MOURNING DOFE 279 



feeding in open fields, coming to streams and springs morning and evening 

 to drink, and roosting in trees or along roadside fences. On June 11, 1916, 

 a flock of at least 75 doves was seen by Mr. Donald D. McLean on Smith 

 Creek, east of Coulterville. The birds were feeding on the seeds of wild 

 portulaca. 



Turkey Vulture. Cathartes aura septentrionalis Wied 



Field characters. — General appearance that of ' ' bird of prey ; ' ' size large, about 

 that of Eed-tailed Hawk; plumage black, with faintly gray area on lower surface of 

 wing (pi. 44e) ; head red, nearly naked. Voice: A low hiss, rarely uttered. Usually 

 seen soaring overhead in wide circles, with wings slanting upward. When perched, sits 

 in a hunched-up posture, with head drawn in between shoulders. 



Occurrence. — Common in summer on west slope of Sierra Nevada, in both Lower and 

 Upper Sonoran zones. Easternmost point of regular observation, 3 miles east of Coulter- 

 ville, at 3200 feet altitude. Tmce noted over Yosemite Valley in summer of 1920 

 (C. W. Michael, MS). 



As a rule, most large birds of the Yosemite section are so uncommon 

 that to observe one of them is a notable occurrence. The Turkey Vulture, 

 or Buzzard as it is called locally, is, within its range, a conspicuous excep- 

 tion. All over the western country below the Transition Zone, it is common 

 and present throughout the greater portion of the year. 



In bulk the Turkey Buzzard about equals the Red-tailed Hawk; it is 

 of only about one-third the weight of the Golden Eagle. Its black plumage, 

 and the grayish patch on the under surface of each wing, make it easy 

 to distinguish from all our other birds of prey. In flight the tips of the 

 outermost five or six primary flight feathers are distinctly separated like 

 the spread fingers on a person's hand (pi. 44e), but the tail is held closed 

 so that, seen from below, it has a narrow, wedge-shaped outline. The 

 Turkey Buzzard spends a very large share of its time on the wing, sailing 

 about in almost unceasing watch for food. When soaring, the buzzard 

 usually holds its wings bent upward, so that a more or less distinct angle, 

 with the apex downwards, is formed between them. Ofter a bird will soar 

 in circles for several minutes at a time without appearing to alter the 

 position of a single feather, accommodation to differences in the air cur- 

 rents seemingly being made by movement of the body as a whole. As 

 the bird glides down over the brush of a caiion side, it often careens from 

 side to side, but without changing the relative positions of wings or tail. 



These big birds distribute themselves over their range with remarkable 

 uniformity. Probably the average population is but one or two individuals 

 to the square mile. Each seems to be scrutinizing a definite area; if one 

 bird discovers any large item of food the others quickly take notice. As 

 the original discoverer of the food with obviously increased animation 

 drops down onto his find, his nearest neighbors cease their patrolling and 



