Patch time allocation and resource exploitation in aphid primary parasitoids and hyperparasitoids searching simultaneously within aphid colonies

The foraging behaviour of the aphidiid wasps Lysiphlebus cardui and Aphidius funebris was analysed when a single hyperparasitoid female (Alloxysta brevis, Alloxysta victrix or Dendrocerus carpenteri) was searching simultaneously in the same aphid colony. Patch residence times and oviposition numbers of L. cardui and A. funebris searching in colonies with hyperparasitoids were not significantly different from those for aphidiid females searching in colonies without hyperparasitoids. Furthermore, the oviposition rate after the first contact with a hyperparasitoid female did not differ significantly from the control, both in L. cardui and A. funebris. We conclude that the presence of hyperparasitoid females does not directly influence the foraging behaviour of the aphidiid females. 1995 Blackwell Verlag GmbH