, Issue 3 2001G.C. Smith Summary 1,An individual-based stochastic simulation model was used to investigate the control of bovine tuberculosis (TB) in the European badger Meles meles. Nearly all population and epidemiological parameters were derived from one study site, and the transmission of TB from badgers to cattle was included. The latter is an essential step if reactive badger control strategies are to be modelled. 2,The model appeared to underestimate slightly the rate of population recovery following widespread culling. This may have been due to simulating an isolated population with no immigration and no compensatory increase in fecundity. This should not affect the relative efficacy of each control strategy, but does require further investigation. 3,Of the historical methods of badger control, gassing and the ,clean ring' strategies were the most effective at reducing disease prevalence in the badger and cattle herd breakdown rates. These results agree with those of earlier models. 4,The proactive badger removal operation as part of the current field trial should cause a dramatic decrease in the number of cattle herd breakdowns, but also has the greatest effect on the badger population size. 5,The proactive use of a live test to detect TB, followed by vaccination, appears to reduce substantially cattle herd breakdowns and disease prevalence in the badger. 6,Three combined control strategies gave the best initial reduction in cattle herd breakdown rate and disease prevalence in the badger: (i) a proactive cull followed by reactive test and cull; (ii) a continued vaccination and proactive test and cull; and (iii) a continuous proactive test and cull. 7,The results of simulation models suggest that badger vaccination is a very good method of TB control. This is at odds with simple models and requires further investigation. [source] Differentiating Human Bone from Animal Bone: A Review of Histological MethodsJOURNAL OF FORENSIC SCIENCES, Issue 2 2007Maria L. Hillier M.Sc. ABSTRACT: This review brings together a complex and extensive literature to address the question of whether it is possible to distinguish human from nonhuman bone using the histological appearance of cortical bone. The mammalian species included are rat, hare, badger, racoon dog, cat, dog, pig, cow, goat, sheep, deer, horse, water buffalo, bear, nonhuman primates, and human and are therefore not exhaustive, but cover those mammals that may contribute to a North American or Eurasian forensic assemblage. The review has demonstrated that differentiation of human from certain nonhuman species is possible, including small mammals exhibiting Haversian bone tissue and large mammals exhibiting plexiform bone tissue. Pig, cow, goat, sheep, horse, and water buffalo exhibit both plexiform and Haversian bone tissue and where only Haversian bone tissue exists in bone fragments, differentiation of these species from humans is not possible. Other primate Haversian bone tissue is also not distinguishable from humans. Where differentiation using Haversian bone tissue is undertaken, both the general microstructural appearance and measurements of histological structures should be applied. Haversian system diameter and Haversian canal diameter are the most optimal and diagnostic measurements to use. Haversian system density may be usefully applied to provide an upper and lower limit for humans. [source] Effects of radio-collars on European badgers (Meles meles)JOURNAL OF ZOOLOGY, Issue 1 2002F. A. M. Tuyttens Abstract The relationships between radio-collaring/tracking and 12 biometric parameters in a population of badgers (Meles meles) that were live-trapped in south-west England were investigated. The length of time for which a badger had worn a radio-collar was selected as an explanatory variable in generalized linear models of three biometric parameters (body condition, body weight and testes volume) irrespective of whether or not age class was included as a variable in the analyses. There was evidence that badgers that had been carrying a radio-collar for 1,100 days had lower body condition scores both when compared to badgers that had not been collared and with those that had been collared for longer than 100 days, suggesting a post-collaring acclimation period. In addition, the time period between first and last capture was longer for radio-collared than non-collared badgers. It is unlikely that this was due to an effect of collaring on trappability or to non-random selection of badgers for collaring. Although testes size differed between non-collared badgers and badgers that had been tagged for > 100 days, the relationship between radio-collaring and reproductive output remained unproven. These results highlight not only the need to assess the welfare aspects of radio-collaring but also the potential intricacy of corollaries of collaring. Explorations such as that reported here are important to the validity of studies that make use of radio-telemetry. [source] Incorporating Genotype Uncertainty into Mark,Recapture-Type Models For Estimating Abundance Using DNA SamplesBIOMETRICS, Issue 3 2009Janine A. Wright Summary Sampling DNA noninvasively has advantages for identifying animals for uses such as mark,recapture modeling that require unique identification of animals in samples. Although it is possible to generate large amounts of data from noninvasive sources of DNA, a challenge is overcoming genotyping errors that can lead to incorrect identification of individuals. A major source of error is allelic dropout, which is failure of DNA amplification at one or more loci. This has the effect of heterozygous individuals being scored as homozygotes at those loci as only one allele is detected. If errors go undetected and