Koel face-off

 I have seen the male 'perch-off' and I thought only the males do so, and naturally over a female.

But females?  

I could hear a male Asian Koel (Eudynamys scolopaceus) calling incessantly in the distance and then shriekings, incessantly too close by.  Thinking that the two were merely communicating, I was not too quick to hurry over to check it out until the cries persisted louder and sharper.  There were two females in a duel!

They were pretty high up which accounted for why they were not the least concerned when I moved about trying to get the best angles against a mess of branches and twigs and hostile lighting.

And obviously only one could win, and unfortunately eventually I lost the loser to the even denser upper canopy, and the park regained a little peace when this one also retreated upward.