Mating competitiveness of irradiated flies for screwworm fly eradication campaigns

Should the screwworm fly invade Australia, the sterile insect technique (as used successfully overseas) is currently the only feasible method of eradication. Used in conjunction with chemical control methods, it relies on large numbers of factory-reared, sterilized males competing successfully with wild males for the wild females. However, laboratory and field studies have shown that the processes of mass rearing, irradiation and distribution seriously impair the competitiveness of the sterilized flies. This study collates and analyses the relatively sparse information on the relative mating competitiveness of sterilized screwworm flies, from both controlled experiments and large-scale field studies. A population dynamics example then demonstrates that competitiveness will be a key parameter in the effectiveness and economic feasibility of any future eradication campaign.