Kitabı oku: «Nests and Eggs of Birds of The United States», sayfa 13

Plate XXVI. – POLIOPTILA CÆRULEA, (Linn.) Sclater. – Blue-gray Gnatcatcher

When the first breath of spring, on zephyr wings, blows over the South, laden with dewy moisture and balm from regions beyond the Gulf, this tiny speck of bird-life feels the glowing influence, and hails it with delight. Weary and restless, it seeks to break away from its winter-home, or change the monotony of its existence. While some are inclined to newness of climate, and leisurely wend their way northward, others are happy and contented where they are. Those, imbued with a spirit of migration, quit their less ambitious neighbors in March or April, to spend their summers abroad. All reach their destination by three great routes. Those on the east, that winter in the isles to the southward, follow the trend of the great Atlantic slope as far north as the valley of the Connecticut and kindred latitudes. Others, doubtless, from our southernmost States and the Mexican possessions, pursue a central direction, one part passing through the eastern half of the Mississippi Valley to the Lake country, and the other ceasing from their toilsome journey when the northern frontiers of Nebraska and Iowa are attained. While the western wave, so to speak, collect from their winter-retreats in the valleys of the Colorado and Rio Grande Rivers and follow these streams to their headwaters, or turn aside from their course and make their way through the fertile slopes of the Pacific to the latitude of 42 degrees.

Though an early migrant, yet, by reason of the tardiness of its movements, this species does not arrive in the Middle States until the last of April, or the beginning of May. In Maryland and Virginia, according to Coues, its advent occurs during the early part of April. The Carolinas, Northern Alabama and Tennessee witness its appearance about the fifteenth of March when the season is not retarded by a long, cold winter, and the Northern Central States, towards the close of the ensuing month, which, by some inexplicable cause, seems also to be the date of its coming in the great Colorado Basin.

Appearing at a time when the trees are beginning to clothe themselves in shimmering robes of green, and often before the oaks and hickories have burst their tumid buds into the rich drapery of foliage which is to cover their unsightly nakedness, our little friend is none the less welcome. From the tall tree-tops we are first made aware of his presence by the shrill, wiry notes with which he salutes the morn, and which he is accustomed to utter during the livelong day as he moves in and out among the branches in tireless pursuit of prey. Not a tree-crevice escapes his keen scrutiny. While thus eagerly prying into every cranny or crack that meets his gaze in quest of the lurking culprit, should the buzz of a fly or the hum of a beetle be borne to his hearing, in an instant he is off with a dash that is wonderful to behold, and the unhappy insect is made to repent the folly and temerity of its action. At such times, his behavior seems to be all hurry and bustle, as though the work of a life must be crowded into a few short days.

We have but pictured to the minds of our readers the selfish side of his character, as manifested in the uncontrollable rapacity which sways him. But when the finer and more ennobling impulses of his nature, stimulated by returning warmth, have once more gained the mastery, a milder grace attends his every movement, and sweeter accents attune his voice. We no longer hear those peculiar sounds, which to the human ear resemble tsee-tsee-tsee, repeated in rapid succession, and which, a few short weeks before, were everywhere to be heard – a fit accompaniment to his reckless life – but instead, are regaled with the sweetest, tenderest music. This is so low, that to appreciate its effect, the auditor must be but a few yards distant from the tree which our modest vocalist has selected to be the scene of his endeavors. So well sustained is the effort, and, above all, so faultlessly rendered, that the most austere critic could hardly fail to assign the performer a high place among the feathered choir.

Like many of his kith, he does not seek the bare branch of some tall tree, where he can be seen, and thrill the air of vale and wood around with ear-splitting utterances. He despises such notoriety. Hid away in the leafy canopy that wreathes the brow of some gnarled oak, he loves to take his stand, and there pour out his soul in all the ecstasy of subdued song. Unpretentious as his music may be, and undervalued for its lack of force by the vast choir of singers around, yet it has a depth of power and feeling, which, as it is borne aloft upon the bosom of the gentle air, strikes the ears of some timid, modest creature, and startles the slumbering chords of her being into harmony. Life to her now acquires new vitality and enjoyment. With heart beating high with rapturous emotions, and urged by an irresistible desire, she betakes herself on swiftest pinions to the spot whence emanate the sounds. As she nears it, the music comes to her with fuller distinctness, and sends the heart-throbs following one another in happy, swift succession. The singer does not abate his efforts, but keeps them up with scarce an intermission, until they elicit a response, or the gentle, loving one is wafted to his immediate presence. On the reception of a reply, his movements are restless and animated. But let the object of his thoughts but flit before his excited vision, and in a moment he is by her side. In a variety of actions which, from a human standpoint, seem meaningless and frivolous, he conveys to her his love, and the boundless appreciation of her worth. This done, he next attempts a song, which seems to soothe her hitherto agitated feelings, and awakens confidence and resignation. He is not slow in perceiving the advantage thus acquired, and, consequently, follows it up with other advances, which completely place her at the disposal of his mercy and power. Conquered at last, she yields herself a willing subject to the potency of love, and becomes his wedded wife.

