Courtship Flights
"A pair of falcons wheeling on the wing,
In clamourous agitation ..."--_Wordsworth._
The wing-play of black-game and grouse--The "musical ride" of
the snipe--The "roding" of the woodcock--The musical flights of
redshank and curlew--The "tumbling" of the lapwing--The raven's
somersaults--The courting flight of the wood pigeon--The mannikin's
"castanets"--Wings as lures--The strange pose of the sun-bittern--The
"wooing" of the chaffinch and the grasshopper-warbler--Darwin and
wing-displays--The wonderful wings of the argus-pheasant.
One of the most striking features of
bird-life is surely its restless activity. This is always apparent,
but it attains to a state of almost feverish excitement as the spring
advances, and the parental instincts re-awaken. As they gather
strength, so they manifest themselves, in outbursts of song--often of
exquisite beauty--strange antics, or wonderful evolutions in mid-air.
It is with these last that we are chiefly concerned here. As might
be supposed, they present a wide variety in the matter of their form
and duration. Black-game furnish an example of a very simple form of
courtship flight, but it is associated with curious antics on the
ground. And these, it is to be noted, are only to be witnessed soon
after sunrise. Two blackcocks will approach one another and stand as
if prepared to ward off a very vigorous onslaught; reminding one of two
barn-door cockerels. With lowered head and neck they face one another,
the beautiful lyrate tail spread fan-wise, and arched so that the
curled, outer, feathers touch the ground, while the wings are trailed
like those of the turkey-cock. Then one will at last rush forward,
and seizing his adversary by the scruff of the neck, will administer
a sound beating with his wings. The victor celebrates his triumph by
a loud, and most unmusical screech, which has been likened, by that
accomplished observer and sportsman-artist, Mr. J. G. Millais, to the
call of cats on the house-tops at mid-night. But presently a grey-hen
makes her appearance. Hostilities cease at once, on all sides; and
intense excitement prevails amongst the whole assembly--for a large
number of cocks will gather together at these sparring matches. Her
approach has been observed by a single bird, who, unintentionally,
gives the signal by suddenly drawing himself up to a rigid position of
attention, till he is sure she is really coming, then he throws himself
into the air and flutters up a few feet, uttering at the same time, a
peculiar hoarse note of exultation. Immediately all the others follow
suit; each seeming to strive to outdo his neighbour in a series of
absurd pirouettings. Here we have a "Love-flight," of exceedingly brief
duration, associated with terrestrial combats and frantic prancings.
[Illustration: _Woodcock carrying Young_]
The grouse pursues a different method. He strives to incite his mate
to amourous moods by chasing her about. But she is "coy," and will
tolerate this for hours at a time, apparently intent on nothing more
than seeking something interesting to eat, she seems to affect to
be quite unaware of the presence of her importunate mate; though
her behaviour is belied by the fact that she keeps up a continuous
"cheeping" note, heard only at this time of the year. Every now and
then he will vary his tactics by leaping up into the air and taking
an upward flight of from twenty to thirty feet, crowing vociferously.
On alighting he will commence his addresses again. Then, perhaps, she
herself will take to flight, darting off and twisting like a snipe,
evidently enjoying her tantalizing tactics. He follows in close
pursuit, in the hope, doubtless, of satisfying his desires, when she
shall come to rest. Here is a "courtship" flight of longer duration, in
which both sexes participate.
The "musical ride" of the snipe is of a much more imposing character:
and in this, again, both sexes take a part. During this performance,
which affords some thrilling moments to the bird-lover, the bird
ascends to a great height, and then plunges earthwards in a terrific
"nose-dive" accompanied by a weird bleating noise, comparable to the
bleat of a goat. For long years discussion waged furiously as to the
source of this sound. Some held that it was produced by the voice:
others by the tremulous motion of the wing-feathers: others, again,
contended that it was caused by the tail feathers. This was first
mooted by the Danish naturalist, Meeves, and he produced some very
striking and curious evidence to prove his view. He showed that the
outermost tail-feathers had peculiarly thickened shafts, which were
also bent in a very striking way. By removing these feathers, and
sticking them into a cork, he was enabled, by twirling the cork rapidly
round at the end of a string, to reproduce the "bleat" exactly. Many
years later Dr. Philip Bahr revived this experiment, for the purpose
of finally setting the matter at rest--for there were still many who
remained unconverted to the Meeves interpretation. Dr. Bahr left no
room for further doubt. He showed, too, that during the production
of this sound these tail-feathers were extended laterally, so as
to separate them from the rest of the tail, and so give the air
rushing past them during the earthward plunge, full play on these
sound-producing structures. He too, applied the test first instituted
by Meeves, and so clinched his arguments. One may hear this strange
music as early as February, and even, though rarely, as late as July.
