The Ecology of Fruit Flies

The dominant feature of fruit fly research over the past decade has been a considerable preoccupation with projects related to the suppression or eradication of populations by the release of sterile individuals. The success of the eradication campaigns against the screwworm fly, Cochliomyia hom­ nivorax, (16), followed by further successes against the melon fiy, Dacus cucurbitae, and the Oriental fruit fiy, Dacus dorsalis, by Steiner and his associates in the Mariana islands (147, 149), has engendered considerable enthusiasm for the sterile male technique among those concerned with the control of fruit flies. Entomologists concerned with many other groups of insects are turning more and more toward pest (37, 122) or integrated proce­ dures of control based on solid ecological foundations. These methods aim, not at the complete destruction of the pest population, but at its reduction to a low mean level of abundance, so that its fluctuations seldom or never carry it above its economic threshold. But for fruit flies, particularly in situ­ ations where fruit is grown for export to uninfested areas, or where con­ sumers demand a perfect product, the economic threshold may often be near zero, and the strong preference for eradicative rather than management procedures is readily understandable. '