The selection of a home-spot now claims the attention. High, open woods are preferred for this purpose, although trees along the borders of streams, and in low, damp situations, are sometimes chosen. There seems to be no particular fancy for one tree more than another, provided it be lichen-clad. Those whose branches are thus ornamented, the oak especially, will be found to be more frequently favored. Instances are known, however, of nests being placed upon the maple, a tree remarkable for its dearth of such vegetation. Having chosen the site, the erection of a dwelling is next in order. Accordingly, the pair set about this business.

The time chosen for the work is generally the month of May, when insect-life runs riot, and mother earth is ablaze with a thousand floral beauties, the free-will offering of the queen that now presides. From its dawn to its close, these curious structures may be seen in various stages of completion, with eggs and without, tenantless and occupied. Specimens from Texas, with egg-complements, have been found on or near the fifteenth, which had doubtless been commenced two weeks before. Others from New Jersey and Pennsylvania contained incubated eggs as late as the twenty-eighth, while one from Eastern Tennessee with two fresh eggs was found on the sixth of the month following. But this may have been a case where the early efforts of the birds to nest had been prevented by circumstances beyond their control. Reports from the extreme northern and western limits of the range of these birds point to the same conclusion.

The height which these nests occupy above the ground varies with the locality. In some places they seldom attain a greater elevation than ten feet, but, in the majority of cases, this limit is exceeded, and the heights of fifty, and even sixty feet, are reached. There is less variation in form noticeable, their shape being generally that of a truncated cone. One nest before us from the South differs somewhat from this figure, and may be pronounced as inversely conical. The position, too, is quite uniform. Most of them are placed among slender branches, to which they are woven by the ingenuity of the architects, and, although non-pensile, are the sport of every breeze. But so securely are they fastened, that to dislodge them from their moorings, is a matter of no little difficulty.

Though jostled most readily by the winds, and in danger of destruction, yet, by a wise provision of instinct, their contents are insured against accident. This is prevented not so much by the depth of the cavity, as by the purse-like contraction of the rim.

Few structures of bird-architecture are more handsome than the home of this little Gnatcatcher, and none so worthily excite our wonder and admiration. Like the nests of the Humming-bird and Wood Pewee, it is a perfect model of beauty and design. So cunningly contrived a structure, and one so comfortably, durably and tastefully arranged, would doubtless be attributed by us to the work of superior beings, were we not acquainted with the artificers. In the foregoing particulars, it stands almost unrivalled. Like the colors which glow upon the bosom of the mother of pearl, it must be seen to be fully appreciated. No description, however faithfully portrayed, can give an adequate conception of its beauty. But we shall make the attempt. Even the picture gives but a meagre idea of the elegance of this cosy chamber. Its walls are of felt, closely and compactly woven, and made of slender stems of grass, the down of thistles, spider's webs, and vegetable-like fibres. As if dissatisfied with such a fine piece of mechanism, our little architects must needs go further. With a love for the beautiful and picturesque, they almost startle the beholder by investing the exterior with a fine stucco-work of bluish-gray lichens which serves the two-fold purpose of ornamentation and protection. So like a natural excrescence does the nest now appear, that only the experienced eye can detect the 'difference. Compared with the size of its tiny builder, who measures but four and three-tenths inches from tip of bill to caudal extremity, the nest seems bulky. These structures are, however, by no means uniform in size. A specimen from New Jersey has a width of two and seven-eighths inches, and a height of three. Another from Texas measures two and five-eighths inches in length, and but two and a half in external diameter. The smallest we have seen are from Tennessee and California. The former has a width of two and a quarter inches, and a height of two and five-eighths, while the latter differs therefrom only in length, being half an inch less. The cavities offer less striking differences, varying slightly from one and a half inches in either direction. In composition the Western nest presents some points of difference. The exterior is composed of yellowish-green and greenish-gray lichens, specifically distinct from Eastern specimens, a slight intersprinkling of brown catkins, feathers, cobwebs, and small bits of vegetable stems. The inside does not present much variation, but is lined with feathers, horse-hairs and vegetable wool, as many of our own are. When feathers are utilized for a lining, the quills are generally placed in the walls of the nest, only the soft plume-like parts being allowed to come into contact with the eggs. The nest from California was found by Prof. Ever-mann, in the vicinity of Santa Paula, during the summer of 1881. It is the prettiest, as well as the most elaborately perfected nest which we have yet seen. The one from which the drawing was made, while less artistic, deserves mention, from the peculiar position which it occupies, being wedged in between two diverging branches from a sweet-gum, and fastened thereto by cobwebs passing from its outside to the wing-like expansions of the wood.

