It's an emu, I took the photo a few years back. South Australia is the driest state and Australia is the driest continent on earth. Yes it rains here but rain is infrequent and when it does rain it either rains briefly or it buckets down. Winters do tend to be a little wet some years but I rode my motorbike to work every day for a year and I only got wet 3 times. Marsupials are of course all mammals which kind of excludes birds from the genre.
Interesting. I did wonder whether it was an emu, but thought that I had read somewhere that they were extinct. Apparently in Tasmania they are. The marsupial reference was of course a joke .... one of the fascinating and unique aspects of Australia's native mammals though. Incidentally, I have a cousin who lives in Largs Bay; anywhere near you?