Figure 3

Population elimination by periodic release of OX3097D-Bol males. (A) The average daily egg production for each cage. Weeks 1 to 12 was the population stabilization period with 250 pupae added in the first week, and 200 pupae added to each cage per week thereafter. From week 13, 1,600 OX3097D-Bol pupae were added weekly into cages A and B. After week 13, weekly pupal return to the treatment cages was made proportional to the weekly egg production in the cage relative to the control cages. From 5 weeks after initiation of RIDL introductions, egg production in each treatment cage was consistently lower than in either control cage; the difference increased until eventual extinction of the wild-type population in both treatment cages by week 24 (12 weeks after the first RIDL release). Extinction was defined as 2 weeks of zero egg production. Egg numbers in control cages remained relatively stable. (B) Dead flies were removed from the cages weekly, and the numbers of dead females are shown. From 7 weeks after the initiation of RIDL release, increasingly fewer such females were recovered from the treatment cages than from the control cages. (C) Frequency of DsRed2 in treatment cages. Larvae selected for return were screened for presence of DsRed2 marker by fluorescence microscopy before being returned to the treatment cage (see Methods). The proportion of returning pupae carrying the OX3097D-Bol transgene reached 100% in both treatment cages by week 23 (10 weeks post-RIDL release). Olive fly females typically mate only once [21] (Figure 2B). Females start to lay eggs approximately 2 days after mating, and lay most of their eggs within the next 10 days. Egg to pupa development time was approximately 12 days. These pupae therefore indicate female mating choice of approximately 3 weeks before each measurement.