Handsome little guy. Do a search and you might see some good examples and maybe even a video.

Well, I've never seen any positive results on a surface so broken up, but that doesn't mean it's not possible. I'd be interested in seeing how it goes. Some of the colour shift paints could work but I wonder what the limit of the effect would be.

As for the birds: you have iridescence on crows and ravens (Corvids are cool) but even we have ruby-throated hummingbirds here. They're at our feeders through most of the summer... I happen to live a 'little' far north Bah, frigging starlings!

With iridescent paints, I have a heap of GW Nids and the trick is not to actually make them iridescent, but make them appear that way. Like painting black, looks wrong, use grey and darken it it looks right. I generally use an painting ink (by applying thin coats of a similar colour over a base colour) to make them appear that way. Not a perfect solution but hey it works and doesn't require a heap of skill to get the desired effect.

Go and get a heap of old mini's you don't care about and use them to experiment upon, I did and was surprised with what I learnt.

The metallic medium is great but doesn't produce in my experience a iridescent effect...