260 CASARCA TADORNOIDES 



Remarks on Moult: In this species also there is good evidence of a double moult, which probably 

 occurs in all species of this genus, but the eclipse or summer dress is so little different from the breed- 

 ing dress that it has largely escaped notice. Fortunately Mr. Blaauw (Ibis, ser. 6, vol. 6, p. 317, 1894) 

 has made very full observations on captive specimens, which I extract at length. 



"In May the first moult takes place of all feathers, primaries and tail-feathers included. The rich 

 shining chestnut feathers of the breast are then replaced by dull yellowish-brown feathers, and the 

 white neck-collar is replaced by another collar, also white, but not so clearly defined, and not nearly 

 so pure in colour. This is the winter dress. At the end of August generally, the second moult (of the 

 small feathers only) begins and produces the breeding dress. The dull yellowish breast-feathers are 

 then shed and replaced by the bright chestnut-coloured ones, whilst the shiny white neck-collar is also 

 regained. These bright feathers also seem to have a different structure from those of the winter dress, 

 being much more silky and hairy in appearance. 



"... ducks of the genus Tadorna are generally supposed to moult only once a year . . . [but] I have 

 had my pair now for three years, and the double moult . . . has occurred quite regularly each year." 



DISTRIBUTION 



The Mountain Duck belongs to the southern half of Australia and to Tasmania. The northernmost 

 record seems to be that for the Fitzroy River, in northwestern Australia, where Keartland (North, 

 1898) saw a few. In the southern parts of West Australia the species is tolerably plentiful and is gen- 

 West erally distributed throughout the western, central and southwestern divisions (Ogilvie- 

 Australia Grant, 1910), having been recorded for Lake Way (North, 1898), Lake Violet and for 

 East Murchison (Whitlock, Emu, vol. 9, p. 190, 1910), Wongan Hills (Milligan, Emu, vol. 4, p. 11, 

 1904), Moora (Orton and Sandland, 1913), Cumminin Station (Crossman, Emu, vol. 9, p. 86, 1909), 

 and Cape Mentelle, on the southwest coast (Milligan, Emu, vol. 2, p. 76, 1902). Mathews (1914- 

 15) quotes Carter who states that he saw these birds in thousands and that he found them breeding 

 on Lake Muir, and in a recent article Carter and Mathews (1920) make similar statements, recording 

 the species also for a lake one hundred and forty miles east of Perth, where large flocks were seen. 

 (See also W. B. Alexander, Emu, vol. 20, p. 160, 1921.) 



In South Australia the Mountain Duck was seen on the Palmer River (North, 1898), but its chief 

 center of distribution is southeastern South Australia and western Victoria. It has been found 

 South at Kellidie Bay, Eyre Peninsula (R. Hall, 1910), but most records are for the region east 



Australia f Spencer's Gulf and along the lower Murray River. Eylmann (1911) says it occurs 

 in large flocks in this region. White (1914) has recorded it for the Dalhousie region. It is said to be 

 very rare at Balah, but fairly common in Burra (Sandland, fide Mathews, 1914-15), while it breeds 

 about Gawler (Gould, 1865). About the mouth of the Murray River, on Lakes Albert and Alexan- 

 dria, it is a fairly common breeder Q>le\\oT,fide Mathews, 1914-15). White (fide Mathews, 1914-15) 

 found it in enormous numbers on Lake Albert. 



The species is perhaps commonest in western Victoria. The correspondents of North (1913) and 

 v . . . Mathews (1914-15) give ample proof of this, and it would be useless to quote all avail- 



able records for this region. Suffice it to say that it has been found breeding at Hamilton 

 (Macgillivray.^rfe North, 1913), Ararat (Hill, Emu, vol. 7, p. 23, 1907), Lake Boga (A. C. Stone, 1912), 

 Caramut (Mann, fide North, 1913), Winchelsea (Austin, fide North, 1913), and South Gippsland (ibid.). 

 rj, . In Tasmania the Mountain Duck appears to be generally distributed but not common. 



It has been found breeding on the Macquarie River (Brent, fide North, 1913). 



So far as known this duck has never been taken in the northern parts of New South Wales. Ram- 

 say (1876a) says they were for sale in the Sydney market in his day. These specimens probably came 

 from Lakes George and Bathurst, the species being confined to the southeast part of this State (North, 

 1913). 



