CHAPTER V.

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.

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.

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.

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.