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Many animals use visual cues such as object shape, color and motion to detect and pursue conspecific mates. Contrast is another possibly informative visual cue, but has not been studied in great detail. In this study, we presented male Drosophila melanogaster with small, fly-sized, moving objects painted either black, white or gray to test whether they use contrast cues to identify mates. We found that males frequently chased gray objects and rarely chased white or black objects. Although males started chasing black objects as often as gray objects, the resulting chases were much shorter. To test whether the attraction to gray objects was mediated via contrast, we fabricated black and gray behavioral chambers. However, wild-type males almost never chased any objects in these darkly colored chambers. To circumvent this limitation, we increased baseline levels of chasing by thermogenetically activating P1 …