Good question. HANZAB describes this bare skin for the Royal Spoonbill (volume 1B page 1095), so it would appear to be normal for the species. As to why, there
probably isn’t an answer: “Because its parents do”. As in a random evolutionary event. However this photo highlights something interesting. In this pose it is clear that the bird has brought the feathers well forward. It would be unlikely to do that in level
flight, as it would be destabilising. And the bird would have trouble closing the wing when perched if that was the normal pose. That indicates that most of the time, when held relaxed, the bare skin is normally covered by feathers laying flat. So it clearly
isn’t done at other times and so it could be a specific signalling of something. I don’t know what, Just like a cockatoo can raise a crest.
Similar although pink skin is certainly conspicuously normal for White Ibis.
Philip
From: Canberrabirds [
On Behalf Of Rob Geraghty via Canberrabirds
Sent: Thursday, 5 December, 2024 8:34 AM
To: Brian Jones
Cc: CanberraBirds Email List
Subject: Re: [Canberrabirds] Royal Spoonbill
I think it's normal? Photos I've taken of Ibis in flight show the same thing.
On Wed, 4 Dec 2024, 23:27 Brian Jones via Canberrabirds, <> wrote:
Does anyone know why this Royal Spoonbill has bare skin on the wings?
It was at Werribee in June.
Brian
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