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1. The partition of the ecological niche can enhance the coexistence of predators due to differences in how they exploit three main resources: food, space, and time, the latter being an axis that often remains unexplored. 2. We studied niche segregation in a Mediterranean mesocarnivore community composed by Vulpes vulpes, Genetta genetta, Meles meles, and Herpestes ichneumon, addressing simultaneously different niche axes: the temporal, trophic, and spatial axes. 3. We assessed temporal segregation between mesopredators and prey and between potential competitors, using camera trap data between 2018 and 2020 in a Mediterranean landscape in Southern Spain. We deployed camera traps in 35 stations in three sites with varying vegetation cover within Doñana National Park. We further examined the spatial overlap in activity centers and trophic preferences between potential competitors using diet information from studies performed in the study area. 4. We found an overall temporal segregation between trophic generalist species, with species showing higher temporal overlap differing in their trophic preferences and/or showing limited spatial overlap. Furthermore, we observed an overall high overlap between the activity patterns of predators and their major prey in the area (the common genet vs. small mammals and the red fox vs. European rabbit). 5. Our study suggests that coexistence of the different species that compose the mesocarnivore assemblage in Mediterranean landscapes can be facilitated by subtle differences along the three main niche axes, with temporal segregation being a most pronounced mechanism. Our findings reinforce the idea that the coexistence mechanisms underlying community structure are multidimensional. [ABSTRACT FROM AUTHOR]

Abstract: We studied the habitat selection patterns of badgers Meles meles (Linnaeus, 1758) in Mediterranean semi-arid ecosystems. Fifty-seven plots were sampled in two semi-arid regions of Spain. In each plot, badger latrines were located along 2.6 km transects. The number of badger latrines per km was used as a surrogate of badger abundance and as an index of habitat selection by badgers. For each plot, a series of environmental variables were measured at two spatial scales. These variables were related to land use and vegetation formation parameters that are considered potentially important for habitat requirements (i.e., food and shelter). The habitat selection model was carried out using generalised linear models (GLM) and an information-theoretic approach. Results indicated that badgers prefer fruit orchards, and shrub and rock-covered areas, which provide additional trophic and shelter resources, and avoid intensively cultivated fields and human settlements. We conclude that badger conservation in semi-arid environments of the Iberian Peninsula requires the existence of fruit orchards and the limitation of human development. Policies restraining agriculture intensification would encourage traditional or new non-intensive agricultural practices and increase shrub-patch availability, which would benefit this species. [Copyright &y& Elsevier]

Abstract: Despite the compulsory test and slaughter campaigns in cattle, bovine tuberculosis (bTB) is still present in Spain, and the role of wildlife reservoirs is increasingly recognized. We provide an update on recent progress made in bTB control in Spanish wildlife, including aspects of epidemiology, surveillance, host–pathogen interaction and wildlife vaccination. At the high densities and in the particular circumstances of Mediterranean environments, wild ungulates, mainly Eurasian wild boar and red deer, are able to maintain Mycobacterium bovis circulation even in absence of domestic livestock. Infection is widespread among wild ungulates in the south of the country, local infection prevalence being as high as 52% in wild boar and 27% in red deer. Risk factors identified include host genetic susceptibility, abundance, spatial aggregation at feeders and waterholes, scavenging, and social behaviour. An increasing trend of bTB compatible lesions was reported among wild boar and red deer inspected between 1992 and 2004 in Southwestern Spain. Sporadic cases of badger TB have been detected, further complicating the picture. Gene expression profiles were characterized in European wild boar and Iberian red deer naturally infected with M. bovis. The comparative analysis of gene expression profiles in wildlife hosts in response to infection advanced our understanding of the molecular mechanisms of infection and pathogenesis, revealed common and distinctive host responses to infection and identified candidate genes associated with resistance to bTB and for the characterization of host response to infection and vaccination. Ongoing research is producing valuable knowledge on vaccine delivery, safety and efficacy issues. Baits for the oral delivery of BCG vaccine preparations to wild boar piglets were developed and evaluated. The use of selective feeders during the summer was found to be a potentially reliable bait-deployment strategy. Safety experiments yielded no isolation of M. bovis BCG from faeces, internal organs at necropsy and the environment, even after oral delivery of very high doses. Finally, preliminary vaccination and challenge experiments suggested that a single oral BCG vaccination may protect wild boar from infection by a virulent M. bovis field strain. [Copyright &y& Elsevier]

