Page:Popular Science Monthly Volume 2.djvu/526

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508
THE POPULAR SCIENCE MONTHLY.
 

The English Sparrow.—In a paper lately read before the Long Island Historical Society, by Mr. E. Lewis, Jr., and since published in the Brooklyn Union, we find the following interesting particulars concerning the importation into this country of the English sparrow, and the valuable service it has since rendered in clearing our city trees of insect-pests. As many are aware, the trees of Brooklyn some years ago were overrun by a species of caterpillar (Ennomos subsignaria), which, commencing when the leaves were young and tender, devoured them so rapidly that in a short time the branches were completely bared, making the tree an unsightly object, and greatly injuring its health and growth. The creatures also had the disgusting habit of suspending themselves from the limbs, whence they would drop in great numbers both upon the pavements and passing pedestrians. The maple, horse-chestnut, elm, and willow, were-thus attacked, and their destruction, or that of the caterpillars, was the alternative presented to the Brooklyn people. All sorts of expedients were proposed, and among them the introduction of the English sparrow. In spite of the failure of a previous attempt, a second was decided on, and in the fall of 1856 Mr. Thomas Woodcock, of Brooklyn, at the instance of the Brooklyn Institute, brought over from Manchester about a dozen sparrows, which were liberated in the following spring, when they flew away toward Brooklyn Heights. Nothing more was heard of them until the spring of 1858, when two pair were observed among the ivies of Grace Church, where it is probable that one or more nests were built, as during the summer young sparrows were noticed in the vicinity. Since that time their increase has been enormous, and almost solely through their agency the caterpillar nuisance has been completely removed.

According to Mr. Lewis, though feeding largely on seeds, and in cities upon almost every article of human food, the sparrows feed their young chiefly with worms, larvæ, the soft portions of coleoptera, moths, and other tender animal food. "By this means the number of devouring worms has been greatly diminished. The leaf-rolling caterpillar of the sycamore and the currant-bush are known to be taken and devoured by sparrows.

The inch-worm, too, is taken when young, as is the Japanese silk-worm, which feeds upon the ailantus-leaf.

"But the sparrows destroy the caterpillar family in a more effectual way than this. The large female moths of the Samia cynthia, or Japanese silk-worm, are seized for the eggs which they contain, torn to pieces, and the eggs devoured. So persistent are the sparrows in watching for and catching these moths, that a gentlemen in this city has been unable to raise either worms or moths unless protected from the birds.

"The moths, both male and female, of the inch-worm or tree-caterpillar, are eaten by sparrows. After seizing the moth, they will beat off its head and wings and feed to their young the soft parts of the insect.

"The destruction of the female moths arrests the increase of the caterpillars in a most effective way. But this is not all. We have referred to the sparrows feeding upon the eggs of moths after being deposited upon branches of trees. I have watched them at this frequently during the winter. These eggs are usually deposited in places where they are sheltered by raised or fractured fragments of the old bark, and are covered with a glutinous substance. The sparrow labors until fairly weary in breaking away the old bark and laying bare the eggs, which it removes with some difficulty, but which it nevertheless removes and devours.

"It is thus apparent that the chance for a full crop of caterpillars is small where sparrows are abundant. Indeed, the disgusting tree-caterpillar has disappeared from our city altogether."

The Brooklyn Institute has also attempted the introduction of English song-birds, but as yet with indifferent success. Among those brought over are the skylark, wood-lark, goldfinch, robin, and thrush. Some are known to have survived and produced young; but the general impression is that our winters are too severe for them to do well in this climate. "The sparrows," says Mr. Lewis, "seem to be well acclimated, although many have been found dead, after severe frosts and snow. It is evident that the severity of the climate, or some other cause, has somewhat arrested their growth, as persons, who are competent to