My Studio Neighbors. Gibson William Hamilton

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      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, СКАЧАТЬ