VOICES OF THE NIGHT
The majority of
nocturnal animals, more particularly those bent on spoliation, are
strangely silent. True, frogs croak in the marshes, bats shrill
overhead at so high a pitch that some folks cannot hear them, and
owls hoot from their ruins in a fashion that some vote melodious and
romantic, while others associate the sound rather with midnight crime
and dislike it accordingly. The badger, on the other hand, with the
otter and fox—all of them sad thieves from our point of view—have
learnt, whatever their primeval habits, to go about their marauding
in stealthy silence; and it is only in less settled regions that one
hears the jackals barking, the hyænas howling, and the browsing deer
whistling through the night watches.
There are,
however, two of our native birds, or rather summer visitors, since
they leave us in autumn, closely associated with these warm June
nights, the stillness of which they break in very different fashion,
and these are the nightingale and nightjar. Each is of considerable
interest in its own way. It is not to be denied that the churring
note of the nightjar is, to ordinary ears, the reverse of attractive,
and the bird is not much more pleasing to the eye than to the ear;
while the nightingale, on the contrary, produces such sweet sounds as
made Izaak Walton marvel what music God could provide for His saints
in heaven when He gave such as this to sinners on earth. The
suggestion was not wholly his own, since the father of angling
borrowed it from a French writer; but he vastly improved on the
original, and the passage will long live in the hearts of thousands
who care not a jot for his instructions in respect of worms. At the
same time, the nightjar, though the less attractive bird of the two,
is fully as interesting as its comrade of the summer darkness, and
there should be no difficulty in indicating the little that they have
in common, as well as much wherein they differ, in both habits and
appearance.
Both, then, are
birds of sober attire. Indeed of the two, the nightjar, with its soft
and delicately pencilled plumage and the conspicuous white spots, is
perhaps the handsomer, though, as it is seen only in the gloaming,
its quiet beauty is but little appreciated. The unobtrusive dress of
the nightingale, on the other hand, is familiar in districts in which
the bird abounds, and is commonly quoted, by contrast with its
unrivalled voice, as the converse of the gaudy colouring of raucous
macaws and parrakeets. As has been said, both these birds are summer
migrants, the nightingale arriving on our shores about the middle of
April, the nightjar perhaps a fortnight later. Thenceforth, however,
their programmes are wholly divergent, for, whereas the nightjars
proceed to scatter over the length and breadth of Britain,
penetrating even to Ireland in the west and as far north as the
Hebrides, the nightingale stops far short of these extremes and
leaves whole counties of England, as well as probably the whole of
Scotland, and certainly the whole of Ireland, out of its
calculations. It is however well known that its range is slowly but
surely extending towards the west.
This curiously
restricted distribution of the nightingale, indeed, within the limits
of its summer home is among the most remarkable of the many problems
confronting the student of distribution, and successive ingenious but
unconvincing attempts to explain its seeming eccentricity, or at any
rate caprice, in the choice of its nesting range only make the
confusion worse. Briefly, in spite of a number of doubtful and even
suspicious reports of the bird's occurrence outside of these
boundaries, it is generally agreed by the soundest observers that its
travels do not extend much north of the city of York, or much west of
a line drawn through Exeter and Birmingham. By way of complicating
the argument, we know, on good authority, that the nightingale's
range is equally peculiar elsewhere; and that, whereas it likewise
shuns the departments in the extreme west of France, it occurs all
over the Peninsula, a region extending considerably farther into the
sunset than either Brittany or Cornwall, in both of which it is
unknown. No satisfactory explanation of the little visitor's
objection to Wild Wales or Cornwall has been found, and it may at
once be stated that its capricious distribution cannot be accounted
for by any known facts of soil, climate, or vegetation, since the
surroundings which it finds suitable in Kent and Sussex are equally
to be found down in the West Country, but fail to attract their share
of nightingales.
The song of the
nightingale, in praise of which volumes have been written, is perhaps
more beautiful than that of any other bird, though I have heard
wonderful efforts from the mocking-bird in the United States and from
the bulbuls along the banks of the Jordan. The latter are sometimes,
more especially in poetry, regarded as identical with the
nightingale; and, indeed, some ornithologists hold the two to be
closely related. What a gap there is between the sobbing cadences of
the nightingale and the rasping note of the nightjar, which, with
specific reference to a Colonial cousin of that bird Tasmanians
ingeniously render as "more pork"! It seems almost
ludicrous to include under the head of birdsong not only the music of
the nightingale, but also the croak of the raven and the booming note
of the ostrich. Yet these also are the love-songs of their kind, and
the hen ostrich doubtless finds more music in the thunderous note of
her lord than in the faint melody of such song-birds as her native
Africa provides. The nightingale sings to his mate while she is
sitting on her olive-green eggs perching on a low branch of the tree,
at foot of which the slender nest is hidden in the undergrowth. So
much is known to every schoolboy who is too often guided by the sound
on his errand of plunder; and why the song of this particular warbler
should have been described by so many writers as one of sadness,
seeing that it is associated with the most joyous days in the bird's
year, passes comprehension. So obviously is its object to hearten the
female in her long and patient vigil that as soon as the young are
hatched the male's voice breaks like that of other choristers to a
guttural croak. It is said, indeed—though so cruel an experiment
would not appeal to many—that if the nest be destroyed just as the
young are hatched the bird recovers all his sweetness of voice and
sings anew while another home is built.
Although poetic
licence has ascribed the song to the female, it is the male
nightingale only that sings, and for the purpose aforementioned. The
note of the nightjar, on the other hand, is equally uttered by both
sexes, and both also have the curious habit of repeatedly clapping
the wings for several minutes together. They moreover share the
business of incubation, taking day and night duty on the eggs, which,
two in number, are laid on the bare ground without any pretence of a
nest, and generally on open commons in the neighbourhood of patches
of fern-brake. Like the owls, these birds sleep during the day and
are active only when the sun goes down. It is this habit of seeking
their insect food only in the gloaming which makes nightjars among
the most difficult of birds to study from life, and all accounts of
their feeding habits must therefore be received with caution,
particularly that which compares the bristles on the mouth with
baleen in whales, serving as a sort of strainer for the capture of
minute flying prey. This is an interesting suggestion, and may even
be sober fact; but its adoption would necessitate the bird flying
open-mouthed among the oaks and other trees beneath which it finds
the yellow underwings and cockchafers on which it feeds, and I have
more than once watched it hunting its victims with the beak closed. I
noticed this particularly when camping in the backwoods of Eastern
Canada where the bird goes by the name of nighthawk.
In all
probability its food consists exclusively of insects, though
exceptional cases have been noted in which the young birds had
evidently been fed on seeds. The popular error which charges it with
stealing the milk of ewes and goats, from which it derives the
undeserved name of "goat-sucker," with its equivalent in
several Continental languages, is another result of the imperfect
light in which it is commonly observed. Needless to say, there is no
truth whatever in the accusation, for the nightjar would find no more
pleasure in drinking milk than we should in eating moths.
Here, then, are
two night-voices of very different calibre. These are not our only
birds that break the silence on moonlight nights in June. The common
thrush often sings far into the night, and the sedge-warbler is a
persistent caroller that has often been mistaken for the nightingale.
The difference in this respect between the two subjects of these
remarks is that the nightjar is invariably silent all through the
day, whereas the nightingale sings joyously at all hours. It is only
because his splendid music is more marked in the comparative silence
of the night, with little or no competition, that his daylight
concert is often overlooked.
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