Just now, the very local koel completed a hour-long calling
stint in its favourite pin oak. During this it was kept on the hop through
the foliage by a pair of currawongs, being finally evicted by one of
them. It seems to me that the exceptionally reclusive habits of koels
around Canberra (on which Shaun B for example has commented) might be due to
the number of currawongs and other harassers. It suits them to expose
themselves as little as possible while calling. Happens elsewhere of
course but I wonder whether this is not relative, directly related to the
harasser factor.