British Diving Ducks 
brown with sandy-brown edges to the feathers ; the belly is sometimes white, but usually 
shows numerous brown upper parts to the feathers, which give it a spotted appearance. 
The tail and primaries are not nearly so rich or dark as in adults, and as the season 
advances these parts become pale and worn. In March the greater part of the plumage 
is renewed, and it is scarcely possible to tell some young birds from old, whereas others 
retain much of the juvenile plumage. The rump, however, is never so dark as in females 
of over two years. Immature females seldom breed in the first spring, but I have known 
instances of them doing so. 
A dult Female resembles the male closely, but head, neck, upper breast, and flanks are 
not nearly of so rich a chestnut brown. The breast is seldom pure white like the male, and 
the brown flank feathers extend farther into the breast. In full winter the brown of the 
upper breast is edged with sandy-white, but this disappears by the end of March, and 
the whole of the chest is a clearly defined band of red brown. The grey vermiculations 
on the upper scapulars are not nearly so clear as in the male, but those on the thighs 
and on the brown of the lower belly are similar to the male. The white vent is also similar 
to the male. As is the case in all the adult female diving ducks, the females wear off 
the white end of the belly feathers and also have a number of new brown feathers on 
the breast in the nesting time, so that the bird bears a very dark appearance at this season, 
but not so dark as the Tufted Duck. 
The legs and feet are bluish-black. At all seasons the female can be identified from 
the male by its red-brown eye, but with advancing age the irides become whiter and 
eventually quite white. The white spot on the chin is similar to the male, and the vent 
is brown and under tail-coverts white. Length 15^ inches. 
I find that Naumann's views with regard to the moults and breeding periods 
coincide with my observations of this species, both in a wild state and in confine- 
ment. He says : — 
"At the beginning of July the males begin to moult, and have got through it in the following month, 
and now have, too, new wing and tail feathers and their less showy summer plumage in place of the 
glory dress (the summer one). This is at its best in September. I have myself killed one such male 
on the 27th Sept. which had this summer plumage at its freshest stage, both with regard to the feathers 
and their colours. But by the middle of October the second moulting has begun, which, within four to 
six weeks, gives them a new glory dress, which does not, however, extend beyond pinion and tail 
feathers. The young males, too, now (somewhat later than the adult males) lose their feathers in order 
to assume their first mating, or glory dress, but with these the process is a much slower one, so that some 
have not got it completely when they take their places at the breeding haunts in the spring. The 
females moult only once every year, as a rule, early in August, when the young are reared, and the 
young females keep their young-bird plumage until the following spring, and then moult for the first time 
in the second summer of their existence at the same time as the adult females do. 
They breed, accordingly, as a rule while still in the young-bird plumage ; it is thus only young 
females belonging to a belated brood which are often unable to fly by September (though others can 
normally do this in August) which may possibly remain unmated in the next spring, or perhaps arrive at 
that stage later than others, for such birds are often seen wandering about alone in unfrequented places in 
May, and a few years ago I killed one such female on May 3rd at the pond here, but it was a remarkably 
small specimen and its ovary was very little developed, and the dark brown pupils of the eyes were only 
just beginning to colour grey on the outer rim." 
^ According to my experience, a few adult males commence the winter moult long before this. I have seen some in full 
winter dress on October loth. 
