Appearance

Adult Black-capped Chickadee, Ithaca, NY, 13 February.

Fledgling Black-capped Chickadee, Seattle, WA, August.

Adult Black-capped Chickadee, wing detail, Ithaca, NY, 29 January.

Fig. 4. Black-capped Chickadee: annual cycle of breeding and molt, Massachusetts.

Molts And Plumages

Juvenal Plumage

Black-capped Chickadees have 9 functional primaries, 9 secondaries (including three tertials), and 12 rectrices. Geographic variation in appearance slight (see Geographic Variation) and no geographic variation in molt strategies reported. Molt and plumage terminology follows Humphrey and Parkes (1959) as modified by Howell et al. (2003, 2004). Black-capped Chickadees exhibit the Complex Basic Strategy (cf. Howell et al. 2003), including complete prebasic molts and a partial preformative molt but no prealternate molts (Smith 1991; Pyle 1997a, 1997b).

Prejuvenal (First Prebasic) Molt

Jun-Aug, in the nest. For detailed description of molt pattern see Breeding – Young Birds – Growth and Development. Similar to adults in appearance, but cap duller and feathers softer and shorter (Bent 1946).

Preformative Molt ("Prebasic I Molt" Of Pyle 1997 And Previous Authors)

Partial, Jul-Oct. Body feathers, most wing coverts, and occasionally 1-2 tertials replaced; 1-4 outer greater coverts retained in about half of individuals.

Definitive Prebasic Molt

Complete, typically Jul-Sep. Duration 2-3 months (Smith 1991). Males and females do not differ in feather growth rates (growth bars measured on left outer rectrix), however, higher-ranking males had feathers that grew faster than lower-ranking males (Mennill et al. 2003a).

Natal Down

Sparse gray natal down.

Juvenal, Formative, And Definitive Basic Plumages

Post-natal plumages similar except as described below. Based on detailed descriptions in Ridgway (1904), Oberholser (1974), and Smith (1991); see Pyle (1997) for specific age-related criteria. Sexes show similar aspects in all plumages, except as noted, below.

Definitive basic plumage of spring and summer adult Parus atricapillus atricapillus: Entire pileum, and all except the lateral portion of the hindneck, uniform deep black; back, scapulars, middle and lesser wing coverts plain olive gray, passing into more buffy gray on the rump and upper tail coverts; wings and tail dusky slate or dull blackish slate; greater secondary coverts and secondaries broadly edged, and primaries narrowly edged, with pale gray or grayish white; rectrices edged with light olive-gray, or nearly ash gray, these edgings becoming white on outermost ones; chin and whole throat black, the feathers near posterior margin of this black area more or less conspicuously tipped with white; sides of head and neck white; underparts of body white, the sides and flanks tinged with buff. Adults in autumn or winter similar but more richly colored (especially the buffy areas) due to veiling of feather fringes; this veiling wears off by late winter producing grayer spring plumage.

Individuals in Juvenal and Formative Plumage differ in having narrower and more pointed (juvenal) outer rectrices and primaries and less white to the outer web of the outer rectrix (Meigs et al. 1983, Pyle 1997a). In Formative Plumage, retained juvenal primary coverts (and retained outer greater coverts in about half of individuals), browner and more worn, contrast with replaced grayer median and inner greater coverts; in Definitive Basic Plumage all wing coverts are uniformly grayer, the primary coverts with broader gray edging (Pyle 1997a, 1997b). Skull completes ossification in fall of hatching year, usually by mid-Oct.

Black-capped Chickadees are sexually monomorphic to human observers but spectral analysis of plumage regions reveals hidden sexual dichromatism (Mennill et al. 2003a). Male Black-capped Chickadees have brighter white and grey regions and greater contrast between adjacent light and dark regions than do females. Additionally, males have larger black bibs than females (Mosher and Lane 1972, Otter and Ratcliffe 1999, Mennill et al. 2003a). Females can detect these subtle plumage differences between males (Woodcock et al. 2005) and correlative data show an association between male plumage traits and male reproductive success (Doucet et al. 2004).

Bare Parts

Bill And Gape

Bill black. Gape yellow in fledglings; pink inside bill in adults.

Iris

Dark brown.

Legs And Feet

Legs and feet bluish gray (dusky in specimens).