Appearance

Mourning Doves have 10 functional primaries, 12 secondaries (including three tertials), and 14 rectrices. Geographic variation is slight. The following plumage descriptions pertain to the widespread eastern North American subspecies Z.m. carolinensis; see Systematics: geographic variation for variation in up to four other recognized subspecies in western North America, Florida, and Mexico. No geographic variation in molt strategies has been reported, although year-round breeding of southern populations likely results in differing timing and (perhaps) extents of molts; study needed.

Molts

Molt and plumage terminology follows Humphrey and Parkes (1959) as modified by Howell et al. (2003, 2004). Mourning Dove appears to exhibit a Complex Basic Strategy (Howell et al. 2003), including complete prebasic molts and a complete (occasionally incomplete) preformative molt but no prealternate molts (Fig. 7).

Prejuvenile (First Prebasic) Molt

Complete, Mar-Sep, in the nest. Development of Juvenal plumage described in detail by McClure (1943), Hanson and Kossack (1957b, 1963) and Holcomb and Jaeger (1978). Primaries emerge from skin at 2 d, rectrices at 3 d, secondaries at 4 d, body feathers at 5 d, crown and head feathers at 6 d; primaries and their coverts begin to emerge from sheaths at 7 d, upper breast and crown at 8–9 d, head and back (except on neck at junction between head and back), ventral tracts and belly at 10–11 d. Completion of feather coat under wings, belly, and elsewhere from 12–15 d. Flight feathers fully grown by about 30 d (Taylor 1941).

Preformative Molt

Complete, primarily Jul-Oct (but can be protracted and may occur year-round in southern populations that can breed year-round). Location of molt variable: can be on or near the breeding grounds, at stopover sites, or on or near the wintering grounds, and can suspend for migrations between localities (Thompson 1950, Ault et al. 1976, Armstrong and Noakes 1983). Includes all feathers in approximately 94% of individuals (Pyle 1995), contrary to Tyler (1932) who stated that only body plumage and rectrices are replaced. Begins at about 30–40 d age and is complete in 100–120 d on average (Moore and Pearson 1941, Taylor 1941, Quay 1951, Jenkins 1955, Swank 1955, Allen 1963, Peterson and Brown 1974, Haas and Amend 1976). Primaries molt in numerical sequence from innermost (P1) to the outermost (P10). Greater primary coverts are replaced a bit prior to their corresponding primaries, thus the last outermost covert is lost at about the time P9 is dropped (Jenkins 1955, Wight 1956, Wight et al. 1967, contrary to Pearson and Moore 1940). Primary molt may then resume as late as Mar. Pyle (1995) found that 6% of Mourning Dove specimens had retained 1-2 juvenal secondaries among S4-S6 during arrested preformative molt. No birds found with retained outer primaries, but this can occur in other species of Columbiformes and may occur occasionally in Mourning Dove.

First And Defintive Prealternate Molts

Very likely do not exist. Speculation on the occurrence of such a molt (Mirarchi 1993a; cf. Pyle 1997) likely based on year-round prebasic molts. No other Columbiformes, including strongly sexually dimorphic species, have confirmed prealternate molts (Frith 1982, Goodwin 1983, Rowan 1983).

Definitive Prebasic Molt

Complete, primarily Jun-Nov (Jenkins 1955, Sadler et al. 1970, Haas and Amend 1976, 1979, Bivings and Silvy 1980) but possibly may occur year-round in southern populations that can breed year-round (cf. Acosta and Torres 1984). Duration of molt reported by Allen (1963) to average 112 d; however, this molt can last 140 d (137 for females, 144 for males) in N. and S. Carolina (reanalysis of data from Haas and Amend 1976, 1979 by Johnson 1989), 140–150 d in Missouri (Sadler et al. 1970), and 181 d in Texas (recalculation following Pimm 1976 of data in Bivings and Silvy 1980). Time span for molt can also vary seasonally (typically slower during years of poorer food resources) so above data should be interpreted accordingly. Males reportedly can begin molt 1 d (Sadler et al. 1970) to 5–6 d (Johnson 1989) earlier than females; but progress more slowly than females, finishing one to a few days later. No incomplete definitive prebasic molt recorded (Pyle 1995), but retained definitive secondaries (as occurs during preformative molt) may occur in occasional individuals (Pyle 1997).

Plumages

See Ridgway (1916), Roberts (1955), and Oberholser (1974) for detailed plumage descriptions. Sexes are similar in juvenal plumage but differ in formative and definitive basic plumages. Color names and numbers below follow Smithe (1975).

Natal Down

Squabs covered with cream colored (54) down (Hanson and Kossack 1957b, Mirarchi 1993a); down also described as white (Nice 1922, Tyler 1932), and yellow (Wetherbee and Wetherbee 1961).

