lizardking's Journal

All pictures are taken in the field, and all bones were replaced after. None were collected.

An overview of some skeletal elements
Mandible is about 10 cm long and I have more pictures of it in the associated observation.

I am insanely grateful for this find.
I have a pretty difficult time finding a consolidated and comprehensive resource for turkey vulture post cranial bones, so I'm relieved to have a lot of skeletal elements all in one place.
When I first stumbled across these bones I was sort of in disbelief. I didn't know what they were, but I knew it was going to be special. In my original observation I document more of my journey figuring out what it is, and I really was elated when I pieced it together. I always fear sounding a bit insensitive or macabre when I document my joy at finding a skeleton, but I feel less of a need to explain myself with a vulture. I do love these animals in life deeply, and I don't wish for them to die, but I can be appreciative of what I learn after their deaths. And vultures specialize in appreciating the dead.

Humerus
About 14.5 cm
I never realized just how much pneumatization turkey vulture skeletons have, and I assume other vultures as well. It makes sense though, with how high and long they fly, they need as much air as they can get, and birds can store air in their bones.

Ulna
For fun, the bird's ulna against my ulna/forearm.

More serious now. Ulna measures about 16.5 cm in length.



Visible and pronounced quill knobs.

Radius
About 15.5 cm

Carpometacarpus
About 8 cm
Very impressive pneumatization here as well.

Coracoid
About 7 cm
This was very enlightening, I find myself having coracoid problems identifying on here. They are such a unique bone but I just don't excel at differentiating them. This has such a huge "mouth", I think it might of solved at least one observation I've been sitting on. Now just to find it again...


Below shows that huge "mouth"

Wishbone
About 5.5 cm. Not sure why I didn't get good pictures of this when I revisited, or maybe I just lost them. Again, displays impressive pneumatization.

Keel, none of the rest of the sternum

Rib
About 5.5 cm

Vertebra
I like how thin and sharp the processes are. In general, very slender and sleek in shape.

Pelvis
About 10 cm
These are pictures from the original observation because when I went back to take these pictures, I could not for the life of me find the pelvis. I do have turkey vulture pelvis references (see below), so this wasn't a huge loss, other than the fact the pelvis is my favorite skeletal element in birds and I was already facing a comedy of errors. I will just have to include these slightly worse looking pictures in interest of having a more comprehensive turkey vulture bone reference.

Femur
Femur, about 9 cm. Couldn't find this one again when I revisited.

Tibiotarsus
About 15 cm.

Tarsometatarsus
About 8.5 cm

I put all of the bones back into the fenced off area.

Extra turkey vulture skeleton resources:
BoneId has the tarsometatarsus, humerus, carpometacarpus, skull, tibiotarsus, femur, sternum, and coracoid.
http://www.boneid.net/search/?product_cat=turkey-vulture&order=DESC

The Smithsonian has the skull and sternum
https://collections.nmnh.si.edu/search/birds/?ark=ark:/65665/31494451fead240a9a8d04d0389aefbdd

Osteology of birds, Robert Wilson Shufeldt, has much of the post cranial torso, articulated and lacking limb bones. Great pelvis reference though.
https://imgur.com/sd1wwCs
https://imgur.com/kfOhIKb

A random twitter post of some turkey vulture bones- vertebra, wishbone, femur, pelvis, two tarsometatarsus, a carpometacarpus and tibiotarsus.
https://i.imgur.com/4IileCC.png

Skullsite of course has the skull
https://skullsite.com/skullpage/cathartes-aura-turkey-vulture/

And Digimorph as a turkey vulture skull erroneously labeled black vulture. I asked them to fix it, they didn't, oh well.
https://digimorph.org/specimens/Coragyps_atratus/

I had a strange privilege of being able to find and examine a Great Horned Owl skeleton in person. There is no replacement for learning about morphological features in the physical, so any time I get to learn from these bird skeletons in the wild I try to really savor and digest the moment. I am deeply appreciative of the birds, and understand there was a loss of life to give me this learning opportunity. And that felt quiet heavy here. The strange part of this privilege is the acquaintanceship. I knew this owl, presumably, for years. Or perhaps its mate, or some other relative, but in some way I'm quite sure I knew this animal, either directly or through a mutual owl. I have links to observations of my previous interactions with this bird at the end of the post.
...
My last post with the heron bones was a lot of kvetching, but this tone is different. I've been lucky with bone finding in the field these past few months, and that has helped me make easier connections in regards to my identifications on here. This owl itself was a pretty reinvigorating experience. I try to have a lot of iNat time daily at this point. There is a good likelihood I have missed notifications from my several months off though, and you can see free to @ me or message me if you feel something needs a look. My skills are still shaky but I've been making some notable improvements lately.
...
Now for the morphology. I learned more about intricate details and characteristics of owl skeletons than I thought possible. Since I cannot legally keep any of these bones, hopefully these pictures can help me remember these details that only became clear to me in person. However, I have pretty bad spacial interpretation skills from pictures, so already my memory is iffy on some of these. But certain things I learned in person were strong enough to stick with me, even as I leave the bones behind.

All of the bones found. Notably missing cranium and pelvis.

Sternum.
First skeletal element noticed from the owl. I pointed out some mushrooms to Geronimo and he found the sternum a few inches away.

As I've previously mentioned in my journal, it's rare I have exposure to a diversity of bird bones in person, and as such my field identification mental process is sloppier than on here. Pictures are very different than physical.

I didn't guess owl initially. But the double posterior lateral processes immediately signified whatever this was, it is MBTA protected. Possibilities included shorebird or ibis, though I doubted both options. I had a moment or so of strongly leaning on vulture.

