Visual ID of American vs. Fish Crow...

How does that make you feel? I'm posting a few crow photos from today with the hopes of generating some discussion as to everyone's comfort level in using visual characteristics in separating these species in a semi-vagrant setting (Ontario).

Set/bird #1:

Set/bird #2 (plus an OOF bird) -

What say you?! I'll write my (100% honest and not influenced by whatever anyone else says) opinions in a few days...

Right now, mega migration is unfolding!!

PS - if you want to know more on these species, check out the holy grail link here: 

http://www.birds.cornell.edu/crows/FishCrow.htm

UPDATE:

Radio-silence leads me to believe that no one is comfortable with visually ID'ing crows... Here's a few more pics from today (one day after the pics above) - if you want to try some more before commenting! 

(I think there are 3 birds in this series, but I may have included a fourth) 

And one more bird:

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Edit #3 - 

Here's my take.... 

The fieldmarks for birds in flight are generally not reliable... It may be that there are differences in size/shape in the flight feathers between adults & first year birds (anyone have pyle handy? mine is buried)....

The moe "swept back" the wings are, the harder it is to assess the appearance of P5 vs. P4, P6 & P9...

I can find "one off" pictures of both AMCR & FICR that appear to show exactly what that species SHOULD NOT show... (both primaries and bill structure) 

Therefore I think it'd take 10+ photos (with different postures) to properly assess any differences in primary ratios...

Here's my thoughts on the above birds:

First five photos: 

A key problem here is all my photos show the bird with the wings swept back, which seems to favour FICR appearance regardless of species... 

However, in each photo, P5 seems to have no interest in looking like a finger (or at all longer than P9) and the bill is very hooked, so I'm inclined to identify it as a Fish Crow (with the full disclaimer I'm not really worried if I'm wrong, and am happy to adjust going forwards as we get better information on these birds). 

Second set of five: 

This bird, and the previous (first set of five) were a flock of five crows that flew past... I managed to get a series of two only... This bird spreads out a bit more, and I'm inclined to say the same features apply regarding the primaries (P5 looks more like P4 than it does P6 - aka not a finger)... The wing spread is a little better in trying to say that P9 is roughly equal to P5, although you can see that each wing looks a bit different, highlighting how awful this is to try with photographs..

(the bill is hard to see)

One other interesting element is that the out of focus crow in the background of two of these images is clearly showing P10-6 in both shots (with the third and final below) with P5 MIA... 

So in summary, I had a flock of 5 crows - that all looked odd to me - so I took pics.... I now have ~30 photos of three birds, and none show any features either strongly against FICR, or strongly pro AMCR, so I'm inclined to say the flock was a group of FICR... So if you're like me, and you enjoy trying to identify every single bird you see regardless of circumstances - it's an interesting thought/conclusion... 

IF you like enjoying your bird observations and NOT making mistakes when identifying birds, then this process probably seems insane...

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The last 12 photos (of 5 different birds, I think) - were all taken the next day, as I tried to get some new reference material to test these ideas on... I suspect they're all American Crows.... The vast majority of photos seem to show a semi or strongly-pro AMCR feature on first glance... Some images showed features that seemed to align with Fish Crow, however once I tried another mark (e.g. P5 vs. P9) it was more in line with AMCR... Check out some markups of the origional bunch:

Long story short:

The marks aren't definitive - photos can be misleading - take 15-20 photos of a bird in flight, and then you'll have a chance of being more confident, but not totally confident, if you care. 

Oh, and context is huge as well (I had 5 birds together in a FICR-plausible time/place, when peak AMCR migration has passed, which gave me a really weird vibe - after watching for these things fairly steadily since 2011).