Thursday, 23 July 2009

Dedicated to glam

These may not have been the photos he would have chosen for his portfolio, but this male Victoria's riflebird has no one but himself to blame for this selection. When I threw out a rotten banana, he was on it in a flash. His eagerness for overripe fruit gave me an opportunity to take these detailed, if undignified, portraits.

They don't do him justice. His plumage is half velvet, half satin. Basic black with a shimmering blue cap and gorget. There's a flash of iridescence over his tail: sometimes purple, sometimes blue. And pink and green on his flanks. He is a bird of the 70s. He would have looked right at home on Countdown.


Dave Coulter said...

Very handsome...

Snail said...

Isn't he just? I hadn't seen a male riflebird up that close before --- he was about 2m away --- so I'd never noticed the different textures of the feathers. I wonder how much difference there is in UV reflectance between the velvety feathers and the satiny ones. What does he look like to other birds?

Lulu Stader said...

Exciting idea, yes!

NB: great to have the size comparison with the gammy banana. I have never seen one of these and thought they must have been similar to sun birds in size at last, until I saw your banana pic.

Snail said...

They're about 25cm long. (That banana, by the way, is locally grown --- by a neighbour about 500m up the road. Having seen how the birds pounced on it, I don't think I'll be growing bananas here.)

Denis Wilson said...

Hi Bronwen,
Now here is a question for you.
Will the Rifle bird become more addicted to Bananas than you being addicted to photographing him?
Stunning bird.
Amazing colours.
There is much written on the science of colour reflection of glossy feathers. The colour is not based upon pigment. I am sure your bird is using the same optical tricks as the Peacock.
Check out Wikipedia on the Peacock (Peafowl).
"Such interference-based structural colour is especially important in producing the peacock's iridescent hues (which shimmer and change with viewing angle), since interference effects depend upon the angle of light, unlike chemical pigments."
Now you have "trained" your Riflebird, I look forward to many more photos.
Please, please, please.

mick said...

All those colors in 'basic black'. Very glamorous!

Gouldiae said...

Oooo Bronwen,
Beautiful detail. I'm going to follow up a bit on the comment by Denis. It's always fascinated me how the lines between feathers of different colours can be so sharp and uniform in some species, eg my favourite, the Gouldian Finch.
You're posting some wonderful stuff from up there.

Snail said...

Denis, I think these fellows are already addicted to bananas! They undertake regular raids on fruit bowls, even those inside houses. You have to shut unscreened windows if you're going outside!

You're right about the colour. The iridescence in these is definitely structural --- produced by interference patterns. I wrote something aeons ago on structural colours in birds. Fascinating stuff! Especially that structures involved in producing some of these colours are tiny and their arrangement incredibly precise.

Gouldiae, the crispness of those patterns is amazing. In Endless Forms Most Beautiful, Sean B. Carroll describes the underlying genetic mechanisms that create complex colour patterns. He discusses butterflies, but the principle is the same for birds. (I suppose!) It seems to come down to a series of switches that turn things on and off, coupled with gradients that interact with each other. It's just one big genetic Paint program.

Mick, ain't he somethin'? Of course, he's not perfect. You should hear him call --- sounds like a sulphur-crested cockatoo!

Denis Wilson said...

Hi Bronwen.
Well, trust me to assume that interference-based structural colours in bird feathers might be outside your field. Didn't mean to try to teach you to suck eggs.
Your other write up is very good indeed. I think I understand it all a little more having read your other post on the topic.
I hope the Rifle Bird falls in love with you (or your Bananas) and tries to impress you with a courtship display. That would be great.