Factors influencing Arctic brown bear annual home range sizes and limitations of home range analyses

Home range size is a basic ecological index related to individual's realized niche. Its can be influenced by body size, sex, maternal status, population density, habitat productivity, spatiotemporal variation of resources, climate, predation risk, and disturbance. estimation also greatly affected methodology sampling regime. We used Global Positioning System collar data assess what factors the annual home ranges (space use during single active season) 28 female 8 male brown bears (Ursus arctos) that denned in Brooks Range northcentral Alaska, USA, from 2014 2017. 2 methods estimate ranges, Kernel Density Estimate (KDE) dynamic Brownian Bridge Movement Model (dBBMM). Contrary expectations, we did not find larger bodied same sex had ranges. Annual (mean [standard deviation]; 504 [312] km2 3,886 [4,279] km2, using dBBMM KDE, respectively) were 3.7–9.4 times than females (135 [86] 411 [738] respectively). found greater chum salmon (Oncorhynchus keta) consumption was associated with for both sexes. In contrast, coastal bear populations consume high levels often have small suggest relatively long distance (up 100 km) between streams another key resource, denning habitat, reason positive association size. Although age our top model younger tended documented fact individuals sexes largest any could worldwide, traditional measure space (KDE). However, very large nonlocalized movements alternative method (dBBMM) delineate these provided more realistic estimates. discuss options limitations estimating recommend caution when comparing studies. With large-scale industrial infrastructure approved development this previously undeveloped region, drivers numerous management implications. Brown where primary productivity low far salmon-bearing streams, are likely move outside conservation units encounter risks as they interact human infrastructure.