
BUFFLEHEAD (continued) . 
2. Wing Length: 
(a) 159 mm. or shorter ----------------------------- 3° 
(b) 160 mm. or longer ----------------------2---- --- Immature Male 
3. Greater Coverts: 
(a) Frayed at tips over secondaries, tertial 
coverts often appear narrow with brownish 
fraying at their tips -------------------------- Immature Female 
(b) Smooth and rounded over both secondaries 
and tertials ----------------------------------- 4 
4. Tertials: 
(a) Appear short, straight, often with pointed 
fraying that shows traces of brownish ---------- Immature Female 
(b) Appear long, drooping, broadly rounded at 
ends, may’ show fraying but not brownish -------- Adult Female 
HOODED MERGANSER 
Only a dozen known age wings were available for study. However, 
approximately 35 specimens were obtained for which nothing was known, 
but which seemed to separate readily into adult females, adult males, 
and immatures, of both sexes. From the combination of this material, 
the following suggestions are postulated. 
Sex Determination of Adults 
Adult males have shiny black, unfrayed tertials with longitudinal 
white-striped and lightegray middle coverts. Adult females have shiny 
black tertials with longitudinal white stripes, which while long and 
tapering (as in males), have slightly blunter tips. All the middle 
coverts are a relatively blackish brown. 
40 
