Foraging bumblebees do not rate social information above personal experience

Abstract

Foraging animals can acquire new information about food sources either individually or socially, but they can also opt to rely on information that they have already acquired, termed “personal information”. Although social information can provide an adaptive shortcut to new resources, recent theory predicts that investing too much time in acquiring new information can be detrimental. Here, we investigate whether foraging bumblebees (Bombus terrestris) strategically prioritize personal information unless there is evidence of environmental change. All bees in our study had personal information that one species of artificial flower was rewarding, and bees in the scent group then experienced social information about an alternative-scented species inside the nest, while a control group did not. On their next foraging bout, bees in both groups overwhelmingly used personal information when deciding where to forage. When bees subsequently learnt that the rewards offered by their preferred species had dwindled, bees that had social information were no quicker to abandon their personal information than control bees, but once they had sampled the alternative flowers, they showed greater commitment to that species than control bees. Thus, we found no evidence that social information is particularly important when personal information fails to produce rewards (a “copy when established behaviour is unproductive” strategy). Instead, bees used social information specifically to complement personal information.