Time-place learning and leader-follower relationships in Arctic charr Salvelinus alpinus

Feeding activity from a larger refuge site into two visually separated feeding sites with temporally restricted food availability, one in the morning and one in the evening were studied in duplicate groups of Arctic charr (Salvelinus alpinus L.). A pit-tag system enabled continuous monitoring of individual movements between the sites. Both groups synchronised their diel pattern of visit activity to the two feeding sites when food was available. One group showed a significant anticipatory visit activity into both feeding sites during the hours before the feed was available, suggesting a time and place learning of resource availability. The anticipatory activity of the other group was, however, less pronounced and only occurred into one of the feeding sites. Individual S. alpinus entered the feeding sites independently and no obvious patterns of leaders and followers were identified. All S. alpinus gained mass and moved between a refuge and the feeding sites. Different strategies of how individual S. alpinus utilized the feeding sites were not correlated with growth.