SUPPLEMENT TO BIRDS OF ESSEX COUNTY 103 



Buteo. I could distinctly see the shape of its bill and a shade of chestnut-brown 

 on the flanks. After talking with Mr. Brewster and examining his specimens I 

 have little doubt but that this was a Swainson's Hawk. 



152 [343] Buteo platypterus (Vieill.). 



Broad-winged Hawk. 



Not uncommon transient visitor, very rare summer resident. May 3 to May 

 21 ; July; September 11 to November 30. 



This is one of the easiest hawks to study as it generally allows of close 

 approach. Its characteristic Buteo shape, — short tail and broad wings, whose 

 tips reach nearly to the end of the tail when the bird is on a perch, — and its small 

 size, about that of a Crow, make its recognition in the field easy. On careful 

 scrutiny one can often see a light buff line over the eye, the brown markings on 

 the side, the hufi middle breast and belly, and the yellow cere and tarsi. Its 

 characteristic cry, which it frequently emits, also helps identify it. This is heard 

 both when the bird is perched and when it is soaring in circles. It is a mournful 

 double whistle suggestive of the call of the Wood Pewee. I have written it down 

 as tc-whe'e or tswa-ee' and again as pss-whcc'e. 



153 [347a] Archibuteo lagopus sancti-johannis (Gmel). 

 Rough-legged Hawk. 

 Not uncommon winter visitor. October 25 to May 14. 



In the original Memoir I recorded only six instances of this bird. Only once 

 had I seen it. Since then I have become familiar with it not only in Labrador 

 but at Ipswich and it has even alighted on my windmill within a couple of hundred 

 yards of my house. In fact the regularity with which I have seen one or two, 

 and once four of these birds within a short distance of my house every winter 

 with one or two exceptions since 1905, makes me think that this part of Ipswich 

 near the dunes is a regular winter station or at least a stopping-place during the 

 migrations. Mr. H. W. Wright saw one at Marblehead on January 22, 1907, and 

 one at Nahant on December 17 of the same year. 



The Rough-legged Hawk is a noble bird. It may be known by its large size, 

 broad wings, and long tail. Shaped like a Buteo, its longer tail marks it out, but 

 its distinguishing mark in all but the black phase is its white rump, or rather base 

 to its tail. The only other hawk with this distinguishing mark is the Marsh 

 Hawk, but the much smaller size, slenderer form, narrow wings, and longer tail 

 in proportion make the distinction an easy one. 