Mandible.
After a bit of frantic scouring through Australian pine needles, I found the mandible and all became clear. Its wide, triangular shape is very recognizable, suiting the wide, bulbous frame of owl skulls.

Photo here is for emphasis of the foramen.

Coracoid.
The coracoid was fantastic to play with in person. I've seen owl coracoid pictures and illustrations, but handling it was like seeing it for the first time.

I find the foramen below the head fascinating. Most of these pictures are trying to capture that.


The shape of the whole distal end was very hard to capture in photos. Interesting shape, but memory fades of what the specific elements I wanted to capture here were.

Vertebra.
The vertebra were beyond breath taking.

This thoracic vertebra was my favorite.

There is this delightful process at the bottom of the vertebra, I keep on referring to it in my head as a "crown", in a sort of three pronged Basquiat crown sense, not as in an anatomical crown.

I sadly did a garbage job of capturing it in photographs.

But it is truly a magnificent little feature, as far as I know distinct to owls, though I can't say that with total confidence.

Quadrate.
Wow, these were bad quality photos. My bad.
The quadrate is a tiny bone attached to bird skulls. It is part of jaw articulation.

I don't know much about quadrate morphology, one day this might be more helpful to me though. No new synapses really connected with this one though. But it will be a bone I pay more mind too. I thought this was a cuneiform or scapholunar or something at first, also my bad.

Ulna.
Very pronounced quill knobs.

Ulnas and radiuses.

Digit and claw.

I'm not actually sure I articulated this correctly.

Tarsometatarsus.
Another delight, especially because I have had tarsometatarsus problems as of late. It's wonderfully and distinctly stout and thick.

Leg- Femur, tibiotarsuses, and tarsometatarsus.

Phalanx.
Very enlightening. I have thus far only been able to reliably identify Shorebird phalanx. This was such a unique shape, I think I might be able to recognize owl from now on too. I've seen the Snowy Owl illustration in Lee Post's bird building book, but I have never realized how unique owl phalanx were until this.

Almost shaped like a mammal scapula.

Scapula.
I'm still scapula challenged. Not much to say here.

Carpometacarpus.
Another treasured and enlightening find. The shape of the distal end is distinct and delightful. The lines of it are so interesting, I'm not sure how to put words on it. Almost heart shaped from the palmar view (I think? Whatever this one is.)
From Olsen's Osetology for the Archeologist:
"Facet digit III extended well beyond that of facet digit II."

(And I think this is the extensor view?)

I am deeply thankful for this experience, and all of the osteological knowledge this owl has incidentally given me through the years. It truly was reinvigorating, and hopefully my IDs on here will come easier and more accurately. Every time I am able to train my eye on a new identifying morphological feature on one species' bones, I can start to see it in others as well. I have been working on staying more active for over a month or so now, and moving forward also plan to make more posts, either on here or my associated off site blog. I still have a backlog of observations I am reviewing from both my hiatus and from a lack of resources/knowledge, but I'm working on whittling away on them. I should be able to handle @'s more reliably again, so feel free to @ or message me if help is needed, I will try and do my best. I do sometimes miss them, but I will always try my best to contribute.
...

The journal feature is a nightmare to add observations too, so the only associated one will be of the skeleton. But here are links of the other Wolf Lake owl interactions over the past three years:
https://www.inaturalist.org/observations/179758942
https://www.inaturalist.org/observations/118975267
https://www.inaturalist.org/observations/118972645
https://www.inaturalist.org/observations/118972685
https://www.inaturalist.org/observations/67317590
https://www.inaturalist.org/observations/37721974
https://www.inaturalist.org/observations/37721696
https://www.inaturalist.org/observations/37721810
https://www.inaturalist.org/observations/37721920

So happens one of my favorite albums is a whole woodland fable that has a dirge for its owl protagonist. I think she is a Bubo bubo. And she befriends a wolf, so I think it fits as the send off to this post, and for the Wolf Lake Bubo virginianus itself.
Given to the wind. Sky burial

This is an abridged explanation of my growing inactivity, accompanied by some heron bones I found. It makes sense together, kind of.
The longer version is here:
https://avianosteology.blogspot.com/2023/02/some-heron-bones-and-inactivity-extended.html

This is going to be a bit convoluted and could be two separate posts but I feel it appropriate to keep as one.

I have been increasingly slow with IDs, and I will probably be far more inactive in the coming weeks. I am going to try and catch up on everything one day, but it will take a lot of time. I decided I wanted to put some explanation out there for why. There are my two main reasons for increasing inactivity:

1. Have growing need to use time and brain power for more immediately useful life skills
2. Becoming more aware of and frustrated by my own limits regarding bird bone IDing

Point one isn't relevant to iNat but I think needed mentioning, and point 2 ties into the heron pelvises and mandible.

I have encountered this before with an ibis skeleton I found. More recently, with a woodpecker wing. My initial reaction in the field upon finding bird bones is and I think always will be excitement and wonder. But after that, unless it is part of the intersection of the few families and skeletal elements I know like the back of my hand, it's utter confusion.

...
IDing on iNat for me is often considerably time consuming. It can take me half an hour of reviewing references for comparison, not including the time spent explaining my ID if I find one and making graphics. Sometimes an ID can take weeks of background research.

I have over 2,000 bird bone IDs with many hours tied into them. And so when I am in the field, utterly lost to even guess an order of the bird bone I found, there is a frustration. Worse when I return and can't puzzle out through my comparative resources. I understand more specific identification will more or less always depend on comparison, but when I can't even guess order in the field, it gets discouraging.

