
4, 
Le 
2. 
ay 
BLACK DUCK (Continued) 
Middle Coverts: 
(a) First row anterior to greater coverts appear small, 
narrow and trapezoidal, and/or some coverts in 
either of 2 rows anterior to this (particularly 
over tertials) appear small and narrow or of 
obviously different plumage ---------------------- 
Immature 
(b) First row anterior to greater coverts appear medium 
to large, rounded tips and no coverts of obviously 
different plumages ------------------------------- 
Sex Determination of Adults 
Wing length: (see Plate 2) 
(a) 282 mm. or longer ------------------------.~-------+ 
(b) 281 mm. or leSs§ --------nn nnn rem wenn nnn nen ee nn nena 
Wing length: (continued) 
(a) 278 mm. or less ---------------------------------- 
(b) 279-281 mm. ------------------------------~------- 
Speculum: 
(a) Three most distal secondaries lack purple color 
(faint iridescence may show when tilted) ------~-- 
(b) Not more than two of most distal secondaries 
lack purple color ------------------22-- ee een nnn 
Tertials: 
(a) At least one of two longest tertials edged 
ON tip «--------- nnn eee nen en ene ee nnn eee 
(b) No tertials edged at tips ~----------------------- 
Adult Male 
Adult Female 
Adult Female 
Adult Female 
