Not the least of the many benefits which birds confer upon man is the
unceasing warfare which the majority of them wage upon insects. Insects
may be said to dominate the earth; they fill every nook and cranny of it,
preying upon all other living things which they outnumber. If this is the
state of affairs when hundreds of millions of insects are devoured daily
by their arch-foes, the fowls of the air, what would it be were there no
birds? The earth would certainly not be inhabited by men.
Most insectivorous birds specialise, that is to say, lay themselves out
to catch a particular class of insect. Swifts, swallows, and flycatchers
have developed phenomenal mastery over the air, so prey upon flying
insects. Mynas, hoopoes, “blue jays,” magpie-robins, and others feed upon
the hexapod hosts that crawl on the ground. Not a few birds confine their
attention to the creeping things that inhabit the bark of trees. Such are
the wryneck, the tree-creeper, and the woodpecker. Of these the
woodpecker is chief. A mighty insect hunter is he, one who tracks down
his quarry and drags him out of his lair. How must the insects which lie
hidden away in the crevices of the bark tremble as they hear this
feathered Nimrod battering at the walls of their citadel!
No bird is better adapted than the woodpecker to the work which nature
has given him. He is a perfect hunting machine, constructed for work in
trees. Note the ease with which he moves over the upright trunk. His
sharp claws can obtain a foothold on almost any surface. I have seen a
golden-backed woodpecker hunting insects on a smooth well-wheel!
His tail, which is short and composed of very stiff feathers, acts almost
like a third leg. The bristle-like feathers stick in the crevices of the
bark and enable the bird to maintain his position while he hammers away
with might and main. His head is his hammer and his beak his chisel. The
chisel is fixed rigidly in the hammer so that none of the force of the
blow is lost. It is exhilarating to watch a woodpecker at work. He stands
with his legs wide apart, the tip of his tail pressed firmly against the
bark, and puts all he knows into each stroke, drawing his head back as
far as it will go and then letting drive. The manner in which his strokes
follow one another puts me in mind of the clever way in which workmen
drive an iron bar into a macadamised road by raining upon it blows with
sledge-hammers. Almost before the hammer of the first striker is off the
head of the bar the second has struck it, this is immediately followed by
the hammer of the third, then, without a pause, the first hammerer gets
his second blow home, and so they continue until a halt is called. As a
small boy I would stand for hours watching the operation. I am ashamed to
do so now, so have to content myself with observing woodpeckers at work!
There are few things more fascinating to watch than an operation in which
skill and brute force are deftly combined.
Even more useful than the beak as a weapon is the woodpecker’s tongue.
This is such an important organ that its owner is known in some parts of
England as the tongue bird. It is so long that there is a special
apparatus at the back of the bird’s head for stowing it away. Its surface
is studded with backwardly pointing bristles and the whole covered with
sticky saliva. When the woodpecker espies a crack in the bark it inserts
into it the long ribbon-like tongue. To this the luckless insects stick
and are ruthlessly dragged out to their doom.
The commonest woodpecker in India is the beautiful golden-backed species
(_Brachypternus aurantius_). The head and crest of the cock are bright
crimson, the upper back is a beautiful golden yellow, hence the popular
name of the bird. The lower back and tail are black; the wing feathers
are black and golden yellow, spotted with white, and the sides of the
head show a white background on which there is a network of black lines
and streaks.
The hen differs from the cock in having the top of the head black with
small white triangular spots.
The golden-backed woodpecker is one of our noisiest birds. It constantly
utters its loud screaming call, which is similar to that of the
white-breasted kingfisher. Its flight, like that of most, if not all
woodpeckers, is laborious and noisy, the whir of its wings being audible
at a considerable distance. The bird gives one or two vigorous flaps of
its wings and thus moves in an upward direction, then it sails and sinks;
a few more flaps again send it upwards, and so it continues until it
reaches the tree trunk for which it is bound.
I do not think that the woodpecker ever takes a sustained flight. It is
seen at its best when on the stem of a tree, over which it moves with
wonderful ease in a series of silent jerks, like a mechanical toy. It
always keeps its head pointing heavenwards and hops or jerks itself
upwards, downwards, or sideways, with equal ease, just as though it went
by clockwork. It sometimes ventures on the ground, from which it digs out
insects. On the earth it progresses in the same jerky manner.
I have never seen a woodpecker sitting like an ordinary bird on a perch.
It is often seen on branches, but always lengthwise, never sitting across
the branch. It can move along the under surface of a horizontal bough as
easily as a fly walks on the ceiling.
I sometimes wonder how woodpeckers roost. Do they sleep hanging on to the
trunk of some tree, do they sit lengthwise on a branch as a nightjar
does, or do they repair to some hole? I should be inclined to favour the
last of these alternatives but for the fact that woodpeckers seem to
excavate a new nest every year. This would not be necessary if each bird
had a hole in which it slept at night.
Sometimes the bird digs out the whole of its nest, but this is not usual.
The woodpecker belongs to the “labouring classes,” and, true to the
traditions of its caste, it is averse to work, so generally utilises a
ready-made cavity. It taps away at tree after tree until it comes upon a
place in a trunk that sounds hollow; it then proceeds to excavate a neat,
round passage leading to this hollow. In this ready-made cavity it
deposits its white eggs, not troubling to add any lining to the nesting
chamber.
Woodpeckers in England suffer much at the hands of rascally starlings.
These latter nest in holes, but not of their own making. If they cannot
find any ready-made hollow they listen for the hammering of a woodpecker.
They wait until he has completed the nest, and then take possession while
his back is turned. When the rightful owner returns the starling looks
out of the entrance with finely simulated indignation and asks the
woodpecker what he means by intruding. In vain does the latter
expostulate. _J’y suis, j’y reste_ is the attitude of the starling. The
result is that our feathered carpenter, not being over-valorous, retires
and proceeds to hew out another nest. Woodpeckers in India do not suffer
such treatment, for starlings do not breed in this country. Their
cousins, the mynas, are not so impudent. The only Indian birds which nest
in holes, and have sufficient impudence to eject a woodpecker, are the
green parrots; but these breed in January, so that their family cares for
the year are over long before the woodpecker begins nest building.