island. They do not migrate, but build on the small outlying islets.
This is supposed to be from fear of the foxes: and it is perhaps from
the same cause that these birds, though very tame by day, are shy and
wild in the dusk of the evening. They live entirely on vegetable
matter.
The rock-goose, so called from living exclusively on the sea-beach
(Anas antarctica), is common both here and on the west coast of
America, as far north as Chile. In the deep and retired channels of
Tierra del Fuego, the snow-white gander, invariably accompanied by his
darker consort, and standing close by each other on some distant rocky
point, is a common feature in the landscape.
In these islands a great loggerheaded duck or goose (Anas brachyptera),
which sometimes weighs twenty-two pounds, is very abundant. These
birds were in former days called, from their extraordinary manner of
paddling and splashing upon the water, race-horses; but now they are
named, much more appropriately, steamers. Their wings are too small
and weak to allow of flight, but by their aid, partly swimming and
partly flapping the surface of the water, they move very quickly. The
manner is something like that by which the common house-duck escapes
when pursued by a dog; but I am nearly sure that the steamer moves its
wings alternately, instead of both together, as in other birds. These
clumsy, loggerheaded ducks make such a noise and splashing, that the
effect is exceedingly curious.
Thus we find in South America three birds which use their wings for
other purposes besides flight; the penguins as fins, the steamer as
paddles, and the ostrich as sails: and the Apteryz of New Zealand, as
well as its gigantic extinct prototype the Deinornis, possess only
rudimentary representatives of wings. The steamer is able to dive only
to a very short distance. It feeds entirely on shell-fish from the
kelp and tidal rocks: hence the beak and head, for the purpose of
breaking them, are surprisingly heavy and strong: the head is so strong
that I have scarcely been able to fracture it with my geological
hammer; and all our sportsmen soon discovered how tenacious these birds
were of life. When in the evening pluming themselves in a flock, they
make the same odd mixture of sounds which bull-frogs do within the
tropics.
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