Such finished and complicated structures are assuredly not the work of a few hours, but the labor of unwearied perseverance and industry upon the part of the builders for a week. No division of the work is allowed, but each bird toils as suits its inclination. Whether the rearing of the fabric proper with its finely-felted walls, or the laying on of the tiles afterwards, requires the longer time to accomplish, it is difficult to say. Our experience teaches that the latter is the more trying and difficult task, and consumes one-third more time. It must not be presumed that the builders work steadily through the entire day. This is not the case. Rest, recreation, and the procurement of food, are matters that require attention, and prolong the labor.

Having finished their home, the female is not slow in providing it with tenants. From four to six eggs are deposited in as many days, and incubation entered into. This lasts fourteen days, and is as much the work of one sex as the other. While thus occupied, the birds are jealous of their property, and resent all intrusions with a valor worthy of admiration. This is especially the case when their home is visited by the Cowbird. So determined and fierce are the attacks which they wage against these birds, that in the melee which ensues, their fragile home is often entirely destroyed. In Cooke County, Texas, where this Gnatcatcher is abundant, fully half the nests that have been found by Mr. Ragsdale, the narrator of this fact, are despoiled before completion, and, in many instances, completely obliterated. But let the intruder be some conscienceless collector, knowing that resistance is useless the birds do not make a stand, but seek some safe spot where they can observe the proceedings. But as soon as the premises have been deserted they return, and if the home remains untouched, resume possession as though nothing had happened. In the event of desecration, they forsake the spot with sorrow and reluctance, and try their fortunes elsewhere. But a single brood is raised, although the tardiness of some pairs to nidificate has led to the belief that in some seasons the species may be double-brooded.

The young birds, for a week or ten days subsequent to hatching, are quite weak and tender, and but for the attention and care bestowed by parental love, would quickly perish. Endowed by Nature with vigorous appetites, and being blessed with kind and thoughtful parents, they are soon able to help themselves. Their food at first consists of larvæ of various kinds, but chiefly those of a lepidopterous character, and small diptera. With age comes an increase in the quantity and character of their food, and at the age of four weeks they desert the home-shelter, and forage in common with their parents. Thus they spend their lives, careless and happy, until the first appearance of the "sere and yellow leaf" in September warns them of the growing scarcity of food-stuffs, and bids them retire to the groves of our southernmost States, or to scenes beyond the Mexic line.

Their eggs are oval in form, and slightly pointed. In ground-color they are white, and spotted and blotched with reddish-brown, slate and lilac. Cabinet specimens, however, show sometimes a faint bluish- or greenish-white tint. The markings, though varying considerably, are uniformly distributed. In size, there is noticeable but little variation in specimens from diverse localities; eggs from Michigan differing but slightly from those from Texas, and these sustaining the same' relation to sets from Pennsylvania. The average dimensions of a clutch of four from New Jersey are .59 by .48 inches. The depth of the nest precludes us from showing the eggs in situ. We are therefore compelled to give a drawing below, which will be found to be of the natural proportions. The female-bird, which is placed in close contiguity to the nest, may be easily distinguished from her mate, by the absence of black upon the head.

Plate XXVII. – PASSERINA CIRIS, (Linn.) Gray. – Nonpareil; Painted Bunting

For variety and brilliancy of coloring none of our North American finches can compare with the one which constitutes the subject of this sketch. The euphonious French title by which it is designated has been most aptly chosen. For, verily, it is the nonpareil of avian beauty. Nature seems to have spared no pains in making this her handiwork the perfection of artistic design and ornamentation. Such an array of colors, and the beautiful harmony which characterizes their blending, bespeak no mean, unskilful painter, but a master-hand, before whose paltriest, weakest efforts the noblest of man's productions sinks into insignificance.

Contrasted with its less showy associates that frequent the same delightful, sunny landscapes to breed, this lovely species seems altogether out of place. It is a fitter denizen for realms beyond the tropic, where the broad-leaved banana hangs its clustering, golden flagons temptingly to the gaze, and where many-hued, various life rejoices in wanton prodigality.

