The goshawk and chicken-hawk, in the amount of damage done, far exceed all other birds of prey. The sharp-shinned hawk rarely attacks full-grown poultry, but preys heavily on young chickens and song birds. In fact, it is known to eat nearly fifty species of our most useful birds. There is no question that these birds are a serious pest and should be destroyed, but they should not be confused with other members of the family which are among the best friends that a farmer has in keeping his farm clear of small enemies.
Owls and hawks eat the same class of food, the hawks flying by day and the owls by night. Owls remain North in winter, while hawks fly farther south.
The small species of both eat large quantities of insects, such as grasshoppers, locusts and beetles. The larger ones are the farmer's great protection against the meadow-mouse, the most destructive of all animals to farm crops. It tunnels under fields and eats the roots of grass, grain and potatoes, eats large amounts of grain and does even more damage by girdling young trees in orchards. Rabbits injure trees in the same way, often during the winter ruining an entire orchard in this manner.
Squirrels, ground-squirrels, gophers, prairie-dogs, and other small animals do serious damage in the course of a year on almost every farm.
The rough-leg hawk feeds entirely on meadow-mice, but if the supply fails, it eats mice, rabbits and ground-squirrels, but in no instance attacks birds. Its cousin, the ferruginous rough-leg, lives largely on ground-squirrels, rabbits, prairie-dogs and pouched gophers. This species also never attacks birds, and neither do any of the four members of the kite family.
Another large class of birds,—the marsh-hawk, Harris hawk, red-tailed hawk, red-shouldered hawk, short-tailed hawk, white-tailed hawk, Swainson hawk, short-winged hawk, broad-winged hawk, Mexican black hawk, Mexican goshawk, sparrow-hawk, barn-owl, long-eared owl, short-eared owl, great gray owl, barred owl, western owl, Richardson owl, screech-owl, snowy owl, hawk-owl, burrowing owl, pigmy owl and elf owl—live mostly on destructive mammals, insects, frogs and snakes, but they eat some birds and some of them occasionally catch poultry. Young ones do much more harm than the full-grown ones, probably because they find poultry and birds easier to obtain than other food. These species all do great good on the farm and in the orchard and if their natural food is plentiful and the number of the birds of prey limited, they should be allowed to remain, even though they occasionally do harm; but they can not be allowed to increase greatly in a region without becoming a nuisance.
In another class the golden and bald eagles, pigeon and Richardson hawks, prairie falcon and great horned owl do considerable harm, and the good and bad qualities about balance. In a poorly settled region, where there is plenty of natural food, a few of these birds will bring forth little complaint, but in a section where there are few ground-squirrels, prairie-dogs, gophers, rabbits and woodchucks, where poultry is raised extensively, and useful birds are numerous they will do great harm and farmers will usually want to keep them down entirely.
The gyrfalcons, duck-hawks, sharp-shinned hawk, Cooper hawk and goshawk live almost entirely on food that is desired by man,—poultry, game birds and many varieties of our best insect-destroying birds, and they eat almost nothing that is harmful to man. The numbers of these birds should be reduced as much as possible: but in general it may be said that the birds of prey—the hawks and owls—are among the most, if not the most, valuable birds that are engaged in helping the farmer by destroying the natural enemies of agriculture.
Among the smaller birds which do much good, but of which complaints are made because they eat some fruit and grain are the woodpeckers, including the flickers, cedar-birds, robins, cat-birds, thrashers, crows and blackbirds.
The woodpeckers are the great natural protection of the forests by waging constant warfare on the wood-boring insects and ants beneath the bark where no other birds can reach them. They are equally useful in an orchard except that here man may only at great trouble and expense partly hold them in check. Downy woodpeckers are also great eaters of scales, and the fruit grower need not begrudge the red-headed woodpecker a meal of cherries or apples, especially as it will usually be found that it is the wormy fruit that is attacked.