(BLACK-NECKED SWAN.)
[Plate XVIII.]
[Illustration: CYGNUS NIGRICOLLIS.]
+Cygnus nigricollis+, _Burm. La-Plata Reise_, ii. p. 512 (Paraná);
_Scl. et Salv. Nomencl._ p. 129; _iid. P. Z. S._ 1876, p. 370;
_Durnford, Ibis_, 1877, p. 191 (Buenos Ayres), et 1878, p. 400
(Centr. Patagonia); _Gibson, Ibis_, 1880, p. 33 (Buenos Ayres);
_Barrows, Auk_, 1884, p. 273 (Entrerios).
_Description._--White; head and neck black; postocular streak
and chin white; lores naked; bill plumbeous; cere red; feet pale
carneous: whole length 48·0 inches, wing 17·5, tail 5·5. _Female_
similar.
_Hab._ Argentina, Chili, and Patagonia.
To my perhaps partial mind this species is preeminent for beauty among
the Swans, although it is considerably smaller than the bird of the
Old World, and does not, it must be admitted, comport itself so
majestically. In questions of this kind it is natural for every one to
be somewhat biassed in favour of the things of his own country; but it
will be readily admitted by all, I think, that the black-necked bird
is one of three species greatly surpassing all others of this genus in
beauty--the other two being, of course, the domesticated Swan of Europe
and the Australian Black Swan (perhaps the most graceful bird on the
globe).
This Swan is very abundant on the pampas of Buenos Ayres and in
Patagonia, and ranges south to the Magellan Straits and the Falklands.
As a rule they are seen in small flocks, but sometimes as many as two
or three hundred congregate together. They are heavy birds and rise
with difficulty, and fly rapidly and with great violence, like all
heavy-bodied short-winged species; but in no other very large bird with
which I am acquainted do the wings produce so loud a rushing sound. In
quiet places the beating of their wings can be heard distinctly when the
birds are no longer in sight, although, owing to their large size, the
eye can follow them very far. Gauchos sometimes capture them by suddenly
charging down the wind upon them, uttering loud shouts which greatly
terrify the birds, and when they attempt to rise with the wind they
only flap along the ground and are easily knocked over. A Gaucho of my
acquaintance one day caught three out of a flock of six in this way; but
a very strong wind favoured him, and the birds were at some distance
from the water, and allowed him to come near before making the sudden
charge. As a rule, they are seen on the water, and when on land they
keep very close to the margin.
According to Mr. Gibson, who has observed their breeding-habits, they
begin to nest in July--just after the winter solstice. The nest is
always placed among thick rushes growing in deep water, and the Swan
invariably swims to and from her nest. It is built up from the bottom
of the swamp, sometimes through four or five feet of water, and rises
a foot and a half above the surface. The top of the nest measures
about two feet across, with a slight hollow for the eggs, which are
cream-coloured and have a smooth glossy shell. The number varies from
three to five, and on one occasion six were found. Mr. Gibson has seen
the parent bird swimming from the nest with the young on her back.
Our figure of this species (Plate XVIII.) is taken from the specimen now
living in the Zoological Society's Gardens.