Читать книгу My Studio Neighbors - Gibson William Hamilton - Страница 2

SHOW has that "blessed bird" and "sweet messenger of spring," the "cuckoo," imposed upon the poetic sensibilities of its native land!

And what is this cuckoo which has thus bewitched all the poets? What is the personality behind that "wandering voice?" What the distinguishing trait which has made this wily attendant on the spring notorious from the times of Aristotle and Pliny? Think of "following the cuckoo," as Logan longed to do, in its "annual visit around the globe," a voluntary witness and accessory to the blighting curse of its vagrant, almost unnatural life! No, my indiscriminate bards; on this occasion we must part company. I cannot "follow" your cuckoo—except with a gun, forsooth—nor welcome your "darling of the spring," even though he were never so captivating as a songster.

The European Cuckoo

The song and the singer are here identical and inseparable, to my prosaic and rational senses; for does not that "blithe new-comer," as Tennyson says, "tell his name to all the hills"—"Cuckoo! Cuckoo!"

The poet of romance is prompted to draw on his imagination for his facts, but the poet of nature must first of all be true, and incidentally as beautiful and good as may be; and a half-truth or a truth with a reservation may be as dangerous as falsehood. The poet who should so paint the velvety beauty of a rattlesnake as to make you long to coddle it would hardly be considered a safe character to be at large. Likewise an ode to the nettle, or to the autumn splendor of the poison-sumac, which ignored its venom would scarcely be a wise botanical guide for indiscriminate circulation among the innocents. Think, then, of a poetic eulogium on a bird of which the observant Gilbert could have written:

"This proceeding of the cuckoo, of dropping its eggs as it were by chance, is such a monstrous outrage on maternal affection, one of the first great dictates of nature, and such a violence on instinct, that had it only been related of a bird in the Brazils or Peru, it would never have merited our belief.... She is hardened against her young ones as though they were not hers.... 'Because God hath deprived her of wisdom, neither hath He imparted to her understanding.'"

America is spared the infliction of this notorious "cuckoo." Its nearest congeners, our yellow-billed and black-billed cuckoos, while suggesting their foreign ally in shape and somewhat in song, have mended their ways, and though it is true they make a bad mess of it, they at least try to build their own nest, and rear their own young with tender solicitude. The nest is usually so sparse and flimsy an affair that you can see through its coarse mesh of sticks from below, the fledglings lying as on a grid-iron or toaster; and it is, moreover, occasionally so much higher in the centre than at the sides that the chicks tumble out of bed and perish. Still, it is a beginning in the right direction.

The Yellow-billed Cuckoo

Yes, it would appear that our American cuckoo is endeavoring to make amends for the sins of its ancestors; but, what is less to its credit, it has apparently found a scapegoat, to which it would ever appear anxious to call our attention, as it stammers forth, in accents of warning, "c, c, cow, cow, cow! cowow, cowow!" It never gets any further than this; but doubtless in due process of vocal evolution we shall yet hear the "bunting," or "black-bird," which is evidently what he is trying to say.

Owing to the onomatopoetic quality of the "kow, kow, kow!" of the bird, it is known in some sections as the "kow-bird," and is thus confounded with the real cow-bird, and gets the credit of her mischief, even as in other parts of the country, under the correct name of "cuckoo," it bears the odium of its foreign relative.

For though we have no disreputable cuckoo, ornithologically speaking, let us not congratulate ourselves too hastily. We have his counterpart in a black sheep of featherdom which vies with his European rival in deeds of cunning and cruelty, and which has not even a song to recommend him—no vocal accomplishment which by the greatest of license could prompt a poet to exclaim,

"I hear thee and rejoice,"

without having his sanity called in question.

The cow-blackbird, it is true, executes a certain guttural performance with its throat—though apparently emanating from a gastric source—which some ornithologists dignify by the name of "song." But it is safe to affirm that with this vocal resource alone to recommend him he or his kind would scarcely have been known to fame. The bird has yet another lay, however, which has made it notorious. Where is the nest of song-sparrow, or Maryland yellow-throat, or yellow warbler, or chippy, that is safe from the curse of the cow-bird's blighting visit?

