There's a youtube video here of a magpie's song if you've never heard it (well, I hope there's song. My computer was silent even with the speakers on and sound up, so please let me know if it's a dud!). Birds in Backyards also have the magpie's call on their website here.
The juvenile is the one perched on my hammock (front) and has the grey flecked chest. The adult is on the fountain (the fountain came with the house and is a fixture) and has a solid black chest.
The Australian magpies are not related to the European and North American magpies - we just seemed to borrow the name due to the black and white plumage.
Okay, so I thought I had a family visiting, but after consulting Pizzey (my bird book) it tells me that magpies hold territories by groups that can vary from a single pair to six adults or more and immatures. The sex-ratio can vary but in breeding territories, females tend to predominate and a dominant male can mate with multiple females.
The difference between males and females is that the female is a bit greyer than black, can be a bit mottled. So that's not something I'm ever going to be able to pick! Anyway, I have a bunch of magpies visiting me and they're such fun! I've been hand feeding them mince and have no fear of those massive beaks anymore! I've got a few horrid shots of blurred bird and my arm but my Dad's visiting so I might see if I can get some better photos of feeding.
I think magpies are one of my favourite birds.