About 4 weeks back, I noticed a pair of gang-gangs showing a lot of interest in hollow branch in this tree. Galahs were also showing alot of interest and occasionally some eastern rosellas. All species were seen going into hollow during the day for about a week. It would appear that the galahs won - one has been seen sitting on the top of the hollow for last two weeks, but no sign of the gang-gangs. The park could be a suitable site for installation of a nesting hollow suitable for gang-gangs - they are regular visitors to the park and neighbouring houses during the year.
Thank Chris we actually have a sighting of Gang-gangs at this hollow. Can you remember whether you saw tham on teh same or a different day? Callocephalon fimbriatum (Gang-gang Cockatoo)