119 
BIRDS OF PENNSYLVANIA. 
\ 
Genus CIRCUS Lacepede. 
Circus hudsonius (Linn.). 
Marsh Hawk ; Harrier ; Bog-trotter. 
Description {Plate 18). 
Face partly encircled by a ruff or imperfect facial disc of small stiffened feathers, 
as in the owls ; nostrils large ; wings long and pointed ; tail long ; tarsus long and 
slender. 
Male.—lA^hi bluish-gray above and on neck and breast; upper tail-coverts and 
most of under parts white ; some under feathers under wings and lower part of 
breast and abdomen spotted with rusty. Female and young are dark-brown above, 
streaked on head and • neck with reddish-brown ; below reddish-brown, much 
brighter in some specimens than others ; upper tail coverts white. Length of female 
about 18 to 20 inches ; extent about 44 ; tail 9 or 10 inches ; bill and claws blackish ; 
legs, feet and eyes yellow. 
Habitat. — North America in gelieral, south to Panama. 
The Marsh Hawk is most frequently seen throug’hout Pennsylvania 
in the spring- and fall, but it breeds often in different parts of the state, 
and in some of the southern counties it is found during- all months of 
the year. Its nests, with eg-g-s or young-, have been found by the fol- 
lowing gentlemen in their respective counties. Dr. John W. Detwiller, 
Northampton; R. C. Wrenshall, Allegheny; H. J. Roddy, Perry; Dr. 
Yan Fleet, Clinton; Geo. S. Morris, Philadelphia; Hon. G. S. Brown, 
York; Otto Belli-, Sullivan; W. W. Stoey, Dauphin, and J. L. Camp, 
Bradford. I have observed the Marsh Hawk to be most numerous in 
the fall, frequenting the extensive and grassy meadow-lands, chiefly 
about the large streams. 
When flying this species can easily be distinguished from other 
hawks by the white upper tail-coverts, so conspicuous in the females 
and immature birds, or those usually met with. The old male, rare and 
seldom found in this section, can be recognized by the bluish-white 
plumage. 
The nest of the Marsh Hawk differs from that of all others of the 
family which breed here, in being placed on the ground, and usually, it 
is said, in a swamp or meadow. The nest, according to different 
writers, is composed of sticks, grasses, hay, etc., or sometimes no nest 
is made, the eggs simply being deposited on a bed of grass, moss, etc., 
on the ground. “ Eggs, three to eight, 1.80 by 1.41, white or bluish- 
white, usually plain, but often more or less spotted or blotched with 
pale hvown.”—Ridgioay. 
Notwithstanding the fact that these hawks rarely, if ever, prey upon 
any kind of game except sometimes an occasional Reed bird, gunners, 
who so industriously search over the swamps, never fail to destroy every 
Marsh Hawk which comes within range of their deadly weapons. 
Marsh Hawks never, to my knowledge, disturb poultry, but subsist 
