Hello David;

     There are at least two issues to consider. The first is that the invasion of this ant into Tahiti was achieved by one or more colonies being imported in commerce. Potted plants, produce, damp packing material and the like are the likely vehicles. The eradication must protect against this kind of movement within, and into the region.

     The second issue...how far individuals disperse is also is complicated. An individual worker cannot expand the geographical range of the species and they can probably only move a few meters away from the nest . It is fertile queens that can expand the range of the species. I am aware of one example of a Solenopsis invicta queen flying 6 km over water. Other, genetic studies suggest that flying queens disperse only a few hundred meters from the natal nest. Species where the queens disperse on foot travel even less.

     I hope that this is a start for you,

Best regards, Jim des Lauriers

With invasive ants, it is common to observe seasonal variation in the spatial extent of a colony: they may not move far from the nest, but they can extend the nest to get closer to where they want to go. This should be taken into account when deciding of new treatment strategies.

For example in the Argentine ants:

Heller, N. E., & Gordon, D. M. (2006). Seasonal spatial dynamics and causes of nest movement in colonies of the invasive Argentine ant (Linepithema humile). Ecological Entomology, 31(5), 499-510.