Mystery bird in Perth hills at night

Hiya,

We have had a bird living in our backyard for about 2 years now. It lives in a very dense tree so we can't get a picture of it to identify it.

However, it has a very loud, almost tropical sounding call that echoes in the bush around. And very oddly this nocturnal bird starts at about 11pm every night and goes almost all night/every night till the sun comes up. (I've gotten used to sleeping with ear plugs!)

Despite my initial irritation to it's inconvenient timing :P, I've grown quite fond of the bird, but am still perplexed by it! I've been speaking to people to try and find out what type of bird this is, but it doesn't seem to be a WA native. Is it lost?

I need your help please! :) I'd just like to ID it, to know if it needs help...or not!

See below for video footage I took tonight...

(if it doesn't work the link is - http://youtu.be/_nPhrtFQgig )

Thanks!