...
I'm kind of a limited learner. I use illustrations, but they often leave me confused, missing something. I prefer photographs, they feel very effective on the world of iNat or any other little internet corner I might be around on to help with bird bones. But when faced with a physical bone, I realize how limited photographs are too. Especially because I have terrible spacial awareness. Precise measurements are sometimes wholly necessary for species differentiation. But a lot of times I need them when IDing for others on iNat just because I am a terrible judge of size without numbers. I can often be found holding my hand and some bones to my computer screen, trying to parse out what I'm seeing.
...

All of this is to say, I am no natural at this. My knowledge is hard gained and incomplete. I often feel like I am trying to grasp a new language that is always slightly out of reach. Bird bone resources are hard to come by. Natural history museums have a track record of only keeping bird skins, not the bones. The MBTA means North American birds are harder to get references for, and I can't learn off of most physical bones outside of the field, which is unfortunately the best way I learn. There is not much interest in birder and ornithology circles for avian osteology, and so knowledge within community about bones is comparatively less than among mammal or herp circles.

...
At this point, I tend to not respond to a lot of my @'s. And I feel bad about that. But I keep them all in links I email to myself. I am deeply grateful for the group of people who @ me a lot, even though I feel less than faithful and diligent. But you are seen, and I am doing background research, and I am thankful for you guys to keep me motivated to push myself to learn and grow more and keep time carved out for iNat even when I work on other stuff. I am quiet and naturally have a withdrawn presence on and off the internet, but I really appreciate all of you. I am too shy to @ anyone specifically, but if you think you might be included in this, you are.
...

One day I'm going to try and get through all of them, but that will take a lot of outward inactivity as I get spend a lot of time doing my own behind the scenes research.

...

So, how is this massive rant relevant to the heron bones? They were another significant straw of frustration. I want to share my extra pictures of them, but have almost nothing constructive to say about them. Because I just don't know. I have a pdf about differentiating heron pelvises I will review, likely during my planned dormancy. Then I might be able to add something better about them.

Mostly for personal reference and as an explanation for my IDs, some of my description words might seem like nonsense but I will gladly explain if asked. Many of my personal descriptions are also intended as an accompaniment with, not replacement for, photographs or a specimen. Many of these descriptions are based off of single specimen, which limits scope.
Feel free to comment any questions, suggestions, corrections, thoughts, etc
This is a work in progress.

ALL DESCRIPTIONS ARE SECOND TO COMPARISON WITH SPECIMEN

Below are the resources used:
https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1000&context=icwdmother [1]

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1014&context=nebgamepubs

https://virtual.imnh.iri.isu.edu/Osteo/Birds/12 [2]

Osteology for the Archaeologist, Stanley John Olsen. [3]

https://www.flickr.com/photos/jrochester/albums/72157651043869057

https://collections.nmnh.si.edu/search/birds/?ark=ark:/65665/36845b8eb2e224bc3a357dd25f86f8718

Osteology of birds, Robert Wilson Shufeldt. [4]

Anatidae Sternum Questions

Significant ventral manubrial spine? Y/N
Posterior Lateral process exceed xiphial area? Y/N
Posterior Lateral process attach to xiphial area?Y/N
Xiphial area shape?
Sterno-coracoidal process shape?
Special notes?

Clangula hyemalis:
Significant ventral manubrial spine? Yes, "Single broad ventral manubrial spine". [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Extremely unique, protruding and rounded, like if it had the lipped xiphial area of a goose but grew a lump on the edge.
Sterno-coracoidal process shape? Square, surface grooved
Special notes? Loon like.
[2]

Oxyura jamaicensis
Significant ventral manubrial spine? "Single broad ventral manubrial spine" [1]
which is uniquely forked at the end"
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Sterno-coracoidal process shape? Square, surface grooved
Xiphial area shape? Straight, wide, short
Special notes? Postieor lateral proces espically thick and stubby
https://www.flickr.com/photos/jrochester/16060949260/in/gallery-66337245@N00-72157678747666368/

Melanitta americana
Significant ventral manubrial spine? "Zero to 2 ventral manubrial spines"[1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area?No
Xiphial area shape? Straight
Sterno-coracoidal process shape? Rectangular
Special notes?

Melanitta deglandi
Significant ventral manubrial spine? not sigifcant, "Zero to 2 ventral manubrial spines" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Straight
Sterno-coracoidal process shape? Short, rectangular
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/White_Winged_Scoter/653[2]

Melanitta nigra
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? No, xiphial area slightly exceed processes
Posterior Lateral process attach to xiphial area?No
Sterno-coracoidal process shape? Very short triangular.
Xiphial area shape? Very uniquely shaped. Almost like short long tailed duck.
Special notes?
[2]
https://virtual.imnh.iri.isu.edu/Osteo/View/Common_Scoter/647
Also: https://www.flickr.com/photos/jrochester/16232300905/in/gallery-66337245@N00-72157678747666368/

Melanitta perspicillata
Significant ventral manubrial spine?"Zero to 2 ventral manubrial spine" [1]
Posterior Lateral process exceed xiphial area? Not significantly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Straight
Sterno-coracoidal process shape? Rectangular
Special notes?

Somateria mollissima
Significant ventral manubrial spine? Skinny, "Zero to 2 ventral manubrial spines" [1]
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Sterno-coracoidal process shape? Down turned triangles.
Xiphial area shape?
Special notes? posterior processes thick

https://virtual.imnh.iri.isu.edu/Osteo/View/American_Eider/652[2]
Also: https://www.flickr.com/photos/jrochester/16232300905/in/gallery-66337245@N00-72157678747666368/

Somateria spectabilis
Significant ventral manubrial spine? No, "Zero to 2 ventral manubrial spines" [1]
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Mostly straight
Sterno-coracoidal process shape? Down turned triangles
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/King_Eider/656

Histrionicus histrionicus
Significant ventral manubrial spine? "Two ventral manubrial spi nes" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? V shaped
Sterno-coracoidal process shape? Triagular
Special notes?