And yet how few of us have ever seen the bird to recognize it, unless perchance in the occasional flock clustering about the noses and feet of browsing kine and sheep, or perhaps perched upon their backs, the glossy black plumage of the males glistening with iridescent sheen in the sunshine.

"Haow them blackbirds doos love the smell o' thet caow's breath!" said an old dame to me once in my boyhood. "I don't blame um: I like it myself." Whether it was this same authority who was responsible for my own similar early impression I do not know, but I do recall the surprise at my ultimate discovery that it was alone the quest of insects that attracted the birds.

Browsing Kine

Upon the first arrival of the bird in the spring an attentive ear might detect its discordant voice, or the chuckling note of his mischievous spouse and accomplice, in the great bird medley; but later her crafty instinct would seem to warn her that silence is more to her interest in the pursuit of her wily mission. In June, when so many an ecstatic love-song among the birds has modulated from accents of ardent love to those of glad fruition, when the sonnet to his "mistress's eyebrow" is shortly to give place to the lullaby, then, like the "worm i' the bud," the cow-bird begins her parasitical career. How many thousands are the bird homes which are blasted in her "annual visit?"

Stealthily and silently she pries among the thickets, following up the trail of warbler, sparrow, or thrush like a sleuth-hound. Yonder a tiny yellow-bird with a jet-black cheek flits hither with a wisp of dry grass in her beak, and disappears in the branches of a small tree close to my studio door. Like the shadow of fate the cow-bird suddenly appears, and has doubtless soon ferreted out her cradle.

In a certain grassy bank not far from where I am writing, at the foot of an unsuspecting fern, a song-sparrow has built her nest. It lies in a hollow among the dried leaves and grass, and is so artfully merged with its immediate surroundings that even though you know its precise location it still eludes you. Only yesterday the last finishing-touches were made upon the nest, and this morning, as I might have anticipated from the excess of lisp and twitter of the mother bird, I find the first pretty brown-spotted egg.

Surely our cow-bird has missed this secret haunt on her rounds. Be not deceived! Within a half-hour after this egg was laid the sparrow and its mate, returning from a brief absence to view their prize, discover two eggs where they had been responsible for but one. The prowling foe had already discovered their secret; for she, too, is "an attendant on the spring," and had been simply biding her time. The parent birds once out of sight, she had stolen slyly upon the nest, and after a very brief interval as slyly retreated, leaving her questionable compliments, presumably with a self-satisfied chuckle. The intruded egg is so like its fellow as to be hardly distinguishable except in its slightly larger size. It is doubtful whether the sparrow, in particular, owing to this similarity, ever realizes the deception. Indeed, the event is possibly considered a cause for self-congratulation rather than otherwise—at least, until her eyes are opened by the fateful dénouement of a few weeks later. And thus the American cow-bird outcuckoos the cuckoo as an "attendant on the spring," taking her pick among the nurseries of featherdom, now victimizing the oriole by a brief sojourn in the swinging hammock in the elm, here stopping a moment to leave her charge to the care of an indigo-bird, to-morrow creeping through the grass to the secreted nest of the Maryland yellow-throat, or Wilson's thrush, or chewink. And, unaccountable as it would appear, here we find the same deadly token safely lodged in the dainty cobweb nest of the vireo, a fragile pendent fabric hung in the fork of a slender branch which in itself would barely appear sufficiently strong to sustain the weight of a cow-bird without emptying the nest.

Indeed, the presence of this intruded egg, like that of the European cuckoo in similar fragile nests, has given rise to the popular belief that the bird must resort to exceptional means in these instances. Sir William Jardine, for instance, in an editorial foot-note in one of Gilbert White's pages, remarks:

"It is a curious fact, and one, I believe, not hitherto noticed by naturalists, that the cuckoo deposits its egg in the nests of the titlark, robin, and wagtail by means of its foot. If the bird sat on the nest while the egg was laid, the weight of its body would crush the nest and cause it to be forsaken, and thus one of the ends of Providence would be defeated. I have found the eggs of the cuckoo in the nest of a white-throat, built in so small a hole in a garden wall that it was absolutely impossible for the cuckoo to have got into it."

