Interaction betweenChrysomya rufifaciesandCochliomyia macellaria(Diptera: Calliphoridae): the possible consequences of an invasion

Four Old World blow flies (Diptera: Calliphoridae),Chrysomya albiceps(Wiedemann), C.putoriaWiedemann, C.megacephala(Fabricius), and C.rufifacies(Macquart), have recently invaded the New World. The interaction ofChrysomya rufifacies(Macquart) with native carrion flies in Texas, USA, was investigated by reducing oviposition by the invader on rabbit carcasses outdoors. These carcasses produced significantly moreCochliomyia macellaria(Fabricius) adults compared to carcasses on which the invader was not reduced. The results suggest that C.macellariapopulations will decline where the two species co-occur. They also support the hypothesis that the carrion community is saturated with species, and provide a mechanism for the possible elimination ofLucilia caesar(Linnaeus) in Madeira and the reduction of C.macellariain South America byChrysomya albiceps(Wiedemann).