298 BULLETIN 179, UNITED STATES NATIONAL MUSEUM 



From this lookout perch it can warn its mate of approaching danger, 

 or oftener sally forth in any direction to snatch its insect prey. Often 

 it returns to the same perch or, if its flight has been a long one, it 

 may select any one of its favorite observation posts. Anna Head 

 (1903) watched one "as it whirled and tumbled in the air in frantic 

 pursuit of a moth, it almost seemed to be coming to pieces, so loosely 

 was it jointed, till a loud clich of the beak announced success, and 

 in an instant it was back on its perch, looking as if it had always 

 sat there." 



W. F. Henninger (1916) gives the following account of an unusual 

 flight behavior that he noted near New Bremen, Ohio, on October 11, 

 1911 : "In the dry tops of two large trees about 17 meters apart from 

 one another, there were two specimens of this species. While the one 

 sat perfectly motionless preening its feathers occasionally, the other 

 one began to fly upward in very short spirals and then to descend in a 

 number of jerky drops with quickly expanded and closed wings. After 

 doing this a number of times it finally flew so high that it disappeared 

 from sight altogether and it did not return at all." 



Voice. — Its voice is the most prominent and characteristic feature of 

 the olive-sided flycatcher, by which its presence is oftenest detected. 

 On its breeding grounds its loud, ringing, somewhat musical calls may 

 be heard from the first crack of dawn to the deepening twilight of eve- 

 ning; its notes are so constantly uttered at times that they become 

 fairly tiresome. Mr. Eathbun says, in his notes: "On one occasion, 

 when I was at a mountain lake resort, the owner asked me to 'shoot up' 

 a pair of the olive-sided, which he said made so much noise that they 

 annoyed some of the guests." Grinnell and Storer (1924) say that, in 

 the Yosemite, "the Olive-sided Flycatcher is one of the earliest birds 

 to call in the morning and one of the last to be heard in the evening. 

 This is probably due in some degree to its choice of surroundings, for 

 in the tree tops it is apprized of the coming of dawn long before that 

 news reaches the earthward dwelling species, and in the same places it 

 enjoys the lingering daylight for some time after the glades and 

 thickets below are lost in the shadows of the evening." 



Many different descriptions of the voice of the noisy olive-sided fly- 

 catcher have been published, far too many to be quoted here, and I 

 have also a number of contributed notes on the subject. The most dis- 

 tinctive note is the 3-syllabled call note, which might be considered the 

 song of the male on the breeding grounds. The first of the three 

 syllables is short and sharp, but not so loud as the others and not 

 audible at so great a distance, so that the note may then appear to have 

 only two syllables. The other two syllables are very loud, emphatic 

 notes and are strongly accented. Perhaps the best rendering of this 

 call is that given me by Francis H. Allen, as whip-whee-peeoo^ "the 

 whip not carrying very far and perhaps sometimes omitted — a loud 



