Wolverines use spatial memory to plan efficient routes through rugged terrain.

Abstract

Background: To navigate, animals balance nearby perceptual cues, random search, and memory. Isolating the role of memory, however, remains difficult.

Methods: Here, we use a mechanistic movement model to do so, simulating animals responding solely to local perceptual cues (i.e., lacking memory) and comparing their paths with actual routes taken. By comparing route efficiency, we evaluate whether actual routes incorporate knowledge beyond the perceptual range (i.e., spatial memory).

Results: We show that wolverines (Gulo gulo) employ spatial memory to plan routes through a rugged, mountainous landscape. Furthermore, we find that wolverines most commonly plan routes to destinations 5.3-9.8 km ahead. We estimate that route-planning saves wolverines, on average, 19.3 kcal per 135 min of movement.

Conclusions: Our findings provide a template for evaluating how free-living animals recall the world beyond their perceptual range, offer a window into the cognitive mechanics underpinning navigation for this species, and support adding wolverines to the primate-dominated list of species with complex spatial memory.