Thoreau writes in his journal:
The fall, now and for some weeks, is the time for flocks of sparrows of various kinds flitting from bush to bush and tree to tree—and both bushes and trees are thinly leaved or bare—and from one seared meadow to another . . .
I have often noticed the inquisitiveness of birds, as the other day of a sparrow, whose motions I should not have supposed to have any reference to me, if I had not watched it from first to last. I stood on the edge of a pine and birch wood. It flitted from seven or eight rods distant to a pine within a rod of me, where it hopped about stealthily and chirped awhile . . . I could see nothing peculiar about it. But when I brought my glass to bear on it, I found that it was almost steadily eying me and was all alive with excitement . . .