Aythya marila
Significant ventral manubrial spine? Very slight. "Two ventral manubrial spines"[1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Slight, seems possible
Xiphial area shape? Straight
Sterno-coracoidal process shape? Down turned, very pointed
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/Greater_Scaup/581[2]

Aythya collaris
Significant ventral manubrial spine? "Two ventral manubrial spines." [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? "Square xipial area. Sternal notches restricted posteriorly, at times with posterior lateral processes joined to corners of xiphial area" [3]
Xiphial area shape? Straight
Sterno-coracoidal process shape? Pointed
Special notes? Signifcant margin between crest and Sterno-coracoidal process

Aythya fuligula
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Wide, mostly flat, slight V
Sterno-coracoidal process shape? Pointed
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/Lesser_Scaup/589

(similar apply to lesser scaup, redhead [1])

Merganser

Mergus serrator
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? No, xiphial area excess processes
Posterior Lateral process attach to xiphial area? Yes
Sterno-coracoidal process shape? Square/pointed
Xiphial area shape? Unique straight with a bump
Special notes? Keel very long. Unique shape,
https://www.flickr.com/photos/jrochester/16230417211/in/gallery-66337245@N00-72157678747666368/
[4]

Mergus merganser
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No, but maybe
Xiphial area shape? Curved
Sterno-coracoidal process shape? Square
Special notes? Keel very long.
https://www.flickr.com/photos/jrochester/16232300905/in/gallery-66337245@N00-72157678747666368/

Lophodytes cucullatus
Significant ventral manubrial spine? "Normally no ventral or dorsal manubrial
spines. " [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Yes
Xiphial area shape?
Sterno-coracoidal process shape? Pointed
Special notes?

Bucephala

Bucephala clangula
Significant ventral manubrial spine? "No ventral manubrial spine" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Yes
Xiphial area shape? Slight curve mostly straight
Sterno-coracoidal process shape? Pointed
Special notes?

Bucephala islandica
Significant ventral manubrial spine? "No ventral manubrial spine" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Yes
Xiphial area shape? Slight curve mostly straight
Sterno-coracoidal process shape? Clubbed rectangular
Special notes?
[4]

Bucephala albeola
Significant ventral manubrial spine? "No ventral manubrial spine" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Yes
Xiphial area shape? Slight curve mostly straight
Sterno-coracoidal process shape? Pointed
Special notes?

Polysticta stelleri
Significant ventral manubrial spine? "One short prominent ventral manubrial
spines" [1]
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area?o
Xiphial area shape? Straight
Sterno-coracoidal process shape? Rectangular, then clubbed
Special notes?

Dendrocygna autumnalis and Dendrocygna bicolor
Significant ventral manubrial spine? "No ventral manubrial spine" [1]
Posterior Lateral process exceed xiphial area? Yes
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? V
Sterno-coracoidal process shape? Short
Special notes? "Large oblong pneumatic
fossa 2.5-5.0 mm wide" [1]

ANAS
Teals:
Anas cyanoptera, Anas crecca carolinensis
Significant ventral manubrial spine? " Long ventral manubrial spine several mm in length. " [1]
Posterior Lateral process exceed xiphial area? Not significantly
Posterior Lateral process attach to xiphial area? Not always
Xiphial area shape? Straight
Sterno-coracoidal process shape? Square
Special notes?
http://www.clemson.edu/science/departments/biosci/research/museum/exhibit8/index.html

Anas crecca
Significant ventral manubrial spine? Yes, " Long ventral manubrial spine several mm in length. " [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Yes
Xiphial area shape? Straight
Sterno-coracoidal process shape? Extremely short
Special notes?
[2]

Anas discors
Significant ventral manubrial spine? Yes, but spine has slight curve.
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Not always
Xiphial area shape? Straight
Sterno-coracoidal process shape? Extremely short
[2]

MORE ANAS
black duck. gadwall, mallard, mottled duck, pintail, shoveler, widgeon:
Significant ventral manubrial spine? "Single, long ventral manubrial spine several mrn in length" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? Not always but often
Xiphial area shape? Straight
Sterno-coracoidal process shape? Pointed
Special notes?
https://www.flickr.com/photos/jrochester/16247659482/in/gallery-66337245@N00-72157678747666368/
https://virtual.imnh.iri.isu.edu/Osteo/View/American_Widgeon/650
https://virtual.imnh.iri.isu.edu/Osteo/View/Black_Duck/648

Wood duck
Significant ventral manubrial spine? "Either has a single short ventral manubrial spine up to 2 mm or none at all" [1]
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Straight
Sterno-coracoidal process shape? Very slight clubbed
Special notes? Posterior Lateral process aren't clubbed at the end like most ducks. Very simplistic shape.
[2]

Muscovy Duck
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Deep V shape
Sterno-coracoidal process shape? Pointy and clubbed
Special notes?

