Hello everyone - long time no post! So yesterday morning I found myself standing in front of my car trying to decide whether to go back in the house and get my new D700 for the big 5 minute drive to Starbucks. I finally stop procrastinating, figure what the ****, so I run back to the house, grab my new D700 and step back outside just in time to see this hawk swoop by my front door and land in a tree right in front of my house, not 20 feet from were I was standing! Had the 70-300 VR on the body (wish I had taken my D300s! ugh!) and was able to snap this one pic before the raptor took off. The whole episode, from bird flying by, landing, and taking off again, was maybe 10 seconds.
The pic is nothing to write home about, very soft, heavily cropped . . . but I thought the timing was hilarious. 5 more seconds either way and I would have completely missed this bird. And I've NEVER seen a hawk in my neighborhood prior to this morning.
Question - can anyone ID this hawk? Is it a Coopers Hawk?
Thanks!
Brian
Hi Brian- The yellow eye on this bird suggests a young one. Young Coopers and Sharp-shinned are best separated by looking at the pattern on the breast. This is not available here of course. Peterson mentions a notched or square tail for the Sharp-shinned and your bird certainly has that. Your bird looks fairly slight too, which fits. Coopers are really quite big- about 3-4x the mass of a Sharpie. Females are bigger than males though in both species, and the degree of dimorphism is high so this confounds the comparison.
We have some hawk experts on BPN that I hope will make a pronouncement.
Thanks so much for the feedback John! I thought the black horizontal banding on the tail was a dead giveaway for a Coopers, but I guess not. I bit more complicated than that as i turns out.
I know the photo doesn't have any reference point for size, but if it helps this bird was WAY bigger than a raven - I'm thinking head to tail about 14 to 16 inches, give or take.
Brian
Ravens are huge compared to Cooper's Hawks, which as mentioned are generally much larger than Sharpies (note the sexual dimorphism though). Ravens are about 3 times the mass of a Coopers, 1.5 times the length and have almost double the wing span. The length you give is good for a Coopers but a bird that size would be dwarfed by a Raven.
Absolute size is very hard to estimate accurately because our brains factor in distance as well (I assume you didn't see a Raven next to your bird?). If we perceive distance incorrectly we can think things are much bigger or smaller than they really are. Every year in Antarctica I have people swear to me they just saw a penguin "about 6 inches long swimming in the water". It takes some gentle convincing that in actual fact they are 3 times that length or more.
This bird is giving me heartburn. John is correct about the eye color, so we're dealing with a juv. As John also pointed out, underparts are very helpful for this ID, but we're not going to get them unless Photoshop has a new super-duper feature that allows you to rotate pictures front to back! Head shape can also be helpful, but it appears that this bird is leaning forward so I don't know if we can make an accurate judgment. I've even had banders tell me that relative foot size is useful, but that's blocked too. (Hey, are you intentionally messing with us? ;) )
Brian, is it OK for me to a) send this around privately to some very sharp birders that I know and b) post this to the ID-Frontiers list-server? I won't start at (b), but if I send it to a half dozen good hawk people and end up with a split opinion, I'd like to "upgrade" to a larger set of birders. Hopefully it's a straightforward ID to raptor people and that won't be necessary, but just in case...
If you've never seen ID-Frontiers, it is a list-server run by Will Russell. To see a sample of the level of discussion, you can go to:
John - EXCELLENT points you make re: percieved size and estimating distance. Also, thanks for educating me on the size of Ravens - I had NO idea they were that big! I figured a wee bit bigger than crows - NOT!
Paul - goodness, of COURSE you can forward my pic to anyone/any list-server. It's intriguing to me that this identification business isn't always as straight forward as I had assumed. "course, my quick snap was obviously designed to hide all the pertinant parts of the bird. See, this is really a test to see how sharp all you raptor folks are! hee hee!
:p
Brian
I agree with all the comments about this being a Sharp-shinned rather than a Cooper's hawk, for all the reasons given already. Common ravens are indeed huge. Just the other day I watched a Raven harrassing a Red-tailed hawk, and it was about 10% bigger than that - and Red-tails are bigger than Coopers or Sharpies. According to Sibley a Coopers hawk is 16.5 x 31 in., while Common raven is 24 x 53 in.Here is an image I took a few years ago - I would not normally consider the remote possibility of posting this on BPN, but it at least illustrates the size of a Raven compared to a Rough-legged hawk at the same distance.
Thanks Richard. Here's another "take" on how big Ravens are! The image was made with my 500/4 and these birds were a fair way off. The raven looks big not because he's much closer to me than the owl.
I received 5 separate replies from top flight (pun intended) birders, all of whom have counted and/or banded raptors. They are in total agreement that the bird is a Cooper's Hawk, though for quite a combined set of reasons. I summarized them below:
TAIL
Rounded tail shape (mentioned by several).