But it is essentially a breeding-season, or rather a "Courtship"
performance sound, though it may be evoked by a sitting bird suddenly
surprised, when she will "bleat" as she leaves her eggs, possibly to
distract the intruder on her vigil.
The woodcock has a "love-flight" but of a quite different character,
known by sportsmen as "roding." It takes the form of short flights
up and down the "ride," or space selected for the nesting site.
But while the female is sitting the male will still continue these
flights, choosing the early morning and evenings. As he goes he utters
strange cries, which have been compared, by some, to the words "more
rain to-morrow" and by others to, "Cro-ho, cro-ho," varied by a note
sounding like, "whee-e-cap." These flights are varied by strange little
displays upon the ground, when he will strut about before his mate with
wings drooped and trailing on the ground, the tail spread, and the
feathers of the head and neck standing on end. This gives him a very
odd appearance, to human eyes, but it serves its purpose--which is to
arouse his mate to amourous moods.
Redshank, curlew, and dunlin--cousins of the snipe and woodcock--are
all accomplished performers in the art of wooing on the wing. The male
redshank, uttering flute-like notes, Mr. Farren tells us, soars up to a
moderate height, and remains, for a brief space, "hanging in the wind"
with the tips of his curved wings rapidly vibrating. He then descends,
pipit-like, earthwards, while the song, which has been uttered slowly,
now quickens, reaching its climax as the bird, raising its wings above
its back for an instant, finally alights on the ground. But he has yet
other wiles, which are not used in mid-air. Approaching his mate with
his head erect and body drawn up to its full height, he raises his
wings for an instant high above his head: then allowing them gradually
to droop, he vibrates them, at the same time rapidly moving his legs
like a soldier "marking time."
The curlew seems to prefer the evening for his best efforts. Rising
from the ground with rapid wing-beats, he will "check" suddenly when
near the summit of his ascent; so suddenly as almost to throw himself
backwards. Then, recovering, he will hang poised, kestrel-like, in
mid-air, and pour forth a joyous thrilling, or jodelling, song. Rising
and falling, on quivering wings, or sweeping round in great circles,
and hovering again, he will remain for some considerable time pouring
forth this joyful ripple of song.
The courtship flight of the lapwing is even, if possible, more
interesting. Rising from the ground with slow heavy flaps of his broad
wings--which, it is to be noted, present a remarkable difference
from those of the female, in that the primaries are much longer, so
as to give this portion of the extended wing a conspicuously broader
appearance--as though he had difficulty in getting under way, he
speedily dissipates this impression by a sudden upward rush, an
effortless turn, apparently; and then follows a downward swoop, or
fall, with half-closed wings. To this swoop there succeeds a surprising
change. In an instant the wing-beat is increased to an incredible
speed, causing the body to turn a half, and sometimes even a complete
somersault. But the next instant he is up and away over the ground
with musical wing-beats, tilting and swaying from side to side with
wonderful buoyancy.
[Illustration: Lapwings.]
Throughout, this delightful performance is accompanied by a wild
and joyous song, which seems to be attuned to the somewhat bleak
surroundings. It thrills one even to remember it in later days: and
it defies one to express it in human fashion. It has been as nearly
rendered as any version I have ever seen--and I have seen many--by
Mr. Brock. It is not a whistle, nor is it like any sound that can
be faithfully rendered by the human voice, yet it seems to say
"_whey-willuchooee-willuch-willuch-cooee_." It suffers a break, remarks
Mr. Farren, commenting on this theme, during the flutter of the wings
at the end of the fall, but is picked up at once with a triumphant
"coo-whee, coo-ee," as the bird dashes off at the end of the somersault.
