282 MICHIGAN BIRD LIFE. 



Piii'k, Wayne county, April 29, 1893. The nest was 55 feet up in a })eech 

 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 larvse 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 pur])Hsh reflections; forehead and ciiin whitish, the latter some- 

 times streaked with (hisky, sonu'times pure white; featliers of occiput pure white below 

 the surface; imderparts redtlish l)rown, everywhere spotted or barred with white, most 

 freely and regularly on the belly, flanks and thighs (tibise), 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 (GmcL). 



(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 coloi'cd a broad dark zone across the lower breast and belly is usual. 



