282 MICHIGAN BIRD LIFE. 
Park, Wayne county, April 29, 1893. The nest was 55 feet up in a beech 
tree. Mr. Swales also states that this species is fairly abundant in St. Clair 
county and is known to breed. 
In its general habits it somewhat resembles the other Buteos but its 
food consists more largely of insects and it is entirely free from suspicion 
of injury to the farmer. It eats mice, squirrels, ground squirrels, rats, 
shrews, wood mice, as well as grasshoppers, crickets, beetles, and the large, 
green, naked caterpillars which are the larve of destructive moths. Out of 
38 stomachs reported on by Dr. Fisher, 2 contained small birds; 15, mice; 
13, other mammals; 11, reptiles; 13, batrachians; 30, insects; 2, earthworms; 
and 4, crayfish. 
The Broadwing nests always in trees, the nest being made ordinarily of 
sticks and lined with thin scales of dry bark, but not infrequently green 
leaves are added, possibly for protection during the absence of the parents. 
The eggs are commonly two or three, very rarely four, the ground color 
grayish white, spotted in variable degrees with brown or gray. They 
average 1.93 by 1.56 inches. 
This is another of our hawks which often migrates in flocks, and sometimes 
hundreds may be seen passing slowly northward in spring, or southward 
in fall, now flapping steadily, and again circling and drifting slowly 
in the desired direction. The autumn migration takes place mostly between 
the middle of September and the 10th of Otcober, and the birds return 
from the south early in April. 
TECHNICAL DESCRIPTION. 
Only three outer primaries notched (emarginate) on the inner webs; wing never more 
than 13.50 inches long. 
Adult: Upper parts grayish brown to brownish black, darkest on interscapulars and 
crown, often with distinct purplish reflections; forehead and chin whitish, the latter some- 
times streaked with dusky, sometimes pure white; feathers of occiput pure white below 
the surface; underparts reddish brown, everywhere spotted or barred with white, most 
freely and regularly on the belly, flanks and thighs (tibie), least on the chest; sides of 
neck without white, but usually with a blackish patch from corner of mouth backward; 
tail brownish black to clear black above, with 2 to 4 distinct, wide cross-bars of white or 
grayish, and a narrow tip of the same shade; iris, cere and feet yellow. Immature: Upper 
parts almost precisely like those of the young Red-shouldered Hawk, but the shoulders 
not rusty, nor the outer webs of the primaries light-spotted; under parts pure white to 
buffy white, more or less heavily spotted and streaked with dark brown, but without bars 
except imperfect ones on flanks and thighs; chin and throat usually pure white, with few 
or no streaks; iris bright yellow; cere and feet greenish yellow. 
Male: Length, 13.25 to 15 inches; wing, 9.85 to 10.70; tail, 6.50 to 7. Female: Length, 
16 to 18 inches; wing, 11 to 11.40; tail, 7 to 8. 
142. Rough-legged Hawk. Archibuteo lagopus sancti-johannis (Gmel.). 
(347a) 
Synonyms: American Rough-legged Hawk, Rough-legged Buzzard, Black Hawk, 
Mouse Hawk.—Falco sancti-johannis, Gmel., 1788.—Buteo sancti-johannis, Nutt., 1833. 
—Falco lagopus, Wils., 1808.—Buteo lagopus, Rich., 1831. 
Known from all the rest of our hawks by the feathered shank or tarsus, 
only the toes being naked. It is about the size of the Red-tailed Hawk, but 
a much lighter built bird, with more slender feet, weaker bill, and especially 
longer, more pointed wings. Its plumage is too variable for ready descrip- 
tion, but nearly black individuals are rather common, and in specimens 
not so colored a broad dark zone across the lower breast and belly is usual. 
