Age and experience influence patch assessment for oviposition by an insect predator

Abstract

Abstract. 1. Dynamic models of optimal foraging predict that an animal's decision to accept or reject a patch depends not only on the environment and patch quality, but also on its internal state. Previous experiments have shown that the two‐spot ladybird beetle, Adalia bipunctata (L.), is reluctant to lay eggs in a patch of prey contaminated by the oviposition‐deterring pheromone produced by conspecific larvae. 2. An experiment was conducted to test whether the internal state of an A. bipunctata female affects its oviposition response to oviposition‐deterring pheromone. Firstly, the oviposition response to oviposition‐deterring pheromone of young and old females was compared. Secondly, the oviposition response to oviposition‐deterring pheromone of females previously exposed continuously to oviposition‐deterring pheromone was compared with that of females of the same age but with no previous experience of oviposition‐deterring pheromone. 3. Old females and females with previous experience of oviposition‐deterring pheromone were less reluctant to lay eggs in the presence of oviposition‐deterring pheromone than young and naive females. These results are consistent with the predictions of optimal foraging theory.