I have a theory...

[gemfyre]

I think the poor Rufous Whistler singing away outside is going to end up with an imposter in his nest.

*listens out for that cuckoo* They're about the same size, I doubt a Shining Bronze Cuckoo would parasitise something so small as a Brown Honeyeater, Weebill or Yellow-rumped Thornbill so the Whistler is it.