the genotypes are naively used in mark,recapture models, significant overestimates of population size can occur. To avoid this it is common to reject low-quality samples but this may lead to the elimination of large amounts of data. It is preferable to retain these low-quality samples as they still contain usable information in the form of partial genotypes. Rather than trying to minimize error or discarding error-prone samples we model dropout in our analysis. We describe a method based on data augmentation that allows us to model data from samples that include uncertain genotypes. Application is illustrated using data from the European badger (Meles meles). [source] The spatial distribution of badgers, setts and latrines: the risk for intra-specific and badger-livestock disease transmissionECOGRAPHY, Issue 4 2008Monika Böhm The spatial distribution of wildlife hosts and the associated environmental distribution of their excretory products are important factors associated with the risk of disease transmission between wildlife and livestock. At a landscape scale, heterogeneous distribution of a wildlife host will create regional hot spots for disease risk, while at the farm level, distributional patterns of wildlife excretory products as well as habitat use are of primary importance to the assessment of disease risk to livestock. In the UK, badgers have been implicated in the transmission of bovine tuberculosis to cattle. In this study, we focus on the spatial and social organization and habitat use of badgers as well as the distributions of their excretions at latrine and sett sites to assess intra- and inter-species (badger,cattle) disease risk. Across the study site, badger latrines and setts were found in prominent clusters, at distances of up to 250 and 200 m respectively. This was partly due to small-scale clustering of latrines around sett sites, so that disease risk may be higher within the vicinity of setts. The clustered distribution suggests that sites of high risk for TB transmission may be localised within farms. Exclusion of cattle from the few sett and latrine sites within their grazing pasture is therefore likely to provide an effective way of reducing the risk of disease transmission. We also found evidence of social sub-division within badger social groups based on differences in the use of main and outlier setts. This may contribute to localised clusters of infection within the badger population, resulting in heterogeneous patterns of environmental disease risk to the wider host community. A greater understanding of variation in host behaviour and its implications for patterns of disease will allow the development of more targeted and effective management strategies for wildlife disease in group-living hosts. [source] Spatial organization, group living and ecological correlates in low-density populations of Eurasian badgers, Meles melesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2002Eloy Revilla Summary 1,Territoriality and group living are described in a low-density population of Eurasian badgers, Meles meles L., by studying the patterns of spatial grouping and territory marking, as well as the differences between individuals in some of their characteristics (body condition and dispersal) and in their space use (seasonally, periods of activity and interaction between pairs of individuals) under strong seasonal fluctuations in the availability of the key resource (young rabbits, Oryctolagus cuniculus L.). Finally, the role of the spatial distribution of the main prey (young rabbits) in the development of sociality was also studied in order to test some of the assumptions and predictions of the resource dispersion hypothesis (RDH). 2,Badgers were territorial, showing a flexible system of territory marking, which includes the marking of the most used areas (sett-latrines at the centres of activity) and additionally, at the smaller territories, a system of border-latrines in the areas of contact between territories. The maximum use of border-latrines was associated with the reproductive season, and that of sett-latrines with the season of food scarcity. 3,In the study area where badgers had rabbits as main prey, territories were occupied by small groups of animals, formed by one adult female who reproduced, one adult male who also showed signs of reproductive activity, the cubs of the year (if there was reproduction) and some animals born during previous years, which remained in their natal territory until their dispersal (normally during the mating season of their third or fourth year of life). This system was not strictly fixed as males, given the opportunity, expanded their territories to encompass additional females. Territories in another study site were occupied by one adult female (marked), plus the cubs of the year and another adult individual (unmarked). 4,In winter and spring dominant females and subordinates used only a small fraction of their territories, moved short distances, at a low speed and covering small areas per night. These seasons corresponded with the reproduction of rabbits (highest food availability). Dominant females were the only individuals using all the territory available in the summer (lowest food availability), when badgers had the worst body condition. Food availability increased again in autumn, as did body condition, while range sizes were again reduced. Dominant males used the same proportion of their territories over all seasons. However, in winter (reproductive season) they moved faster, over longer distances, and covered larger areas per period of activity. These results indicate that use of space by dominant males was affected by different factors from that of dominant females and subordinates. 