Though reared amid the rich savannas and fertile slopes of South Carolina, and the belt of country thence westward to the Pecos River, of Texas, it is only a temporary sojourner. With the first breath that comes from the north, in the fall, it takes its departure, and wings its flight to warmer latitudes. The land of the Aztec, and the warm isles of the sea to the southward, are its destination. A few individuals, fond of travel and change of scenery, do not, however, pause from their journey until they have reached the Isthmus which weds the two great halves of the American continent.

As spring approaches, an anxious spirit of restlessness seizes the males, which sooner or later communicates itself to the opposite sex. This is manifest some time before setting out. But guided by a never-erring instinct, they curb their impatience, and thus bring it under restraint. Hence, like many kindred species, they are not very early comers. The middle of April – the season of sunshine and of showers – usually dates their first appearance in the Gulf States, and from this time they are not slow in reaching their most northern homes. The lords, in their spruce and rich attires, generally lead their sober, unadorned companions by several days, and may be seen in low thickets along the borders of streams, among the rice plantations, or in the vicinity of the sad, cheerless sea. Fond of the lowlands, at such times, one would imagine that such situations would have a depressing effect, and render them gloomy and despondent. But this is far from being the truth. Almost from the beginning of their arrival, they are endowed with the propensity to sing, even before their partners have come. From the summit of a Wayside bush, a fence-rail, or from out the hedges of some suburban villa, their rich, mellifluent warblings may be heard to the infinite pleasure and joy of the weary pedestrian. These musical utterances resemble the notes of the common Indigo Bird, but lack their energy and power of sustentation. It is not now that their songs are heard to the best advantage, but when the season of mating occurs, a fortnight later. They are then in their happiest moods. The presence of the dear ones excites within them the passion of love, and calls forth the highest capabilities of their natures. In the days of Wilson these were recognized, and many a male-bird was captured and confined to a cage, by the French inhabitants of the lower parishes of Louisiana, not more for the splendor of his plumage, the docility of his manners, than for the sweetness of his song. Great numbers were not only decoyed into traps, and other devices, to satisfy the growing desire for such pets at home, but hundreds were shipped to other countries. But it is only of late years that their introduction into our northern cities has been an object of pecuniary profit, and now almost every fancier's store is made to rejoice with the dulcet strains of this beautiful and active little Finch.

Coming back from this digression, let us view, for a few moments, the character of the sexes, and their behavior at the time of mating. Naturally pugnacious in the presence of a rival, the male is all gentleness and kindness when in the society of females, and exerts his best efforts to please and conciliate. The character of the female is the exact antithesis of his, and wins admiration by its sweetness and simplicity. Modest and plain in dress, she is equally artless and unassuming in demeanor. The courage which she sees displayed by her masculine protector does not impress her with feelings of awe and timidity, but challenges her admiration, confidence and esteem. Knowing that such conduct, so thoroughly devoid of civility as it seemeth, is but the outgrowth of jealous affection, she is drawn to him by an influence which she cannot control nor resist. Consequently, his road to happiness and bliss is one untrammeled by the cares and trials which beset the paths of less fortunate claimants for female favors. He has only to present his suit accompanied by the usual protestations of love, to have it honored with a prompt and willing acceptance. While these amours are being enacted, a rival dare not intrude upon the hallowed precincts. Such an act of temerity would but be the prelude to a bitter encounter, which must result in one or the other of the combatants being driven away discomfited and disgraced. The females are never known to take part in these affrays, but maintain, at a safe distance, an attitude of passivity. So well known to the bird-dealers of New Orleans is this peculiar disposition about which we have been writing, that advantage is taken thereof for the purposes of the trade. It is on this wise: A mounted male-bird is placed in a position of defence upon the platform of a trap-cage. As soon as discovered, it is attacked by a male-bird with determined vigor, and even after the trap is sprung, and the assailant has become an unwilling prisoner, these assaults are continued with zealous and unremitting pertinacity.

Events now follow each other in close succession. Pairing being solemnized, the birds seek themselves out a spot for a home. Low growths are usually selected. In Texas, thick mezquite-bushes and live oaks, and, in Louisiana, orange hedges, bramble and blackberry bushes, and, occasionally, the lower branches of trees are occupied. The height above the ground seldom exceeds ten feet, the usual elevation being from four to five feet. A crotch is generally the recipient of the fabric, except in cases where tangled bushes are used, when their booked and prong-like branches serve as girders of support.

