BUTEO SWA1NSON1. 



313 



opportunity occurred. These winter sojourners were also very wild, while on the other 

 hand, thv small southerners were very tame, allowing one to approach within a few yards 

 of them; in fact, upon a certain occasion, one alighted on a low tree within a few feet of 

 me and irn/.cd at inc fearlessly while I walked slowly past. 



Like the Red -tailed, these Hawks are accustomed to circle about, high in air, watch- 

 ing for their prey; at such times, both species resemble each other somewhat, as they both 

 have the same general movements, but the Red-shouldered may be distinguished, even 

 when at a long distance, by the form, for they are shorter in proportion to the spread of 

 wing, than the allied species. To make it clearer, an imaginary circle drawn around the 

 bird, touching the tips of the wings, would pass outside the tip of the tail, while with the 

 Red-tailed, this line would pass through the terminal portion of the tail. 



When moving about as described, the Red -shouldered Hawks occasionally give vent 

 to shrill screams which become louder and harsher when their nesting places are approached. 

 When the male is paying court to the female, he utters a peculiar chucking sound and is 

 very assiduous in his attentions to her, offering her food and seldom leaving her. Even 

 when she is sitting, he not only provides her with all she wants to eat but, like nearly all 

 other Hawks, shares the duties of incubation with her. When not otherwise engaged, he 

 guards the vicinity of the nest vigilantly and, upon the approach of an intruder, gives no- 

 tice to his mate, and she silently leaves the nest. I observed the Red-shouldered Hawks 

 nesting in Florida early in February and obtained three young from a nest, built in a cy- 

 press tree which stood in a small pond in the piney woods in the vicinity of Salt Lake. 

 This was on the tenth of April and then the young were two or three weeks old, for the 

 leathers were just starting. Judging from this instance, the eggs must be deposited about 

 the first of March in the South. Further north, however, they breed a little later, from 

 the first of April until May, the time of nesting being regulated, apparently, by the sea- 

 son. According to my experience, these Hawks prefer deciduous trees which grow in 

 swampy land, in which to build, but I have occasionally taken the nest from pines. They 

 do not select particularly large trees; in fact, I have more than once taken the eggs from 

 nests, not over twenty feet from the ground; that, too, in woods where there was an abun- 

 dance of trees of a much larger size. 



The Red-shouldered Hawks are only partly migratory, at least in Massachusetts and 

 southward, for they remain with us all winter, frequenting the vicinity of meadows in 

 which there are open springs, in order to feed upon the frogs which resort to such places 

 during the cold season. 



BUTEO SWAINSONI. 



Swainson's Hawk. 

 Butio Swatnsoni Bo.v., List; 1838, 3. 



DESCRIPTION. 



Si. Cn. Form, not tery robust. Size, medium. Tarsus, feathered in front for less than half its length. Only three 

 outer qui!l are incited on the inner webs. Sexes, not similar in color in the adult stage. 



