Submitted to: Hawaiian Entomological Society Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2013
Publication Date: 12/1/2013
Citation: Leblanc, L., Vargas, R.I., Putoa, R. 2013. From eradication to containment: invasion of French Polynesia by Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) and releases of two natural enemies: a 17-year case study. Hawaiian Entomological Society Proceedings. 45:31-43. Interpretive Summary: This paper describes a the invasion of French Polynesia by the Oriental Fruit Fly (OFF) and subsequent efforts to control it via biological control with a variety of parasitoid wasps. Analysis of the effect of biological control show that there was successful control of OFF on Tahiti Island.
Technical Abstract: Oriental fruit fly, Bactrocera dorsalis (Hendel), was discovered on Tahiti Island, French Polynesia, in 1996. Two other economically important Bactrocera species were previously established: B. kirki (Froggatt) in 1928, and B. tryoni (Froggatt), Queensland fruit fly, in 1970. This situation provided a unique opportunity to investigate interspecific competition and displacement among three different invasive Bactrocera species. In addition two natural enemies were released against B. dorsalis. In 2002 Fopius arisanus (Sonan), was released and established. By 2009 mean (± SD) F. arisanus parasitism for fruit flies infesting common guava (Psidium guajava), Polynesian chestnut (Inocarpus fagifer), and tropical almond (Terminalia catappa) fruits on Tahiti Island was 64.8 ± 2.0%. A second parasitoid, Diachasmimorpha longicaudata (Ashmead), was released and established in 2008. Although widespread, parasitism rates have not been higher than 10%. Analysis of co-infestation patterns (1998-2009) of B. dorsalis, B. tryoni, and B. kirki, suggest B. dorsalis is now the most abundant species in many common host fruits (P. guajava, T. catappa, I. fagifer, and M. indica). Establishment of F. arisanus is the most successful example of classical biological control of fruit flies in the Pacific outside of Hawaii. Numbers of fruit flies have been reduced by 75%.