The COMMON SISKIN (_Spinus viridis_) is about five inches long, and nine
across the span of the wings. In the male the top of the head is black,
the back yellowish green, streaked with blackish grey; the wings, which
are blackish, have two yellow stripes. The under part of the body is
bright yellow upon the breast, and white upon the belly; the throat is
black. The female bird is greyish green upon the upper parts of the body,
streaked with a darker shade; the under parts are white or yellowish
white, and marked with longish black spots. The young are yellower and
more variegated in their markings than the female.
The Siskin is particularly numerous in mountain regions, chiefly
inhabiting the interior of Norway, Sweden, and Russia. It is unknown
in Northern Asia, but is occasionally met with in the north-eastern
portions of that continent; Radde mentions flocks of these birds seen by
him in the Bareja Mountains, and near the banks of the Amur. The Siskins
are birds of passage, and, except in the breeding season, spend their
time in wandering over the country, going south for the winter in great
numbers, should the season be unusually cold or food deficient. In the
summer months they frequent the pine forests of mountainous districts,
living upon the seeds that are found there in abundance. In these places
they also breed. During their migratory excursions they often appear in
winter by thousands close to the villages, in districts where, in less
inclement seasons, not one is to be seen. In these wanderings, barren
tracts of country are carefully avoided, and they prefer perching upon
the topmost branches of forest trees. "The Siskin," says Naumann "is
always lively, adroit, and bold, and very attentive to the care of its
plumage; it is brisk in its movements, and a most capital climber."
In this respect it much resembles the Titmouse, frequently hanging
backwards from the boughs, which it ascends quickly, even should they
be quite perpendicular--in short, among the branches it is never quiet,
except when asleep or while taking its food. It can also hop nimbly
upon the ground, always, however, appearing to avoid descending from
its perch, if not obliged to do so. Its flight is undulating, rapid,
and light; it can pass with ease over large tracts of country, and rise
to a considerable height in the air. Its song is a very simple, but
not unpleasing, twitter. In all other respects this species strongly
resembles the Birch-tree Siskin; in disposition it is social, peaceful,
and thoughtless--indeed, we do not know any bird that shows so little
regret at the loss of its freedom, or is more suitable for domestication.
Moreover, it is very docile, and learns many little tricks, is not at all
dainty concerning the quality of its food, and becomes so tame that it
may be allowed to leave its cage at pleasure, and will obey its master's
call. Hoffmann relates of several of these birds that were kept in his
aviary, that they could be allowed to fly about, and would readily take
their food from his hand. On one occasion, as he tells us, a flock of
wild Siskins passed over the garden while one of his captive birds sat
perched upon his hand. The tame bird had no sooner heard the call-notes
of its brethren than it responded to the invitation, and flew at once to
join the party upon a neighbouring tree, receiving a very warm reception
from the little strangers, both individually and collectively. Of course
he gave his pet Siskin up as lost, but made an effort to allure it back
by its call-note and some favourite food. These efforts were successful,
and the truant was again soon perched upon his hand, although it was
followed by one of the wild birds to within six feet of the place where
he stood.
Seeds of many kinds--but principally those of trees--young buds, tender
leaves, and, during the breeding season, caterpillars and various
insects, constitute the ordinary food of these birds, the nestlings
being fed exclusively upon the latter diet--caterpillars, aphides, &c.
It is for this reason that the parent birds often frequent gardens
and orchards, accompanied by their young, such localities affording a
larger supply of insects than is to be met with in the forests. When in
captivity a little seed and a few green weeds will satisfy all their
requirements.
[Illustration: GOLDFINCHES AND NEST.]
The Siskin seeks its mate in April, obtaining her favour by very much the
same efforts as those practised by the Cross-bills, the male bird, at
such times, looking much larger than it really is, spreading its wings,
and wheeling around her at a considerable height in the air, and at the
same time singing vigorously. During this courtship the female remains
quite quiet, only from time to time caressing her companion with her
beak, or making short excursions in his company. Occasionally many of
these little couples will join company, and live in the utmost peace and
unity. The building of the nests begins shortly after the pairing of the
birds, and all must admire the cunning with which the female selects a
suitable spot, and fully appreciate the popular idea that a Siskin's nest
is invisible. The locality fixed upon is generally the extreme end of a
thick, lofty branch, the foliage of which entirely conceals the little
domicile. Fir and pine-trees are frequently selected for nidification,
and so perfectly does the exterior of the nest resemble the branch upon
which it is placed, that it is only recognisable when seen from above,
in which position it is betrayed by its rounded interior--indeed, so
completely is it hidden from observation, that a servant sent by us into
a tree to discover the nest, was about to descend without it, even though
it lay but two feet distant from him; and had we not recommended him to
strip the branch by removing one twig after another, he probably would
have sought for it in vain. This plan, however, succeeded, and the prize
was secured. The skill with which these little creatures conceal their
young has prevented any one from having seen the nest in progress of
erection, and will account for the old-fashioned legend that the Siskin
builds with invisible stones--for so very great is the difficulty of
distinguishing these structures from the surrounding branches, that few
naturalists have succeeded in finding them. The progress of the work is
extremely rapid. The two birds that we saw laboured alternately, each
waiting while the other supplied fresh materials, and then flew together
in search of what more was required, bringing back beakfuls of dry
twigs, wool, or moss, which they tore from the bark of the trees. It was
curious to see the little creatures prepare the wool, with which the nest
is lined, by holding it with the foot while pulling it out with their
beak to render it soft and elastic. In some other instances that have
come under our notice, the female alone constructed the nest, the male
keeping near her during the whole time. When busy in the preparation of
their dwelling, these little birds testify no uneasiness if watched or
approached, though they have been known to leave a partially constructed
nest, and commence another. The vicinity of water is always preferred
in the choice of a tree on which to build. The nests vary considerably
in their appearance. They are formed of twigs and moss, bound strongly
together with cobwebs, and lined with feathers, hair, and various kinds
of delicate fibres. The walls are very thick, and the central cavity
deep. The breeding season usually commences about the beginning of June,
but young fledged birds have been seen as early as May. The eggs, which
resemble those of the Brown Linnet, differ remarkably from each other in
size, shape, and colour, but are, for the most part, of a whitish-blue or
blueish-green, marked with a variety of spots and veins. The female alone
sits upon the eggs, remaining on the nest from the time that the first is
laid. The Siskin has been known to breed in captivity.