400 



Key to Plate No. 6 Plate No. 6 -*> 



WINTER AND AUTUMN PLUMAGES 



(A) COMMON MALLARD, adult female. 



(B) COMMON MALLARD, adult male in early stage of autumn plumage. 



(C) COMMON MALLARD, adult male in later stage of autumn plumage. 



(D) COMMON MALLARD, adult male in advanced stage of autumn plu- 



mage. 



(E) COMMON MALLARD, adult male in full winter plumage. 



(F) COMMON MALLARD, adult wing, both sexes. 



Chief distinguishing features of COMMON MALLARD: MALE, (a) Hind 

 toe without lobe, (b) green head and neck, with white collar, (c) speculum, 

 bordered in front and behind with white bars, (d) middle upper tai 1 - 

 coverts curled upwards. FEMALE, (a) Hind toe without lobe, (b) specu- 

 lum, bordered in front and behind with white bars, (c) bill, orange and 

 dusky, (d) tail, very pale or whitish. 



Downy Young, Plate No. 33. 

 Hybrids, Plate No. 36. 

 Text : page 149. 



" ECLIPSE" PLUMAGE 



This plate illustrates the phenomenon of the "eclipse" moult which takes 

 place in the males of most of the ducks during the summer. 



EXPLANATION. Fig. (E) shows the Mallard drake in full winter plu- 

 mage. Fig. (A) shows the female Mallard. 



As soon as incubation is well started in the early summer, the males of most 

 of the ducks desert the females, gather in flocks by themselves and proceed to 

 moult their striking winter plumage shown in Fig. (E). 



The males then take on a plumage which in most cases is similar to that of 

 the female, Fig (A). While in this dress the flight-feathers are shed simul- 

 taneously, possibly on the same day, and the birds lose the power of flight until 

 the flight-feathers are renewed. 



As soon as the flight-feathers are grown in again (usually in August) the 

 birds commence a second moult out of the female-like eclipse plumage, Fig. (A), 

 back into the full winter dress, Fig. (E), and during the autumn are found in 

 various stages of this moult as shown by Figs (B), (C) and (D). 



For details of moults and plumages see page 22. 



