There must have been one hundred black cockatoos flying over the Parkland towards the city, which reminded me of all the bats flying the other way, a kind of symmetry six months down the track. (Unless Grey-headed flying foxes mysterioulsy turn into Yellow Tailed Black Cockatoos somewhere along the Upper reaches of the Yarra.)
You hear them before you see them. Even an Australian can find that sound alien*, at least in the city. Alien and awesome...
* See Creature of the Shade on making the familiar alien again.
(One of many great posts by a literary geographer)