A Broken Wing in my City (1 Viewer)

[coohm]

Dear all bird lovers,

I am seeking ideas on the phenomenon I come across these days.
From facebook, I see
Bird wings are broken apart,
and this is the third pieces I have seen.

People are swearing this is made by human.
But I am assuming if it is naturally happened.
I have no idea if any raptors have this behavior.

can any of you help?

https://scontent-hkt1-1.xx.fbcdn.net/v/t1.0-0/p526x296/123682760_1550230628496843_6223965340427169236_o.jpg?_nc_cat=107&ccb=2&_nc_sid=825194&_nc_ohc=2VazkDaJiOUAX-vR89q&_nc_ht=scontent-hkt1-1.xx&tp=6&oh=332a5c8de0967227e71a254efac2398f&oe=5FCAB7D9

 

[nartreb]

You can see that who/whatever did this ate the meat off the upper part of the wing, and discarded the rest.
It also appears that the shoulder joint area has been crushed, exposing some marrow (the reddish-brown grainy stuff is marrow) and leaving a splinter hanging off the end of the bone.
That doesn't look like knife-work to me, so I'll go with non-human.
I don't know if your local birds of prey have the beak strength to crush the bone like that (around here, the hawks that take birds are mostly quite small) , so my suspect list would start with a dog.
(It's also possible that a hawk killed the bird and then a dog got hold of the wing afterward.)

 

[Nutcracker]

(It's also possible that a hawk killed the bird and then a dog got hold of the wing afterward.)

That sounds very plausible to me :t:


The wing looks like it is from a white domesticated pigeon.

 

[nartreb]

The pigeon (I agree with Nutcracker, looks like a white pigeon wing) might also have simply flown into a reflective window, or been struck by a car, bus, or train. (Something about the tiles in the photo remind me of a train station.) It's even possible a car could completely sever the wing and crush the shoulder. Then something (dog, most likely) came along, finished the job of detaching the wing if needed, cleaned the meat off the bone and gnawed on the proximal end a bit.

 

[Nutcracker]

The pigeon (I agree with Nutcracker, looks like a white pigeon wing) might also have simply flown into a reflective window, or been struck by a car, bus, or train. (Something about the tiles in the photo remind me of a train station.) It's even possible a car could completely sever the wing and crush the shoulder. Then something (dog, most likely) came along, finished the job of detaching the wing if needed, cleaned the meat off the bone and gnawed on the proximal end a bit.

That's less likely; a dog wouldn't pick the bone clean of meat so effectively, and wings don't break off just from window or vehicle collisions. It looks very like a falcon's or hawk's prey remains in all respects except for the crushing. So I think your first guess of a raptor followed by a scavenging dog is the best.

 

[RafaelMatias]

I'd suggest this is made by an avian predator. Pigeon bones are really fragile and any chewing would result in visibly chewed/crushed/obliterated ends and other bits (and that does not happen here). The wing is missing some other feathers also that have been plucked (not chewed off).
An urban Peregrine Falcon would be my first suggestion (with a pigeon being eaten somewhere on a building top and then the wind blowing the wing away, making it falling on the street).
Large gulls and skuas are able to do something just like that (but to smaller birds, thrush sized): they can swallow the whole bird, leaving the wings hanging out of the bill and then regurgitating both clean wings (still attached to each other by the furcula or split) after the body detaches (this happens with seabirds almost as large as pigeons, such as Bulwer's Petrels); but gulls and clearly skuas are obviously not contenders here.
So, I'd say the culprit is an urban raptor/falcon/hawk of some kind.


PS: and welcome to Birdforum!