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Age and experience influence patch assessment for oviposition by an insect predator |
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| Authors: | Bruno Frechette Anthony F. G. Dixon Claude Alauzet Jean-Louis Hemptinne |
| Affiliation: | UniversitéPaul Sabatier, Laboratoire d'écologie terrestre, Toulouse, France,;School of Biological Sciences, University of East Anglia, Norwich, U.K. and;Ecole Nationale de Formation Agronomique, Laboratoire d'Agro-écologie, Auzeville, France |
| 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. |
| Keywords: | Adalia bipunctata Coccinellidae dynamic models larval tracks optimal foraging oviposition-deterring pheromone state dependent |