Hymenopteran parasitoids are attracted by sex pheromones of cerambycid beetles

Beetles in the family Cerambycidae often emit long-range, sex pheromones to facilitate mate-location. Several species of parasitoids have been shown to 'eavesdrop' on olfactory cues emitted by potential hosts. Orienting towards the sex pheromones of potential hosts may be a reliable and efficient way to locate an opportunity to oviposit. Our objective was to determine the identities and abundances of the species of parasitoids that are attracted to the sex pheromones of species of cerambycids. We hypothesized that there would be a greater response by parasitoids to lures that attract many species of cerambycids, relative to lures that attract fewer species of cerambycids. We surveyed the communities of parasitoids at Allerton Park in central Illinois every two weeks from 9 June - 4 September 2014. Clear sticky traps were oriented in a cross-vane at a height of 1.5 m. Six traps were placed at least 10 m apart, along transects, and rotated every other day. Cylinders of 1 cm hardware cloth were hung over sticky traps to exclude bird and mammal visitors. Traps were baited singly with one of the following: (anti) 2,3-hexanediol, (syn) 2,3-hexanediol, (anti) 2,3-octanediol, (syn) 2,3-octanediol, 3-hydroxyhexan-2-one, or our solvent control, isopropyl alcohol. Lures and traps were replaced every two weeks. Results from our study will contribute to our knowledge of the parasitoid communities in central Illinois. Additionally, our study will help us better understand how parasitoids locate hosts. This work is ongoing.