Raptor ID by Behavior of other Birds?

[floraphile]

12 Nov 2020 Baldwin co AL

From a great distance, I saw a large raptor fly into the midstorey of a fairly leafless tree.  The bird's coloring was a mix of splotchy brown & light.  My first thought was immature Bald Eagle, but it could easily have been a Buteo sp., as It was hard to ascertain its size.  He was definitely a large & sturdy fellow.   The thing that struck me most was that the tree top was loaded with EUST & they did not even budge.  So I'm fairly certain it was not Mr. (or Mrs.) Cooper.  

Edited November 12, 2020 by floraphile
typo

[Aaron]

Don’t think we’ll be able to ID the raptor as most are brown and splotchy ? Though, a bald eagle would appear much larger than starlings and should be ID’able from quite a distance. 
Any chance this was an Osprey? Osprey mainly feed on fish and I would suspect they’re not much of a threat to starlings. 
 

To go off on an aside as this reminded me of a study, you can somewhat estimate the size or threat of an unseen predator based on how many ‘dees’ a chickadee adds after its “Chick-a-dee-dee” call. Numerous studies have found significant results that the more the predator is a threat to the chickadee (smaller birds like Merlins, Pygmy owls etc) the more ‘dees’ will result in its alarm call. Similarly, less ‘dees’ mean less of a threat and would be used for predators such as an eagle or maybe even a coyote that wouldn’t go after a chickadee. 

I have a photo of a Cooper’s hawk and a ECDO in the same frame about 20 feet apart and have seen multiple times ECDO do absolutely nothing in the presence of a Merlin as swallows and other birds go crazy.  Not sure if they were being cocky or if that they saw the raptors and deemed them not a threat as they lost the element of surprise. 
Anyways, whatever the bird was, the starlings deemed it not a threat to them so it might be reasonable to rule out a few species, but who knows. 

[floraphile]

Hi, Aaron.  Thank for the info!  I'm pretty sure it wasn't an Osprey.  It didn't have that pigeon head.  lol.  

[nonamecreek]

My guess is red-shouldered. Here in Central TX they hunt behind my home regularly. When one, or a mated pair, come in my feeder birds: cardinals, sparrows, finches, WWDO, MODO, starlings, etc. just go about what they were doing before arrival. A coop of sharpie? Scatter city, except, maybe, on occasion, a WWDO will just sit still, mid-city tree, and the accipiter misses it. Dumb dove or dumb raptor?

[Avery]

Correct me if I'm wrong, but don't buteo's not hunt wild birds? I mean, I wouldn't be surprised if a hungry red-tail decided to pluck a chicken from someone's yard, but I think only accipters, falcons, owls, and eagles will hunt other birds. So, if your bird was a buteo, maybe the other birds recognize it as not being a threat? Talk about birding under pressure!

[nonamecreek]

8 minutes ago, Avery said:

Correct me if I'm wrong, but don't buteo's not hunt wild birds? I mean, I wouldn't be surprised if a hungry red-tail decided to pluck a chicken from someone's yard, but I think only accipters, falcons, owls, and eagles will hunt other birds. So, if your bird was a buteo, maybe the other birds recognize it as not being a threat? Talk about birding under pressure!

I'm told by many others that red-shouldereds prey on birds often in many parts of the US. I've not seen such here in Central TX. Don't know about AL. I have seen red-tailed take a dove on the ground.

[AlexHenry]

I generally think of Buteos and Aquila Eagles (Golden Eagle) as mammal specialists. While I think of Falcons and Accipiters as bird specialists. 
 

That being said, there are definitely exceptions - these are not really rules, but more general guidelines. For example Broad-winged Hawks (buteos) will also eat snakes and birds, and Northern Goshawks (accipiters) eat Snowshoe Hares. 

Also I often see birds freak out when a Turkey Vultures flies over.

So I don’t think it’s very safe to ID a raptor based on the reaction of prey items. It’s an interesting point though and definitely worth paying attention to, and could be informative to an extent, just not really enough to confirm an otherwise unidentified bird.

[Aaron]

I’ve seen many instances as well, where smaller birds attack much larger raptors than that of which would pay any attention to them. Or at least are bothered by their presence. 
Crows, ravens, blackbirds, magpies, and swallows I’ve seen all go after buteos. Chickadees will mob a great horned owl, and I’ve seen some small birds go after eagles. 

Either way, maybe birds have evolved to detect the traits typically associated with and shared between birds of prey and thus recognize them as potentially dangerous. So they’re just being safer than sorry? Maybe in the same way as we know a coyote probably won’t kill us, but if we see one we generally try to avoid it or scare it off. 
Not sure.

Still don’t know what those starlings were doing though!