156 research outputs found

    Die Anwendung von Mikrosatelliten zum Studium der Sozialstruktur bei GroßsĂ€ugetieren : am Beispiel von italienischem Wolf und Damwild

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    Scandura M. The use of microsatellites in the study of social structure in large mammals : Italian wolf and fallow deer as case studies. Bielefeld (Germany): Bielefeld University; 2004.The content of the present PhD thesis deals with the application of microsatellite analysis to the study of two species of large mammals, referring to some aspects of their social and mating systems. The Italian wolf (Canis lupus) and the fallow deer (Dama dama) were chosen as case studies, since genetic investigations on their populations result, for different reasons, problematic. The wolf in Italy is a particularly protected species, recovering throughout the peninsula from the effects of a recent bottleneck. Sampling wolves may not rely on capturing or killing them, therefore an alternative, non-invasive, approach was adopted in my study. Scats, shed hairs and blood drops collected on the snow represented the main source of DNA for the analysis. Methodological cares were necessary to obtain reliable wolf genotypes. A set of ten canine microsatellites was employed to achieve unique multilocus genotypes in the population. Fifty-two individuals were typed in the period 1998 - 2003. In some cases, pack composition was determined, confirming that familiar bonds are at the basis of wolf social units. An unpredictable high local differentiation was found among geographic areas. Early dispersal seem to be common in the population, but its effects on the gene flow are not detectable, at least at my study scale. I proposed that most of this dispersal may be unsuccessful or over long distances. The study population, indeed, seem to have reached a high level of local saturation, with clumped pack territories and high reproductive rates, and thus possibly represents a source, from which wolves disperse toward sink areas. The second study involves an enclosed population of fallow deer. Lekking is seldom observed in mammals, and among them, it is more common in ungulate species. Fallow deer is one of the most studied lekking ungulate and this particular population is object of long-term researches on male mating strategies. Mature bucks in the population join into leks during the breeding season: a costly strategy, which apparently does not guarantee high direct benefits (fitness). In this study, for the first time, I used a molecular approach to verify the existence of a genetic basis to lek formation. The recourse to microsatellites enabled to overcome the strong limitation due to the extremely monomorphism of the species, documented in several studies. Though the low variability even at microsatellite loci, the hypotheses of kin selection (territorial bucks in a lek are relatives) and of heterozygosity advantage (territorial bucks in a lek have an overall high heterozygosity) were tested and resulted not supported by data. Hence, future studies should be addressed towards phenotypic variation and consider in detail physiological and ecological factors, in order to clarify the reasons why lekking takes place in fallow deer

    Long-lasting, kin-directed female interactions in a spatially structured wild boar social network

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    We thank W. Jędrzejewski for his support and logistical help in trapping wild boar. We are grateful to R. Kozak, A. Waszkiewicz and many students and volunteers for their help with fieldwork as well as to A. N. Bunevich, T. Borowik and local hunters for providing genetic samples. Genetic analyses were performed in the laboratory of the Department of Science for Nature and Environmental Resources, University of Sassari, Italy, with the help of L. Iacolina and D. Biosa. We are grateful to K. O’Mahony who revised English and to A. Widdig, K. Langergraber and one anonymous reviewer for valuable comments on the earlier version of the manuscript.Peer reviewedPublisher PD

    Trophic overlap between wolves and free-ranging wolf × dog hybrids in the Apennine Mountains, Italy

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    Hybridization between wolves (Canis lupus) and domestic dogs (Canis familiaris) can represent a threat to wild populations via genetic introgression and ecological competition. Therefore understanding the ecological role of hybrids may be crucial for developing appropriate conservation strategies. The Italian wolf population has a peculiar genetic composition due to a long-lasting geographic isolation. Nowadays, however, its genetic integrity is threatened by the spread of canine genes as a result of the hybridization with stray dogs in the wild. The aim of the present study was to gain insights into the ecological role of free-ranging wolf–dog hybrids by investigating their winter food habits in comparison with wolves in a mountain area of Central Italy. Levels of genetic introgression from the dogs were assessed in two adjacent areas occupied by up to five different packs by analyzing non-invasive samples and carcasses collected therein with a set of uniparental and bi-parental molecular markers. The obtained results enabled us to classify the two areas as 'hybrid' and 'wolf' areas based on their level of genetic introgression. Trophic niche and similarity/dissimilarity analyses did not detect significant difference in the diet between the two areas: in both of them, wild boar was the main prey, followed by roe deer. Furthermore, the same age/body mass classes of the two ungulates were selected by wolves and hybrids. Our findings confirmed wolf–dog hybrids as potential competitors for wolves. Further studies on other aspects of their biology and ecology are recommended in order to better estimate the impact of hybridization on natural wolf populations

