Chromerust and I showed up in the desert Sunday 8-3-2014 just after a rain storm went through dropping a decent amount of rain. At first we noticed none of the Acromyrmex nests were open, and they were nowhere to be seen, but later that night they all started opening their nests and rebuilding their mounds. We could see plenty alates popping their heads out, so we knew they should be flying soon.
We woke up the next morning around 8 am, and already we could see Acromyrmex males were flying everywhere, with the occasional female in the swarm. I quickly gathered up my things and headed over to the trees where I know they all like to dig their nests. At this point there were already plenty dealates digging founding chambers, so I looked around for the ones that still seemed to be wandering around. I collected quite a few of them and put them directly into test tubes for fear of them spitting out the fungus pellets inside the containers I keep them in temporarily. I noticed there was this one pile of dead bushes and debris that the males were all swarming around and the females would show up there and mate with a few of them on the ground and then fly off once finished. I can see they seem to only like digging their nests in partially shaded areas like under trees or large bushes.
Acromyrmex versicolor males swarming.
Acromyrmex versicolor alates mating.
Acromyrmex versicolor queen digging her founding chamber.
These queens chose to start digging their founding chambers right into the side of a loose dirt clod laying on the ground.
I ended up staying one more night, and the next morning there was another really small mating flight that took place again.
This is what the Ironwood trees look like that most all of the Acromyrmex in this part of the desert seem to nest under.
Once I got home I checked all their tubes for their fungus pellets, but wasn't finding anything. Finally, about two days later, I found a few of them had spit out their pellets.
The third day I checked them all with my microscope, and could only
find what I knew for sure were fungus pellets in about a quarter of the
tubes. I also noticed a lot of what looked like it could have once been
the fungus pellet in some. Unfortunately, I could only find a few that
looked like they had a tiny bit of fungus starting to grow on them, and I
couldn't even find the one in the picture above anymore. Some of the
queens when disturbed, would pick up the pellets and it looked like they
were destroying the fungus that had started to grow on them, so it's
probably best not to disturb them at all during this process. A few
times I noticed the queen would put the fungus in the cotton and get it
stuck in some of the strands, and then while trying to pull it loose, it
looked like she was damaging it pretty bad. I have a feeling this might
be what happened to a lot of the other pellets, and probably explains
why I was seeing pieces of what looked to once be fungus pellets. Next
year I will definitely have specially designed alternative founding
setups ready for them ahead of time to avoid this problem. I'm probably
going to try to quickly put something together and move the queens and
their fungus into them. We'll just have to wait and see what happens
Full journal can be found here.