Competitive interactions and foraging path selection in bumblebees

Inflorescence richness and density did not affect the magnitude or variation in magnitude of the turning angles between inflorescences in the paths of foraging bumblebees. The pooled data indicated that bumblebees tended to move straight through the Vicia patch regardless of raceme density. The angular distributions from the field data were similar to those derived from a computer model in which consumers just visited the nearest inflorescences provided that they revisited few flowers. These results imply that the foraging paths of bumblebees may be determined, in part, by a tendency to visit nearest inflorescences. The distribution of turning angles from individual rather than pooled data, however, suggest that active selection of inflorescences with between two and six flowers may also play a role in determining the foraging path. I found no evidence for area-restricted foraging. This may be due to the heterogeneity of the natural resource patches.