In the absence of substantiation, this, at best, presumptive evidence is discounted by the well-attested fact that the cuckoo has frequently been shot in the act of carrying a cuckoo's egg in its mouth, and there is on record an authentic account of a cuckoo which was observed through a telescope to lay her egg on a bank, and then take it in her bill and deposit it in the nest of a wagtail.

There is no evidence to warrant a similar resource in our cow-bird, though the inference would often appear irresistible, did we not know that Wilson actually saw the cow-bird in the act of laying in the diminutive nest of a red-eyed vireo, and also in that of the bluebird.

And what is the almost certain doom of the bird-home thus contaminated by the cow-bird?

A Greedy Foster-child

The egg is always laid betimes, and is usually the first to hatch, the period of incubation being a day or two less than that of the eggs of the foster-parent. And woe be to the fledglings whom fate has associated with a young cow-bird! He is the "early bird that gets the worm." His is the clamoring red mouth which takes the provender of the entire family. It is all "grist into his mill," and everything he eats seems to go to appetite—his bedfellows, if not thus starved to death, being at length crushed by his comparatively ponderous bulk, or ejected from the nest to die. It is a pretty well established fact that the cuckoo of Europe deliberately ousts its companion fledglings—a fact first noted by the famous Dr. Jenner. And Darwin has even asserted that the process of anatomical evolution has especially equipped the young cuckoo for such an accomplishment—a practice in which some accommodating philosophic minds detect the act of "divine beneficence," in that "the young cuckoo is thus insured sufficient food, and that its foster-brothers thus perish before they have acquired much feeling."

The following account, written by an eye-witness, bears the stamp of authenticity, and is furthermore re-enforced by a careful and most graphic drawing made on the spot, which I here reproduce, and fully substantiates the previous statement by Dr. Jenner. The scene of the tragedy was the nest of a pipit, or titlark, on the ground beneath a heather-bush. When first discovered it contained two pipit's eggs and the egg of a cuckoo.

"At the next visit, after an interval of forty-eight hours," writes Mrs. Blackburn, "we found the young cuckoo alone in the nest, and both the young pipits lying down the bank, about ten inches from the margin of the nest, but quite lively after being warmed in the hand. They were replaced in the nest beside the cuckoo, which struggled about till it got its back under one of them, when it climbed backward directly up the open side of the nest and pitched the pipit from its back on to the edge. It then stood quite upright on its legs, which were straddled wide apart, with the claws firmly fixed half-way down the inside of the nest, and, stretching its wings apart and backward, it elbowed the pipit fairly over the margin so far that its struggles took it down the bank instead of back into the nest. After this the cuckoo stood a minute or two feeling back with its wings, as if to make sure that the pipit was fairly overboard, and then subsided into the bottom of the nest.

"I replaced the ejected one and went home. On returning the next day, both nestlings were found dead and cold out of the nest.... But what struck me most was this: the cuckoo was perfectly naked, without a vestige of a feather, or even a hint of future feathers; its eyes were not yet opened, and its neck seemed too weak to support the weight of the head. The pipit had well-developed quills on the wings and back, and had bright eyes, partially open, yet they seemed quite helpless under the manipulations of the cuckoo, which looked a much less developed creature. The cuckoo's legs, however, seemed very muscular; and it appeared to feel about with its wings, which were absolutely featherless, as with hands, the spurious wing (unusually large in proportion) looking like a spread-out thumb."

Considering how rarely we see the cow-bird in our walks, her merciless ubiquity is astonishing. It occasionally happens that almost every nest I meet in a day's walk will show the ominous speckled egg. In a single stroll in the country I have removed eight of these foreboding tokens of misery. Only last summer I discovered the nest of a wood-sparrow in a hazel-bush, my attention being attracted thither by the parent bird bearing food in her beak. I found the nest occupied, appropriated, monopolized, by a cow-bird fledgling—a great, fat, clamoring lubber, completely filling the cavity of the nest, the one diminutive, puny remnant of the sparrow's offspring being jammed against the side of the nest, and a skeleton of a previous victim hanging among the branches below, with doubtless others lost in the grass somewhere in the near neighborhood, where they had been removed by the bereaved mother. The ravenous young parasite, though not half grown, was yet bigger by nearly double than the foster-mother. What a monster this! The "Black Douglass" of the bird home; a blot on Nature's page!

