ARIZONA SULPHUR-BELLIED FLYCATCHER 105 



chooses as his singing perch the topmost dead twig of a tall tree 

 standing in a clearing or at its edge; and here, his dark form con- 

 spicuous against the brightening sky, a hundred feet above the dew- 

 laden earth, he pours forth his dawn-song for many minutes together. 

 Tre-le-re-re, tre-le-re-re he repeats tirelessly over and over, in a soft, 

 liquid, almost warbling voice. One morning I timed a bird that 

 sang for 17 minutes without a pause. During the hours of full day- 

 light this appealing song is rarely heard, and then chiefly when the 

 flycatcher is excited by a rival of his own kind, or else in brief 

 snatches, at the beginning of the nesting time, as if he were prac- 

 ticing. "Wliat a contrast between this soft, cool, pellucid dawn-song 

 and the high-pitched, strained, excited notes that the bird utters at 

 other hours of the day." 



Others have noted similar vocal utterances in Arizona, the morn- 

 ing and evening song and the loud, shrill, screeching call note, which 

 sounds much like the squeaking of a wagon wheel that needs greas- 

 ing. Mr. Willard thought that the song sounds much like the most 

 musical notes of the cowbird; and Mr. Swarth (1904) says: 

 "Though noisy their vocabulary is limited and I have never heard 

 but the one shrill call from them, a note hard to describe but very 

 much in the style of the familiar two-syllabled whistle of the West- 

 ern Flycatcher {Empidonax difjicilis). Of course the volume is 

 infinitely greater than with the little Empidonax, but they resemble 

 each other to this extent, that I have known a person familiar with 

 the Sulphur-bellied Flycatcher to mistake a difficilis near at hand for 

 the larger flycatcher in the distance." 



Field marks. — The sulphur-bellied flycatcher is so unlike any other 

 North American bird that it could hardly be mistaken for anything 

 else ; the white throat and pale yellow abdomen, streaked with black, 

 and the rufous tail, with median dusky stripes, are quite distinctive. 

 And, as it is oftener heard than seen, its characteristic voice will 

 identify it. 



Fall. — Although this is one of the latest arrivals in the spring 

 and a late breeder, it apparently leaves for the south as soon as the 

 young are able to follow. We have few Arizona records later than 

 August 24. Even in Costa Kica, Mr. Skutch saw very few after the 

 middle of July, and he has not seen it anywhere in Central America 

 between September and February; and the latest date he gives me 

 is August 9. Evidently the winter home is somewhere in South 

 America. 



DISTRIBUTION 



Range. — Southern Arizona and Central America south to Ecuador 

 and Peru. Resident except in extreme north. 



Breeding range. — The sulphur-bellied flycatcher breeds north to 

 southern Arizona (Pima Canon, Caiion de Oro, and the Chiricahua 