Egyptian goose
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Very wide V
Sterno-coracoidal process shape? Unique, spikey
Special notes?
Pictures to come

Tadorna Tadorna
Significant ventral manubrial spine? Yes
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Straight
Sterno-coracoidal process shape? Elf ear like
Special notes?
https://www.flickr.com/photos/jrochester/16062173579/in/gallery-66337245@N00-72157678747666368/

Spatula clypeata
Significant ventral manubrial spine? Yes
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Slightly wide, curved
Sterno-coracoidal process shape? Clubbed
Special notes?
[4]

GEESE

Anseranas semipalmata
Significant ventral manubrial spine? No
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? Not really?
Xiphial area shape? Small and round
Sterno-coracoidal process shape? Short
Special notes? Very strange and unique.
https://collections.nmnh.si.edu/search/birds/?ark=ark:/65665/36040dfc439c74badbe54162ed4d74d09

Asner albifrons
Significant ventral manubrial spine? Yes, short and clubbed.
Posterior Lateral process exceed xiphial area? Yes
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Small, straight
Sterno-coracoidal process shape? Short
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/Pacific_White_Fronted_Goose/663

Anser brachyrhynchus
Significant ventral manubrial spine? Yes, short and clubbed.
Posterior Lateral process exceed xiphial area? Yes
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? V, wide
Sterno-coracoidal process shape? Short
Special notes?
https://www.flickr.com/photos/jrochester/16010853649/in/gallery-66337245@N00-72157678747666368/

Branta bernicla
Significant ventral manubrial spine?
Posterior Lateral process exceed xiphial area? Not significantly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Straight but lipped
Sterno-coracoidal process shape? Short but pointed
Special notes?
https://virtual.imnh.iri.isu.edu/Osteo/View/Brant_Goose/635

Branta canadensis
Significant ventral manubrial spine? Short, very strong, bow shaped
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Lipped
Sterno-coracoidal process shape? Short
Special notes?
[2]
https://virtual.imnh.iri.isu.edu/Osteo/View/Canada_Goose/578

https://virtual.imnh.iri.isu.edu/Osteo/View/Canada_Goose/636

Chen caerulescens
Significant ventral manubrial spine? Short and clubbed
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area?Yes
Xiphial area shape? Wide
Sterno-coracoidal process shape? Short
Special notes?

https://virtual.imnh.iri.isu.edu/Osteo/View/Snow_Goose/638

SWANS.
Deep keel that stores windpipe typical of Cygnus.

Cygnus cygnus
Significant ventral manubrial spine? Yes
Posterior Lateral process exceed xiphial area? No, xiphial area exceeds processes.
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Wider bow shape
Sterno-coracoidal process shape? Short
Special notes?
https://www.flickr.com/photos/jrochester/16007639270/in/gallery-66337245@N00-72157678747666368/

Cygnus olor
Significant ventral manubrial spine? Slight
Posterior Lateral process exceed xiphial area? Slightly
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Small bow
Sterno-coracoidal process shape? Short but wide
Special notes? Lacks keel for extra windpipe. Hence mute.
https://www.flickr.com/photos/jrochester/16007639270/in/gallery-66337245@N00-72157678747666368/

Cygnus columbianus
Significant ventral manubrial spine? Yes
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Short, square
Sterno-coracoidal process shape? Small
Special notes?
https://virtual.imnh.iri.isu.edu/Osteo/View/Tundra_Swan/573

Cygnus buccinator
Significant ventral manubrial spine? Yes
Posterior Lateral process exceed xiphial area? No
Posterior Lateral process attach to xiphial area? No
Xiphial area shape? Square
Sterno-coracoidal process shape? Short
Special notes?
https://virtual.imnh.iri.isu.edu/Osteo/View/Trumpeter_Swan/649

A few months ago, in an otherwise apparently standard Domestic Muscovy Duck (Cairina moschata var. domestica) skeleton, I came across an extremely deformed humerus.
On the left is the deformed humerus, on the right the bird's seemingly healthy humerus.

The humerus' deformity I believe to be the result of a healed bone fracture.

Below are long bones from various carnivorans, displaying different healed fractures. Not all the deformities are especially obvious, but D, a healed bobcat (Lynx rufus) femur, stood out as a similar level of deformed to my Muscovy humerus.


From Argyros, George & Roth, Aaron. (2016). Prevalence of healed long-bone fractures in wild carnivores from the northeastern United States. Journal of Zoo and Wildlife Medicine. 47. 879-882. 10.1638/2015-0180.1.

Although I am fairly confident the humerus is a healed fracture, and that is why it is deformed, I still have a lot of questions I, ideally, would of found answers to, and explored them more in this journal post. It's unclear what eventually killed the duck, but with how healed the humerus was, I assume it lived substantially long after the initial injury. I don't know what caused the injury, how long it could take for a fracture like this to heal, or what the duck's life was like after the injury.

The only other conclusion I have made from this aside from the fact the humerus is a healed fracture as opposed to say, a genetic deformity, is that this duck's prolonged survival to heal after a significant injury implies there are no alligators at the lake it lived. The article Noteworthy healed fractures in Some north american artiodactyla (Smith Grandstaff, B., Deeble, E., Parris, D.) studies artiodactyl skeletons with long bone injuries, and explains "these specimens demonstrate the resiliency of injured artiodactyls in wild populations with few large predators". I know I can't assume studies on deer and pronghorn can translate flawlessly to avians, but I have a hard time imaging an almost literal sitting duck could live long enough to permit healing if living among predators. No gators are observed there on iNaturalist, and I haven't heard reports of gators, though I know they aren't totally uncommon for the surrounding area. But, this duck does give me confidence there are no gators, at least at the time of the duck's life, at the lake. Guess that means I don't have to worry terribly much about the times I almost fall into lake looking for bones along the steep and rocky shoreline.

Though, back to the duck being an almost literal sitting duck, it is actually difficult to know how impaired it was by the wing bone injury.
The article Waders (Scolopacidae) surviving despite malaligned leg fractures in the wild: kinematics of bipedal locomotion (Reichert, J., Mayr, G., Wilke, T. et al.) explores the implications of healed long bone injuries in the wild on the function of the injured animals, describing information on the subject as "scarce". They studied wader leg injuries, and although the birds presumably had to make some life style changes to survive, their movement wasn't terribly impaired.

