'O neighbour, where art thou?' : spatial and social dynamics in wolverine and lynx, from individual space use to population distribution

• The organisation of individuals in space and time influences population structure and dynamics, and is important for our understanding of animal ecology. The aim of this thesis is to gain an increased understanding of the mechanisms driving the abundance and distribution of solitary carnivores, from individual space use to population-level distribution. I used individual-level spatial and demographic data from Eurasian lynx (Lynx lynx) and wolverines (Gulo gulo), collected over more than 20 years in multiple areas within Scandinavia, to assess space use determinants and link territorial dynamics to dispersal patterns. For lynx, female total home range size declined as roe deer and lynx density increased. Male total home range size also declined with higher lynx density, while prey only became important for determining the size of more intensively used areas within the home range. There is also a positive effect of roe deer abundance on lynx survival in south-central Sweden. Roe deer is a predictable prey source compared to migrating reindeer, the main prey for lynx in northern Sweden. I found that home range overlap between neighbouring lynx increased with their relatedness (mother-daughter) for females in northern Sweden, but not for males nor females in the south. This finding suggests inclusive fitness benefits of sharing an unpredictable and highly seasonal food source with known relatives. The wolverine study population was characterized by a stable distribution of resident individuals with high territorial fidelity. When a territory became vacant in the study area, it was almost exclusively reoccupied by a female from the surrounding area. The availability of a young female’s natal territory substantially increased the probability of her establishing in the study area. Furthermore, the probability of a young female leaving the study area increased as the number of available territories decreased. This finding suggests that the study population is saturated, with limited room for dispersers to establish, which suggests that emigration to surrounding areas is related to survival of resident females. Wolverines in Sweden have expanded into boreal forests south and east of alpine areas. However, the recolonised areas with limited snow cover remain largely unmonitored. Most females gave birth in natal dens in mid-February, and rarely moved their cubs between den sites for the first two months, while lactating and while prey availability was low. After weaning, den shifting over longer distances increased, matching the seasonal increase in prey availability. Increased knowledge of spatial and social dynamics can give insights into how these populations are influenced by human activity, as well as the outcome of management actions.

Subject headings

NATURVETENSKAP  -- Biologi -- Ekologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Ecology (hsv//eng)

Publication and Content Type

vet (subject category)

dok (subject category)