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has been introduced by various acclimatization societies, and by the Government, 
into many parts of New Zealand and according to Buller (1905) it is gradually sup- 
planting the native ducks and hybridizing with them. 
On some of the Pacific Islands this duck is undoubtedly becoming very scarce, 
due to the introduction of various predatory mammals, chiefly the mongoose. 
On Viti Levu (Fiji group), where it formerly existed in enormous numbers, it fell an 
easy prey to the latter animal and it is now extremely rare, though there are still 
considerable numbers on Ovalau (P. H. Bahr, 1912). Mr. Norman Hall writes me 
that in Tahiti ducks are now very scarce, while in the Kermadec group, according 
to Cheeseman (1891), this duck has been scarce since the eruption of 1872. 
Enemies. In Australia the introduced fox, domestic cat, and ferret are the most 
persistent enemies of the water-fowl. Mr. Charles M. Hoy, collecting for the 
United States National Museum, writes me that the ferret is the least widely dis- 
tributed, and that he himself found it only on the north coast of New South Wales. 
The fox has increased very rapidly, and is now found all over Queensland, New 
South Wales, Victoria and South Australia, and has begun to invade West Australia. 
He thinks the fox is doing by far the greatest damage to ducks, besides creating 
great havoc among the swans. It seems very likely that all ducks that nest on the 
ground will eventually be exterminated unless they can find islands in swamps and 
lakes suflScient for their needs. The cat is now distributed all over, including the 
desert interior, and is the next worst enemy of ducks. While it prefers smaller birds 
Mr. Hoy considers it an important enemy. The ferret he has never seen attack ducks 
but he thinks it probably destroys young in the nest. 
The Black-cheeked Falcon (Falco melanogenys) has been seen to kill twelve ducks 
of this and other species in one hour, without making any attempt to pick up the kills 
(F. C. Morse, 1919). 
Mr. Charles T.Barnard writes to me from Duaranga {via Rockhampton), Australia, 
that some of the hawks seem to be the principal natural enemies of the ducks, the 
Radiated Goshawk {Astur fasciatus) in particular and to a lesser degree the Little 
Eagle {Hieraaetus pennatus) both of which strike ducks while on the wing. The 
Whistling Eagle {Haliastur sphenurus) attempts to catch young ducks, although he 
has never actually seen it succeed. Mr. Barnard also names the water-rat {Ilydromys 
chrysogaster) as a possible enemy, for it quickly destroys all wounded ducks. 
Food Value. The flesh is excellent, especially at the beginning of the shooting 
season, when the birds are fat. Those from the interior lakes are quite naturally of a 
better flavor than those taken on the coasts. Buller (1888) regards it as perhaps the 
most valuable of the indigenous birds of New Zealand. The birds reach about 2.5 
pounds (1.13 kilograms) in weight, a little less than Mallard, and invariably 