5,RDH does not seem to explain group living in our populations because: (a) territoriality in each pair of primary animals was driven by different factors (trophic resources for females and females for males); (b) dominant males acted as expansionists; and (c) territory size was related to its richness and not to patch dispersion. 6,We propose an integrative hypothesis to explain not only group formation but also interpopulation variability in the social organization of badgers within ecological, demographic and behavioural constraints and in the light of current theory on delayed dispersal. [source] Comparative study on the consequences of culling badgers (Meles meles) on biometrics, population dynamics and movementJOURNAL OF ANIMAL ECOLOGY, Issue 4 2000F. A. M. Tuyttens 1.,Capture,mark,recapture data were used to describe the process of recovery from a typical badger removal operation (BRO) at North Nibley, Gloucestershire, UK, which was carried out as part of the government's strategy to control bovine tuberculosis. Data on biometrics, demographics and movement from this low-density disturbed population were compared with those of two nearby high-density undisturbed populations (Wytham Woods and Woodchester Park, UK) in order to study fundamental principles of population dynamics and density-dependence. 2.,Badgers moved more between social groups at North Nibley than in the other study areas, particularly in the immediate aftermath of the removal operation. 3.,Recolonization of the vacated habitat occurred in the first instance by young females. 4.,Although in the first year after the BRO no cubs had been reared in any of the culled groups, and although the shortage of sexually mature boars may have limited the reproductive output of sows in the following year, the population took only 3 years to recover to its (already lowered) preremoval density. 5.,Losses from the adult (and cub) population due to mortality or emigration were smaller at North Nibley than at the other sites. 6.,There was much evidence that during 1995 and 1996 density-dependent effects constrained the reproductive output of the high-density populations, and some support for the hypothesis that badgers exhibit the non-linear ,large mammal' type of functional response to density. 7.,Badgers at North Nibley were younger, heavier and in better condition than badgers at Wytham Woods and Woodchester Park. 8.,We argue that the disease dynamics are likely to be different in disturbed compared with undisturbed badger populations, and that this could affect the effectiveness of BROs. [source] A simulation model of foraging behaviour and the effect of predation riskJOURNAL OF ANIMAL ECOLOGY, Issue 1 2000Jane F. Ward Summary 1.,The effect of predation risk on the distribution of animals foraging in a patchy environment was explored using a simulation model based on the work of Bernstein, Kacelnik & Krebs (1988, 1991), extended to incorporate predation risk. 2.,Modelled foragers consume prey within patches, having different prey densities, at a rate that depends only on prey density and interference from other foragers in the patch. Prey density remains constant (no depletion). A forager leaves a patch if its intake rate drops below its estimate of the average intake rate available in the environment. This estimate is continually updated by taking a weighted average of current intake and the previous estimate, giving a simple learning process. Decisions on whether to leave are made at regular intervals and a forager leaving a patch may arrive at random at any other patch. 3.,Simulation results were sensitive to the computational scheme used to represent estimates of average intake rate in the environment and to the way in which foragers' decisions were distributed over time, illustrating the need for careful formulation of such models. 4.,Predation risk was modelled as a cost that reduced effective intake, and could be distributed uniformly or skewed to patches of high prey density. The effects of different levels and distributions of predation risk on distribution of foragers were examined using model parameters broadly appropriate to hedgehogs (Erinaceous europaeus L.) foraging for earthworms (Lumbricus spp.) and risking opportunistic predation by badgers (Meles meles L.). The distribution of foragers with respect to prey density took an ,ideal free' form for zero or uniform risk, and was domed when cost of predation risk was relatively high and concentrated in the richer patches, as might be the case when predators and foragers share a common food resource. [source] Effects of culling on spatial associations of Mycobacterium bovis infections in badgers and cattleJOURNAL OF APPLIED ECOLOGY, Issue 5 2007HELEN E JENKINS Summary 1Bovine tuberculosis (TB), caused by Mycobacterium bovis, has serious consequences for Britain's cattle industry. European badgers (Meles meles) can transmit infection to cattle, and for many years the British government culled badgers in a series of attempts to reduce cattle infections. 2We investigated the impact of badger culling on the spatial distribution of M. bovis infection in badger and cattle populations in replicated areas in England. 3M. bovis infection was significantly clustered within badger populations, but clustering was reduced when culls were repeated across wide areas. A significant spatial association between M. bovis infections in badgers and cattle herds likewise declined across successive culls. These patterns are consistent with evidence that badgers are less territorial and range more widely in culled areas, allowing transmission to occur over greater distances. 