Group foraging in wild brown hares: effects of resource distribution and social status

Abstract

Wild brown hares ( Lepus europaeus), though normally comparatively solitary, have the capacity to adjust their behaviour such that they can benefit when foraging in groups. They are able to allocate more time to feeding and have an increased corporate vigilance as group size increases. However, these benefits are conditional upon the food distribution. When food is spaced, all individuals benefit. When it is clumped into a small defendable patch, dominant hares attempt to monopolize the resource. They can successfully exclude subordinates when group size is small but, as group size increases, they must devote more time to defending the patch. Therefore, dominants spend less time feeding with increasing group size, while subordinates spend more, since they have more opportunity to feed while the dominant hare is off chasing other individuals. As a consequence, when more than two hares are present, all individuals do less well when food is clumped than when it is spaced.