Impact of the Little Fire Ant, Wasmannia auropunctata, on Native Forest Ants in Gabon1

The Neotropical little fire ant, Wasmannia auropunctata, is notorious for its negative impacts on the native biota of tropical islands, such as the Galapagos and New Caledonia, where it has been introduced.Here, I evaluate the impact of exoticW. auropunctata populations on continental Africa. I surveyed ants at nine sites in Lop´ National Park in Gabon, Central Africa, and found a highly significant correlation between ant diversity and length of infestation byW. auropunctata.Ifoundmany e more native ant species present in areas not infested with W. auropunctata (39.0 ± 4.6) compared with areas infested by W. auropunctata for approximately 5–10 yr (7.0 ± 6.2 and 1.7 ± 1.2, respectively). In infested areas, W. auropunctata made up the bulk of specimens collected in every plot. This study demonstrates that the threat posed by W. auropunctata to biodiversity is as serious in continental ecosystems as it is in the more fragile island ecosystems of previous studies. Introductions near waterways are particularly devastating: in Lopé, the infested territory is most extensive along waterways and occurs in a pattern that strongly suggest moving water facilitates colonization.