1 8 The Natural History of British Ducks 
Change of Plumage of the Adult Mallard Drake from the Spring 
Dress into the Eclipse, and Eclipse into the Winter Dress 
The intricate change of plumage of the adult drake from the spring 
dress into the eclipse, and from that again into the winter dress, though one 
of the most interesting features in all duck life, has as yet remained 
untouched by the naturalist. The time that is required to study the subject 
thoroughly, the necessity of keeping alive a large number of birds, and the 
indispensable labour of collecting a very large series of their skins, have 
probably deterred others less fortunate than myself from attempting a solution 
of the question as to how these changes take place. For several years I have 
made this a special study, the result of which I shall now endeavour to lay 
before my readers. 
During the months of May, June, or July, all the surface-feeding drakes 
undergo a remarkable change in both colour and feather to a plumage which 
more or less resembles that of the female, though there are really many 
points of difference. It is no more correct to say that the drake assumes 
the plumage of the duck than that he moults directly into it. For the 
assumption of the new dress in June or July is not entirely due either to a 
mere change of colour without moult or to a renewal of feather, but is at first 
a combination of both. The general results of my observations go to show 
that between June 15 and October 10 (the period of the eclipse plumage) two- 
thirds of the Mallard's feathers (namely, those of the head, neck, breast, and 
parts of the back and scapulars) undergo a double moult, that is to say, the 
feathers are actually shed twice; whilst one-third of them (namely, the long 
scapulars, wings, tail and vent feathers) are renewed only once ; and during all 
this time, both in the shedding of the old feathers and the assumption of the 
new, there is in progress a constant sympathetic change of colour. 
The strange loss of beauty which, for a time, the drake undergoes is an 
extraordinary provision of nature. Why should he be shorn of his trappings 
and lose his attractions when so many other families of birds moult directly 