Well, that is about it for my findings. I was hoping to have have more for this, and not just post bizarre bone pictures without more context, and although I was able to find more context it wasn't all I hoped. At the very least I suppose it was validating to see Reichert, J., Mayr, G., Wilke, T. et al. describe information on the subject as scarce. I could find more on fractures healed with veterinary methods, but that is different than fractures healed in wild settings. I assume my duck here couldn't fly, but even that I can't be totally certain of. Also interesting to learn more places in osteology there are dearths of information.

Argyros, George & Roth, Aaron. (2016). Prevalence of healed long-bone fractures in wild carnivores from the northeastern United States. Journal of Zoo and Wildlife Medicine. 47. 879-882. 10.1638/2015-0180.1. https://www.researchgate.net/figure/Healed-long-bone-fractures-observed-in-museum-specimens-of-wild-carnivores-Scale-bar-14_fig1_309259224

Reichert, J., Mayr, G., Wilke, T. et al. Waders (Scolopacidae) surviving despite malaligned leg fractures in the wild: kinematics of bipedal locomotion. Avian Res 8, 23 (2017). https://doi.org/10.1186/s40657-017-0082-5
https://rdcu.be/ctreW

NOTEWORTHY HEALED FRACTURES IN
SOME NORTH AMERICAN ARTIODACTYLA
Barbara Smith Grandstaff, Eric Deeble, and David C. Parris
School of Veterinary Medicine
University of Pennsylvania
Philadelphia, PA 19104
2
Bureau of Natural History
New Jersey State Museum
Trenton, NJ 08625
https://sdaos.org/wp-content/uploads/pdfs/2015/127-139.pdf

When IDing bones, one of the most common mistakes I come across is confusion between bird and mammal skulls and pelvises. Not just confusing a bird pelvis for a mammal one, but often a bird pelvis for a mammal skull. Since this is so common, I decided to have a post with a more in depth explanation.

I will be using a Domestic Muscovy Duck (Cairina moschata var. domestica) and Gray Fox (Urocyon cinereoargenteus) to demonstrate.

From left to right: Duck pelvis, duck skull, fox skull, fox pelvis.
......................................................................................................
First I will start with the most common mistake of this order confusion, mistaking a bird pelvis as a mammal skull. Most of the confusion seems to come from the bird pelvis' acetabulum, circled below.
(see also, Parts of a bird pelvis: https://www.inaturalist.org/journal/lizardking/30724-parts-of-a-bird-pelvis)

(Left, duck pelvis, right, fox skull.)
This is where the femur articulates into the pelvis. However, its perfectly circle shape is often mistaken as an eye socket. As you can see on the fox skull, eye sockets aren't actually that clean and circle. It is a very common mistake though, and I will also detail some ways to tell the bone is a pelvis, and not a skull.

(Left, duck pelvis, right, fox skull.)
Both the duck pelvis and fox skull have a similar form, a wider posterior (back) and then a more narrow anterior (front), the fox's snout seeming analogous to the duck's anterior. That, however, when turned upside-down, is revealed to be not dental and nasal structures, but fused vertebra.

(Left, duck pelvis, right, fox skull.)
Bird bones have to be very efficient. Strong, supportive, but light weight. They have a lot of fusion, and the pelvic girdle is a great example of this. Much of the lower spine is fused to be part of the pelvis. So while the anterior of a mammal skull should have teeth or holes for teeth, the anterior of a bird pelvis -and its entire length- has fused vertebra.
......................................................................................................
Second is a less obvious, but still common, confusion.
When bird skulls have their beaks, they are typically easily distinguishable from mammal skulls. I have seen confusion when the bill is broken off, and also on occasion rabbit skulls being confused for avian. The easiest way to tell an avian skull from a mammalian one is the rounded "bump", or occipital condyle, on the skull, around the foramen magnum, or the opening at the back of the skull the spinal cord runs through. Birds have one, right under the center of the foramen magnum, and mammals have two, on either side of the opening.

Left, duck skull, single arrow pointing to it's single occipital condyle. Right, fox skull, arrows pointing to both occipital condyles.

......................................................................................................
And last is a less common, but still frequent cause of confusion, mistaking bird and mammal pelvis.

(Left, duck pelvis, right, fox pelvis)
As said above, bird bones have incredible efficiency of strength and lightness, and fusion is one mechanism that helps achieve this. Mammals don't have this same need, and the structure of their pelvises appear far more simplistic. Bird pelvic girdles have a lot of spine fused to the pelvic bones, where mammals lack any apparent vertebra in their structure*.

(Left, duck pelvis, right, fox pelvis)
Also discussed earlier, the circle opening confused for an eye socket is actually the acetabulum, where the femur attaches to the pelvis. In mammals, this is less of an opening and more of a crater or indent. The spherical indent on the side of the pelvis is the fox's acetabulum.

*The exception to this is the sacrum, which all mammal pelvises have, but often falls off as an animal decays, and isn't always found with the pelvis when exploring in nature. My fox pelvis didn't have the sacrum still on it when found, but here is what one would look like: https://www.boneid.net/product/anterior-view-grey-fox-sacrum/
It sits in between in the pelvis.
It isn't as large or thing as typical of avian pelvic structures, and mammal sacrums in general tend to be bulkier than anything typical of avians.

......................................................................................................

