Leaf Cutting Ant Forum

One of the consequences of having so many colonies in such close proximity to each other in my ant room is that you get to see phenomena which otherwise would be difficult or impossible to observe in normal circumstances.
The most amazing thing happened a few days ago. One of the big colonies happened to bridge the water over a fallen leaf at the same time as a queenless 'colony' I was building up pending the addition of a new queen was sitting on a shelf in a box. The large colony discovered this box of fungus, ants and brood and immediately started to raid. They removed fungus ants and brood and a line developed back to the big nest. However something very strange happened after a while. The raided ants which were carried back to the big colony immediately picked up some fungus and brood and started to carry this back to their 'nest'. After a while there was two way traffic of material being carried between the nests. Over the next 12 hours this continued but because there were more ants coming from the big colony to the small colony and removing material back to the large nest, gradually the smaller nest began to disappear. Eventually everything was removed to the large colony.
This threw up some very interesting ideas. Firstly because Leaf Cutters are not carnivorous they cannot harvest the resources of another colony by eating them like some other species. So they remove and use the other colonies resources in their own colony. This can be fungus, brood or even ants.
Secondly there does not seem to ever be a fight. When two colonies encounter each other there seems to be a signal which lets the smaller colony know it is outnumbered and as a result, apart from some skirmishes over the queen etc, most raids proceed with overwhelming numbers and little resistance.
But the two way traffic I have observed several times seems to me to be a trial of strength. Moving resources back to each colony is almost analogous to a tug of war ending when the better resourced colony, by the product of more numbers, eventually moves more material than they lose and the smaller colony ceases to exist through a process of degradation. I have checked the literature and there is nothing about this published. Two way raiding would be an extremely elegant method of settling disputes, almost a competition which results in once colony winning and benefiting from the addition of a mass of new material.

Great post! So the only casualty would be perhaps the queen if a smaller colony if it had a queen. I guess you are in a unique position to observe such happening. How could you get credited with discovering this behaviour?
What do you do again when adding ants and fungus to another colony? I remember reading that you did something to ensure the safety of the queen. Say you wanted to make a two queen Acromyrmex

Because Acromyrmex queens regularly cooperate with each other in founding a colony, it is easy to combine queens and colonies. They generally accept additions with little trouble. Dont think I could create a 2 queen Atta though. With Atta the trick is to remove the larger workers. If you are introducing a queen to a colony you need to get her smelling of the colony first so you get some of the recipient fungus and stir the queen around in it for a while. Then add some ants and keep going for a day or so adding more until you can just tip the tubs contents into the queenless nest.

The behaviour you are describing Andrew is similar to what I am observing in our colony, but it's a 'within colony' battle. Back and forth with fungus, brood etc. Do you think I now have two queens here? I have found new, live queens and males in two, separate tanks, or I suppose they could have just walked there.

Does the smaller colony then accept this defeat and end up being a part of the larger colony? I wouldn't have thought they would be killed, would they?

If we are talking Acros then the story is very different. The raiders will take everything from the nest but I havent seen them take the queen. So many times, when Ive got there too late, the raid is finished and all that is left in the raided tub is an Acromyrmex queen. If she is undamaged, as is usually the case, then I can remove fungus and ants from the raiding colony and simply put it back with the queen, no damage done. Interestingly, if I find a raid in progress because there is a bridge formed over the water to the nest, and it is overrun with raiding ants, if I remove the bridge then the raiding ants simply move into the raided colony and become contributing members of that society. I think this behaviour is odd. It doesnt seem to fit with any genetic strategy. The chances are that this new colony is unrelated to the raiding colony so why would displaced workers become assimilated into this willingly. Also, if this was a carnivorous species, such behaviour would more likely be a precursor to slave making. But in Leaf Cutters you can effectively demonstrate slave making at the adult ant level where there is no necessitiy to hatch brood that then behaves like members of the raiding nest. So odd behaviour. In Atta they pretty much always damage the queen. Normally the antennae and the legs are removed but they dont kill her. She always dies though.

Really interesting. Thanks for sharing

So when you see this happen again and you are left with an odd queen,,,,I'm yer man

RichardP wrote:Really interesting. Thanks for sharing

RichardP, as I live and breathe!! How the dam devil are you!

Andyj wrote:So when you see this happen again and you are left with an odd queen,,,,I'm yer man

mmmmmhhhh! Cant help thinking you are not entering into the spirit of this thread. Like a vampire bat lurking in the shadows, waiting for an opportunity to sneak in and suck!

Acromyrmexbob wrote:

Andyj wrote:So when you see this happen again and you are left with an odd queen,,,,I'm yer man

mmmmmhhhh! Cant help thinking you are not entering into the spirit of this thread. Like a vampire bat lurking in the shadows, waiting for an opportunity to sneak in and suck!

Not at all, i find the whole subject extremely interesting, but should you ever have an odd queen then i may be in the market, and i would never expect something for nothing.

In these circumstances the queen that is left is invariably damaged. She may have no antennae or some legs missing. (I was joking about the lurking thing, btw! )