Every northern gardener can tell you about Green Tree Ants. "They are pesky and numerous and get all over you when you try to garden". So true but when you look into them in a bit of detail, they are marvels of organisation.
The Green Tree Ant, Oecophylla smaragdina, in the same genus as the Weaver Ants of Africa. Our species is widespread in the tropics. Its geographical range includes northern Australia and much of tropical Asia.
We seldom see GTA's in the rainforest because they are ants of the "edge" or of disturbed or open areas. You can usually find them on the vegetation of recently cleared areas or under power-lines where the vegetation is regularly cut and the habitat is more open. These ants are principally predators. They feed on other insects or whatever protein they can manage. I heard recently of an observation of hundreds of ants moving a small road-killed python up a tree to their nest where it would be dissembled and eaten.
When I consulted the "Ant Bible" I found numerous references to GTA's but nothing on their prey-capturing techniques.
This book is well worth having. It is 732 pages of fascinating information about the world of ants.
The GTA's have a cadre of commensals that live with them and serve a variety of purposes. Butterfly caterpillars live within the nests affording them protection from predators and parasites. Their excretions provide the ants with sugars they need in their diets. The ants also "farm" in the sense that they promote and cultivate certain bugs like aphids and scales that also provide them with sugars for their diet. The ants no only protect their "cattle" from predators but they move them to better sites if they find them. So having GTA's in the garden because they consume pest insects is not always the case.
GTA's seem to be seasonal in our rainforest garden. We are in the midst of a very dry Dry Season and the forest has opened up a bit. Thus the ants. I suspect as the rains approach and the vegetation becomes a bit more dense, the GTA's will disappear and other more adapted rainforest species will take over.
1st February 2015 Kingfisher Park Birdwatchers Lodge
13 hours ago