Territory size of wolves Canis lupus:: linking local (Bialowieza Primeval Forest, Poland) and Holarctic-scale patterns

Factors affecting territory size in wolves Canis lupus were studied at 2 scales, the local population (Bialowieza Primeval Forest (BPF), eastern Poland) and the geographic range of species (literature review from 14 localities in the Holarctic). Four packs of wolves were studied by radio-tracking in BPF from 1994 to 1999. The annual territories of packs (Minimum convex polygons with 95% of locations) averaged 201 km(2) (SD 63, range 116-310). Core areas of territories (50% MCP) covered from 14 to 78 km(2) (mean 35). Territory sizes and core areas both were negatively correlated to the encounter rates of ungulates (mean number of ungulates seen per unit time spent in the forest by human observers). Pack size (3-8 wolves) did not influence territory size. Home ranges of individual wolves from the same pack varied with season as well as the age, sex, and reproductive status of the wolf. Review of literature from North America and Europe (42-66 degrees N), showed that latitude and prey biomass were essential factors shaping the biogeographic variation in wolf territory size. Territories increased with latitude and declined with growing biomass of prey. The analysis showed that latitude acted partly independently of the south-north gradient in prey abundance. At similar standing crop of ungulate biomass (100 kg km(-2)), wolf territories would average 140 km(2) at 40 degrees N, 370 km(2) at 50 degrees N, and 950 km(2) at 60 degrees N. Pack size was larger at northern latitudes, but the increase did not keep pace with enlargement of territories. Within-territory density of wolves declined from 2.5-3 wolves 100 km(-2) at 40-45 degrees N to 0.7 wolves 100 km(-2) at 60 degrees N. Our analyses documented similarities regarding the role of prey resources in shaping wolf territoriality at the different scales. Furthermore, a macroecological approach revealed additional factors affecting wolf territory size that were not emergent from knowledge of local population.