Appearance

Sexes alike at all stages. For presumptive phenology, see Figure 5 . No definitive information on molt of North American birds, and little information on plumage sequences or plumages of birds of known age. Information reported for European birds (Cramp 1985) largely conjectural.

Hatchlings

Downy young are cryptically colored, with a grizzled pattern. They have narrowly mottled, hairlike down with a prickly appearance, because filaments are gathered into a point. There are 2 predominant color morphs, gray-and-black or buffy-and-black, with some intermediates. Gray morph <20% in northeast, but about 75% in Caribbean (ICTN, MG).

Juvenal Plumage

Table 4 . Prejuvenal molt completed by mid-Jul. Two main color morphs occur with some intermediates, either buff or gray above, barred with black chevrons. In gray morph, forehead and lores mottled buff, white, and brown; crown streaked black, brown, and white. Patch extending from just in front of eye back around nape is black; feathers edged paler. Upper mantle white, freckled brown. Feathers of lower mantle and back, scapulars, and tertials pale gray, tipped white, with tertials freckled buff; each feather has 1 or more subterminal black crescents. Rump and uppertail-coverts pale gray, mottled buff to variable extent. Central rectrices (R1) pale gray, with dark subterminal crescent. r2–R5 gray, with white on inner web and tip, and black brown subterminal crescent, dot, or streak. R6 largely white. Tail forked, but overall much shorter than in adult. Underparts, axillaries, and underwing white. Remiges as in adult, but gray is duller. Greater and median wing-coverts pale gray, tipped white, with variable amount of subterminal brown or buff mottling. Lesser wing-coverts dark gray, fringed white. As feathers become worn, forehead paler, upperparts with more contrasting dark markings, gray on primaries and tail darker, especially at tips (Cramp 1985).

Basic I Plumage

Few data on Prebasic molt. Apparently occurs on winter grounds in European populations. Forecrown and back-feathers molted early in molt cycle. Molt incomplete. In European populations, part of Juvenal tail and tertials may be retained through at least Dec, and part of Juvenal remiges and primary-coverts retained through Apr or May (Cramp 1985).

Basic I plumage similar to Definitive Basic (adult) plumage, with white-mottled forehead and dark, nearly blackish hindcrown. Bill and feet black. Some black scaling evident on mantle and wing-coverts.

Alternate I Plumage

Prealternate I molt partial, presumed similar to Definitive Prealternate molt (see description of Definitive Alternate plumage, below); occurs during spring.

Alternate I plumage historically referred to as a “ portlandica ” plumage (originally described as a distinct species), characterized by pale gray upperparts, with dark carpal bar on wing, and white underparts as in Basic I, but with black hindcrown extending to nape and encircling eye, and white forecrown, mottled with black. Outer rectrices usually shorter than in breeding adult. Bill and legs usually black, but in some individuals that migrate northward legs and base of bill are orange red (ICTN).

Basic Ii Plumage

No information on Prebasic II molt. Presumed similar to Definitive Prebasic molt (see description of Definitive Basic plumage, below). Basic II plumage like Definitive Basic (adult nonbreeding) plumage with white forehead, but secondaries darker. Outer 5 primaries and coverts still gray brown and worn. Tertials may retain dark centers.

Alternate Ii Plumage

Prealternate II molt partial; presumed similar to Definitive Prealternate molt (see description of Definitive Alternate plumage, below). About two-thirds of 2-year-old birds seen at breeding colonies are indistinguishable from adults, except for dark gray on lesser-coverts (faint carpal bar), and black or largely black bills; few of these birds breed. About one-third have prominently speckled foreheads and dark carpal bars, thus this plumage variable as in other terns (ICTN).

Definitive Basic Plumage

The following molt descriptions are based primarily on data from European populations; North American specimens in molt are scarce in collections. Definitive Prebasic molt complete; begins with inner primaries on breeding grounds when feeding young. Contour feathers (often beginning on forehead) and tail begin molting by mid-Jul and are completed by midwinter. Before all primaries are replaced, a second wave of replacement begins again at P1 by midwinter. A third wave of replacement may also begin by late winter, so some birds arriving at breeding grounds show 3 generations of primaries. Primary molt arrested during beginning of breeding season. At this time, second wave has usually progressed to P6–P8, and third wave has usually progressed to P1–P4 (Cramp 1985). Primary molt also may be interrupted by migration.

Definitive Basic plumage similar to Definitive Alternate plumage, except forehead white (sometimes dotted black); crown white with black markings, which gradually merge with a black patch extending from eye back to nape. Dark outer primaries retained from breeding season are replaced with new paler feathers by early winter. Wear causes these new feathers to darken gradually as breeding season approaches (Cramp 1985).

Definitive Alternate Plumage

Definitive Prealternate molt partial; includes at least contour feathers, rectrices, and inner primaries, although primary replacement probably part of an extended Prebasic molt (see description of Definitive Basic plumage, above).

Forehead, crown and nape (down to upper lores and lower eyelid) black, forming shallow cap on head. Back, scapulars, tertials, and upperwing-coverts pale neutral gray, grading to paler gray on rump and grayish white on uppertail-coverts, not contrasting with color of back. Remainder of head, underparts, axillaries, underwing-coverts, and lesser wing-coverts along bend of wing white; underparts (particularly breast and belly) washed with delicate creamy pink, bleaching to creamy white at tips of feathers. This color gradually fades as breeding season progresses. Rectrices pale grayish white, with indistinct whitish margins; outer web and tip of outermost rectrix (R6) mostly white. Primaries pale silver gray, outer web narrowly edged white (except P10) and inner web broadly edged to tip of feather with white. Outermost 2–4 (usually 3) primaries older and more worn than remaining primaries and appear darker, especially as breeding season progresses. May become grayish black when heavily worn, but usually retain some of original silvery patina. Secondaries pale gray to grayish white; inner web and tip broadly edged, and outer web narrowly edged white (Cramp 1985, ICTN).

Bill And Gape

Bill color (extensively black) is often used in field to distinguish Roseate from closely related terns. Populations breeding in ne. North America develop reddish bill coloration at different times than populations breeding from Caribbean south (Cormons 1976). Northeastern birds arrive at breeding sites with all-black bills, but show slight red base by midincubation, and bill about one-third to one-half red when chicks fledge, changing to black in Aug. Caribbean adults arrive at breeding sites with mainly black bill, but by time of egg-laying (usually mid-May) basal two-thirds of bill is reddish orange, becoming almost all orange during chick-feeding; only rarely do birds with black bills breed (Shealer and Saliva 1992). Mouth-lining is dark red. Black bill in immatures.

Iris

Blackish brown.

Bare Skin On Head

None.

Legs And Feet

Cyanotic purplish gray when hatching, becoming black by age 2–3 d. Black persists until following spring, becoming dull orange with Alternate I plumage. Adults have bright red orange legs and webs when breeding; dark brownish black during remainder of year.