Composite Brownian walks best explain the movement patterns of Asian black bears, irrespective of sex, seasonality, and food availability

Abstract

Large solitary carnivores need to correspond to spatial and temporal variations in food resources, and therefore are expected to change their movement strategies seasonally and annually. Movement strategy of an animal is also mediated by internal factors such as sex. We investigate movement strategy of Asian black bears (Ursus thibetanus) in two biological periods (mating and hyperphagia periods), by fitting random walk models including Brownian walks (BWs), Lévy walks (LWs), and composite Brownian walks (CBWs). We explored the best random walk models approximating the movement paths of 59 trajectories performed by 29 Asian black bears, obtained in years with different food availability. The results strongly supported the occurrence of CBW patterns over scale‐free LW patterns for their movements. We found some differences in composition of the best CBW models between mating and hyperphagia periods, though no distinctive differences were found among the best models regarding sex and food availability. Our findings demonstrated that the CBW is the best model to describe the movement of the Asian black bears among the random walk models tested, and indicate the importance of understanding multiple modes of their activity or movement.