204 HOMING WITH THE BIRDS 



male birds sing, while I am hidden with a camera 

 near the mate to which they sing, I have learned 

 that this is much more common among birds than 

 is generally known. Almost all of them sing whis- 

 per songs that must be for their own pleasure. 



Sometimes bird song is trailed over the fields, 

 beside the river, and through the woods, inter- 

 spersed with snatches of food and playful darts 

 after other birds. But when really singing and 

 enjoying their own performance, the beak is pointed 

 upward to a greater or less degree — greater among 

 very small birds — the throat swells, the feathers 

 of the breast and back ruffie over the wings so that 

 the impression is formed that the wings are pressed 

 tightly to the sides; the tail is folded and bends 

 under the body slightly, and the beak parts nar- 

 rowly in some species, widely in others. 



The song of all songs is the passion song. In this 

 the males make their supreme effort. It begins 

 when the mating fever attacks them, intensifies 

 in pursuit of a mate, and reaches the acme, the 

 fullest force and expression, immediately prior 

 to the act of mating. The catbird then surpasses 

 himself; the wood thrush, hermit thrush, and brown 

 thrasher outsing their sweetest performances; the 

 oriole flames in voice as in body; and the chewink 

 is an insistent and irresistible wooer. But I know 

 of no other bird that in the stress of mating fever, 

 so swells, prolongs, and trills his notes, so spreads 

 and rocks himself, and displays his charms, as the 