As in previous instances, observing that the interloper had a voice fully capable of making his wants known, I gave the comfortable little beast ample room to spread himself on the ground, and let the lone little starveling survivor of the rightful brood have his cot all to himself.

And yet, as I left the spot, I confess to a certain misgiving, as the pleading chirrup of the ousted fledgling followed me faintly and more faintly up the hill, recalling, too, the many previous similar acts of mine—and one in particular, when I had slaughtered in cold blood two of these irresponsibles found in a single nest. But sober second thought evoked a more philosophic and conscientious mood, the outcome of which leading, as always, to a semi-conviction that the complex question of reconciliation of duty and humanity in the premises was not thus easily disposed of, considering, as I was bound to do, the equal innocence of the chicks, both of which had been placed in the nest in obedience to a natural law, which in the case of the cow-bird was none the less a divine institution because I failed to understand it. Such is the inevitable, somewhat penitent conclusion which I always arrive at on the cow-bird question; and yet my next cow-bird fledgling will doubtless follow the fate of all its predecessors, the reminiscent qualms of conscience finding a ready philosophy equal to the emergency; for if, indeed, this parasite of the bird home be a factor in the divine plan of Nature's equilibrium, looking towards the survival of the fittest and the regulation of the sparrow and small-bird population, which we must admit, how am I to know but that this righteous impulse of the human animal is not equally a divine, as it is certainly a natural institution looking to the limitations of the cow-bird? One June morning, a year or two ago, I heard a loud squeaking, as of a young bird in the grass near my door, and, on approaching, discovered the spectacle of a cow-bird, almost full-fledged, being fed by its foster-mother, a chippy not more than half its size, and which was obliged to stand on tiptoe to cram the gullet of the parasite.

The victims of the cow-bird are usually, as in this instance, birds of much smaller size, the fly-catchers, the sparrows, warblers, and vireos, though she occasionally imposes on larger species, such as the orioles and the thrushes. The following are among its most frequent dupes, given somewhat in the order of the bird's apparent choice: song-sparrow, field-sparrow, yellow warbler, chipping-sparrow, other sparrows, Maryland yellow-throat, yellow-breasted chat, vireos, worm-eating warbler, indigo-bird, least-flycatcher, bluebird, Acadian flycatcher, Canada flycatcher, oven-bird, king-bird, cat-bird, phœbe, Wilson's thrush, chewink, and wood-thrush.

But one egg is usually deposited in a single nest; the presence of two eggs probably indicates, as in the case of the European cuckoo, the visits of two cow-birds rather than a second visit from the same individual—the presence of two cow-bird chicks of equal size being rather a proof of this than otherwise, in that kind Nature would seem to have accommodated the bird with an exceptional physiological resource, which matures its eggs at intervals of three or more days, as against the daily oviposition of its dupes, thus giving it plenty of time to make its search and take its pick among the bird-homes. Whether the process of evolution has similarly equipped our cow-bird I am not aware; but the vicious habits of the two birds are so identical that the same accommodating functional conditions might reasonably be expected. It is, indeed, an interesting fact well known to ornithologists that our own American cuckoos, both the yellow-billed and black-billed, although rudimentary nest-builders, still retain the same exceptional interval in their egg-laying as do their foreign namesake. The eggs are laid from four days to a week apart, instead of daily, as with most birds, their period of perilous nidification on that haphazard apology of a nest being thus possibly prolonged to six weeks. Thus we find, in consequence, the anomalous spectacle of the egg and full-grown chick, and perhaps one or two fledglings of intermediate stages of growth, scattered about at once, helter-skelter, in the same nest. Only two years ago I discovered such a nest not a hundred feet from my house, containing one chick about two days old, another almost full-fledged, while a fresh-broken egg lay upon the ground beneath. Such a household condition would seem rather demoralizing to the cares of incubation, and doubtless the addled or ousted egg is a frequent episode in our cuckoo's experience.

