(thayeri)
Note: "Kumlien's Gull" is considered here to be Iceland x Thayer's hybrid and is in the hybrid section. See this page for a note on taxonomy and a proposed Thayer's/Kumlien's/Iceland scoring system.
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Thayer's Gull (thayeri) Note: "Kumlien's Gull" is considered here to be Iceland x Thayer's hybrid and is in the hybrid section. See this page for a note on taxonomy and a proposed Thayer's/Kumlien's/Iceland scoring system. |
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IMAGES:
DESCRIPTION:
First Cycle
Second Cycle
Third Cycle
Adult
THAYER'S GULL (22-25"; 50-55") thayeri
| BILL SHAPE: short, thin, and straight; about 3-4x eye diameter; little gon angle; curve of culmen is gentle | ||||
| HEAD SHAPE: smooth and often very rounded, somewhat dainty or dove-like; sometimes w/ sloped forehead | ||||
| WING EXTENSTION: slightly longer than bill length | ||||
| POSTURE/HABITS: slightly heftier than Iceland, smaller than Herring | ||||
| FIRST CYCLE | SECOND CYCLE | THIRD CYCLE | ADULT | |
| BILL COLOR: | solid black; some w/ flesh base to lower mandible | pale flesh w/ variable dark tip; some may be mostly dark | variable flesh to yellow w/ dark tip or subterm band; may show some gon spot | pale yellow, may have greenish tone w/ brighter tip; gon spot red to orange-red, small and flat, not extending to cutting edge; rarely w/ dark mark |
| LEG COLOR: | dark pink | dark pink | dark pink | dark rose pink |
| IRIS/ORB RING: | dark | usually dark | usually as adult | iris usually dark; may be honey or even yellow; orb ring |
| HEAD: | covered w/ thin diffuse g-b streaks; aurs often solid; pale on aur edge, upper nape, near bill and on throat | white w/ fine light streaking on crown and aurs; heavy blotching often around nape to breast sides | as adult but w/ more extensive streaking over head, neck, and upper breast | light streaks on crown and aurs, paler and browner than on smithson; extensive thick blurred streaks on lower nape to breast sides |
| UNDERPARTS: | breast fairly uniform pale g-b, diffusely streaked or splotched; belly uniform and slightly darker; undt covs barred | variably smudged, especially on belly; undt covs lightly barred | white; some splotching from breast may extend to belly | white |
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PRIMARIES (folded): |
dark g-b w/ pale crescents of feather tips, sometimes worn off by late winter | variable gray w/ pale crescents | as adult, but w/ smaller A-spots | A-spots evenly sized or slightly decreasing; A7 slightly larger than eye; A10 same size or slightly smaller than eye |
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PRIMARIES (in flight): |
outer webs of outer Ps dark, inner webs light, producing a striped effect; pale window on inner Ps; silvery pale from below w/ thin dark trailing edge to outer Ps | as juvenile but w/ pale webs nearly white; inner Ps nearly white; thin dark trailing edge to outer Ps from below, otherwise quite white | ... | limited black on Ps; huge terminal mirror on P10; large mirror on P9; black confined to outer webs and subterm bands on P5-9; large white tongues on P6-8; pattern much fainter from below, showing dark gray subterm bands only; gray undersides show little contrast |
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SECONDARIES (in flight): |
like Ps, outer webs dark and inner webs light, but w/ pale fringe; silvery pale from below | washed g-b outerwebs and pale inner webs w/ pale fringe; whitish from below | ... | adult gray w/ white trailing edge about ½ bill length |
| TERTIALS: | usually a little darker than covs, lighter than Ps; solid g-b w/ variable pale subterm marks and pale tip; some w/ pale notches along sides | med g-b w/ extensive white marbled tips and fringes | adult gray; may have trace of g-b | adult gray w/ white crescent about 3/4 bill length |
| GREATER COVERTS: | completely barred or spotted g-b and white, appearing checkered | white w/ irreg fine brown barring or marbling | adult gray; may have trace of g-b | adult gray |
| LESSER & MED COVERTS: | like scaps, but w/ smaller anchors, appearing neatly checkered | white w/ irreg fine brown barring or marbling | adult gray; may have trace of g-b | adult gray |
| SCAPULARS: | pale w/ large g-b subterm anchors, giving a checkered look; anchors may be larger and more solid, giving a scaled look | usually mixed w/ adult gray; some w/o adult gray, appearing like a muddied version of 1W | adult gray | adult gray w/ white crescent about 1/3 bill length |
| BACK: | dark anchors larger, making most of feather dark, giving scaled look | adult gray mixed w/ g-b; some w/ little adult gray, looking pale and muddy | adult gray | adult gray is med light; darker than smithson, lighter than California |
| RUMP: | heavily barred | paler; lighter barring | white | white |
| TAIL: | large broad dark band, contrasting w/ upperparts, w/ pale fringe, barred outermost webs and barred bases to outer few retrices | gray tail band still darker than rest of back; bases of retrices whitish | white w/ irreg broken subterm band | white |