Contributions to the foraging ecology of house flies, Musca domestica L.

Attract-and-kill tactics for control of house flies (Musca domestica) often use foraging cues as attractants. To investigate foraging resources for indoor attraction of house flies, I tested the response of flies to various human foods and a floral resource. In two-choice laboratory bioassays, only dandelion flowers and dandelion honey attracted flies. Analytical attempts to capture the essential semiochemicals from these resources failed, highlighting the need to develop alternative approaches. Another potentially effective foraging cue is the “fly factor”, the phenomenon that food currently or previously fed on by flies attracts more flies than the same type of food kept inaccessible to flies. In two-choice laboratory bioassays, I demonstrate that the fly factor exists in house flies. Of the mechanisms tested potentially causing the fly factor, only fly feces and regurgitate attract flies. Attraction of flies to fly feces and regurgitate indicates that flies sense airborne semiochemicals emanating from these sources.