
LESSER SCAUP (continued) 
Age Determination of Females 
1. Upper Wing: 
(a) All of the following: tertials are smooth or 
lightly frayed to a rounded tip. Greater coverts 
are wide and rounded over the tertials but rarely, 
if ever, flecked. Middle coverts are usually 
lightly flecked. Flecks are small and often con- 
centrated at the edges of individual coverts ------ Adult 
(b) All of the following: tertials are invariably frayed 
to pointed tips. Over the tertials, greater coverts 
are narrow, unflecked, and usually frayed towards a 
point. Middle coverts are usually plain, but occa- 
sionally covered with small flecks that are concen- 
trated at the edges of individual coverts --------- Immature 
RINGNECKED DUCK 
Sex Determination of Adults 
The tertials of males are shiny greenish black and bluntly 
pointed, The tertials of females are similar but less shiny, greenish 
brown and broadly rounded. The middle and lesser coverts of males are 
brownish-black; those of females, blackish brown. On adult males, the 
two most proximal gray secondaries are usually edged with white. On 
females, one or both usually is not. Males are often flecked on the 
lesser coverts near the body. Females are rarely flecked. 
All of these differences are either slight or not wholly con- 
sistent, and accurate sex determination is quite difficult. Because a 
number of immature males appear female-like, sex determination of 
immatures is not completely reliable. 
Age Determination 
Tertials of the adult plumage are usually slightly curved and the 
tips are rounded. Juvenile tertials are pointed, straight and much 
frayed. The greater coverts of adults are broadly rounded over the 
tertials. Those of the juvenile plumage are narrow, and often frayed 
to a blunt point, over the tertials. The middle coverts of adults are 
broad, rounded and smooth. Those of the juvenile plumage are narrower, 
somewhat squared and often rough. 
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