BIRDS OF THE CAMBRIDGE REGION. 189 



86. Archibuteo lagopus sancti-johannis (Gmel.). 

 American Rough-legged Hawk. Rough-legged Hawk. 



Transient visitor in spring and autumn, sometimes not uncommon at the latter season. 



seasonal occurrence. 



March 25, igoo, one seen, Fresh Pond, W. Deane. 

 May 8, 1879, one seen. Rock Meadow, VV. Brewster. 



November 3, 1873, one seen, Fresh Pond Marshes, W. Brewster. 



November 10 — 30. 

 December 28, 1901, one seen, Rock Meadow, R. S. Eustis. 



The favorite haunts of the Rough-legged Hawk in the Cambridge Region 

 are Rock Meadow and the Fresh Pond Marshes. Here the sluggish but grace- 

 ful birds, larger than any of our other Hawks and showing conspicuously white 

 upper tail-coverts, may be seen in late autumn, perched among the upper 

 branches of isolated trees or beating about over the marshes, occasionally pois- 

 ing at no great height above the ground on apparently motionless wings as if sus- 

 pended by an invisible wire. This remarkable feat, practised also by the Euro- 

 pean Kestrel and by our Sparrow Hawk, is possible, I believe, only when 

 there is a light, steady wind. 



In November, 1873, I noted no less than five different Rough-legged 

 Hawks at the localities above named, but it is exceptional to see so many in the 

 course of a single season and during some years none are reported. I have met 

 with but one in spring — at Rock Meadow on May 8, 1879. This is a late date, 

 for at Northampton, where the species occurs regularly, and at times rather 

 numerously, during the vernal migration, it seldom or never lingers after the mid- 

 dle of April. There can be no question that the bird seen at Rock Meadow was 

 correctly identified, for I had an excellent view of it and made out all its charac- 

 teristic markings with perfect distinctness. The only other spring record that I 

 can give for the region about Cambridge is that of a bird which Mr. Walter 

 Deane observed on March 25, 1900, flying over Fresh Pond, closely pursued by 

 some Crows. 



Mr. Richard S. Eustis tells me that in 1901 he saw a Rough-legged Hawk 

 near Fresh Pond on December 8, and another at Rock Meadow on the 26th and 

 again on the 28th of the month ; — dates which suggest that the species may 

 sometimes spend the winter in our neighborhood, as it is known to do, in very 

 limited numbers, in certain other parts of Massachusetts. 



