title: Carbon dioxide narcosis modifies the patch leaving decision of foraging parasitoids.
abstract: Gleaning information is a way for foragers to adjust their behavior in order to maximize their fitness. Information decreases the uncertainty about the environment and could help foragers to accurately estimate environmental characteristics. In a patchy resource, information sampled during previous patch visits is efficient only if it is retained in the memory and retrieved upon arrival in a new patch. In this study, we tested whether the braconid Asobara tabida, a parasitoid of Drosophila larvae, retains information gleaned on patch quality in the memory and adjusts its foraging behavior accordingly. Females were anesthetized with CO(2) after leaving a first patch containing a different number of hosts and were allowed to visit a second patch containing only kairomones. CO(2) is known to erase unconsolidated information from the memory. We show that in the absence of a short CO(2) narcosis, females responded according to their previous experience, whereas anesthetized females did not. The anesthetized females stayed a given time in the second patch irrespective of what they encountered before. CO(2) narcosis had no effect on the residence time of the non-experienced females in a patch containing hosts or only kairomones in comparison with the non-anesthetized females that had a previous foraging experience. We conclude that CO(2) narcosis erases the effect of the previous patch quality, perhaps due to a memory disruption. Direct information processing is likely to be involved in parasitoid decision making through retention of the information on the previous patch quality into a CO(2) sensitive memory.
authors: Université de Rennes, Campus de Beaulieu, Rennes Cedex, France. philippe.louapre@mail-univscience.com
authors: Philippe
authors: P
authors: Louâpre
authors: Jean-Sébastien
authors: JS
authors: Pierre
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000494:pharmacology; D003657:Decision Making / Q000187:drug effects; D005260:Female; D008568:Memory / Q000187:drug effects; D011235:Predatory Behavior / Q000187:drug effects*; D014863:Wasps / Q000187:drug effects / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide