A flock of thousands of barn swallows.

August 4.

August 4, 2015

Just after bathing at the rock near the Island this afternoon, after sunset, I saw a flock of thousands of barn swallows and some white-bellied, and perhaps others, for it was too dark to distinguish them. 

They came flying over the river in loose array, wheeled and flew round in a great circle over the bay there, about eighty feet high, with a loud twittering as if seeking a resting-place, then flew up the stream. I was very much surprised at their numbers.

Directly after, hearing a buzzing sound, we found them all alighted on the dense golden willow hedge at Shattuck’s shore, parallel with the shore, quite densely leaved and eighteen feet high. They were generally perched five or six feet from the top, amid the thick leaves, filling it for eight or ten rods. 

They were very restless, fluttering from one perch to another and about one another, and kept up a loud and remarkable buzzing or squeaking, breathing or hum, with only occasionally a regular twitter, now and then flitting along side from one end of the row to the other. It was so dark we had to draw close to see them. At intervals they were perfectly still for a moment, as if at a signal. 

At length, after twenty or thirty minutes of bustle and hum, they all settled quietly to rest on their perches, I supposed for the night. We had rowed up within a rod of one end of the row, looking up so as to bring the birds between us and the sky, but they paid not the slightest attention to us. 

What was remarkable was: first, their numbers; second, their perching on densely leaved willows; third, their buzzing or humming, like a hive of bees, even squeaking notes; and fourth, their disregarding our nearness. I supposed that they were preparing to migrate, being the early broods.

H. D. Thoreau, Journal, August 4, 1855

Disregarding our nearness... See July 12, 1854 ("Many young barn swallows sit in flocks on the bared dead willows over the water and let me float within four or five feet. Birds do not distinguish a man sitting in a boat.")

I supposed that they were preparing to migrate, being the early broods. See August 5, 1855 ("On river to see swallows. They are all gone. . . Probably they started very early. I asked Minott if he ever saw swallows migrating,. . . He thought it was in the latter part of August."); August 29,1854 (". . .the barn swallows are very lively, filling the air with their twittering now, at 6 p.m. They rest on the dry mullein-tops, then suddenly all start off together as with one impulse and skim about over the river, hill, and meadow. . . .Are they not gathering for their migration?")