We chose the interaction between the Mediterranean dwarf palm (Chamaerops humilis) and its major seed disperser, the Eurasian badger (Meles meles), to evaluate the hypothesis that endozoochory is characterized by a mixture of conflicting and overlapping interests, with the capacity of being positive or negative for plant fitness. For instance, because of the potential protective role against invertebrate seed predators of C. humilis pulp, we expected that badger-ingested diaspores (i.e., seeds without pulp) would show lower survival than control seeds with the pulp attached. Conversely, due to the possible germination inhibitory function of C. humilis fruit pulp, it was also likely that badger-ingested seeds germinate in higher proportion than control seeds. We evaluated our predictions by carrying out a field sowing and monitoring it over two years. We estimated several stage-specific transition probabilities as well as the cumulative probability of seedling recruitment under different treatments. Our experimental results revealed the multifunctionality of C. humilis fruit pulp and that fruit ingestion by badgers had conflicting outcomes for the palm. As predicted, seed survival was much lower and seed predation by invertebrates much higher for badger-ingested than for control seeds, suggesting a defensive role of C. humilis ripe fruit pulp. All early-emerged seedlings came from badger-ingested seeds, suggesting an inhibitory function of fruit pulp. Though we did not find an effect of removal from the maternal environment on most components of fitness, seedling survival for badger-ingested seeds was higher away from than beneath conspecifics. Badgers imposed a sizeable short-term fitness cost to C. humilis and therefore could be categorized as a "dangerous liaison." Nonetheless, because of the high mobility of the badger, its dispersal service appears paramount given the severe fragmentation and isolation of most C. humilis populations across the highly humanized Mediterranean basin. Our study thus illustrates the necessity of assessing concurrently direct and indirect effects of plant-disperser interactions at different stages of the plant life cycle and recruitment process. [ABSTRACT FROM AUTHOR]

The helminthological study of 26 Eurasian badgers ( Meles meles L.) in the Basque Country (northern Spain) revealed the presence of two trematode ( Euryhelmis squamula and Brachylaima sp.), three cestode ( Atriotaenia incisa, Mesocestoides sp. and Taenia sp.) and five nematode ( Aonchotheca putorii, Physaloptera sp., Molineus patens, Uncinaria criniformis and Strongyloides sp.) species. All 15 individuals analysed for Trichinella sp. were negative. The coprological analysis (flotation and migration) revealed the excretion of strongylid, capillariid and trematode eggs, and Crenosoma sp. and Angiostrongylus sp. larvae. No sex- or age-related differences were found in the parasite burden or egg and larvae excretion. A. incisa and M. patens abundances were positively correlated, both species being negatively correlated with badger weight. The presence of adults of U. criniformis and strongylid eggs in faeces was not independent. Badgers excreting Angiostrongylus larvae were in poorer condition than those not excreting. [ABSTRACT FROM AUTHOR]

SummaryAim This paper describes the distribution pattern (occurrence) of badgers (Meles meles L. 1758) in a Mediterranean mountain area of central Spain, in relation to landscape characteristics and climatic data. We test the fit of the badger occurrence pattern to the niche hypothesis predictions. Location We sampled twenty-four survey plots randomly distributed in the mountains of central Spain (Sierra de Guadarrama, Madrid): ten in the north and fourteen in the south slopes. All habitat types and climatic conditions typical of central Spain can be found. Methods The ocurrence of badgers in the plots were recorded through an exhaustive search of setts and latrines in four different (and evenly spaced) points in each plot. The index of occurrence was made by dividing the number of positive points (badger presence) by the total number of points sampled (four in all plots). Landscape patterns (% type of habitat in each plot) were obtained from detailed maps and climate data from meteorological stations placed in the plot. We analyse the contribution of landscape variables and climate data to explain the differences in badger occurrence through Pearson correlations and fixed one-way ANCOVA with climatic data as fixed factor, vegetation cover as covariates and badger occurrence as response variable. Additionally, we use an one-way ANOVA to check the differences in occurrence between north and south plots with the location of each plot as fixed factor. Results The results indicate that the badger is more abundant in rainy areas of the mountains, and in open landscapes vegetated by ash-tree forests than in closed landscapes vegetated by holm oak forests. In addition, the species is more abundant in the northern plots than in the southern ones. Northern plots were homogeneous areas characterized by their open landscape and wet climate, while southern plots were characterized by their dry climate and closed landscapes. In addition, climate (measured as summer rain) is more determinant than habitat type (holm oak cover) to explain the pattern of badger occurrence. Main conclusions Overall, we consider that the typical Mediterranean landscapes are poor habitats for badgers due to changes in the environmental conditions associated with concomitant changes in food resources. These data support the niche hypothesis to explain the changes in abundance or occurrence close to the edge of the distribution of species, and in particular, in Palearctic species in the Mediterranean area. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of the present work was to investigate the prevalence, spatial distribution, and temporal distribution of tuberculosis in 673 free-ranging Eurasian badgers (Meles meles) and cattle from Asturias (Atlantic Spain) during a 13-year follow-up. The study objective was to assess the role of badgers as a reservoir of tuberculosis for cattle and other sympatric wild species in the region. During the follow-up, 27/639 badgers (4.23%) were positive for the Mycobacterium tuberculosis complex based on bacterial isolation, while 160/673 (23.77%) were positive based on P22 ELISA. Badger infection was spatially and temporally associated with cattle herd infection. The present work investigated the prevalence, spatial distribution, and temporal distribution of tuberculosis (TB) in free-ranging Eurasian badgers (Meles meles) and cattle in Asturias (Atlantic Spain) during a 13-year follow-up. The study objective was to assess the role of badgers as a TB reservoir for cattle and other sympatric wild species in the region. Between 2008 and 2020, 673 badgers (98 trapped and 575 killed in road traffic accidents) in Asturias were necropsied, and their tissue samples were cultured for the Mycobacterium tuberculosis complex (MTC) isolation. Serum samples were tested in an in-house indirect P22 ELISA to detect antibodies against the MTC. In parallel, data on MTC isolation and single intradermal tuberculin test results were extracted for cattle that were tested and culled as part of the Spanish National Program for the Eradication of Bovine TB. A total of 27/639 badgers (4.23%) were positive for MTC based on bacterial isolation, while 160/673 badgers (23.77%) were found to be positive with the P22 ELISA. The rate of seropositivity was higher among adult badgers than subadults. Badger TB status was spatially and temporally associated with cattle TB status. Our results cannot determine the direction of possible interspecies transmission, but they are consistent with the idea that the two hosts may exert infection pressure on each other. This study highlights the importance of the wildlife monitoring of infection and disease during epidemiological interventions in order to optimize outcomes. [ABSTRACT FROM AUTHOR]

