Spotted-wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive species that has impacts worldwide. Current monitoring methods and decision-making protocols are unreliable indicators of D. suzukii population and propensity to infest a crop. The aim of this research was to develop behavior-based tools that would lead to improved management of D. suzukii populations in Michigan cherry. The commercial Scentry® lure provided higher D. suzukii attractiveness than other commercially available lures. Sticky panels tested with a variety of colors and patterns showed that most D. suzukii are captured on a green panel or a light-colored panel with a dark contrasting sphere in the center, as well as panel traps with a large trap surface are. Studies aimed at understanding the relationships between fruit development and D. suzukii infestation revealed that over all the varieties of sweet and tart cherries tested, softer, riper fruit were more susceptible to infestation than unripe fruit. There were strong positive relationships between D. suzukii larval infestation and the change in color and the change in the amount of force required to puncture the skin of the cherry fruit. There also was a good relationship between Growing Degree Days (base 4°C) post bloom and larval infestation, with fruit at a low risk of infestation by D. suzukii prior to about 600 GDD's. This research provides information on creating a risk of infestation model that uses fruit ripeness stage based on Growing Degree Days, combined with effective monitoring tools, to provide options for improved decision-making in the management of D. suzukii.
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