4Prior to culling, M. bovis infections were clustered within cattle populations. Where badger culling was localised, and in unculled areas just outside widespread culling areas, cattle infections became less spatially clustered as badger culling was repeated. This is consistent with expanded badger ranging observed in these areas. 5In contrast, clustering of infection in cattle persisted over time on lands where badgers were repeatedly culled over wide areas. While this lack of a temporal trend must be interpreted with caution, it might reflect persistent infection within, and continued transmission between, cattle herds in areas where transmission from badgers to cattle had been reduced by badger culling. Continued spatial association of infections in cattle and badgers in such areas might partly reflect transmission from cattle. 6Synthesis and applications: Our findings confirm that badger culling can prompt spatial spread of M. bovis infection, a phenomenon likely to undermine the utility of this approach as a disease control measure. Possible evidence of transmission from cattle, both to other cattle and to badgers, suggests that improved cattle controls might yield multiple benefits for TB management. [source] Effects of culling on badger Meles meles spatial organization: implications for the control of bovine tuberculosisJOURNAL OF APPLIED ECOLOGY, Issue 1 2006ROSIE WOODROFFE Summary 1The incidence of bovine tuberculosis (TB) in British cattle has risen markedly over the last two decades. Failure to control the disease in cattle has been linked to the persistence of a reservoir of infection in European badgers Meles meles, a nationally protected species. Although badger culling has formed a component of British TB control policy for many years, a recent large-scale randomized field experiment found that TB incidence in cattle was no lower in areas subject to localized badger culling than in nearby areas where no experimental culls occurred. Indeed, analyses indicated that cattle incidence was higher in culled areas. 2One hypothesis advanced to explain this pattern is that localized culling disrupted badgers' territorial behaviour, potentially increasing the rate of contact between cattle and infected badgers. This study evaluated this hypothesis by investigating badger activity and spatial organization in 13 study areas subjected to different levels of culling. Badger home ranges were mapped by feeding colour-marked baits at badger dens and measuring the geographical area in which colour-marked faeces were retrieved. 3Badger home ranges were consistently larger in culling areas. Moreover, in areas not subjected to culling, home range sizes increased with proximity to the culling area boundary. Patterns of overlap between home ranges were also influenced by culling. 4Synthesis and applications. This study demonstrates that culling badgers profoundly alters their spatial organization as well as their population density. These changes have the potential to influence contact rates between cattle and badgers, both where culls occur and on adjoining land. These results may help to explain why localized badger culling appears to have failed to control cattle TB, and should be taken into account in determining what role, if any, badger culling should play in future control strategies. [source] Modelling disease spread in a novel host: rabies in the European badger Meles melesJOURNAL OF APPLIED ECOLOGY, Issue 6 2002G. C. Smith Summary 1Although the red fox Vulpes vulpes is the main reservoir of rabies in Europe, badger Meles meles populations are known to be drastically affected. Models of badger population dynamics are combined with a fox/rabies model to examine the possibility of rabies spread in high-density badger populations, such as those found in the United Kingdom (UK). 2Although some data exist on rabies epizootiology in the badger, there are no data on badger-to-badger contact rates (either healthy or diseased animals). As a starting point consensus expert opinion was used to devise contact probabilities, and the model was found to be insensitive to reasonable variation in these rates for the density of badgers at which these estimates were made. 3Density-dependent (but not density-independent) contact probabilities simulated short chains of infections that may occur in continental Europe at low badger densities, and simulated true epizootics at higher densities. 4Another possible reason for these short chains of infections in continental Europe is a very high level of fragmentation between social groups. 5Given the high level of territorial contiguity and possible contact rates found in some parts of the UK, the model suggests that rabies is capable of spreading within the UK badger population, and a provisional map showing the likelihood of an epizootic is presented. [source] A model of bovine tuberculosis in the badger Melesmeles: an evaluation of control strategiesJOURNAL OF APPLIED ECOLOGY, Issue 3 2001G.C. Smith Summary 1,An individual-based stochastic simulation model was used to investigate the control of bovine tuberculosis (TB) in the European badger Meles meles. Nearly all population and epidemiological parameters were derived from one study site, and the transmission of TB from badgers to cattle was included. The latter is an essential step if reactive badger control strategies are to be modelled. 2,The model appeared to underestimate slightly the rate of population recovery following widespread culling. This may have been due to simulating an isolated population with no immigration and no compensatory increase in fecundity. This should not affect the relative efficacy of each control strategy, but does require further investigation. 3,Of the historical methods of badger control, gassing and the ,clean ring' strategies were the most effective at reducing disease prevalence in the badger and cattle herd breakdown rates. These results agree with those of earlier models. 