296 BAY, SEA OR DIVING DUCKS 



Steller's Eider 



Polysticta stelleri 

 (pol-i-stick-ta, stel-e-ri) 



Colour Plate No. 23. Downy Young No. 34. 



SCIENTIFIC NAME 



Polysticta, from Greek, polys, meaning many, much, and sticte, meaning spotted, 

 varied; stelleri and the vernacular name "Steller's," in honour of George Wilhelm 

 Steller (1709-1746), a German zoologist and traveller; naturalist on Bering's ill-fated 

 voyage to the sea which bears his name. 



COLLOQUIAL NAMES 



Not known. 



DESCRIPTION 



ADULT MALE. WINTER PLUMAGE: Head and side of upper neck, shiny white; 

 tuft of peculiar plush-like feathers on back of head and a patch in front of eye, 

 yellowish green or light olive green; two black spots flanking green tuft on back 

 of head; black ring around eye; chin and throat, iridescent blue black, usually 

 narrowly connected in front to blue-black collar around middle neck; lower foreneck, 

 white; bill, dull greyish blue, lighter at tip; eye, dark brown to red brown. Body. 

 Back, glossy blue black, centrally; sides of foreback, white; rump, black; longer 

 scapulars, iridescent blue black, striped with white, shorter scapulars, white; black 

 spot on sides in front of folded wing; chest and sides, cinnamon buff, deepening 

 to orange brown on breast, centre of breast, sepia; flanks and belly, blackish; feet, 

 dark blue grey, with dusky webs. Tail, long and pointed, dark brown; upper and 

 under coverts, black. Wings. All coverts, white; outer secondaries, with blue-black 

 speculum, tipped with white behind; inner secondaries and tertials, long and sickle- 

 shaped, inner webs silvery white, outer webs blue black; primaries, brown; lining, 

 mostly white; axillars, white. 



ECLIPSE PLUMAGE: The moult into eclipse occurs in July and August, when the 

 striking colours of the head and neck are replaced by brown feathers, with only a 

 trace of the blue-black collar left on ,the hindneck. The back becomes dull black, 

 and the showy scapulars become brown. The wings and underparts remain as they 

 were and are moulted only once. 



AUTUMN PLUMAGE: The moult out of the eclipse into full winter plumage 

 follows much the same sequence as that described under the American Eider. 



ADULT FEMALE. Head and neck, dusky brown and brownish buff, darkest 

 on crown and hindneck, palest and most faintly variegated on cheek, at base of bill, 

 around back of head and around eye (some do not show lighter colour on cheek, 

 or at base of bill); bill, dusky blue; eye, dark brown. Body. Back, scapulars, chest, 

 sides and rump, rich dark brown, with paler edges to feathers; breast, very dark 

 brown, blackish on belly; feet, same as those of male. Tail and upper and under 

 coverts, dark brown, upper coverts tipped with paler brown. Wings. Lesser and 

 middle coverts, dusky brown, with greyish tips; greater coverts, dusky, with broad 

 white tips; secondaries, with broad white tips and speculum as in male but duller; 

 inner secondaries and tertials, sickle-shaped, dusky brown on inner webs, dark blue 

 on outer webs, with pale grey-blue central streak on each feather; primaries, dark 

 brown; lining, white; axillars, white. 



