Today (25/04/21) at around 2.30pm on a warm autumn afternoon I observed a male Satin Bowerbird at a partially constructed bower near the end of Downes Place, Hughes, on the edge of the Federal Golf Course. The bower was located underneath thick Cotoneaster understorey beneath a Tasmanian Blue Gum plantation. It was partially constructed in that about 15cm of the tunnel had been constructed both sides (the tunnel is usually about 50cm long) and was not fully woven and tightly meshed as finished tunnels are; there was also little evidence of gathered blue objects scattered about.
What was interesting was that as well as the bower-owner another fully blue male Bowerbird was present and seemed to be mimicking female behaviour. It approached the tunnel with a yellow leaf in its beak, which it deposited and then it hopped around making the sounds that female Bowerbirds make in the bower area. For its part the owner, whilst not hostile, was not highly engaged but kept an eye on the other male and hopped around slowly after it. It was also vocalising, but with nowhere near the intensity that males normally vocalise in the presence of a female.
I have heard that young, green males sometimes pretend to be females around a bower in order to hear and experience the male courtship behaviour and learn some tricks. Perhaps this was a male recently moulted into fully blue plumage not realising that he was no longer disguised. And perhaps the owner of the bower wasn’t advanced enough in its construction to be worried about the younger male damaging it, but was just keeping an eye on him.
I have some audio of the noise which I will analyse and compare to written descriptions of calls. If anyone has any thoughts or questions please let me know as I will probably write this up for Canberra Bird Notes.
—