We provide a temporal overview (from 2012 to 2018) of the outcomes of tuberculosis (TB) in the cattle and badger populations in a hot-spot in Asturias (Atlantic Spain). We also study the badger's spatial ecology from an epidemiological perspective in order to describe hazardous behavior in relation to TB transmission between cattle and badgers. Culture and single intradermal tuberculin test (SITT) were available for cattle as part of the National Program for the Eradication of TB. A field survey was also carried out in order to determine the paddocks and buildings used by each farm, and the information obtained was stored by using geographic information systems. Moreover, eighty-three badgers were submitted for necropsy and subsequent bacteriological studies. Ten badgers were also tracked, using global positioning system (GPS) collars. The prevalence of TB in cattle herds in the hot-spot increased from 2.2% in 2012 to 20% in 2016; it then declined to 0.0% in 2018. In contrast, the TB prevalence in badgers increased notably (from 5.55% in 2012–2015 to 10.64% in 2016–2018). Both cattle and badgers shared the same strain of Mycobacterium bovis. The collared badgers preferred paddocks used by TB-positive herds in spring and summer (when they were more active). The males occupied larger home ranges than the females (Khr95: males 149.78 ± 25.84 ha and females 73.37 ± 22.91 ha; Kcr50: males 29.83 ± 5.69 ha and females 13.59 ± 5.00 ha), and the home ranges were smaller in autumn and winter than in summer. The averages of the index of daily and maximum distances traveled by badgers were 1.88 ± (SD) 1.20 km and 1.99 ± 0.71 km, respectively. One of them presented a dispersive behavior with a maximum range of 18.3 km. The most preferred habitat was apple orchards in all seasons, with the exception of winter, in which they preferred pastures. Land uses and landscape structure, which have been linked with certain livestock-management practices, provide a scenario of great potential for badger–cattle interactions, thus enhancing the importance of the badgers' ecology, which could potentially transmit TB back to cattle in the future. [ABSTRACT FROM AUTHOR]

Recent studies suggest that badgers may be a potential reservoir of Mycobacterium bovis infection for cattle in Northern Spain. The objective of this study was to investigate potential epidemiological links between cattle and badgers. Culture and molecular typing data were available for cattle culled during the national tuberculosis (TB) eradication campaigns between 2008 and 2012, as well as from 171 necropsied badgers and 60 live animals trapped and examined over the same time period. Mycobacterium tuberculosis complex strains were isolated from pooled tissues of 14 (8.2%) necropsied badgers, of which 11 were identified as M. bovis: six different spoligotypes of M. bovis were subsequently identified. In two geographical locations where these isolates were shared between cattle and badgers, infected cattle herds and badgers lived in close contact. Although it remains unclear if badgers are a maintenance or spill-over host of M. bovis in this setting, it would appear prudent to have precautionary measures in place to reduce contact between cattle and badgers., (Copyright © 2013 Elsevier Ltd. All rights reserved.)