The various crows of the world are like small ravens--jet-black, sometimes marked with white; but our familiar American crow is wholly black. These birds are fond of gathering into flocks, which sometimes are very large; and they are sociable, liking to spend the night roosting in some favorite grove in great companies. When near the sea, or some large river or lake, the crows go down to the shore every morning, and spend most of the day on or near the beach, where they pick up most of their food. Crows, however, will eat almost anything edible except grain; and the great European carrion-crow is almost a bird of prey, for like the raven it feeds chiefly on the flesh of dead animals. But it also preys upon such creatures as rabbits, hares, mice, frogs, and lizards, while it will also search for the nests of game birds and poultry, and carry off the eggs and the young. Sometimes, too, it will visit the seashore, and feast upon the crabs, limpets, and mussels which it finds among the rocks at low water. In order to crack the shells of these creatures, it is said sometimes to carry them up into the air and drop them upon a rock.
Except that it places its rude, stick-built nest in scattered trees, each pair by itself, instead of in a company, our American crow is closely similar to the English rooks about which so much is said in books about Great Britain. Everybody in England knows the rook by sight, and everybody is familiar with the rookeries in which a number of these birds nest together year after year. Indeed, they use the same nests over and over again, just putting them into proper order shortly before the eggs are laid.
The scene when building operations begin is always a lively one, and all day long the birds are very busy. But oddly enough, they never seem to know when the winter is really over, and when a thaw comes after two or three frosty days in December, or even earlier, they get as excited as possible, setting to work and gathering sticks, and evidently thinking that spring is beginning!
Rooks have very strict rules when they are building. For one rook to steal a stick from another rook's nest, for example, is a very serious crime, and sometimes is punished even with death. And young birds are not allowed to build in a tree outside the rookery, their nest being at once pulled to pieces by the older ones if they attempt to do so.