Female dispersal and isolation-by-distance of Nasonia vitripennis populations in a local mate competition context

Dispersal behavior directly influences the level of inbreeding, but the effect of inbreeding avoidance on dispersal is less well studied. The parasitoid wasp Nasonia vitripennis (Walker) (Hymenoptera: Chalcidoidea: Pteromalidae) is known to mate exclusively on the natal patch, and females are the only dispersing sex. A previous study has shown that foundresses on a patch are typically unrelated, implying that females disperse for a considerable distance from their natal patch after mating. We investigated dispersal of N. vitripennis on two scales. On a local scale we used a mark-release-recapture experiment, and on the larger scale we investigated isolation by distance using a population genetic approach. We found that N. vitripennis females are long-distance dispersers, capable of covering at least 2 km in 48 h. Populations within a range of 100 km showed no substructure, but larger distances or major geographical barriers restricted gene flow and led to significant population structure. The results provide a basis for future research on dispersal of parasitoids and are discussed in the context of dispersal abilities and inbreeding avoidance in Nasonia .