Abstract
Oriental fruit fly,Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), was discovered on Tahiti Island in July 1996. Eradication programs were conducted from 1997 to 2001, but failed. From 1998 to 2006,B.dorsalis was recovered from 29 different host fruit from the five Society Islands: Tahiti, Moorea, Raiatea, Tahaa, and Huahine. Analysis of coinfestation patterns byB.dorsalis,Bactrocera tryoni (Froggatt), andBactrocera kirki (Froggatt) suggestedB.dorsalis had displaced these two species and become the most abundant fruit fly in coastal areas. To suppressB.dorsalis populations, a classical biological control program was initiated to introduce the natural enemyFopius arisanus (Sonan) (Hymenoptera: Braconidae) into French Polynesia from Hawaii. Wasps were released and established on Tahiti, Moorea, Raiatea, Tahaa, and Huahine Islands. In guava,Psidium guajava L., collections for Tahiti,F.arisanus parasitism of fruit flies was 2.1, 31.8, 37.5, and 51.9% for fruit collected for 2003, 2004, 2005 and 2006, respectively. Based on guava collections in 2002 (before releases) and 2006 (after releases), there was a subsequent decrease in numbers ofB.dorsalis,B.tryoni, andB.kirki fruit flies emerging (per kilogram of fruit) by 75.6, 79.3, and 97.9%, respectively. These increases inF.arisanus parasitism and decreases in infestation were similar for other host fruit. Establishment ofF.arisanus is the most successful example of classical biological control of fruit flies in the Pacific area outside of Hawaii and serves as a model for introduction into South America, Africa, and China where species of theB.dorsalis complex are established.