Julia Schregel

Home ranges and densities of medium-sized carnivores in south-east Finland, with special reference to rabies spread.

Home ranges and densities of medium-sized carnivores were studied in south-east Finland by radio tracking. The species studied included potential vectors of rabies: the raccoon dogNyctereutes procyonoides (Gray, 1834), red foxVulpes vulpes (Linnaeus, 1758), European badgerMeles meles (Linnaeus, 1758) and domestic catFelis silvestris catus (Schreber, 1777). Home ranges of badgers were largest (mean 14.7 km2) and those of cats smallest (1.5 km2). Home ranges overlapped largely, both within and between species. Most home ranges were larger and population densities lower in south-east Finland compared with those in Western Europe. The pooled density of medium-sized carnivores with overlapping home ranges was, however, high, which may indicate a high risk of a rabies epizootic in this multi-host community. Rabies might also spread rapidly to new areas, because of the large home ranges and, consequently, long dispersal distances.

Habitat impact on raccoon dog Nyctereutes procyonoides home range size in southern Finland

Monogamous canid home range size is often negatively correlated with population density. Home range size, in turn, may be affected by the habitat. Here we examined landscape features that may affect home range size of the invasive raccoon dogNyctereutes procyonoides (Gray, 1834), an important vector of diseases and parasites in Europe. The aim was thus to reveal the habitats where population density and the risk for epizootics is highest. We radio tracked 42 raccoon dogs in three areas in southern Finland between 2001 and 2007. There was an inverse relationship between home range size and the proportions of meadows and gardens, as well as habitat richness. Also mixed forests were more common in areas where home ranges were small. The risk for epizootics, such as rabies, is thus highest in areas which constitute of a mosaic of small patches of meadows, gardens and mixed forests. The preventive measures, such as bait vaccinations, against epizootics should therefore be concentrated in these areas which are mainly in and around villages.

Genetic evidence of female kin clusters in a continuous population of a solitary carnivore, the Eurasian lynx

Abstract Large terrestrial carnivores can sometimes display strong family bonds affecting the spatial distribution of related individuals. We studied the spatial genetic relatedness and family structure of female Eurasian lynx, continuously distributed in southern Finland. We hypothesized that closely related females form matrilineal assemblages, clustering together with relatives living in the neighboring areas. We evaluated this hypothesis using tissue samples of 133 legally harvested female lynx (from year 2007 to 2015), genotyped with 23 microsatellite markers, and tested for possible spatial genetic family structure using a combination of Bayesian clustering, spatial autocorrelation, and forensic genetic parentage analysis. The study population had three potential family genetic clusters, with a high degree of admixture and geographic overlap, and showed a weak but significant negative relationship between pairwise genetic and geographic distance. Moreover, parentage analysis indicated that 64% of the females had one or more close relatives (sister, mother, or daughter) within the study population. Individuals identified as close kin consistently assigned to the same putative family genetic cluster. They also were sampled closer geographically than females on average, although variation was large. Our results support the possibility that Eurasian lynx forms matrilineal assemblages, and comparisons with males are now required to further assess this hypothesis.