I am out here in Alapaha GA and there are these interesting bird houses that surprisingly house many Purple Martins. 15 could be counted in the flock at one time but I assume there were more in the bird houses. I could hear them communicate with each other and I saved a recording of it. What I noted first is the way they fly.  They take off in a burst flapping their wings many times. They keep flapping their wings their wings until they get to a height in which they begin to glide by extending their wings into almost a crescent moon shape. When they begin to land they once again flap their wings at a high rate until they reach their desired landing spot.

I could sometimes see them “fight” in a sense where they’d peck at another Purple Martin. I viewed this once while they were flying but also once when they were on the limbs of the bird houses. One of the Purple Martins flew and pecked at another and took its spot on the limb. They often took off at the same time. One would leave first and the others would follow soon after. Not all would leave, however, as a couple Martins would stay and others would come back before others. When in the bird houses, they would often stick their head out and not put their full body into the house.