Another bird captured on my NC big year attempt in 2014. Of course this is a bird I have seen many times considering I grew up in the Northeast and have birded up there since. The Black-capped Chickadee is common up North, and probably more common in NC than most think, but ID is difficult because it is so similar to Carolina Chickadee. However, the guesswork is taken out if you head up to the summit of Clingman's Dome, the most reliable place in NC to see and hear them.
Although some people claim that Carolina Chickadees can also give the 3 note "hey, sweetie" song, if you hear it on the top of Clingman's Dome in breeding season, you can be pretty sure it is a BC Chickadee. This bird pictured here was singing away.
One visual field mark is that BC Chickadees have more white edging on the tertials, like this bird.
Some field guides also mention differences in the white pattern on face and nape, but I would be hard pressed to ID based on that. Probably the cutest bird in North America and an outsized personality to boot.