Blue tit argument...

The bird box has been recently used as an overnight roost for a blue tit.  On a couple of occasions we've had two in there.  Today was a little different since tit 1 didn't appreciate tit 2 in the same space, as can be seen in the following clip:

It's interesting that in addition to feet and beaks being used as offensive weapons, there are a couple of hooks using a wing...

Right hook

The posturing at the beginning is also interesting:

Posturing

Reminded me a bit of this