The lapwing is very intolerant of any trespass on his breeding
territory on the part of his neighbours. As soon as the intruder is
sighted, the owner of the territory charges. And the two then mount up
into the air, often to a great height, each striving to get above the
other for a downward swoop. As the one "stoops" at the other, the lower
bird dodges, and so rapidly are the wings moved that they are often
brought smartly together over the back, producing a clapping noise.
Even the black, forbidding raven has his amorous moods. And at such
times he will even outdo the more lively, though irascible lapwing in
the art of aerial somersaults; if somersaults they can be called. For
in the middle of an ordinary spell of flying he will suddenly fold up
his wings and bring them close up to the body, at the same time turning
completely round, as though he were turned on a spit; the body being
held horizontal as the turn is made. For a moment or two there he is
suspended, as it were, between earth and sky, with his back towards
earth, and his breast towards the heavens. Lest he should forget the
manner of the trick, it would seem, he will practice it at times,
during the stern work of chasing intruders from his territory; for he
will brook no competitors on his ground.
The woodpigeon, during the courtship season, makes frequent sallies
into the air for the purpose, apparently, of giving vent to his
exuberant feelings. During such flights he will dart up from the
tree-tops and sail round, high above, in great circles, rising and
falling as he goes, with out-spread wings, every now and then bringing
them over his back with a resounding snap. During such displays the
white bar across the wing is most conspicuous, serving at once to
identify the performer.
Among our native birds, the only other species which habitually, and
especially during the courting season, produce characteristic sounds
during flight, by bringing the wings smartly together over the back,
is the night-jar. But there are certain small passerine birds, known
as mannikins, inhabiting the forests of South America, which have the
shafts of the quill-feathers of the fore-arm enormously thickened. By
means of these transformed and translated "castenets," at will, the
bird can produce a sound which has been likened to the crack of a whip.
So far this discourse has been concerned solely with "courtship"
flights, or flights associated with peculiar sounds, dependent on rapid
movements of the wing in mid-air for their production. And with the
mention of these instances this Chapter might, quite legitimately,
be brought to an end. But it must not. And this, because there are a
number of birds which put their wings, during Courtship season, to very
different purposes. Spectacular flights and evolutions in mid-air do
not appeal to them. They use their wings instead as lures, as a means
of adding intensity to strange poses and pirouettings; whereby they
desire to give expression to the amorous feelings which possess them,
in the hope--if for the moment, we may accord to them human standards
of intention--of arousing kindred emotions in their mates.
Darwin was the first to draw attention to these curious displays.
Which, on the evidence then available, seemed always to be made, and
only to be made, by birds having wings conspicuously coloured. It
seemed as though the possessors of such wings were conscious of their
beauty, and so displayed them that nothing of their glory should be
missed.
The sun-bittern affords a case in point. This bird, a native of
Brazil, is soberly, but very beautifully coloured when at rest; its
plumage presenting an indescribable mixture of black, grey, brown,
bay, and white; blended in the form of spots, bars, and mottlings. But
during times of sexual excitement it will spread out its wings in the
form of a great fan, encircling the long, slender, neck. And in this
position they present a very conspicuous appearance, taking the form
of beautifully graded bands of black, white, and bright grey, forming
patterns which vanish the moment the primaries fall into their place
behind the quills of the fore-arm. But when thus spread the bird seems
to find the greatest delight in displaying their chaste splendour
before his mate. He seems to spread his wings just because he is
conscious of their beauty when thus opened out.
But we need not travel so far as Brazil to find examples of displays
of this kind. Among the birds of our own Islands we can find many
close parallels. The chaffinch and the goldfinch, when seeking to
arouse the sympathy of their mates make much play with their wings, not
only in short "nuptial flights," designed, apparently, to display the
conspicuous and brilliant colouring of the plumage as a whole, but when
perched on some convenient spray. At such times the wing is more or
less completely spread out, as if to reveal, to the fullest possible
advantage, the bright bars and splashes of colour which this extension
alone can bring into being.
Since these gaily coloured vestments seemed always to be associated
with striking, stilted, attitudes, sometimes bordering on the
grotesque, and always to be paraded in the presence of the female,
Darwin drew the inference that they were the outcome of female choice
persistently exercised during long generations. That is to say he
held that, far back in the history of the race, these performers were
soberly clad, as their mates commonly are. Then certain of the males of
these now resplendent species began to develop patches of colour, small
at first, but gradually increasing, generation by generation, in area
and intensity. This progressive splendour, he believed, was due to the
"selective" action of the females, which, from the very first, chose
from among their suitors those who stood out among their fellows by
reason of their brighter plumage. Thus the duller coloured males died
without offspring. On this assumption each succeeding generation would
be, in some slight degree, brighter than the last, until the process of
transformation ended in the glorified creatures we so admire to-day.
