Steven Struyck’s video was documented out of the window of his study room in Penang, Malaysia. It shows two male Asian Koels (Eudynamys scolopacea) confronting each other. This went on for more than 30 minutes, each lunging at the other but never making bodily contacts. Occasionally one or the other lets out a series of loud cries. At 0:53 minutes, the koel on the left can be seen regurgitating a seed.
Such behavior is rather common, varying in levels of vocalisation and aggression HERE, HERE and HERE.
Can the males be establishing their pecking order?
Steven Struyck
Penang, Malaysia
14th February 2017