“Last but not least, in their young days when, weak and featherless, they are fed from the parents’ beak, many granivorous birds are brought up on insects. The reason is plain enough. You can readily understand that the delicate crop of a young bird just out of the shell has not the strength to digest hard, dry seeds. It must have something more nourishing, something smaller and, above all, [[258]]more succulent, such as a marmalade of grubs prepared in the mother’s beak. A few days later, with the first growth of down, will come little soft caterpillars served whole; then tougher insects will prepare the stomach for the more difficult digestion of seeds. I select a few examples at random.
“The chaffinch, the gay chaffinch, is well known to be a granivorous bird, a lover of millet and hemp-seed. Now, what does it give its little ones while they are still in the nest? It gives them hairless caterpillars and tender larvæ, chosen as being the easiest food to digest. I can say the same of the greenfinch, a bird with plumage midway between green and yellow; of the bullfinch, known by its red breast and stomach; and of the various buntings that come in the winter in flocks, pecking around our straw-stacks. These last, however, feed perhaps more than the others on seeds, as they have on the inside of the upper mandible a small, hard excrescence intended expressly for crushing them.
“I might add to these examples, but prefer to conclude with a bird that is one of the most familiar to you, the sparrow. Here, certainly, we have an undoubted seed-eater. It raids our dove-cotes and poultry-yards and steals the food of our pigeons and poultry. It goes a-harvesting in the grain-fields before our reapers have begun their task. A great many other misdeeds are laid at its door. It strips cherry-trees, plunders our gardens, forages for sprouting seeds, regales itself on young lettuce, and nips the first little leaflets of green peas. But when [[259]]hatching-time comes this bold pilferer is transformed into a helper inferior to none. At least twenty times an hour the father and the mother, by turns, bring a mouthful to their young ones, and each time it consists of either a caterpillar or an insect large enough to require quartering, or perhaps a larva as fat as butter; or it may be a grasshopper or some other small game. In one week the brood consumes about three thousand insects, including larvæ, caterpillars, and grubs of all kinds. I have counted in the immediate vicinity of a single nest of these birds the remains of seven hundred June-bugs besides small insects without number. Behold what a store of food is needed for raising only one brood! What quantities of vermin, then, must all the broods of a community devour! After such services let him who will presume to raise a hand against our sparrows; as for me, I leave them in peace as long as they do not become too troublesome.
European House Sparrow
“My closing word is this: eaters of seeds and eaters of insects, grosbeaks and slender-beaks, some in greater degree, some in less, all come to our aid. Peace, then, to the little birds, the joy of the country-side and the protectors of our crops!” [[260]]
CHAPTER XXXIV
SNAKES AND LIZARDS
“I propose to-day to undertake the defense of reptiles, which many people fear and dislike, even look upon with horror. I have shown you what services are rendered by bats despite the repugnance we feel for them. These animals, regarded by us as hideous and treated as enemies, I have brought you to look upon as valuable helpers, veritable swallows of the night, devoted to the extermination of twilight insects. As soon as reason illuminates the darkness of prejudice the detested creature is found to be a very useful animal. In like manner I shall now try to make you separate the false from the true in respect to the reptiles. Let us begin with the snake.