The Chipping Sparrow has very slight claims to be regarded as one of our song-birds. Its note of complaint or uneasiness is a simple _chip_, and its song, at its best, is but a monotonous repetition of a single note, sounding like the rapid striking together of two small pebbles. In the bright days of June this unpretending ditty is kept up incessantly, hours at a time, with only rare intermissions.
The nest of this bird is always in trees or bushes. I have in no instance known of its being built on the ground. Even at the Arctic regions, where so many of our tree-builders vary from this custom to nest on the ground, no exceptional cases are reported in regard to it, all its nests being upon trees or in bushes. These are somewhat rudely built, often so loosely that they may readily be seen through. Externally they are made of coarse stems of grasses and vegetable branches, and lined with the hair of the larger animals.
These birds are devoted parents, and express great solicitude whenever their nests are approached or meddled with. They feed their young almost exclusively with the larvæ of insects, especially with young caterpillars. When in neighborhoods infested with the destructive canker-worm, they will feed their young with this pest in incredible numbers, and seek them from a considerable distance. Living in a district exempt from this scourge, yet but shortly removed from them, in the summer of 1869, I noticed one of these Sparrows with its mouth filled with something which inconvenienced it to carry. It alighted on the gravel walk to adjust its load, and passed on to its nest, leaving two canker-worms behind it, which, if not thus detected, would have introduced this nuisance into an orchard that had previously escaped, showing that though friends to those afflicted they are dangerous to their neighbors. This Sparrow is also the frequent nurse of the Cow Blackbird, rearing its young to the destruction of its own, and tending them with exemplary fidelity.
Their eggs, five in number, are of an oblong-oval shape, and vary greatly in size. They are of a bluish-green color, and are sparingly spotted about the larger end with markings of umber, purple, and dark blackish-brown, intermingled with lighter shadings of faint purple. The largest specimen I have ever noticed of this egg, found in the Capitol Grounds, Washington, measures .80 by .58 of an inch; and the smallest, from Varrell’s Station, Ga., measures .60 by .50. Their average measurement is about .70 by .54. They are all much pointed at the smaller end.