Knowing nothing of birds, I send this to a group where they provide identification. Now it is in the flickr Field Guide to birds because they invited me. I am chuffed. But the bird is still weird. Apparently they drive away the other birds and because the other birds are not eating the bugs, the trees start to die (well this is according to the Australia Geographic).
One day, when I had to work on a Sunday evening, I spent the afternoon in centennial Park taking photos and this is one of the photos I took. The birds were quite tame, and if you were careful you could get quite close. There was this technique I remembered form a documentary where they said the trick was not to approach the animal directly. I do not have a powerful telephoto lens on my camera.