This is an overview, a general explanation to help educate and also to explain my own personal ID corrections, but I can gladly explain aspects more in depth, and as always, I am always open to help with anything bird bone related. Lee Post has an excellent book that covers how to differentiate the entire avian skeleton from mammalian, The Bird Building Book.

https://www.inaturalist.org/journal/lizardking/37605-white-ibis-skeleton

Wish bone

sternum

sternum and vertebra

vertebra

wing girdle;
humerus, coracoid, scapula

coracoid, scapula

corcaoid

humeurs

both wings

femur

tibiotarsus

Skull images credit to skullsite.com and Royal CS Museums' Avian Osteology.
This is an incomplete and oversimplified guide, but helpful for me to review back to and potentially link to when IDing, or as a good introduction for people looking to start building knowledge on osteology of the skulls of birds of prey. Unfortunately I lack reference material for many of the unlisted Accipitriformes and they therefore had to be excluded, but this covers some of the most common. If anyone wants more specific advice, please comment or message me

Bald Eagle (Haliaeetus leucocephalus)

-Massive size (12 or more cm)
-Almost entirely, and in some specimen entirely, solid sheet of bone between eyes (circled)
-Extremely pronounced and thick beak

(https://skullsite.com/skullpage/haliaeetus-leucocephalus-bald-eagle/)

Golden Eagle (Aquila chrysaetos)

-About bald eagle sized (12 cm) but:
~Has perforation in sheet of bone between eyes
~Has smaller bill

(https://skullsite.com/skullpage/aquila-chrysaetos-golden-eagle/)

[for a more in depth comparison of golden vs bald eagle skeletons, see https://tinyurl.com/mzpcz1n8]

Snail Kite (Rostrhamus sociabilis)

-Completely unique bill shape, exceptionally delicate and curved

(https://skullsite.com/skullpage/rostrhamus-sociabilis-snail-kite/)

Osprey (Pandion haliaetus)

-Round and almost circular nasal (circled)
-Particularly curved bill

(https://skullsite.com/skullpage/pandion-haliaetus-osprey/)

Hen Harrier (Circus cyaneus)

-Comparatively slender frontal (circled)

(https://royalbcmuseum.bc.ca/Natural_History/Bones/Species-Pages/NOHA.htm for harrier, other two skulls from skullsite)

Harris's Hawk (Parabuteo unicinctus)

-Yellow on bill sheath

(https://skullsite.com/skullpage/parabuteo-unicinctus-harriss-hawk/)

Buteo
(pictured is a red tailed hawk Buteo jamaicensis)

-Typically larger than Accipiter, but much smaller than Golden or Bald eagles
-More straight posterior
-More narrow opening in sheet of bone between eyes (circled)
-Nasal a "triangular oval", more open and clean

(https://skullsite.com/skullpage/buteo-jamaicensis-red-tailed-hawk/)

Accipiter
(Pictured is coopers hawk Accipiter cooperii)

-Wider and larger opening in between bone sheet that separates eyes
-More rounded posterior
-Nasals tend to vary across Accipiter, not as evenly shaped

(https://skullsite.com/skullpage/accipiter-cooperii-coopers-hawk/)

In the process of removing a lot of young coconut palms from under our large coconut palm, some duck bones were unearthed.

Judging by the petite size (and a bit of hopeful bias) I initially thought they could be mallard (Anas platyrhynchos).
However, this was disproved almost immediately, ruled out by the sternum. I new mallards had wider xiphial areas (circled) than a handful of other waterfowl (Muscovy ducks, many geese, and swans, etc.), but I didn't realize just how wide. Not all mallards have the posterior lateral processes (in rectangle) connected to the xiphial area like this reference from the Ohio Virtual Museum, but they're all close. Certainly not a fit for the unknown sternum.
This would hold true for all Anas species, which eliminates them and leaves the two more likely options; a Muscovy Duck (Cairina moschata, specifically Cairina moschata var. domestica) or Egyptian Goose (Alopochen aegyptiaca).

(from https://virtual.imnh.iri.isu.edu/Osteo/View/Mallard/580)

So I got out Muscovy and Egyptian Goose bones for comparative analysis.

First lets start with the sternum.

The Egyptian Goose has a very broad xiphial area (circled) compared to my two Muscovy sternums (larger male, smaller female) and the unknown sternum. The Egyptian Goose sternum in general seems to be wider than the Muscovy and unknown, so it's looking to just be a petite Muscovy duck.

But then I went to the humerus.

(Male Muscovy duck is seen here)
In the square box is an indent known as the capital groove. The unknown humerus and Egyptian Goose humerus both seemed to be more dramatic than the Muscovy. Now I'm considering if this is a goose, not a duck.

On to the pelvis.

Circled on all pelvises is the ischiadic foramen, the opening (foramen) in the ischium of the pelvis. The humerus didn't convince me the unknown was a goose, but this pelvis is getting me there. The foramen of both the male and female ducks is larger, with an almost second foramen extending from the first. I have used such comparisons in my identifications before, so now I'm quite sure this unknown is actually an Egyptian Goose!

And now here comes the tarsometatarsus.

Uh oh. As I went into my box of goose bones to get the tarsometatarsus I immediately realized something was off. Was the unknown bone broken? When I got out the Muscovy tarsometatarsus, however, I realized that no, it was in fine shape. Dirty, yes, but not broken. Egyptian Geese apparently have very long tarsometatarsus, and this unknown bone was not that. And so this becomes a cautionary tale of the inherent randomness in nature, as well as the issues with using features very susceptible to ossifying and changing shape with age.

The unknown is most certainly a Muscovy.

The largeness of the foramen and vague difference in the humerus (which I struggle to find myself now reflecting after a few days) are just not strong enough to trump the wideness of the Egyptian Goose sternum, and, most of all, the size of the tarsometatarsus.
So how do we know what is actually reliable to determine as an identifiable trait?

