Hybrid Carolina X Black-capped Chickadee - Pelee Island

Had this funky Chickadee at Fish Point during my recent stay to the island. There were large numbers of Chickadee's around, and I'd guess I had 100-150 individuals during my visit. Two or three individuals stood out as having a number of Carolina-features, but not measuring up in all areas. Check it out:

Pro-Carolina features... Clockwise from lower left:

Grayish breast contrasts with white cheek

Relatively small and well defined bib

Relatively stubby/small bill

Low contrast flight features

Limited white edging on the tail

Overall grayscale colouration with limited/absent peach on sides

Some critical marks just didn't line up though.. Left to right:

Head often lacked the "circular/rounded" look

Greater coverts contrasting with back

This bird looked somewhat spot-on to "hybrid" Chickadees I found online after some rather extensive searching... The contrasting greater coverts seems like a particular key feature in separating these species and does seem quite intermediate in possible hybrids.

(Interestingly, the Long Point Carolina Chickadee is a little outside my comfort zone, but lets not go there)

Of my 2 or 3 observations, this one really jumped out at me. Interestingly, each one seemed to be a female... Something I can't really confirm with the bird shown in the photos here... But one sighting (also at Fish Point) involved a "normal" Black-capped feeding the suspected "hybrid" - so quite likely a female was involved... I didn't get any photos of that bird, and didn't get quite the same looks to really feel confident about anything - BUT - I was able to record some limited calling with my cell phone. Check it out:

Does it tell us much? I don't really know - I did some listening but it seems like they're capable of any range of calls/dee's/noises... I also worked a fair bit to get these calls out of a reluctant bird, so perhaps it's not an accurate representation of what it would normally do... 

Overall quite a bit of fun though! I'll finish this off with a few more looks at the original bird from Fish Point