Pileated Females Battle for Territory (?)

They put on a big display just outside of my kitchen window.  I didn't have the best angle for shots and it was through the window... but this was an exciting moment to capture!

Here, one actually has the other's beak clamped in its own beak!  They really meant business; the 'winner' looked a bit bedraggled by the end.  I've never seen these birds behave like this before.  We've had multiple pileated woodpeckers on our property many times getting along just fine...