Juvenal Plumage

May-Aug. Sexes alike. Grayish brown, paler and more buffy below than formative and definitive plumages; feathers of foreneck, chest, scapulars (and sometimes interscapulars), and wing coverts have pale buffy or whitish terminal margins; no black subauricular spot as in later plumages; primaries and secondaries brownish and distinctly but narrowly edged paler on inner web (Ridgway 1916, Whitman 1919). Darkly mottled juvenal plumage resembles pattern of fallen debris and may be adaptive in concealing nestlings (Hitchcock and Mirarchi 1986, Grand and Mirarchi 1988, Mirarchi 1993a).

Formative Plumage

(Sep-following Aug). Very similar to definitive prebasic plumage, described below. Individuals in formative plumage cannot be aged after all greater primary coverts and secondaries have been replaced. However, because molt can be protracted, suspended, and occasionally arrested, first-cycle birds can be aged (at times through Jun of 2nd yr) by showing paler tips and edges of inner webs of remaining juvenal primaries or secondaries (Petrides 1950, Wight et al. 1967, Wood 1969, Pyle 1997). Birds in which primary molt has progressed to at least P6 may be accurately sexed by differences in the color of their throat/breast, crown, and outer 3 rectrices (Reeves et al. 1968, Menasco and Perry 1978, Cannell 1984), as in definitive basic plumage. Some males may be reliably identified by plumage before this but females cannot be confirmed by plumage alone (Pyle 1997). Both sexes may average less rose coloration to formative plumage than typically found in definitive basic plumage (Pyle 1997).

Definitive Basic Plumage

(Sep-following Aug). Plumage consists of grayish brown feather coat on back, wings, and tail. One black spot or short streak is present behind eye, and one behind and slightly below eye. Numerous black spots present on both wings. Underparts buffy becoming paler on throat and on undertail coverts. Tail long and graduated with central rectrices (R1) longest (13–15 cm long) and outermost rectrices (R7) shortest, about one-half that length (J. D. Sullivan pers. comm.). R1 same color as back but grayer, sometimes darkening terminally; R2 grayer (nearly pure gray) with a fairly distinct dusky bar across middle portion of inner web; R3 similar but dusky (or black) bar more distinct, extending on to outer web (bar shaped like an inverted V), and apical portion of feather paler gray; R4-R5 with broader black bar extending entirely across both webs, the gray of apical portion passing into grayish white terminally; R6 similar but apical portion mostly white and R7 similar but outer web entirely white. Inner webs of primaries and secondaries lack paler tips and edges, as found in juvenal feathers.

Males have distinctive bluish gray cap and nape and pinkish rosy hue over face, throat, and breast; neck feathers tinged with pink iridescence. Newly emerged feathers on head and neck of males have olive tipped edges leading to drabber coloration during the non-breeding season. Tips wear away during the winter to reveal brighter plumage by the breeding season (Sullivan and Mirarchi 1999). Females have olive gray cap and nape, olive brown face and throat, and tan breast; neck feathers usually tinged with olive green iridescence, although some pink iridescence occasionally occurs. Males may often show whiteness on outer 3 rectrices whereas females may usually show whiteness on outer 1-2 feathers (photo in Mirarchi 1993b), but this criterion may not be reliable with all populations and should be used in conjunction with other sex-specific characters. Occasional individuals show intermediate coloration and are difficult to sex (Menasco and Perry 1978, Schulz et al. 1995) and may be males in formative plumage or very old females (Pyle 1995).

Aberrant Plumage Coloration

Reviewed in detail by Mirarchi (1993b) and outlined below. All forms of albinism (after Mueller and Hutt 1941, Pettingill 1985) more rare in columbids than in other birds. No specimen of total albinism reported for Mourning Dove, but incomplete, imperfect, and partial forms of albinism have been reported. Incompletely albinistic forms have white bodies, red-pink eyes, and off-white or whitish-spotted wings. Imperfectly albinistic forms show dark eyes, pale bill and feet, and plumage either gray-white (non-phaeomelonic, loss of brown pigment) or fawn brown (non-eumelanistic, loss of gray or black pigments) in color. In both forms, plumage shows signs of rapid wear and abrasion, feather tips and edges quickly worn away leaving only shaft. Partially albinistic forms generally involve whitish primaries (often symmetrically) but occasionally individual feathers on head or other body parts (REM).

Bare Parts

Bill And Gape

Bill dark neutral gray (83) in all ages; gape dark neutral gray in squabs, vinaceous (3) in immatures, vinaceous to deep vinaceous (4) in adults (REM).

Iris

Fuscous (21) in squabs, dusky brown (19) to dark grayish brown (20) in immatures and adults (REM).

Bare Skin Or Wattles On Head Or Neck

Bare skin around eyes light neutral gray (85) in squabs and immatures; turquoise blue (65) in adult male and turquoise green (64) in adult female, particularly during breeding season. Cere glaucous (80) in squabs, becoming pale neutral gray (86) in immatures and pearl gray (81) in adults (REM).

Legs And Feet

Olive gray (42) in squabs, deep vinaceous in immatures, geranium (12) to geranium pink (13) in adults (REM).