What's that blue thing in the pond?

Little routines before settling to work involve stepping out into the garden to feed the fish. But what's that blue thing that looks like a ball or a toy that's fallen in? Oh! it's the head of a rainbow lorrikeet that has somehow fallen into the water. I don't have a working camera, so here's a picture from the web.

I pick up the bird. It's still warm, but clearly dead. Its colours are extraordinary and detailed; its black and green tail feathers elegantly splayed. I turn it over. Its belly is delicately speckled: each feather seems to have several different colours of flame and autumn leaf and blue sky. How did this poor creature come to this untimely end?

Hmm. Last night when I was bringing in the washing, I saw four large black crows in the lemon-scented gum, which the lorrikeets also like. Is this a territorial war in my back garden?