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European Badgers (european + badger)
Selected AbstractsThe 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] 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] 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] 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 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. 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