You bet, Cynthia!  Very clear tail feather length and fat legs.  That 
flat look of the head in the last photo with its crest slightly raised 
is also a good ID factor when it appears.  Sharpies do not have that.

Sharpie versus Coop is often a difficult call, but sticking to the 
basics helps to clear up most questions.  In soaring flight way up over 
your head, as hawkwatchers often see them, none of those indicators can 
usually be seen, so it's often a lot harder.

Jane
(Shoreham)

On 10/16/2018 9:26 AM, Cynthia Crawford wrote:
> On Mon, 15 Oct 2018 21:45:07 -0400, Jane Stein <[log in to unmask]> wrote:
> 
>> Heh!  Sharpie vs Cooper is the single most difficult ID among raptor
>> enthusiasts, so no shame if you got it wrong-- if you did!  Actual
>> raptor experts might have a different take than Zach and I do.
>> Experienced hawkwatchers have been known to literally come to blows over
>> the ID.  But... I doubt it.  I'm an enthusiast of many years, not an
>> actual expert!
>>
>> I wouldn't rely on the "bug-eyed" look since it depends so much on the
>> angle of the bird and the picture and the familiarity of the observer
>> with these guys.  But the tail feather length in such a clear pose as
>> you got (not always the case in photos in the field!) is truly
>> definitive, as is the thickness of the legs, when you can see them.
>> Banders have wildly different bands for Coops and Sharpies, and once I
>> saw those, I was totally convinced of the dramatic difference between
>> the 2 species, not just variation from individual to individual.  Pretty
>> much everything else is more impressionistic, so not really reliable for
>> ID, only as contributing factors that can very easily lead the observer
>> astray.
>>
>> One other factor to consider is that although there are more Coops
>> around than there used to be, Sharpies still outnumber them by quite a
>> bit. So Sharpie is the default ID for a smallish Accipeter, and an ID of
>> Cooper's needs more confirmation from observable characteristics like
>> leg size and tail feather lengths.
>>
>> Resist the ebird police!  But do let us know here if you get interesting
>> feedback, positive or negative, OK?
>>
>> Jane
>> (Shoreham)
>>
>>
>>
>>
>>
>>
>> On 10/15/2018 8:25 PM, Cynthia Crawford wrote:
>>> On Mon, 15 Oct 2018 09:01:54 -0400, Jane Stein <[log in to unmask]> wrote:
>>>
>>>> Agreed, Zach.  The tail feathers, despite the broad white tips, are the
>>>> main tip-off-- all the same length.  In this tail position, Coop's has
>>>> noticeably shorter outer tail feathers.  The relatively small, bug-eyed
>>>> head is another.  Chest streaking is harder to judge, for me anyway,
>>>> because it's not that consistent from bird to bird.
>>>>
>>>> It does look large and chesty for a Sharpie, but that may be the lack of
>>>> context from this close, since it's impossible to tell from the photos
>>>> how large those branches and trunks are.  And a big female Sharpies can
>>>> be pretty close to male Coop's in size.  Lastly, I'd add this bird's
>>>> rather thin, stick-like legs, although there's only a glimpse of them in
>>>> the one pic that shows the bird lifting off from its branch, as
>>>> contrasted with the Coop's thick, sturdy-looking legs.  The Coop often
>>>> chases prey on foot, whereas the Sharpie rarely does, so the difference
>>>> in the evolution of leg size actually has a purpose.
>>>>
>>>> Jane
>>>> (Shoreham)
>>>>
>>>>
>>>> On 10/15/2018 7:35 AM, zach schwartz-weinstein wrote:
>>>>> Sharpie, with the messier reddish streaking, bug-eyed appearance, small
>>>>> head and bill, and even-length tail feathers.  Nice photos.
>>>>>
>>>>> On Mon, Oct 15, 2018 at 7:33 AM Veer Frost <
>>>>> [log in to unmask]> wrote:
>>>>>
>>>>>> Gorgeous, thank you, hope someone will know.Veer Frost, Passumpsic
>>>>>>
>>>>>> On October 14, 2018 at 9:55 PM, "cynthia crawford"  wrote:Got some
>>>>>> pretty good pictures- pretty sure this is a Cooper's. Opinions
>>>>>> welcome:
>>>>>> https://www.flickr.com/photos/33836164@N03/albums/72157700879431161
>>>>>>
>>>>>> Cynthia Crawford
>>>>>>
>>>>>> *Creature Kinships and Natural Affinities*
>>>>>> Animal and Nature Paintings, Portraits and Prints
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>>>>>> www.creaturekinships.net
>>>>>>
>>>>>> www.creaturekinships.com
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>>>>>> EVEN MORE PHOTOS: https://www.flickr.com/photos/33836164@N03/
>>>>>> Castle & Court Music for Harp:
>>>>>> http://galleries.creaturekinships.com/?page_id=59
>>>>>> BLOG: http://creature-kinships.blogspot.com/
>>>>>>
>>> Thanks Zach and Jane- appreciate your thoughts. I noticed the thin legs/feet especially, but felt the head was a bit large. Perhaps because of the extended neck photo. I wasn't aware of the "bug-eyed" feature for Sharpies, so that's helpful. I think I will report it as a sharpie and see if I get corrected by the ebird "police". ;).
>>>
> Gotcha, Jane. Will report id the "ebird police" come after me. ;). Meanwhile, here's a very sure Cooper's Hawk: https://www.flickr.com/photos/33836164@N03/albums/72157702301051484. I think the tail tells all here...or maybe it's a tall tail? ;)
>