4,The proactive badger removal operation as part of the current field trial should cause a dramatic decrease in the number of cattle herd breakdowns, but also has the greatest effect on the badger population size. 5,The proactive use of a live test to detect TB, followed by vaccination, appears to reduce substantially cattle herd breakdowns and disease prevalence in the badger. 6,Three combined control strategies gave the best initial reduction in cattle herd breakdown rate and disease prevalence in the badger: (i) a proactive cull followed by reactive test and cull; (ii) a continued vaccination and proactive test and cull; and (iii) a continuous proactive test and cull. 7,The results of simulation models suggest that badger vaccination is a very good method of TB control. This is at odds with simple models and requires further investigation. [source] Tuberculosis and badgers: new approaches to diagnosis and controlJOURNAL OF APPLIED MICROBIOLOGY, Issue 2003E. Gormley First page of article [source] Historical and contemporary distributions of carnivores in forests of the Sierra Nevada, California, USAJOURNAL OF BIOGEOGRAPHY, Issue 8 2005William J. Zielinski Abstract Aim, Mammalian carnivores are considered particularly sensitive indicators of environmental change. Information on the distribution of carnivores from the early 1900s provides a unique opportunity to evaluate changes in their distributions over a 75-year period during which the influence of human uses of forest resources in California greatly increased. We present information on the distributions of forest carnivores in the context of two of the most significant changes in the Sierra Nevada during this period: the expansion of human settlement and the reduction in mature forests by timber harvest. Methods, We compare the historical and contemporary distributions of 10 taxa of mesocarnivores in the conifer forests of the Sierra Nevada and southern Cascade Range by contrasting the distribution of museum and fur harvest records from the early 1900s with the distribution of detections from baited track-plate and camera surveys conducted from 1996 to 2002. A total of 344 sample units (6 track plates and 1 camera each) were distributed systematically across c. 3,000,000 ha area over a 7-year period. Results, Two species, the wolverine (Gulo gulo) and the red fox (Vulpes vulpes), present in the historical record for our survey area, were not detected during the contemporary surveys. The distributions of 3 species (fisher [Martespennanti], American marten [M. americana], and Virginia opossum [Didelphisvirginiana]) have substantially changed since the early 1900s. The distributions of fishers and martens, mature-forest specialists, appeared to have decreased in the northern Sierra Nevada and southern Cascade region. A reputed gap in the current distribution of fishers was confirmed. We report for the first time evidence that the distribution of martens has become fragmented in the southern Cascades and northern Sierra Nevada. The opossum, an introduced marsupial, expanded its distribution in the Sierra Nevada significantly since it was introduced to the south-central coast region of California in the 1930s. There did not appear to be any changes in the distributions of the species that were considered habitat generalists: gray fox (Urocyon cinereoargenteus), striped skunk (Mephitis mephitis), western spotted skunk (Spilogale gracilis), or black bear (Ursus americanus). Detections of raccoons (Procyon lotor) and badgers (Taxidea taxus) were too rare to evaluate. Contemporary surveys indicated that weasels (M. frenata and M. erminea) were distributed throughout the study area, but historical data were not available for comparison. Main conclusions, Two species, the wolverine and Sierra Nevada red fox, were not detected in contemporary surveys and may be extirpated or in extremely low densities in the regions sampled. The distributions of the mature forest specialists (marten and fisher) appear to have changed more than the distributions of the forest generalists. This is most likely due to a combination of loss of mature forest habitat, residential development and the latent effects of commercial trapping. Biological characteristics of individual species, in combination with the effect of human activities, appear to have combined to affect the current distributions of carnivores in the Sierra Nevada. Periodic resampling of the distributions of carnivores in California, via remote detection methods, is an efficient means for monitoring the status of their populations. [source] Exploitation of food resources by badgers (Meles meles) in the Swiss Jura MountainsJOURNAL OF ZOOLOGY, Issue 2 2005C. Fischer Abstract In our study three badger Meles meles populations separated by only a few km but subjected to different environmental conditions were compared. Differences are especially marked for climatic factors, the three areas being located at different altitudes, and for intensivity of soil use by people. The diet of the three populations was significantly different, with one or two dominant items in each area: mammals and cereals in the mountain, maize in the mid-mountain and in the lowland areas. In the most intensively cultivated area, maize was the most consumed item in autumn and spring, several months after harvesting. Earthworms had only a secondary importance in the diet in the mountainous area, but were negligible in the mid-mountain and lowland areas. Soil management seemed to play a preponderant role, mostly owing to soil quality and topography. Climate seemed to have a secondary effect only. [source] | ||||||||||||||||