I am not professional trained by any stretch. I have no formal education in what I do. Not until maybe a year into my self teaching did I buy a proper comparative osteology book, Osteology for the Archaeologist by Stanley J. Olsen.
However, even trained professionals use unreliable identification measures subject to the same issues with what I did with the foramen.
I learned somewhat early on into my studies that professionals often use palatal structures in identification, but that always seemed imprecise to me. I never bothered to study the bottom of bird skulls of IDing, and when people ask if that's an important view I'd say for some people, but I don't find it necessary. And, upon getting my first proper comparative osteology book, I realized I wasn't unjustified in my assumption. From Olsen's Osteology for the Archaeologist:

"It must be pointed out that there is some individual variation in this palatal complex, not only among bird groups, but also regarding the age of individual birds within these groups For instance, in the young of some gulls, crows, and hawks, the anterior margin of the pterygoid becomes detached from the rest and fuses with the palatine. These palatal types must be considered as of taxonomic value only when used as part of the diagnosis which is based on other osteological characters as well."

In short, things that can easily be subject to changes with age can be used for identification as a supplement, but certainly not alone. I personally think I'll retire using the shape of the ischiadic foramen to diagnosis species within a group, though I still intend to use it to differentiate between family groups I never encountered a problem with that thus far, but I suppose time will tell if that's reliable. But there is a much bigger different between a tiny coot ischiadic foramen than the ischiadic foramen of any waterfowl, even if the individuals experience variance.
I've also had issues with using pneumatization patterns for ID, which makes sense. Most bones as far as I'm aware tend to ossify or have changes in ossification with age, and therefore something as delicate as tiny holes in the bone would surely be subject to morphological changes with age. Younger ducks, I have found, tend to have more pneumatization on the bottom of the sternum than older ones. Which makes sense when you think about how many vertebrates ossify more with age.

Ultimately, I think only using one or two traits on one or two bones can always lead to issues, even if they don't experiences the issues discussed above. A well rounded look, exploration and analysis of whatever morphological features you have seems to be a good plan to make the more through ID possible.

I can't express how insanely grateful I am to of found a white ibis (Eudocimus albus) skeleton.
This post will have more photos than those uploaded in my observation. Because white ibis are MBTA protected, I wasn't able to collect it, but I was able to do a set up sufficiently similar to what I do at home to photograph the skeletal elements to try and capture their measurements and morphological features.

I'll be more than happy to define all the terms I use, and correct any I might have misused.

Coracoid, ~4.4, 4.5 cm at longest point.
Ventral veiw.

Scapula.

Furcula (wishbone).

Humerus, ~10 cm.
Left humerus, posterior view.

Left humerus anterior view, right humerus posterior view.

Sternum.
~8.4 cm, 8.8 cm including anterior-most part of sternum, the manubrium.
Ventral view.

Dorsal view.


Emphasis on pneumatization

Lateral view, with coracoids, scapulas, humerus, and wishbone still articulated.

Emphasis on still articulated sternal ribs.

About two feet away, I found the pelvis and some vertebra, and about half a foot from there, the tarsometatarsus, and a few inches away from that the tibiotarsus.

Pelvis, ~8.6 cm.
Dorsal view.

Lateral view.

With tarsometatarsus and vertebra.
Ventral view.

Ventral, with focus on pubis.

Dorsal view.


Lateral view.

Tarsometatarsus (~6.1 cm, posterior view) and vertebra.

Tibiotarsus, ~11.5 cm.

Lateral views.



Emphasis on pronounced outer cnemial crest.

Emphasis on distal end.

And that's that! The associated observation has some more photos, including feathers, but many are the same.

Like how I can't properly express how grateful I was so find this, I also can't properly articulate how humbled I was. I spend hours going through observations of bird bones on iNaturalist, using hundreds of photographs and illustrations for reference from books both online and physical, museum and college collection databases, figures from scientific papers, shared photos from taxidermists, curators and collectors, anything I can get my hands on. I have a decent avian bone collection, consisting of countless Muscovy ducks, several chickens, a couple of feral pigeons, a collared dove, a monk parakeet, European starling, turkey and peacock.

And even with all of that, I was still tripping up and confused. I changed my ID 4 times, back and fourth between shorebirds and white ibis. Some specific features threw me, like the very strong transverse processes on the immediately post-acetabular vertebra (circled) that I am familiar with in shorebirds (comparison is a Glaucous Gull from https://virtual.imnh.iri.isu.edu/Osteo/View/Glaucous_Gull/664), but in general I just felt clueless and bumbling.

The most important thing I think I learned that day wasn't any specifics about white ibis or great blue heron skeletal structure (more on the heron later, maybe tomorrow), of which I learned a great deal, but that I am still vastly ignorant. Every bird in my skeletal collection was found and cleaned by me or me and my sister, with the exception of the turkey, which I bought because I was having difficulties grasping their bones. It's incomplete, I don't have complete turkey skeleton money, but it has helped insurmountably. And the fact that the white ibis bones have also helped me understand so much, far more comprehensively than Olsen's Osteology for the Archaeologist or the Smithsonian's photographs ever could, was a rude awakening as to how stunted I am by not having access to physical references. Illustrations and pictures are helpful, but no substitute for the real thing. The ibis skeleton just felt so foreign, even though I've seen pictures and illustrations of them and even IDed some before.

There's obviously no easy solution to this, there's no way I could legally argue getting a collection permit for these things and the only museum that would have those reference materials near me is about 7 hours away by car. But I can hope to keep exploring and encountering new incredible finds. Studying avian osteology without many ways to ascertain physical bones to study sure isn't easy, but fortunately I like a challenge.

(In other news of personal osteological break throughs, I have finally found a photographic reference on an aningha pelvis. I'm sure a physical one would still blow my mind, but after only seeing illustrations for years it is still super impressive to see an actual photo.)