The black-capped chickadee has a black cap and "bib" with white sides to the face. Its underparts are white with rusty brown on the flanks. Its back is gray and the tail is normally slate-gray. This bird has a short dark beak of 8–9.5 mm (0.31–0.37 in), short rounded wings 63.5–67.5 mm (2.50–2.66 in), a tarsus of 16–17 mm (0.63–0.67 in) and a long tail at 58–63 mm (2.3–2.5 in). Total body length is 12–15 cm (4.7–5.9 in), wingspan is 16–21 cm (6.3–8.3 in) and body mass is 9–14 g (0.32–0.49 oz). Sexes look alike, but males are slightly larger and longer than females. Although range can generally be used to separate them, the black-capped chickadee is very similar in appearance to the Carolina chickadee. The black-capped is larger on average but this cannot be used reliably for identification. The most obvious difference between the two is in the wing feathers. In the black-capped chickadee, the wing feathers have white edges that are larger and more conspicuous than those of the Carolina chickadee. The latter is often mistaken for black-capped chickadees with feather dystrophy which sometimes affects the appearance of the primary feathers making them look slimmer, a phenomenon caused by illnesses such as fatty liver disease in malnourished birds. Overall, the Carolina appears slightly paler colored whereas the flanks of the black-capped can appear to have a trace of off-yellow or rusty coloration. Also,...Learn more about Black-Capped Chickadee