Drosophila suzukii is an invasive pest that has disrupted existing IPM strategies of cherry and small fruit industries. Shortly after its introduction, D. suzukii established across the United States, by exploiting non-crop habitats and infesting thin-skinned fruit monocultures. Using its serrated ovipositor, females can infest wild and cultivated fruit throughout the growing season. In Michigan, native predators are insufficient for suppressing D. suzukii populations, creating a dependency on chemical sprays. However, populations residing in wild refugia adjacent to agricultural fields are left untreated and require alternative methods. Drosophila suzukii natural enemies within its native range were investigated, in search for a classical biocontrol agent. Ganaspis kimorum (formerly G. brasiliensis) was found to be an exclusive larval parasitoid of D. suzukii and a potential self-regulating method of targeting pest populations. I investigated the ability of G. kimorum to overwinter in Michigan fields, near locations of release and the abiotic factors that influence its success. Snow cover and number of days where wasps were exposed to ground temperatures below freezing influenced survival. I also evaluated G. kimorum dispersal capability and host finding behavior using baited traps just after harvest; however, no G. kimorum was detected in sentinel traps. Specimens of this species were found in fruit surveys conducted at release sites, along with adventive populations of Leptopilina japonica. This is the first detection of G. kimorum emerging from established D. suzukii in Michigan agricultural fields. These findings will be influential in determining the future success of establishing G. kimorum as a biocontrol agent against D. suzukii populations.
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