It is an interesting question which the contrast of the American and European cuckoo thus presents. Is the American species a degenerate or a progressive nest-builder? Has she advanced in process of evolution from a parasitical progenitor building no nest, or is the bird gradually retrograding to the evil ways of her notorious namesake?

The evidence of this generic physiological peculiarity in the intervals of oviposition, taken in consideration with the fact of the rudimentary nest, would seem to indicate the retention of a now useless physiological function, and that the bird is thus a reformer who has repudiated the example of her ancestors, and has henceforth determined to look after her own babes.

With the original presumed object of this remarkable prolonged interval in egg-laying now removed, the period will doubtless be reduced through gradual evolution to accommodate itself to the newly adopted conditions. The week's interval, taken in connection with the makeshift nest or platform of sticks, is now a disastrous element in the life of the bird. Such of the cuckoos, therefore, as build the more perfect nests, or lay at shortest intervals, will have a distinct advantage over their less provident fellows, and the law of heredity will thus insure the continual survival of the fittest.

The cuckoo is not alone among British birds in its intrusion on other nests. Many other species are occasionally addicted to the same practice, though such acts are apparently accidental rather than deliberate, so far as parasitical intent is concerned. The lapse is especially noticeable among such birds as build in hollow trees and boxes, as the woodpeckers and wagtails. Thus the English starling will occasionally impose upon and dispossess the green woodpecker. In the process of nature in such cases the stronger of the two birds would retain the nest, and thus assume the duties of foster-parent. Starting from this reasonable premise concerning the prehistoric cuckoo, it is not difficult to see how natural selection, working through ages of evolution by heredity, might have developed the habitual resignation of the evicted bird, perhaps to the ultimate entire abandonment of the function of incubation. Inasmuch as "we have no experience in the creation of worlds," we can only presume.

Indeed, the similarities and contrasts afforded by a comparison of the habits of all these birds—European cuckoo, American cuckoo, and cow-bird—afford an interesting theme for the student of evolution. What is to be the ultimate outcome of it all? for the murderous cuckoo must be considered merely as an innocent factor in the great scheme of Nature's equilibrium, in which the devourer and the parasite would seem to play the all-important parts, the present example being especially emphasized because of its conspicuousness and its violence to purely human sentiment. The parasite would often seem to hold the balance of power.

The Yellow Warbler

Jonathan Swift's epitome of the subject, if not specifically true, is at least correct in its general application:

Even the tiny egg of a butterfly has its ichneumon parasite, a microscopic wasp, which lays its own egg within the larger one, which ultimately hatches a wasp instead of the baby caterpillar.

But who ever heard of anything but good luck falling to the lot of cow-bird or cuckoo, except as its blighting course is occasionally arrested by the outraged human? They always find a feathered nest.

In this connection it is interesting to note certain developments in bird life upon the lines of which evolution might work with revolutionary effect. Most of our birds are helpless and generally resigned victims to the cow-bird, but there are indications of occasional effective protest among them. Thus the little Maryland yellow-throat, according to various authorities, often ousts the intruded egg, and its broken remains are also occasionally seen on the ground beneath the nests of the cat-bird and the oriole. The red-eyed vireo, on the other hand, though having apparently an easier task than the latter, in the lesser depth of her pensile nest, commonly abandons it altogether to the unwelcome speckled ovum—always, I believe, if the cow-bird has anticipated her own first egg.

A Blighted Home

But we have a more remarkable example of opposition in the resource of the little yellow warbler, which I have noted as one of the favorite dupes of the cow-bird—a deliberate, intelligent, courageous defiance and frequent victory which are unique in bird history, and which, if through evolutionary process they became the fashion in featherdom, would put the cow-bird's mischief greatly at a discount. The identity of this pretty little warbler is certainly familiar to most observant country dwellers, even if unknown by name, though its golden-yellow plumage faintly streaked with dusky brown upon the breast would naturally suggest its popular title of "summer yellow-bird." It is one of the commonest of the mnio-tiltidæ, or wood-warblers, though more properly a bird of the copse and shrubbery than of the woods.