By the first of May, everything being in readiness, the ground-floor of the domicile is laid, and little by little the walls are raised, through the cool, united efforts of the two patient workers. By no means as artistic as some we have already described, yet it is, withal, a neat, comfortable and staid structure. The materials of composition are not at all varied, but usually consist of dried grass, vegetable stems, leaves in small quantities, fine rootlets, and silk of caterpillars, on the exterior, and horse-hairs, or the slender culms of grasses, on the interior. In many instances, the stems are clothed with long hairs, which serve as points of attachment to the cottony and silken fibres which bind the coarser substances together. A nest before us presents to the unaided vision a slight lustrous appearance from the vast numbers of membranous dessepiments or partitions – relics of seed-vessels that are adherent to most of the stems. The cavity has an even, unragged margin, which is due to the great pains taken in the disposition of the flaxen fibres which, in a great measure, compose it. On the whole, the outside is remarkably smooth and uniform, while the interior, with its circularly-arranged layers, is a perfect model of elegance and comfort. The height of the nest which we have figured, and the same may be reasonably true of all such structures, is two and one-tenth inches, and the width, two and nine-tenths. The opening is one and nine-tenths inches in diameter, and nearly the same in depth. This nest was collected in Comal County, Texas, on the ninth of May, 1881, and is a fair representation of the typical structure. In the drawing it is shown upon a live oak branch, of natural dimensions, and with the female in the distance. Her partner is figured in the foreground, and may be readily distinguished. His head and neck are a beautiful ultramarine-blue, excepting a narrow patch from the chin to the breast, which inclines to vermillion-red. The eye-lids, and the under parts generally, are of this latter shade, while the rump is tinged with purplish. All other parts (the lesser wing coverts, tail feathers, and outer webs of quills excluded) are green, excepting the interscapular region, which reflects a gloss of yellow, while the undescribed portions are purplish-blue. What a contrast to the female-bird, which can only boast of a dark green habit with a yellowish front. The young are the likeness of their mothers. The length of the adult is five and a half inches, and expanse of wings, two and seven-tenths.

From the first commencement of the home, to its final completion for occupancy, not more than a week elapses, and the female is ready to deposit her first instalment of eggs. This is succeeded by similar payments, to the number of four or five, of the great debt which Nature demands of her. Having settled the last obligation, she nestles down into her cosy chamber with the determination to watch and wait for the priceless treasures which she knows must be her ultimate reward. While she is thus about her agreeable business, her proud and dignified companion is abroad in quest of enjoyment and luxurious living. He seems to be the happiest of fellows. Could you hear him as he wends his way among the orangeries, in the full tide of song, you could not help feeling that he is the most thoughtless and cruel fellow of your acquaintance. Never a care does he appear to have for the patient little being who is sitting her life away, in order that his loneliness and hers shall be blessed with a happy house-full of children. But it is otherwise. Seemingly unmindful, he is at heart a clever being. Let but his home be invaded, and he is on the spot in an instant, ready to avenge any wrong, in his own summary manner, that may be attempted or committed. But his loving and Quaker-like housewife is possessed of greater forbearance. Trustful and gentle, she will often permit herself to be lifted from the nest rather than expose her jewels to the greed and cruelty of an unsympathizing world. While a comparatively close prisoner at home for a period of fourteen days during the incubating process, she, however, does occasionally quit its shadows, when sorely pressed by hunger, but only for a brief time.

The appearance of the young is the inauguration of a change in the male's demeanor. Proud of his progeny, he breaks away from his hitherto aimless habits, and makes amends therefore by becoming a very dutiful and affectionate parent. With equal zeal he assists his partner in collecting the various insects which contribute to their nourishment. As long as their helplessness continues, he may be thus observed. But when, after a period of thirteen or fourteen days, the young are able to quit the nest, he abates his care in a measure, and teaches them to help themselves. When sufficiently matured, like their parents, they feed upon rice, the seeds of figs, and the various grains peculiar to their native haunts, as well as upon insects. The young females soon acquire their proper dress, but the males, on the contrary, are slow in arriving at the same condition. Four years, at the farthest, are necessary to bring about the final change.

The eggs are rounded-oval, of a white or grayish color, and beautifully marked with brown and violet-colored spots chiefly about the larger extremities, but more scattered, smaller and paler ones over the rest of the eggs. In some specimens from Texas and Louisiana, the violet spots predominate, thus contrasting in a marked manner with normal forms. The average dimensions of a set from Texas are as follows: .85 by .60,80 by .60,80 by .60 and .85 by .60 inches. Another set from Comal County, of the same State, measure respectively .81 by .03,81 by .63,75 by .63 and .75 by .62 inches. Nests with eggs, found as late as June 21st, seem to warrant the belief that two broods are annually raised, but this needs confirmation. In confinement, as many as three are of common occurrence.