Domestic Muscovy Duck Quack Box/Bulla Bone/Syrnix

Couldn't find any good reference images for duck "quack boxes" online, so I decided it was well overdo I post better images of mine. I have some floating around iNat comments, but I think a journal post will be much easier to access and reference.
I don't know how I only now just found it, but a quick Google search showed Jake's Bones also has some bulla bone images, in the blog post "Strange bones #7 - the strangest bone yet ?", so I'll share that here too.
*3/17/20 update, found another voice box reference at Zygoma here, species uncertain. I also have a second Muscovy duck voice box on the way, in better condition than the one in this post.

"Quack boxes", or the bulla/bulla bone, are the syrinx of waterfowl. Syrinx as a whole are interesting phenomenon, an anatomical feature exclusive to birds. If you're interested in reading a study about the avian syrnix being an evolutionary novelty, you can find that in full and for free here. It's really not a bad read, I'd recommended at least reading the abstract and figure descriptions and skimming though the rest. If there are anatomical terms in this post that seem confusing, they're probably defined somewhere in that study.

The syrnix is inherently unique to birds, but the waterfowl syrnix is unique among birds. Their voice box looks in ways quite literally like a box.
Mine is unfortunately broken in a few places, but is complete enough it should give a good idea of what the bulla looks like. I have an observation attached to this journal that is a length of domestic Muscovy duck windpipe which I think shows the cartilage rings very well, but it is from a different specimen than the one that gave me this bulla.

On the top of the duck bulla you can see how the cartilage rings feed into the vocal organ itself.

Sadly from the top view you can see a lot of the damage.

In the image below you can see the back is very broken.

So that's my domestic Muscovy duck bulla bone. If there are any views that you would find helpful, message me and I'll gladly take more pictures.

Posted by lizardking lizardking, February 29, 2020 19:43


Photos / Sounds


Domestic Muscovy Duck (Cairina moschata var. domestica)




July 23, 2017 09:58 PM EDT


Windpipe from a roadkill muscovy duck. Didn't take any pictures of the rest of the bird so I don't necessarily expect anyone to agree with the ID being there's almost no way to independently verify this as Cairina moschata domestica but I thought it'd be cool to share.


Posted by lizardking over 1 year ago (Flag)

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