Hurrying Foragers Fail to Choose the Best Prey Item: Prey Choice in Paper Wasps Depredating Conspecific Nests

Abstract

Animals frequently face situations where they must choose one prey item from a set of options. Animals are often considered to be able to choose the best prey item from multiple alternatives. However, time may be required to make accurate decisions, and under natural conditions, time is usually limited. Here, we examined whether animals fail to choose the most profitable prey item under time-limited conditions. A queen (foundress) of a paper wasp Polistes chinensis antennalis starts a colony in spring and maintains the nest alone until the emergence of workers. At the stage, the foundress often depredates larvae in other conspecific nests. The intruder needs to finish choosing and extracting a single larva during the absence of the owner from the nest. Intruders preferred the fifth-instar larvae, which are the largest and the most profitable prey among larvae. When the time spent in choosing was long, intruders were able to choose the fifth-instar larvae with a higher probability. However, when the time spent in choosing was short, intruders sampled only a small fraction of larvae in a nest, and the probability of choosing the fifth-instar larvae decreased. Furthermore, we found that intruders decreased the time spent in choosing under higher time constraints. These results suggest that under time-limited conditions, intruders occasionally failed to choose the most profitable prey item because of incomplete information on the availability of options. These results also suggest a trade-off between speed and accuracy of choosing the best item from a set of options.