No evidence for negative frequency-dependent feeding performance in relation to personality

Abstract

An increasing number of studies report the presence of consistent individual differences in behavior and/or physiology over time and context, known as animal personality. A pivotal question in animal personality research concerns the mechanism(s) responsible for its evolution and maintenance. Negative frequency–dependent selection is considered to be one of these important mechanisms, although evidence for this is largely absent. Here, we studied whether the feeding performance of barnacle geese was negative frequency-dependent in a producer–scrounger game. We studied the feeding time of one bold or one shy individual in groups consisting of only bold or shy companions to study if the rare type in the group performs best. A previous study with this species showed that scrounging increased with shyness. Hence, we expected shy individuals to do better in the presence of bold companions due to the increased scrounging opportunity and bold individuals to do better in the presence of shy companions as there were ample opportunities to produce food. We found no evidence for negative frequency–dependent feeding success; rather, we found that, independent of their boldness score, all individuals enjoyed higher feeding success when foraging with bold than with shy companions. The higher foraging success of individuals foraging with bold companions is explained by a higher joining proportion in the presence of bold companions. Our results provide no evidence for negative frequency– dependent feeding success in barnacle geese but indicate that both bold and shy individuals can increase their foraging returns