Appearance

Snowy Plovers have 10 functional primaries, 14-15 secondaries (including 3-4 tertials), and 12 rectrices. Plovers are diastataxic (see Bostwick and Brady 2002) indicating that a secondary has been lost evolutionarily between what we now term s4 and s5. Wings are moderately pointed and tail is short and squared. Geographic variation in appearance moderate worldwide. The following plumage-aspect descriptions pertain to the North American subspecies C. a. nivosius; see Systematics: Geographic Variation for variation in up to five other recognized subspecies in South America and Eurasia. No geographic variation in molt strategies reported, except as related to timing of molt in Southern Hemisphere populations, coinciding with opposite day-length regimes.

Molts

Molt and plumage terminology follows Humphrey and Parkes (1959) as modified by Howell et al. (2003, 2004). Snowy Plover exhibits a Complex Alternate Strategy (cf. Howell et al. 2003), including complete prebasic molts, a partial preformative molt, and limited prealternate molts in both first and definitive cycles (Bent 1929, Palmer 1967a, Oberholser 1974, Prater et al. 1977, Cramp and Simmons 1983, Pyle 2008; Fig. 6). Molts follow a "Northern Hemisphere Strategy" as defined by Pyle (2008). Definitive plumage aspect is often attained following the first prealternate molt but following the second prebasic molt in less-advanced individuals.

Prejuvenal (First Prebasic) Molt

Complete, May-Jul, at or near natal site. First appearance of pin feathers in primaries by d 4. By d 7, pin feathers are prominent in primaries, secondaries, scapulars, upper back, and along sides; and by d 10, feathers are breaking from sheathes on crown, scapulars, neck, and sides (Boyd 1972). Juvenal primaries and secondaries are still growing and down is still apparent on head when birds begin flying at about 1 mo of age.

Preformative Molt ("First Prebasic Molt" Of Previous Authors)

Partial, Jun-Dec, sometimes extending as late as Mar, primarily on non-breeding grounds. Includes most to all body plumage, usually some proximal secondary coverts, and sometimes 1-3 tertials, but no other wing or tail feathers. Onset is dependent on hatching date. In earliest hatchlings begins by late Jun, in latest hatchlings not until mid-Sep.

First And Definitive Prealternate Molts

Limited, Feb-Apr, primarily on non-breeding grounds. First (Definitive) and subsequent prealternate molts similar in timing and extent although first molt averages less extensive and may also average later in timing. Cramp and Simmons (1983) report that this molt can include most to all body feathers, some secondary coverts, most tertials, and some to all rectrices in European populations, but in North American populations prealternate molts appear limited to head and breast feathers (Pyle 2008). Reports of prealternate molt beginning as early as Oct in California may have been based on males with well-marked basic plumage (see Definitive Basic Plumage, below).

Definitive Prebasic Molt

Complete, Jul-Nov, primarily on or near breeding grounds but can complete on non-breeding grounds. Primaries replaced distally (p1 to p10), secondaries replaced proximally from s1 and s5 and distally from the tertials, and rectrices probably replaced distally (r1 to r6) on each side of tail, with some variation possible (GWP).

Plumages

Following based primarily on detailed plumage descriptions in Ridgway (1919), Bent (1929), Palmer (1967b), Oberholser (1974), Johnsgard (1981), Cramp and Simmons (1983), Hayman et al. (1986), Rosair and Cottridge (1995), Paulson (1993, 2005), and O'Brien et al. (2006); see Prater et al. (1977) and Pyle (2008) for specific age-related criteria. Sexes show similar aspects in juvenal and formative plumages, slight dimorphism in definitive basic plumage, and moderate dimorphism in alternate plumages.

Natal Down (May-Jul).

Completely covered by down. Upperparts pale buff or creamy buff mixed with light gray. Crown, back, rump, and wings distinctly spotted with brown and black; underparts pure white. Distinct white band encircles neck, black line extends behind eye (Boyd 1972).

Juvenal (First Basic) Plumage (Jun-Aug).

Crown, nape, mantle, rump, ear coverts, and foreneck (patch) drab or light drab with pink-buff edgings on tips of feathers. Forehead, hindneck, and all of underparts white. Inner secondaries mostly white, primaries dusky with white shafts and an increasing amount of white on inner feathers. Up to outermost 3 pairs of rectrices white; remainder progressively darker inwardly, with central pair grayish brown to sepia, sometimes with paler tips.

Formative Plumage (Sep-Mar).

Aspect similar to that of Juvenal Plumage but formative feathers with less-extensive or no pink-buff edging. Contrasts between worn juvenal and fresher formative feathers visible in wing, can be useful in separating first-cycle and definitive-cycle individuals. Primaries and rectrices also average narrower and more worn than in Definitive Basic Plumage.

First Alternate Plumages (Mar-Aug)

Aspect generally similar to Formative Plumage. In males, front part of crown, ear coverts, lores (sometimes), and foreneck black or mixed black and white; remainder of crown and nape orange-buff, often mottled white. In females, front part of crown, ear coverts, foreneck vary from drab to mostly black, except for a few brown feathers; remainder of crown and nape usually drab (occasionally light buff); lores white (GWP). See Definitive Alternate Plumage for further information on sex determination. Duller head plumage along with wing and tail characters described above (Formative Plumage) can be used to separate First from Definitive Alternate plumage aspects.

Definitive Basic Plumage (Sep-Feb)

Aspect similar to that of Formative Plumage but wing feathers uniformly fresh and primaries and rectrices broader. Males often show some dusky or blackish to forehead, auriculars, and/or sides of breast typical of breeding-plumage aspect (see Alternate Plumages). Other males and most females lack any indication of breeding aspect.

Definitive Alternate Plumages (Mar-Sep)

Similar to First Alternate Plumage but males with more extensive and blacker patches in forehead, auriculars, and sides of breast. Females with these areas averaging duskier and often mottled with some blackish feathers. Females show narrower forehead band (typically < 4 mm) than males (typically > 4 mm), with some definitive-alternate females and first-alternate males showing intermediate widths (Pyle 2008). Uniform wing feathers and broader and fresher primaries and rectrices can be used to separate definitive from first alternate individuals.

Individual variation in plumage of Kentish Plovers has been studied in Eurasia. Males with larger breast bands (badges) had earlier nests than those with smaller ones, and males with larger badges also had larger clutch volumes suggesting that badge size might signal male quality and affect either the female’s investment in eggs or male success in territorial defense (Lendvai et al. 2004b). However, there was no evidence that birds with artificially enhanced breast bands had improved chances of obtaining a mate for second clutches after experimental removal from initial clutches. Males with enhanced badges spent less times fighting conspecifics than control males (Lendvai et al. 2004a).

Male Kentish Plover have longer flank feathers than females but there was no evidence that inter-male variation in these feathers influenced mating times; enlarged flank feathers may be an adaptation to parental care rather than a sexual ornament (Lendvai et al. 2004a). It has been hypothesized that males have longer flank feathers because they incubate at night when temperatures are cooler than during daytime when females incubate (Kis and Székely 2003).

Bare Parts

Bill

Black.

Iris

Dark brown.

Bare Skin

Eyelids black.

Legs And Feet

Slate gray to black, occasionally dull yellowish or pinkish.

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