50 The Natural History of British Ducks 
contrast that is somewhat surprising. For instance, in the gradual change of 
the young male Wigeon, which takes place between September and February, 
there is only a slight grey suffusion and pattern change over the brown feathers 
of the back ; the sides and often the back of the neck obtain certain bars, but 
all the rest of the plumage, except the wings and tail, seems to undergo 
the usual moult, which gradually takes place through these months ; the new 
feathers themselves coming in, not with any half-measure compromise with 
first plumage feathers, but in the full completion of the winter dress. The 
great flush of new feathers, including a new tail, seems to take place in 
March or April, just when the birds are about to leave us, and it is then 
that the most remarkable transition is seen. 
The young male may now be said to have changed its complete plumage, 
except the wing, to that of the adult; and as the wing never moults at this 
season of the year, in very well-advanced birds, the greater part of the 
shoulder above the secondaries now changes colour from brown-grey to white. 
Thus the bird appears in full plumage, although it has not yet undergone one 
complete moult. 
As I previously stated, the majority of the young males do not change 
the colour of the upper part of the wing at this period ; but court the 
females, pair with them, and retire to the breeding grounds whilst still 
retaining outward appanages of youth. 
Both young and old males begin to assume the eclipse plumage about 
the same time, i.e as early as the beginning of June, or as late as the 
beginning of July;^ but this, of course, varies with geographical distribution; 
and though practically the full brown dress at this time is assumed by the 
young male with dark wing, he still retains the dark wing till August or 
September, when he completely moults his wings, and becomes exactly the 
same as the fully adult bird. 
In the case of exceptionally backward young birds the greater part of the 
1 The new richly coloured red-brown flank feathers of young males in eclipse are sometimes ribbed with grey when 
they first come in, apparently in sympathy with their late plumage ; but these immature markings soon pass away. 
