Following the discovery of an introduced little fire ant population on Tahiti in October 2004, an inventory has been launched to map the infestation on this island, but also on the adjacent island of Moorea. This effort leads to an update of the ant fauna of both islands.

Forty four ant species are now recorded from these sister islands. These insular ant communities this fauna appear heavily dominated by introduced species: there is no endemic ants and only nine species may be considered autochtonous ones (Hypoponera confinis, Oligomyrmex corniger (=Oligomyrmex tahitiensis), Pheidole oceanica; Pheidole sexspinosa; Pheidole umbonata, Platythyrea parallela; Ponera swezeyi; Rogeria sublevinodis; Strumigenys mumfordi (=Smithistruma mumfordi)). Among the introduced species, four major invasive ants are recorded: Anoplolepis gracilipes, Pheidole megacephala, Solenopsis geminata and Wasmannia auropuncta.

From a conservation perspective, in the context of French Polynesia, which is recognised as one of the 25 world major biodiversity hotspots, we consider these species as major threats that would imperil biodiversity, especially if they spread further in altitude. Among them, the recent discovery of W. auropunctata is especially a major concern, according to its well-known biodiversity disruption abilities. To date, little fire ants appear restricted to Tahiti, where 15 infestations have been recorded, covering 250 ha.

All these plots are under an eradication plan with Amdro® treatment since July 2005.