Territoriality and movement dynamics of Scandinavian wolves (Canis lupus)

Sammanfattning

Territorial behaviour in wolves (Canis lupus) plays a central role in shaping social dynamics, resource access, and population structure. Although wolf packs are typically territorial, spatial overlap between neighbouring territories does occur. Understanding the drivers of these overlaps provides insight into wolf social organisation, resource competition, inter-pack conflict risk, and individual movement between packs, factors that collectively influence broader population dynamics. This study investigates spatial overlap among neighbouring wolf territories in Scandinavia using GPS collar data, genetic relatedness, and spatial modelling. I applied Generalized Additive Models (GAMs) to model the size of spatial overlap (km²) between territorial pairs as a function of several covariates: (1) normalized difference in territory size, (2) dyadic social status (scent-marking pair vs. family group combinations), (3) genetic relatedness between alpha males and between alpha females, and (4) time since territory establishment. These covariates were selected based on ecological relevance and were derived from long-term monitoring data and pedigree records. Spatial overlap was best predicted by territory size differences, dyadic social status, and female genetic relatedness. Overlap increased with greater disparity in territory size and was higher between scent-marking pairs compared to family groups. Female relatedness showed a non-linear effect; overlap increased with initial relatedness but declined beyond a threshold. Male relatedness had no notable effect. Complementary Generalized Linear Mixed Models (GLMMs) were used to assess how wolves used different territorial zones (core, peripheral, overlap). These models revealed that wolves generally spent less time in overlap zones, with scent-marking pairs using these areas more than family groups. Additionally, territory age (defined as years since establishment) was negatively associated with overlap use, suggesting that older territories exhibit greater spatial stability and reduced inter-pack intrusion. Together, these findings highlight the importance of social structure, territorial history, and genetic relationships in shaping spatial interactions among wolf packs. Understanding these drivers is essential for interpreting wolf space use in multi-use landscapes and has consequences for the management including monitoring of the population.