Black-capped Chickadee

Description

The black-capped chickadee has a black cap and "bib" with white cheeks. Its underparts are white with buff-coloured flanks. Its back is unstreaked and greenish grey, and the tail and wings are slate grey. It has a black beak and legs, and dark brown irises. Males and females are generally similar, although males have a larger bib. They can also be distinguished based on a combination of weight and tail length. Tarsus length does not significantly differentiate sexes. Males have a wing length of 63.5–67.5 mm (2.50–2.66 in), a tail length of 58–63 mm (2.3–2.5 in), a bill length of 8–9.5 mm (0.31–0.37 in), and a tarsus length of 16–17 mm (0.63–0.67 in). Females are on average slightly smaller, with a wing length of 60.5–66.5 mm (2.38–2.62 in), a tail length of 56.3–63 mm (2.22–2.48 in), a bill length of 9–9.5 mm (0.35–0.37 in), and a tarsus length of 16–17 mm (0.63–0.67 in). Both sexes weigh 10–14 g (0.35–0.49 oz). Juveniles are visually similar to adults but with fluffier plumage. Although range can generally be used to separate them, the black-capped chickadee is very similar in appearance to the Carolina chickadee. The edges of the wings are somewhat paler than the Carolina chickadee, and the bib of the black-capped chickadee has a "messier" border than the Carolina chickadee. The most reliable way to distinguish the two species is by vocalizations. Black-capped chickadees have a slower, hoarser, two-part song, whereas Carolina chickadees have a three-part song. Black-capped chickadees are also somewhat similar to mountain chickadees and boreal chickadees. Mountain chickadees can be distinguished by a distinct white stripe above their eyes, and boreal chickadees have a brown cap as opposed to the black cap of the black-capped chickadee.

Range & habitat

Black-capped chickadees are non-migratory and can be found throughout much of North America. They range from western Alaska, through southern Yukon and throughout the Canadian provinces, from British Columbia in the west to the Maritimes and Newfoundland in the east. The distribution continues into the United States, with its range extending to northern California in the south-west, through northern Nevada and New Mexico, continuing through the midwestern United States to New Jersey. It can also be found in the Appalachian Mountains at higher elevations. In British Columbia, the black-capped chickadee is absent on Vancouver Island, the Gulf Islands, Haida Gwaii, and parts of the Sunshine Coast, where it is replaced by the chestnut-backed chickadee. They are typically most common at elevations below 750 m (2,460 ft), although they have been known to occur at up to 3,200 m (10,500 ft). Black-capped chickadees inhabit wooded areas, including both coniferous and deciduous forests, urban parks, willow thickets, and suburban areas. They do not vary their habitat between breeding and non-breeding seasons, although in the winter irregular bird migration and dispersal may occur.

Adapted from Black-capped chickadee on Wikipedia, used under CC BY-SA 4.0.