It would be foreign to the purpose of this book to pursue this theme at
length. Let it suffice to say that while the "Sexual Selection" theory
still holds good, it has, so to speak, changed its complexion. And this
largely owing to the accumulation of new facts. For the most important
of these we are indebted to the singularly exact and laborious
observations analysed, clarified, and interpreted with remarkable
insight and sagacity of Mr. H. Eliot Howard, one of the keenest
Ornithologists of our time. He has set forth his case, and interpreted
his facts with masterly skill, and there seems no escape from his
conclusions. Briefly, he has shown that birds of quite sober coloration
like the warblers, which formed the basis of his investigations, engage
in displays quite as remarkable, and of precisely the same character
as in birds of gaily coloured plumage. From this it is clear that this
wing-play is not prompted by a more or less conscious desire to display
conspicuously coloured patches of colour, for of colour there is none
save that of the general hue of varying shades of brown, as in the case
of the grasshopper warbler, for example. Nor is the display, apart
from colour, to be regarded as a performance slowly perfected through
long generations through the selection of females, coy and hard to
please. We must regard these "Nuptial flights" and wing-displays, as
the outward and visible signs of a state of ecstatic amorousness on the
part of the males which, by their persistence and frequent recurrence,
at last arouse sympathetic response in the females. They play the
part of an aphrodisiac. Without them there would be no mating. In my
"Courtship of Animals" those who will may pursue this subject further.
[Illustration: _Herons_]
Before closing this Chapter mention must be made of the most remarkable
wing-display to be found among birds, and of the equally remarkable
uses to which they are put. The possessor of these wonderful
appendages, for they are wonderful, is the argus pheasant of the Malay
Peninsula and Borneo. Though efficient for short flights in jungles,
all that is ever required of them, they would be quite useless in
open country where an extended journey had to be made, or escape
attempted from some vigorous enemy. And this because the secondary
wing-quills--the quills attached to the fore-arm--are of enormous
length, making, as we have remarked, sustained flight impossible. They
have, indeed, come dangerously near losing their normal functions
altogether. And this because they have passed over into the category of
specialised "secondary sexual characters." But for the fact that this
bird lives in an environment where food is abundant all the year round,
and can be obtained without any undue exertion, and that there are no
serious enemies to be evaded, it would long since have become extinct.
For this exuberant growth of quill-feathers must be borne all the year
round, though they are not required to function in their later role,
save during the period of courtship.
Their great length is not their only striking feature, or even their
chief feature. This, indeed, is represented by their extraordinary
coloration. For each feather bears along its outer web a series of
"ocelli," so coloured as to look like a series of dull gold balls
lying within a deep cup. Outside the ocelli run numerous pale yellow
longitudinal stripes on a nearly black background. The inner web is
of a delicate greyish brown hue, shading into white and relieved by
innumerable black spots, while the tips of the quills have white spots
bordered with black. The primaries, too, are most exquisitely coloured,
though in the matter of size they are not very exceptional. These,
indeed, are the only true flight feathers.
The full beauty and significance of the coloration of these feathers
can only be appreciated during periods of display. Then the two wings,
in some indescribable manner, are opened out so as to form a huge
circular screen, concealing the whole of the rest of the body. The
effect produced from the human standpoint is one of great beauty, after
the first burst of astonishment has spent itself. His mate is less
easily moved. Perchance "familiarity breeds contempt." At any rate it
is only after persistent and frequent attempts to charm her to his will
that success rewards him.
Those who have the good fortune to be able to make frequent visits to
the Zoological Gardens in London may, with great good fortune, and at
rare intervals, have an opportunity of witnessing such a display, and
of studying in detail these wonderful wings. They are wonderful, not
merely because of the manner of their display, or of their colouring,
but also because in them we see ornament pushed to its furthest limit
since, as wings, they have become well nigh useless, and therefore
almost dangerous to the well-being of their possessors.
[Illustration: Sunbittern Displaying.]