Ant colonies explore novel environments with more slower, curvier walks, particularly near the nest

Central-place foragers must learn the resource and visual landscapes around them when they are in a new environment, to facilitate efficient foraging and navigation. We investigated how the colony-level exploration strategy of Temnothorax rugatulus ants changes over time. For this study, we introduced ants to a novel environment by placing them in a foraging arena and tracking their movements over 3 days for 5 h per day, prohibiting access to the arena at other times. To test whether any changes in movement behavior are due to chemical markings, we replaced the paper floor on the third day. We found that colony-level exploration activity decreased with time, but only within a roughly 1 m radius around the nest, possibly reflecting a shift from familiarization or marking walks to searching. Individuals’ movements overall also became slightly straighter and faster across and within days. However, unlike learning walks of other ant species, T. rugatulus ants did not pause more often when facing toward the nest. Reactions to chemical markings seem to play a minor role in our observed effects, as the exploratory behavior did not reset after the floor cover had been replaced. Thus, ant colony exploration and search behaviors adapt to the familiarity of their environment by becoming more dispersive, possibly aiding in search efficiency. This must be considered in lab studies on the foraging activity and behavior of ants.