Obvious pale tips to retrices (tail feathers).
Rounded corners to the retrices, contributing to the Cooper's round-tailed look.
Outer retrices noticeably shorter than central retrices.
HEAD & NECK
Tawny head.
Rufous tones on upperparts, especially the hindneck.
Hindneck appears that it may have hackles.
Large head, small eye/head ratio, and a relatively forward placed eye.
OTHER
Large white spots on the back.
Relatively long tail and short primary projection.
Quote: "A good rule of thumb is that there are 3 black tail bars visible past wing tips in Coop, usually 2 in Sharp-shinned."
Apparently long legs.
Quote: "Also, in gauging how far down the toes that peek out from behind the tail are, I'd say Cooper's. They have longer legs than do Sharpies, which would be much more obvious if the bird was facing us. I can envision this bird showing quite a lot of leg below the belly, should it be facing the photographer."
That's quite a bit of detail, with some of it being a real learning experience for me.
Now if I can just get a good shot spread tail shot of that selasphorus hummingbird that showed up at my feeder this morning... :p
Thanks so much Paul for taking the trouble here. The Coopers ID certainly fits with Brian's comments about the relatively large size of the bird. I do see the roundedness of the tail caused by the shorter outer rectrices too. I agree with Roy- the bill looks dainty, as does to me the whole head. Maybe a small male? I must say I'm surprised that your top-flight crew did not have a go at sexing the bird too!
I guess I now have egg on my face, my ID was wrong, and now that the ID features of Coopers have been so clearly pointed out, with hindsight it's a no brainer. However, many of the features are rather "soft", and impressions rather than measurable ID points - except for the statements that the outer retrices are noticeably shorter than central retrices and "A good rule of thumb is that there are 3 black tail bars visible past wing tips in Coop, usually 2 in Sharp-shinned.", which are both more objective and independently verifiable. Neither of these points are specifically mentioned in the standard field guides used by most birders, although the illustrations in Sibley illustrate the tail bar point very nicely. Tail feather tips can become damaged or worn, and many images of Coopers show what appear to be squared off tails. I didn't know about the usefulness of the number of tail bars, and that seems to be a relatively objective field mark that I will take note of in the future.
My face looks like I had a soft-boiled egg this morning too Richard! Not to worry, it comes with the territory. I have been moderating this forum from the beginning and the Cooper's/Sharp-shinned question has I think been by far the most contentious over this time, but ultimately in a positive, constructive way, like this thread. Quite honestly for me the important thing is to get across to people the method and logic of identifying birds- kind of like story about teaching people to fish rather than just giving them food. The correct ID, although nice to get right, is not that important to me. Someone almost always gets it in the end and the process towards the correct ID is the interesting part. But to each his/her own. I am a professional seabird scientist so as long as I get the ID of my study species correct, that's what matters to me!
As I am batting 0 for the last few IDs, I am retiring from IDing anything but American Robins for a period to be decided entirely by me!!!!!!
I have some thoughts on species systems, super-species, sister species, names, and related issues, which I will expound on later.
John, I'm still not convinced. :o They are very hard to differentiate, but I always go by if it looks like a Sharpy, Coops or whatever then it is a Sharpy, Coops etc. I think some people rely way too much on Sibleys etc when making an ID. I've seen tiercel pacific coast Goshawks (Langaii) that you would identify as female coops unless you knew for certain where that bird came from. This of course applies to lots of birds not just raptors.
Roy, you might find this abstract to be interesting. They did a scientific study on Sharp-shinned vs. Cooper's ID error rates at one or more actual hawkwatches. The take-away point is:
"Among juvenile hawks (n= 940), we found the greatest misidentification rate for male Cooper's hawks (23% of the 156 males were identified as sharp-shinned)"
So even well trained hawk counters are having ID, particularly with male Cooper's.
I'm not sure about this study, but I had read about this same type of thing being done before where banding stations are located "upstream" of the hawkwatch. A trapped bird identified in the hand is released, the bander radios the counters to let them know a bird is coming, and the counters then ID the bird. Just as this study showed, the greatest error rate was with the mis-identification of male Cooper's Hawks.
FYI, personal comments from highly experienced people I know have been that adult male Cooper's Hawks are even tougher than the juveniles.
Sorry I'm a bit late joining this thread, but thought I'd share a useful link to "16 Ways to Tell Sharp-Shinned Hawks from Cooper's Hawks" created (and copyrighted) by Don Freiday of the Cape May Bird Observatory. I found this a very helpful contribution to this commonly-debated question. Go to http://2.bp.blogspot.com/_xS-DecqOeG...+accipiter.jpg
Can someone ID this hawk? Is it a Coopers Hawk?
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