Sharp-shinned or Coopers? (1 Viewer)

[Accipiter91]

Hello, I do not have many birds of prey on my life list and am trying to fix that problem. Unfortunantly I can not tell the difference between the Cooper's (Accipiter cooperii) and Sharp-shinned (Accipiter striatus) hawk. My guide says that the main difference in the two is size, but I am not able to judge the difference between the two without having one of each side by side. Can anyone give me any field marks that I can use to tell the two species apart in the field? Thanks and have a nice day.

Bob​

 

[IanC_UK]

Dont know either bird but this guide may help

Coopers Hawk

Sharp Shinned Hawk

 

[Ade George]

Ceasar wrote this on one of the other treads.

"Well, it possibly was one, then again------------? I wouldn't add it to your count though. Try picking out some field marks next time. Was tail rounded or squared? Did it have bars, etc? Any color or markings on the belly and under the wings, etc. Head color? Eyebrow marks? Overcast skies make things a bit tougher. Keep looking for field marks and say them out loud as you ID them to check against your field guide. Practice makes things easier.
Good Birding,"

The only Coopers I have had was flying with a Red tail so the size was easy to get. I hope this helps.

Ade

 

[lockbreeze926]

Cooper's are indeed notably bigger - but probably the best mark is that a Cooper's in flight shows a rounded tail, Sharp-shin shows a square tail. Coop also has a broad(ish) white band at the end of the tail, but this is often hard to see in flight

Cooper's also has a pale nape; a larger head (bit subjective,that) and - many say - a fierce rather than surprised "expression", although that may also be regarded as a bit impressionistic. Naturally, if the legs are seen well, those of the Cooper's are not "sharp" - i.e. very thin - but that is more obvious from a side view, since head-on they do look narrow.

There are also differences in the streaking/barring, but I find these useful really only for photos.

 

[newarkbirdguy]

I would add another thing to what the other folks have commented.

In flight, both birds have a flap-flap-flap-glide style of flight, common in accipiters. However, the sharp-shinned hawk's wingbeats are just too fast to count unless you're really focusing just on that (4-5 per second). A cooper's wingbeats are enough slower that you can count them (maybe 2-3 per second). I'm just throwing out those numbers on frequency off the top of my head, but it could well be that someone has studied this and have more accurate data. But as a quick rule of thumb, if the wingbeats look really quick it is more likely a sharpie.

Andy - Newark, CA

 

[talon_dfa]

Plenty of good info available at websites and field guides, but no magic formula.

There is no substitute for experience.

At first, you will have difficulty immediatly recognizing the bird as a raptor.

With more experience, you will know it is a raptor, but not know which "group" (buteo, falcon, accipiter, harrier etc).

With more time/experience, you will quickly know that you are looking at an accipiter.

With enough practice, you will be the one explaining to others why that "streak" that went by too fast for anyone to get binos on it was a male sharpie or that speck in the sky is a female coop.

So read every book you can find, but get out in the field and watch those raptors. There are lots of behaviour clues that you can learn that will not come from a book.

FYI some more wing & weight data on North American Accipiters (contrary to some older books, there is no overlap in size between Sharpie & Coop).

Coop:
http://www.birdwatching-bliss.com/coopers-hawk.html

Sharpie:
http://www.birdwatching-bliss.com/sharp-shinned-hawk.html