The Normal Nest of the Yellow Warbler

This nest is a beautiful piece of bird architecture. In a walk in search of one only a day or two ago I procured one, which is now before me. It was built in the fork of an elder-bush, to which it was moored by strips of fine bark and cobweb, its downy bulk being composed by a fitted mass of fine grass, willow cotton, fern wood, and other similar ingredients. It is about three inches in depth, outside measurement. But this depth greatly varies in different specimens. Our next specimen may afford quite a contrast, for the yellow warbler occasionally finds it to her interest to extend the elevation of her dwelling to a remarkable height. On page 50 is shown one of these nests, snugly moored in the fork of a scrub apple-tree. Its depth from the rim to the base, viewed from the outside, is about five inches, at least two inches longer than necessity would seem to require, and apparently with a great waste of material in the lower portion, as the hollow with the pretty spotted eggs is of only the ordinary depth of about two inches, thus hardly reaching half-way to the base. Let us examine it closely. There certainly is a suspicious line or division across its upper portion, about an inch below the rim, and extending more or less distinctly completely around the nest. By a very little persuasion with our finger-tip the division readily yields, and we discover the summit of the nest to be a mere rim—a top story, as it were—with a full-sized nest beneath it as a foundation. Has our warbler, then, come back to his last year's home and fitted it up anew for this summer's brood? Such would be a natural supposition, did we not see that the foundation is as fresh in material as the summit. Perhaps, then, the bird has already raised her first spring brood, and has simply extended her May domicile, and provided a new nursery for a second family. But either supposition is quickly dispelled as we further examine the nest; for in separating the upper compartment we have just caught a glimpse of what was, perhaps only yesterday, the hollow of a perfect nest; and, what is more to the point of my story, the hollow contains an egg—perhaps two, in which case they will be very dissimilar, one of delicate white with faint spots of brown on its larger end, the putting of the warbler, the other much larger, with its greenish surface entirely speckled with brown, and which, if we have had any experience in bird-nesting, we immediately recognize as the mischievous token of the cow-bird. We have discovered a most interesting curiosity for our natural-history cabinet—the embodiment of a presumably new form of intelligence in the divine plan looking to the survival of the fittest. It is not known how many years or centuries it has taken the little warbler to develop this clever resource to outwit the cow-bird. It is certain, however, that the little mother has got tired of being thus imposed upon, and is the first of her kind on record which has taken these peculiar measures for rising above her besetting trouble.

The Yellow Warbler at Home

A Suspicious Nest of the Yellow Warbler

Who can tell what the future may develop in the nests of other birds whose homes are similarly invaded? I doubt not that this crying cow-bird and cuckoo evil comes up as a matter of consideration in bird councils. The two-storied nest may yet become the fashion in featherdom, in which case the cow-bird and European cuckoo would be forced to build nests of their own or perish.

But have we fully examined this nest of our yellow warbler? Even now the lower section seems more bulky than the normal nest should be. Can we not trace still another faint outline of a transverse division in the fabric, about an inch below the one already separated? Yes; it parts easily with a little disentangling of the fibres, and another spotted egg is seen within. A three-storied nest! A nest full of stories—certainly. I recently read of a specimen containing four stories, upon the top of which downy pile the little warbler sat like Patience on a monument, presumably smiling at the discomfiture of the outwitted cow-bird parasite, who had thus exhausted her powers of mischief for the season, and doubtless convinced herself of the folly of "putting all her eggs in one basket."

The Nest Separated

When we consider the life of the cow-bird, how suggestive is this spectacle which we may see every year in September in the chuckling flocks massing for their migration, occasionally fairly blackening the trees as with a mildew, each one the visible witness of a double or quadruple cold-blooded murder, each the grim substitute for a whole annihilated singing family of song-sparrow, warbler, or thrush! What a blessing, at least humanly speaking, could the epicurean population en route in the annual Southern passage of this dark throng only learn what a surpassing substitute they would prove—on toast—for the bobolinks which as "reed-birds" are sacrificed by the thousands to the delectable satisfaction of those "fine-mouthed and daintie wantons who set such store by their tooth"!

And what the cow-bird is, so is the Continental "cuckoo." Shall we not discriminate in our employment of the superlative? What of the throstle and the lark? Shall we still sing—all together: