Analysis of episodic spatio-temporal memory patterns in brown bears using animal movement modelling

Background/Question/Methods

Animal movement modelling provides unique insight about how animals perceive their landscape and how this perception influences their space use. When coupled with data describing an animal’s environment, it is possible to fit statistical models to location data to describe how spatial memory informs movement. We developed a new class of model, which accounts for how memory of the seasonal or ephemeral qualities of an animal’s environment affects its movement patterns. The model accounts for resource selection in the present time as well as long-distance navigations to previously visited locations within an animal's home range.

Results/Conclusions

We applied our modelling framework to a population of brown bears (Ursus arctos) in the Canadian Arctic, testing four alternate hypotheses about spatial memory in brown bears and finding substantial individual variation in how brown bears used memory. We found that 71% (15 of 21) of the bears used complex, time-dependent spatial memory to inform their movement decisions. Amid this individual variation, the most common behavioral pattern observed in the bears was highlighted by recursions to areas visited approximately one year earlier. These results, coupled with existing knowledge on individual variation in the population, highlight the diversity of foraging strategies for Arctic brown bears while also displaying the kind of inferences that can be drawn from this new class of movement models.