Outside of half a dozen of the very commonest they were strangers to him.

The likeness of their actions to humanity was an hourly surprise.
When black frost began stripping the Limberlost, cutting the ferns, shearing the vines from the trees, mowing the succulent green things of the swale, and setting the leaves swirling down, he watched the departing troops of his friends with dismay.

He began to realize that he would be left alone.

He made especial efforts toward friendliness with the hope that he could induce some of them to stay.

It was then that he conceived the idea of carrying food to the birds; for he saw that they were leaving for lack of it; but he could not stop them.