Conservation Genetics of Scandinavian Wolverines

University dissertation from Uppsala : Acta Universitatis Upsaliensis

Abstract: In this thesis, genetic methods for individual identification and sex determination of wolverines from non-invasive samples were developed and applied in genetic monitoring of Scandinavian wolverine populations. Paternity and mating system of wolverines were studied by combining genetic analysis with telemetry data. Moreover, the possibility to obtain DNA from claws left on tanned carnivore hides was investigated.Non-invasive genetic sampling was effective in revealing important population parameters. For the subpopulation in southern Norway, a population size of approximately 90 individuals, an equal sex ratio and similar levels of genetic diversity as in the main Scandinavian population were revealed. Genetic erosion in this small population has likely been counteracted by immigration of individuals from the main population since its re-establishment around 1970.During the 1990s, two areas in east-central Sweden were colonised by wolverines. In a survey comprising 400 non-invasive samples collected during five winters, a total of 22 wolverines were detected. Genetic data suggest that inbreeding has occurred in both areas and that the two populations were founded by as few as 2-4 individuals. These findings suggest that gene flow from the main population is crucial for their survival even in a short time perspective. The detection of occasional stray individuals from the main population shows that this is indeed feasible. Paternity analysis of 145 wolverine offspring in northern Sweden and southern Norway confirmed a polygamous mating system in wolverines. Breeding pair formation was generally consistent with the territories held by males and females, i.e. breeding pairs had overlapping territories. In the majority of litters, siblings were assigned the same father, thus indicating that multiple paternity is rare. Tanning is a common form of preservation of mammalian specimens that normally precludes genetic analysis. Nevertheless, I demonstrate the possibility to successfully extract and amplify DNA from claws left on tanned carnivore hides.