Ahhh, yes, the growl!

A male ekkie named Romeo was the very first parrot I have ever heard growling. He was a holy terror, Romeo was! I had to walk around the birdroom with a towel hanging on my front and another on my back because, if I didn't, he would run after me (wings half open and growling for all he was worth) to chase me out of the room -and, of course, bite me if he could reach me! He also did the swaying but he had to be furious to do it... On the other hand, Elsa, the female I had, would look all peaceful and nice and give not a single sign of anything and suddenly BAM! bite the heck out of you! She got me once in the web between my index and middle finger and bit so deep that she severed nerves to the point that I spent about two years getting the feeling back on half of my middle finger and, even to this day, there is a 'blind' spot still there...