    A Predator on the Doorstep: Kill Site Selection by a Lone Wolf in a Peri-Urban Park in a Mediterranean Area

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    The aim of the study was to assess which kill site characteristics were selected by a lone wolf living in a protected Mediterranean coastal area near the city of Pisa, Italy, where both wild and domestic ungulates were available as potential prey. Between 2017 and 2019, we monitored the wolf’s predatory behaviour through a combination of camera trapping and active search for kill sites and prey carcasses. The main prey found was the fallow deer (n = 82); only two wild boars and no domestic ungulates were found preyed upon. The features and habitat ofkill sites were modelled to test for selection by the wolf. The habitat type of kill site was composed of meadows and pastures (89.3%), woods (7.3%), degraded coastal areas (1.9%), roads and rivers (1.1%), and marshes (0.5%). We calculated their distance from landscape features and ran a binomial generalised linear model to test the influence of such landscape variables. The distance of kill sites from landscape elements was significantly different from random control sites, and a positive selection for fences was found. In fact, the wolf pushed fallow deer towards a fence to constrain them and prevent them from es-caping. We also analysed the body condition of predated fallow deer as a percentage of fat content in the bone marrow of the hind legs. Our results revealed the selection of the lone wolf for deer in good body condition. This is a possible outcome of the habitat selection shown by fallow deer in the study area, where fenced open pastures are the richest in trophic resources; therefore, our findingssuggest a high efficacy for the lone wolf hunting strategy, but also the adoption of a high risk feed-ing strategy by deer. This study suggests that a lone predator can take advantage of human infra-structures to maximise its predatory effectiveness

    Contemporary genetic structure, phylogeography and past demographic processes of wild boar <i>Sus scrofa</i> population in central and eastern Europe

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    The wild boar (Sus scrofa) is one of the most widely distributed mammals in Europe. Its demography was affected by various events in the past and today populations are increasing throughout Europe. We examined genetic diversity, structure and population dynamics of wild boar in Central and Eastern Europe. MtDNA control region (664 bp) was sequenced in 254 wild boar from six countries (Poland, Hungary, Belarus, Ukraine, Moldova and the European part of Russia). We detected 16 haplotypes, all known from previous studies in Europe; 14 of them belonged to European 1 (E1) clade, including 13 haplotypes from E1-C and one from E1-A lineages. Two haplotypes belonged respectively to the East Asian and the Near Eastern clade. Both haplotypes were found in Russia and most probably originated from the documented translocations of wild boar. The studied populations showed moderate haplotype (0.714 &#177;0.023) and low nucleotide diversity (0.003 &#177;0.002). SAMOVA grouped the genetic structuring of Central and Eastern European wild boar into three subpopulations, comprising of: (1) north-eastern Belarus and the European part of Russia, (2) Poland, Ukraine, Moldova and most of Belarus, and (3) Hungary. The multimodal mismatch distribution, Fu's Fs index, Bayesian skyline plot and the high occurrence of shared haplotypes among populations did not suggest strong demographic fluctuations in wild boar numbers in the Holocene and pre-Holocene times. This study showed relatively weak genetic diversity and structure in Central and Eastern European wild boar populations and underlined gaps in our knowledge on the role of southern refugia and demographic processes shaping genetic diversity of wild boar in this part of Europe

    Mitochondrial DNA Variation among Dogs of Mongolian, Tuvinian and Altaic Nomads

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    Dogs originated from the domestication of Eurasian grey wolves. From a genetic viewpoint, they can be grouped into two main clusters: the first is represented by several breeds obtained by artificial selection, whereas the second is of dogs that adapted to a human commensal lifestyle. Here we have provided a molecular survey aimed to infer on the genetic variability of dogs from nomadic camps in Mongolia, and the Republics of Tuva and Altai belonging to the Russian Federation. The results provided evidence of typical marks of expanding populations with multiple origins. Such a scenario could be the result of genetic exchanges among dogs from different camps, that were likely mediated by nomads
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