Honeybee foragers increase the use of waggle dance information when private information becomes unrewarding

Social insect foragers often have access to both social and private information about the locations of food sources. In honeybees, Apis mellifera, foragers can follow waggle dances (social information) to obtain vector information about the location of profitable food sources or they can use route memories (private information) acquired during previous foraging trips. The relative use of social information versus private information is poorly understood and currently debated. It is hypothesized that social information should be prioritized when the use of private information has a low benefit. We tested this hypothesis by training foragers to a high-quality 2 M sucrose feeder, which subsequently became unrewarding. As foragers continued to experience zero reward from their private route information they increased the time spent following waggle dances advertising an alternative food source with the same odour. A significant proportion of foragers successfully switched to the food source indicated by dances. Overall, trained foragers showed a strong attachment to the known but currently unrewarding feeder, even after repeatedly following dances advertising a profitable alternative. Successful recruits to the novel food source advertised by the waggle dances had more social information about this source in that they had followed dances for longer. Our results suggest that honeybee foragers follow a strategy that is conservative in terms of switching from one food patch to another. (C) 2011 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.