After spending the day in detached groups, they gather late in the afternoon, and prepare for the flight to the roosting-grounds, which is an affair of the utmost importance and ceremony. A single scout will come ahead, and after slowly and carefully inspecting the area in the forest where the night is usually spent, he returns in the direction from which he came.
In a few minutes several crows come over the same course and apparently verify the conditions. These also return, and a little later, perhaps twenty or thirty more will appear and fly all over the territory under consideration. They go and report to the main body beyond the hills, and soon the horizon becomes black with the oncoming phalanxes, steadily winging their way to the chosen spot.
For a long time the sky above it is filled with their dark forms, circling and hovering over and among the trees. Much uncertainty seems to agitate them, and there is a great deal of noisy confusion before even comparative quiet comes. It requires about half an hour for them to get comfortably settled after their arrival. Sentinels are posted and they maintain a vigilant watch during the night.
I have sat quietly on a log and seen these multitudes settle into the trees around me in the deep woods. Although perfectly motionless, I have sometimes been detected by a watchful sentinel. His quick, loud note of alarm arouses the entire aggregation, and the air is immediately filled with the turmoil of discordant cries and beating wings. Sacred precincts have been invaded, and an enemy is within the gates.
After much anxiety, and shifting of positions, confidence seems to be finally restored, and the black masses on the bending boughs become quiet.
A footfall on the dead leaves, the snapping of a twig, a suspicious movement among the trees, or the hoot of an owl, may alarm the wary watchers and start another uproar that will result in complete desertion of the vicinity of the suspected danger.
When morning comes, various groups visit the beach and strut along the shore, drinking and picking up stray morsels. Dead fish that have been cast in by the waves, and numerous insects crawling on the sand, are eagerly devoured. Usually before sunrise the crows have started out over the country in detached flocks.