The images are showing the interaction between the ants and the winged reproductive, which was moving up and down a log, then disappeared down a small crevice then re-appeared with ants around her.
Hi Roger, I'm pretty sure this is Papyrius nitidus, based on the deep concavity on the back margin of the head, which you can see pretty well on the top left ant in your first photo. The ant is very similar to Notoncus gilberti in general shape and colour but if you look at the other CNM Notoncus gilberti records you should see that the rear margin of the head is convex rather than distinctly concave. Cheers, Jon