Mexican Chickadee

The Mexican chickadee is about 13 cm (5.1 in) long and weighs 9 to 12 g (0.32 to 0.42 oz). The sexes have the same plumage. Adults have a black head from the level of the eyes up and a black hindneck, both with a faint bluish gloss. The have pure black cheeks, chin, throat, and upper breast, and the rest of their face is white. The black on the chin and throat is conspicuously more extensive than on other chickadees, stretching onto the upper breast. Their back, scapulars, rump, and uppertail coverts are deep olive gray or mouse gray, with the strongest olive on the rump. Voice: The Mexican chickadee's song is "a series of short abrupt phrases peeta peeta peeta". Its principal calls are "a high buzzy sschleeeer" and "a high, buzzy, and hissing tzee tzee shhh shhh".