It is matter of curious inquiry to trace out how those species of
soft-billed birds that continue with us the winter through subsist during
the dead months. The imbecility of birds seems not to be the only reason
why they shun the rigour of our winters; for the robust wryneck (so much
resembling the hardy race of woodpeckers) migrates, while the feeble
little golden-crowned wren, that shadow of a bird, braves our severest
frosts without availing himself of houses or villages, to which most of
our winter birds crowd in distressful seasons, while this keeps aloof in
fields and woods; but perhaps this may be the reason why they may often
perish, and why they are almost as rare as any bird we know.
I have no reason to doubt but that the soft-billed birds, which winter
with us, subsist chiefly on insects in their aurelia state. All the
species of wagtails in severe weather haunt shallow streams near their
spring-heads, where they never freeze, and, by wading, pick out the
aurelias of the genus of _Phryganeae_, etc.
Hedge-sparrows frequent sinks and gutters in hard weather, where they
pick up crumbs and other sweepings, and in mild weather they procure
worms, which are stirring every month in the year, as any one may see
that will only be at the trouble of taking a candle to a grass-plot on
any mild winter's night. Redbreasts and wrens in the winter haunt
outhouses, stables, and barns, where they find spiders and flies that
have laid themselves up during the cold season. But the grand support of
the soft-billed birds in winter is that infinite profusion of aurelia of
the _Lepidoptera ordo_, which is fastened to the twigs of trees and their
trunks, to the pales and walls of gardens and buildings, and is found in
every cranny and cleft of rock or rubbish, and even in the ground itself.
Every species of titmouse winters with us; they have what I call a kind
of intermediate bill between the hard and the soft, between the Linnaean
genera of _Fringilla_ and _Motacilla_. One species alone spends its
whole time in the woods and fields, never retreating for succour in the
severest seasons to houses and neighbourhoods; and that is the delicate
long-tailed titmouse, which is almost as minute as the golden-crowned
wren; but the blue titmouse or nun (_Parus caeruleus_), the cole-mouse
(_Parus ater_), the great black-headed titmouse (_Fringillago_), and the
marsh titmouse (_Parus palustris_), all resort at times to buildings, and
in hard weather particularly. The great titmouse, driven by stress of
weather, much frequents houses; and, in deep snows, I have seen this
bird, while it hung with its back downwards (to my no small delight and
admiration), draw straws lengthwise from out the eaves of thatched
houses, in order to pull out the flies that were concealed between them,
and that in such numbers that they quite defaced the thatch, and gave it
a ragged appearance.
The blue titmouse, or nun, is a great frequenter of houses, and a general
devourer. Besides insects, it is very fond of flesh, for it frequently
picks bones on dunghills: it is a vast admirer of suet, and haunts
butchers' shops. When a boy, I have known twenty in a morning caught
with snap mouse-traps, baited with tallow or suet. It will also pick
holes in apples left on the ground, and be well entertained with the
seeds on the head of a sunflower. The blue, marsh, and great titmice
will, in very severe weather, carry away barley and oat-straws from the
sides of ricks.
How the wheatear and whinchat support themselves in winter cannot be so
easily ascertained, since they spend their time on wild heaths and
warrens; the former especially, where there are stone quarries: most
probably it is that their maintenance arises from the aureliae of the
_Lepidoptera ordo_, which furnish them with a plentiful table in the
wilderness.