Pest control officers in French Polynesia say the killer wasps they set loose in order to control an outbreak of a destructive fly, have largely done the job.
The French Polynesian rural development service and the University of Berkeley launched an operation in May to wipe out the Glassy Winged Sharpshooter, which sucks sap from trees and emits toxic urin.
The service says between 90 to 100 per cent of the pests have gone from 27 sites where they released killer wasps.
The wasps can now be found at the summit of Tahiti's mountains, 1500 metres above sea level.
Specialists say the problem is now to find a balance between the populations of the two species.
The Glassy Winged Sharpshooter arrived in French Polynesia on pot plants from California in the 1990s.