Carolina chickadee

Adults are 11.5–13 cm long with a weight of 9–12 g, and have a black cap and bib with white sides to the face. Their underparts are white with rusty brown on the flanks; their back is grey. They have a short dark bill, short wings and a moderately long tail. Very similar to the Black-capped Chickadee, the Carolina Chickadee is best told from it by the slightly browner wing with the greater coverts brown (not whitish fringed) and the white fringing on the secondary feathers slightly less conspicuous; the tail is also slightly shorter and more square-ended.
In winter, Carolina Chickadees live in flocks of two to eight birds and defend areas against other flocks. Dominant birds in these flocks establish breeding territories in the summer that were part of the winter flock's range.
The pair bond between a male and female Carolina Chickadee can remain intact for several years.
The oldest known Carolina Chickadee was 10 years 11 months old.