Called also: MARSH HARRIER; BLUE HAWK; MOUSE HAWK
LengthMale 19 inches; female 22 inches.
MaleUpper parts gray or bluish ash, washed with brownish; upper tail coverts pure white; silver gray tail feathers with five or six dusky bars, the outer primaries darkest; upper breast pearl gray, shading into white underneath, where the plumage is sparsely spotted with rufous. Hooked bill, and feet black.
Female and YoungUpper parts dark amber; the head and neck streaked, other parts margined or spotted with reddish brown; upper tail coverts white; middle tail feathers barred with gray and black, others barred with pale yellow and black. Under parts rusty buff, widely streaked on breast and more narrowly underneath with dusky. The younger the bird the heavier its blackish and rufous coloration, many phases of plumage being shown before emerging into the gray and white adult males.
RangeNorth America in general, to Panama and Cuba; nests throughout North American range; winters in southern half of it.
SeasonSummer resident at northern half of range.
Close along the ground skims the marsh hawk, since field mice and other small mammals, frogs, and the larger insects that hide among the grass are what it is ever seeking as it swerves this way and that, turns, goes over its course, ” quartering ” the ground like a well trained dog on the scent of a harethe peculiarity of flight that has earned it the hare-hound or harrier’s name. A few easy strokes in succession, then a graceful sail on motionless wings, make its flight appear leisurely, even slow and spiritless, as compared with the impetuous dash of a hawk that pursues feathered game; hence this is counted an ” ignoble ” hawk in the scornful eyes of falconers used to the noble sport of hawking. Open stretches of country, wide fields, salt and fresh water marshes, ponds, and the banks of small streams, whose sides are not thickly wooded, since trees simply impede this low flier’s progress, are its favorite hunting grounds; and it will sometimes alight on a low stump, or in the grass itself, for it is a low percher too. Because its quarry is humble, and farmers, on the whole, appreciate its service in destroying meadow mice, crickets, grasshoppers, and other pests, this bird suffers comparatively little persecution, and still remains one of the most widely distributed and common of its tribe. That it occasionally preys upon small birds, when other food fails, cannot be denied; but nearly one-half of all the stomachs examined by Mr. Fisher, for the Department of Agriculture, contained mice.
In the nesting season especially, the harrier belies that name, but, proving his title to Circus, his Latin one, wheels round and round and floats high above the earth, describing some beautiful evolutions as he goes, that are calculated simply to stimulate afresh the ardor of his well beloved, since evidence strongly points to a life partnership between the mates. Soaring in the sky, suddenly he falls, turning several somersaults in the descent. “At other times,” says Mr. Ernest Seton Thompson, “he flies across the marsh in a course which would outline a gigantic saw, each of the descending parts being done in a somersault, and accompanied by screeching notes which form the only love song within the range of his limited powers.” All hawks have a screaming, harsh cry, not distinctly different in the different species to serve as a clew to identity except to those well up in field practice; but the white lower back of the harrier, its long tail, and its terrestrial habits serve to identify it in any phase of plumage. Owing to its long wings, it appears much larger in the air than on the ground. Four to six dull or bluish white eggs, unmarked, are laid in May, in a nest built of twigs, hay, and weeds, on the ground; yet the clumsy affair was the joint effort of the mates, that also take turns in sitting and in feeding the young.