36 Fry, Seasonal Decline in Bird Song. [j 



Auk 



an. 



about July 20, and the falling off continued bit by bit throughout 

 the rest of the period. On August 10 it was singing infrequently. 



The Song Sparrow {Melospiza melodia melodia) began to lose 

 in volume and frequency about the twenty-first. Its decline, like 

 that of the Pewee and Red-eyed Vireo, was very gradual, and there 

 were days after the twenty-first when its cheering song could be 

 heard quite often, but by August 10 it was singing only occasion- 

 ally. 



The data for the Meadowlark (Sturnella magna magna) are not as 

 full as for most of the other species, and at best it was heard but 

 seldom. Since only a few were seen at intervals it is difficult to 

 determine whether or not the species was still in full song July 1. 

 The frequency with which it sang the first week remained about 

 constant till around the twenty-first, and after that it was heard 

 but rarely. The last song recorded is on August 7. 



The trill of the Chipping Sparrow {Spizella passerina passerina) 

 began to diminish July 22. The decline was not rapid, and like 

 the Song Sparrow, it could be heard daily throughout the remainder 

 of the period, but each week witnessed a decided lessening, and 

 during the last few days it was heard but seldom. 



The Towhee (Pipilo erythrophthalmus erythrophthahnus) was 

 heard frequently, though locally, in song and call to the twenty- 

 third. From that date the decline set in, though gradually, and 

 both song and call were noted occasionally, during the remainder 

 of the period though each week becoming less. 



The Black and White Warbler {Mniotilta varia) did not begin 

 its song decline till July 26. The diminution was not rapid and 

 was scarcely perceptible day by day. August 10 it was heard 

 occasionally. 



The Flicker (Colaptes auratus luieus) was heard calling daily 

 throughout the entire period, though after Jul}^ 25 it was not quite 

 as much in evidence. This date marked a diminution, but a very 

 slight one, and the calls at the close of the studies were almost as 

 frequent as during the first week. 



The calls of the Acadian Flycatcher (Empidonax virescens) were 

 observed frequently, though locally, to the twenty-sixth, when a 

 rapid decline set in, and it was last heard August 2. 



Data on the Barn Swallow {Hirundo erythrogastra) are rather 



