Light Intensity and Temperature as Factors Limiting the Mating of the Oriental Fruit Fly

Abstract

In the initial field and laboratory studies of the oriental fruit fly, Dacus dor salts Hendel, in Hawaii, it was observed that this insect mated only during the twilight period when the evening temperature was above 60° F. Caged flies in the laboratory exhibited a sexual behavior comparable with that reported by Back and Pemberton (1917) for the melon fly, Dacus cucurbitae Coq. As twilight approached, the flies became excited and produced a characteristic high-pitched buzzing sound, followed by copulation, the flies remaining in copula for 2 to 12 hours. A series of experiments was set up to determine what factors inherent in twilight conditions are responsible for this behavior, and to evaluate the limitations imposed on the reproductive potential of this fly by cool temperatures at the time mating normally occurs.